CLU-IN Technology Innovation News Survey

CURRENT KNOWLEDGE ON PHYTOREMEDIATION POTENTIAL OF INDUSTRIAL HEMP (CANNABIS SATIVA L.) FOR PFAS AND HEAVY METAL CONTAMINATED SOILS [General News]

Thu, 7 May 2026 14:00:53 GMT

Ansari, O. and L. De Prato. | Remediation 36(2):e70059(2026)

This review compiles current research on the phytoremediation potential of industrial hemp (Cannabis sativa L.) for heavy metals, including arsenic, aluminum, mercury, copper, lead, cadmium, nickel, and zinc, as well as PFAS. Interdisciplinary studies were conducted across greenhouse, field, hydroponic, and amendment-based experiments. Findings indicate that hemp exhibits strong tolerance and accumulation capacity for cadmium, lead, and arsenic, with metal uptake primarily concentrated in roots. Cultivar differences significantly influence both uptake efficiency and biomass yield. PFAS uptake is selective, with higher bioconcentration observed for short-chain and carboxylic acid compounds, although overall soil PFAS removal remains low to moderate. Remediation efficacy is modulated by soil properties, biosolid amendments, and microbial symbioses, which enhance PFAS bioavailability and plant tolerance. Comparative assessments reported in the literature suggest that hemp's rapid biomass production and adaptability may offer advantages over other phytoremediation species. However, limitations in PFAS degradation and ecological risks, such as PFAS accumulation in pollen, persist. Integration of soil amendments and microbial inoculants shows potential to enhance hemp growth rates and PFAS tolerance; however, further testing and field validation are required. The review underscores hemp's potential as a sustainable phytoremediation agent and a component of integrated PFAS remediation strategies, while highlighting the need for standardized protocols and risk assessments to ensure environmental safety and practical scalability. https://onlinelibrary.wiley.com/doi/epdf/10.1002/rem.70059

A RECENT OVERVIEW OF PHOTO ELECTRO CATALYTIC MATERIALS MECHANISTIC INSIGHTS TOWARDS PFASS DEGRADATION: BY-PRODUCTS DETERMINATION AND AI/ML IMPLICATIONS [General News]

Thu, 7 May 2026 13:59:36 GMT

Penke, Y.K., P. Chamoli, and H.-M. Lo. Chemosphere 397:144852(2026)

This review examines the electrochemical and photocatalytic activities of various materials/composites that degrade PFAS. Technical observations are primarily referenced from recent literature published between 2020 and 2025. Iron and titanium species have shown better remediation abilities, which was reported in the majority of publications. Iron systems have shown better parameters for electrochemical activities (electrooxidation/reduction), whereas titanium suboxides and bismuth sheets are better related to the photoelectrochemical activity. Other 3D metal systems like Co, Ni, and boron-doped diamond, carbon structures (activated carbon, carbon sphere, and aerogel) are also detailed with PFOA and PFOS treatment. In understanding the degradation mechanism, the radical species activity has densely dominated the process with the support of radical oxygen/sulphur species and charge transfers. Radical species activity, dissolved oxygen influence, and direct electron transfer mechanism are provided to understand the heterogeneous catalytic reactions and redox materials chemistry. Decarboxylation and hydro-defluorination mechanisms are explained with a set of findings based on the catalyst and compound chain length. Determination of degradation byproducts and intermediates utilizing different state-of-the-art spectroscopy tools is detailed to support the issue related to the secondary contamination in various remediation sites and the necessary field studies findings. Implications of AI/ML towards efficient handling of the various PFAS treatment and management technologies are discussed briefly.

WEB-BASED TOOLS FOR DATA-INFORMED REMEDY OPTIMIZATION: SOFTWARE THEORY AND USER GUIDE [General News]

Thu, 7 May 2026 13:59:20 GMT

Song, X., F. Lopez Jr., M. Corney, P. Tran, Y.S. Afzal, T.E. Joppich, S.N. Baur, H. Luu, R. Osman, C.D. Johnson, and I. Demirkanli. PNNL Report PNNL-38413; DVZ-RPT-121, 50 pp, 2025

This report documents the development and application of two web-based decision-support tools for PTOLEMY (Pump-and-Treat Optimized Location Evaluation to Maximize Yields) and OPTIMA (Optimization for Pump-and-Treat Implementation, Management, & Assessment). These tools enhance remedy design and management by leveraging advanced computational methods (deep learning and multi-objective optimization) within a user-friendly platform. By integrating data-driven models with established hydrogeological knowledge, PTOLEMY and OPTIMA enable more efficient evaluation of well placement and operational strategies, helping site managers balance multiple remediation objectives under complex conditions. Both tools are implemented as modules within the Suite Of Comprehensive Rapid Analysis Tools for Environmental Sites (SOCRATES) web platform, which provides data access, visualization, and analytics to support remedy optimization across sites. Both PTOLEMY and OPTIMA are intended as decision support tools to guide and streamline P&T design processes, not as replacements for site-specific modeling or regulatory decision-making requirements. They provide preliminary analyses that must ultimately be confirmed with high-fidelity models and engineering review. The tools are designed for transparency and traceability; they draw from established data sources and allow users to export maps, data tables, and configurations for documentation. By accelerating the exploration of "what-if" scenarios and narrowing down options, PTOLEMY and OPTIMA support more informed, timely, and cost-effective decision-making in P&T remedy management. https://www.osti.gov/servlets/purl/3001001

ACID TAR LAGOON REMEDIATION I: BASELINE GEO-ENVIRONMENTAL CHARACTERIZATION AND PRELIMINARY STABILIZATION/SOLIDIFICATION MIX DESIGNS [Research]

Thu, 7 May 2026 13:59:06 GMT

Grubb, D.G., D.R.V. Berggren, and E.K. Helbling. Remediation 36(2):e70061(2026)

A treatability study is presented that describes the baseline geo-environmental characterization and pH buffering of soil surrogates containing 20% (S2X) or 40% (S4X) acid tar by volume (where X denotes testing phase) and various stabilization/solidification (S/S) mix designs using powdered ladle slag (PLS), a 60/40 (w/w) blend of Type IL Portland Cement (PC) and Grade 120 NewCem (NC) slag cement, and bentonite (B) for some mixes. The soil surrogates reflected the expected in situ S/S (ISS) profile comprising an ISS rig working platform, residual tar, bottom lagoon liner materials, and shallow subsurface soils after the bulk tars are excavated for incineration. The total benzene content of the S41, S42, and S22 soil surrogates averaged 16,300, 24,000, and 10,568?mg/kg, respectively, with corresponding sulfur contents of 28,350, 93,500, and 43,500?mg/kg and pH values typically less than 0.5. EPA 1313 testing on the S41/S42 soil surrogates tracked the leaching of EPA target analyte list metals over a range of pH and also indicated that it took about three equivalents of base addition to maintain pH conditions above 8 to ensure the long-term stability of the ISS mixes. EPA 1316?M leaching of VOCs indicated that the S41, S42, and S22 media were characterized by benzene effective concentrations of 497, 406, and 318?mg/L, respectively. The S41 and S42 surrogates were extremely challenging to solidify, requiring 5?wt% PLS?+?35?wt% PC/NC to exceed the relatively modest unconfined compressive strength (UCS) target of 276?kPa (40?lb/in²). Regardless of UCS, most ISS mixes met the permeability criterion of less than 1×10^-6 cm/s. The minimum ISS reagent dose satisfying the UCS, K, and residual pH buffer capacity (3?meq/g) targets for 28-day cured mix designs for the S22 soil surrogate was 5?wt% PLS?+?30?wt% PC/NC?+?0.5?wt% B. This was the minimum reagent dose proposed for long-term leaching and field pilot testing.

HUMAN IN VITRO METABOLISM OF AN ENVIRONMENTAL MIXTURE OF POLYCYCLIC AROMATIC HYDROCARBONS (PAH) FOUND AT THE PORTLAND HARBOR SUPERFUND SITE [Research]

Thu, 7 May 2026 13:58:38 GMT

Gaither, K.A., K. Tyrrell, W. Garcia, K.A. Anderson, and J.N. Smith.
Toxicology Letters 412:172-181(2025)

A study aimed to measure human metabolism rates of Supermix-10, the ten most abundant PAHs found at the Portland Harbor Superfund site, to support the development of human pharmacokinetic models. Individual PAHs were incubated from Supermix-10 in pooled human liver microsomes and quantified parent PAH disappearance using high-performance liquid chromatography with UV and fluorescent detection. To assess the potential of mixture interactions, the metabolism of all 10 compounds was measured in an equimolar mixture, and the rates of parent disappearance were compared to those observed for individual PAHs. All Supermix-10 PAHs demonstrated rapid parent compound disappearance in human hepatic microsomes. PAHs are grouped into high metabolism rates and capacity (2-methylnaphthalene, acenaphthylene, fluorene, naphthalene), high-affinity metabolism that rapidly achieves low-level saturation (benzo[a]anthracene, chrysene), and moderate metabolism rates and capacity (fluoranthene, pyrene, retene, phenanthrene). Smaller PAHs exhibited faster metabolism, and higher metabolism rates correlated inversely with molecular weight. When incubated in an equimolar mixture, Supermix-10 demonstrated significantly slower metabolism (47-89?%) compared to the metabolism of individual PAHs at the same concentration. Findings enhance understanding of PAH metabolism in humans and demonstrate significant mixture interactions under the conditions tested. They also offer insights into the metabolic behavior of Supermix-10 and provide critical metabolism rate data to support the development of physiological based pharmacokinetic models.

MEASURING FLUOROTELOMER ALCOHOLS BY THERMAL DESORPTION-GAS CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY: INTERLABORATORY STUDY RESULTS [Research]

Thu, 7 May 2026 13:58:23 GMT

Eichler, C., H. Calder, B. Chandramouli, M. Curtis, H. Hayes, B. Kim, R. Marfil-Vega, C. Mejías, L. Miles, A. Owens, J. Stuff, K. Thaxton, J. Vandenberg, N. Watson, D. Wevill, J. Whitecavage, and X. Liu. | Journal of Chromatography A 1769:466725(2026)

An international interlaboratory study (ILS) was conducted with nine labs to evaluate the precision of ASTM International Standard Test Method D8591 to measure fluorotelomer alcohols (FTOHs). The test method specifies the analysis of four FTOHs (4:2, 6:2, 8:2, and 10:2 FTOH) collected on PFAS-specific thermal desorption tubes by gas chromatography coupled with tandem mass spectrometry. During the ILS, participating labs were instructed to use the test method to analyze three samples (A, B, and C) three times. Each sample contained the target FTOHs at defined concentrations unknown to the labs. The results from seven laboratories show that the relative reproducibility standard deviation (RSD_R) of the method ranges from 14% to 26%, and the relative repeatability standard deviation (RSD_r>/sub>) ranges from 4.6% to 11%, with RSDs decreasing with decreasing volatility of the FTOHs. Bias ranged from -13% to 6.0% and was generally larger and negative for less volatile FTOHs. The test method, in conjunction with the precision statistics from this ILS, will provide a reliable, defendable method that can be used in the context of studying PFAS sources, transport, and human exposure.

SUSTAINABILITY ASSESSMENT OF ALTERNATIVE METHODS FOR DESTRUCTION OF PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS) IN WATER [Research]

Thu, 7 May 2026 13:58:07 GMT

Mohamed, M.S. and K.R. Reddy. | Remediation 36(2):e70054(2026)

Research aimed to evaluate the sustainability of three methods for destroying PFAS: incineration, electrochemical oxidation (EO), and ultraviolet advanced oxidation processes (UVAOP). The triple bottom line sustainability framework was used to evaluate the environmental, economic, and social aspects of the destruction methods. Environmental consequences were evaluated through a life cycle assessment implemented in SimaPro. Economic sustainability was assessed by analyzing direct and indirect costs. Social implications were evaluated using the Social Sustainability Evaluation Matrix. Furthermore, the Integrated Value Model for Sustainability Assessment was used to integrate the results of environmental, economic, and social sustainability assessments. Results show that EO is the most sustainable method with a sustainability index (SI) of 0.90, followed by UVAOP (SI?=?0.48), whereas incineration is the least sustainable (SI?=?0.29), under balanced weighting criteria. https://onlinelibrary.wiley.com/doi/epdf/10.1002/rem.70054

INITIAL UNCERTAINTY ANALYSIS OF CARBON TETRACHLORIDE CONTAMINATION AND REMEDIATION IN THE RINGOLD A AND LOWER MUD UNITS AT THE CENTRAL PLATEAU [Research]

Thu, 7 May 2026 13:57:51 GMT

He, X., M. Rockhold, and X. Song. PNNL Report PNNL-38406, 16 pp, 2025

The long-term effectiveness of groundwater cleanup at the Hanford Site Central Plateau depends on predictive models that can capture key uncertainties in contaminant fate and transport. Carbon tetrachloride (CCl_?) presents challenges due to variability in degradation rates, uncertainty in initial plume distribution, and subsurface heterogeneity, which directly influence plume persistence, migration pathways, and remedy performance. A large-scale Monte Carlo analysis was conducted using the Plateau to River (P2R) model framework that parameterized degradation rate, initial plume distribution, and hydraulic conductivity. Degradation was represented as a first-order process, with half-lives ranging from 70 to 700 years. Initial plume distributions were created using a geostatistical simulation method (sgsim), which generates many equally plausible versions of how contaminants might be distributed underground. From this, 100 different scenarios were mapped onto the P2R grid. Variability in hydraulic conductivity was represented similarly, with 100 scenarios each for the Ringold Lower Mud and Ringold A units (layers 6 and 7), based on fitted exponential variograms and conditioned to well data. In total, more than 1,000 realizations were simulated to assess plume behavior under uncertainty. The analysis highlights that uncertainty in degradation rate and initial plume configuration are the primary drivers of variability in plume predictions, while conductivity heterogeneity plays a limited role. Findings underscore the need for improved site-specific data on degradation processes and source characterization to enhance the reliability of long-term performance assessments and to better inform remedial decision-making. https://www.osti.gov/servlets/purl/3000283

BIOASH-BASED STABILIZATION/SOLIDIFICATION FOR HEAVY METAL(OID) SOIL REMEDIATION: A CASE STUDY IN NORTHERN SWEDEN [Demonstrations]

Thu, 7 May 2026 13:57:35 GMT

Khasevani, S.G., I. Carabante, J. Bjuhr, and L. Andreas.
Materials 19(4):790(2026)

A pilot study evaluated bioash-cement composite binder as a low-cement stabilization material for metal-contaminated soils, with an emphasis on mechanical performance and long-term leaching behavior under field conditions. Two fine soil fractions from the Nasudden area, classified as hazardous (HS) and non-hazardous (NHS), were treated in lab trials to optimize binder composition. An optimum formulation containing 35 wt.% bioash and 5 wt.% cement (dry basis, relative to soil) improved unconfined compressive strength (UCS) to 696 kPa (HS) and 479 kPa (NHS) after 28 days and reduced leaching of Zn, Cd, Pb, and Co. Arsenic immobilization improved in HS but decreased in NHS, while Cu and Ni leaching increased, consistent with elevated pH and dissolved organic carbon promoting soluble complexation. The optimized binder was then applied to a third pilot soil and validated at pilot scale by treating 100 tonnes of soil and constructing a 2 m high noise barrier. Parallel lab tests on the pilot soil yielded UCS values of 1000 kPa and confirmed effective retention of Zn and Cd, with generally good Pb stabilization, whereas As remained the most mobile element across soil types. Two-year field monitoring showed decreasing leachate concentrations of As, Cu, Ni, Pb, and Zn over time, and field samples exhibited improved Cu and Ni retention compared with lab results, suggesting progressive aging effects such as carbonation and mineral transformations. Results demonstrate that bioash-cement binders can produce mechanically stable treated materials suitable for low-load applications while reducing cement demand; however, performance is strongly controlled by soil-specific chemistry (notably DOC) and field execution (mixing and compaction), and further binder optimization is required to address arsenic mobility. https://www.mdpi.com/1996-1944/19/4/790

LONG-TERM PERFORMANCE OF PASSIVE VOLATILE ORGANIC COMPOUNDS (VOCS) SAMPLERS FOR INDOOR AIR [Demonstrations]

Thu, 7 May 2026 13:57:19 GMT

Zimmerman, J., B. Schumacher, C. Lutes, B. Cosky, and H. Hayes.
Environments 12(8):267(2025)

The first phase of this study evaluated the performance of Radiello® charcoal-based, solvent-extracted passive samplers over exposure periods ranging from one week to one year in a test house with known vapor intrusion (VI). Chloroform %Bias values exceeded the ±30% acceptance criterion after four weeks of exposure. Benzene, hexane, and TCE concentrations were within the acceptance criterion for up to three months. Toluene and PCE demonstrated uniform uptake rates over one year. In the second phase of this study, testing of the longer exposure times of six months and one year was evaluated with three additional passive samplers: Waterloo Membrane Sampler™ (WMS™), SKC 575 with secondary diffusive cover, and Radiello 130 passive samplers with yellow diffusive bodies. The SKC 575 and Radiello 130 passive samplers produced acceptable results (%Bias ≤ 30%) over the six-month exposure period, while the WMS sampler results favored petroleum hydrocarbon more than chlorinated solvent uptake. After the one-year exposure period, the passive sampler performances were acceptable under specific conditions for this study. Results suggest that all three samplers can produce acceptable results over exposure time periods beyond 30 days and up to a year for some compounds. This article is Open Access at https://www.mdpi.com/2076-3298/12/8/267

TREATABILITY STUDY TO EVALUATE BIOREMEDIATION OF TRICHLOROETHENE AT SITE K, FORMER TWIN CITIES ARMY AMMUNITION PLANT, ARDEN HILLS, MINNESOTA, 2020-22 [Demonstrations]

Thu, 7 May 2026 13:56:57 GMT

USGS, Scientific Investigations Report 2025-5113, 104 pp, 2025

Lab and field treatability tests were completed to evaluate the potential application of anaerobic bioremediation for a shallow TCE-contaminated groundwater plume in a perched alluvial aquifer at Site K, former Twin Cities Army Ammunition Plant. The plume extends beneath Building 103, where soil excavations left some deeper contaminated soil in place within the TCE source area. The report describes the study, including the pre-design site characterization to assist in formulating the bioremediation approach, lab experiments to support the design of the pilot test, and implementation and one-year performance monitoring results. The pilot test utilized three separate test plots, each about 30-ft wide and 60-ft long: plots GS1 and GS2 in the source area of the plume and plot GS3 in the downgradient area of the plume near the excavation trench. Each test plot had one injection well, one monitoring well upgradient from the injection point, and 12 surrounding monitoring wells in a grid to capture variable groundwater flow directions. Performance monitoring included hydrologic measurements and analyses of cVOCs, redox-sensitive constituents, dissolved organic carbon, bromide, volatile fatty acids, compound-specific carbon isotopes, and microbial communities. Data collected during the tests showed that enhanced, complete reductive dechlorination of cVOCs in the groundwater was achieved in the GS1 and GS3 plots. In contrast, evidence of the distribution of the injected amendments and subsequent biodegradation was limited in GS2, which was in an area of more heterogeneous soil lithology and low water table elevations. The pilot tests showed that the relatively low hydraulic head gradients and temporal changes in groundwater flow directions in the shallow aquifer would add complexity to a full-scale bioremediation effort. The radius of influence (ROI) at GS1 and GS3 was close to the design ROI of 15 ft. The estimated ROI at GS2 was about four times the design ROI, but it may be less reliable at this location due to groundwater flow direction. In addition, the low temperatures following WBC-2 injection, combined with the low hydraulic head gradients, were probably major factors in the delay observed before the onset of enhanced biodegradation following injection of the culture. Additional test injections could be beneficial to optimize the timing of donor and culture injections with the variable temperatures and hydraulic head in the shallow aquifer. https://pubs.usgs.gov/sir/2025/5113/sir20255113.pdf

GROUNDWATER RESTORATION AND LONG-TERM STEWARDSHIP AT A FORMER SMELTER [Cleanup News]

Thu, 7 May 2026 13:56:36 GMT

Hay, M. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 15 slides, 2026

Remedial design and construction activities were completed for a former lead and copper smelter in El Paso, Texas. Groundwater across a portion of the site is impacted primarily with arsenic, with the highest concentrations and the majority of groundwater flow focused along former arroyos. These features represent the greatest contribution of contaminant mass flux toward offsite receptors and are the key to an integrated strategy for remedial design/remedial action. The optimized remedial approach involved a shift from concentration-based compliance to mitigating contaminant flux to protect downgradient receptors. A combination of source control measures and passive groundwater management and treatment approaches was selected to achieve remedial goals and balance the needs of future site development. The remedial approach involves source control, water management, and in situ groundwater treatment, including zero-valent iron (ZVI)-based permeable reactive barriers (PRBs). Site arroyos consist of coarse, highly permeable alluvial deposits, which result in a high groundwater flux system. These conditions required PRB designs with high permeability, sufficient groundwater residence time, and iron content consistent with contaminant loading rates and desired treatment longevity. In the largest arroyo, two ZVI PRBs were constructed in series to passively treat site groundwater and reduce contaminant mass flux. Results indicate that the zero-valent iron barriers have been highly effective for arsenic removal from groundwater, despite treatment challenges driven by groundwater alkalinity and dissolved calcium. The presentation reviews the pre-design testing, key design elements, and field-scale performance of passive groundwater treatment through the reactive barriers. It also provides an overview of the overall remedial construction, including strategies for water management across the site. https://mediacdn.guidebook.com/upload/213718/ZlKj3UQYiVJJeiHQsL4a2B0aGSD3iH1ktQNv.pdf

REMEDIAL ACTION CONSTRUCTION CASE STUDY-EXCAVATION/CONSOLIDATION AND ISS REMEDY, EPA REGION 6, MARION PRESSURE TREATING SUPERFUND SITE, RES CLIN2 CONTRACT TASK ORDER [Cleanup News]

Thu, 7 May 2026 13:56:18 GMT

Watters, C. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 16 slides, 2026

This presentation describes the implementation of remedial action (RA) activities at the Marion Pressure Treating Superfund site. A total of 7,000 CY of DNAPL (creosote) impacted soil was excavated and consolidated in an onsite waste repository. A combined remedial approach was implemented using the in situ soil stabilization (ISS) of ~29,186 CY of DNAPL-impacted soil by large diameter auguring methodology. The construction of a final landfill cap, including final site restoration for permanent erosion control and drainage improvements were also completed as part of the RA. The presentation focuses on the successful mitigation of RA construction challenges and change management approaches, including:

Incomplete site investigation and characterization.

Project delay from additional treatability study testing to evaluate an alternative cement mixture due to difficulties in obtaining Portland Type II cement.

Control of rainwater and excavation flooding.

Understanding and calculating swell quantities and percentages that change depending on soil conditions, which can affect the required footprint or elevations for containment/ landfill areas.

ISS and clay placement work during the wet season created challenges. Import borrow sites may also be impacted by storms.

Locating import materials that meet all the specifications (permeability for clay and plasticity index, organic content, and pH too low for topsoil) in a rural area may be difficult.

https://mediacdn.guidebook.com/upload/213718/pbHtLIF6AeXPWaq5qjkDRBuqTJu1n6XBwGBW.pdf

BUILDING 100 GROUNDWATER BIOREMEDIATION AT THE FORMER DOE PINELLAS PLANT, FLORIDA: REVIEW OF PROGRESS AND OPPORTUNITIES [Cleanup News]

Thu, 7 May 2026 13:55:59 GMT

Looney, B.B., H.H. VerMeulen, and E.D. Fabricatore. SRNL Report SRNL-STI-2025-00262, 58 pp, 2025

Operations at the former Pinellas Plant, particularly in the Building 100 area, resulted in the release of chlorinated organic solvents that contaminated subsurface soil and groundwater. DOE implemented bioremediation as the primary cleanup technology, targeting cVOCs through reductive dechlorination processes that sequentially transform trichloroethylene into daughter products such as dichloroethylene and vinyl chloride. Over more than two decades, monitoring data indicates substantial progress toward remedial goals, with parent cVOC concentrations now reduced to near or below target standards across most of the site. Remaining contamination is largely confined to a localized hot spot beneath Building 100, which continues to act as a source of mass flux sustaining a narrow plume core where daughter product concentrations exceed remedial thresholds. Bioremediation has been supported by multiple deployments using state-of-the-practice and state-of-the-art technology and design strategies, including vertical and horizontal wells for improved access and coverage, and biostimulation and bioaugmentation. To prepare for the next stages of the bioremediation and related decision-making, DOE developed several lines of inquiry, including evaluating whether remediation optimization is needed by assessing the necessity of additional electron donor or bioaugmentation, identifying improved performance metrics, exploring alternative technical and regulatory strategies, and considering future site changes that could impact the cVOC plume and bioremediation progress. The Building 100 area will transition from active bioremediation to an enhanced attenuation (EA) remedy. Recommendations include transition to an optimized EA strategy that relies on natural geochemical zoning without additional biostimulation or bioaugmentation, while incorporating targeted contingencies for hotspot treatment and mid-plume oxygen limitations, strengthening monitoring by aligning with EPA MNA multiple lines of evidence, regularly monitoring the subsurface microbiology in a few locations to provide data on the resilience of the EA bioremediation strategy, document the responsiveness of the microbial community to site conditions, and verify that the enzymes are present to address the specific needs over time. https://www.osti.gov/servlets/purl/3023071

F -- EMERGENCY REMEDIAL RESPONSE SERVICES (ERRS VI) (SOL) [Market/Commercialization]

Thu, 7 May 2026 13:55:44 GMT

U.S. Environmental Protection Agency, Region 1 Contracting Office, Boston, MA
Contract Opportunities on SAM.gov 68HE0125R0004, 2026

This is a total small business set-aside under NAICS code 562910. EPA Region 1 seeks a contractor to support activities associated with emergency response, including sampling, monitoring, site stabilization, containment of spilled materials, waste treatment, restoration, removal actions, transportation, and disposal. Response activities include planning; containment and countermeasures during emergency and removal responses; decontamination and mitigation; treatment, transportation, and disposal operations; restoration; analytical services; demolition; construction and support facilities for removal actions; marine (water) operations; international (transboundary) response; and response times, Level A response capabilities, and integration into the Unified Command (Incident Command System). The contractor shall provide environmental response services for the removal and treatment of oil, petroleum products, hazardous substances, pollutants, and contaminants, as specified in task orders (TOs). The contractor shall also support response actions related to natural and manmade disasters, acts of terrorism, weapons of mass destruction, and chemical, biological, radiological, and nuclear incidents. The award will be an indefinite-delivery/indefinite-quantity contract with fixed rates for labor and equipment and cost-reimbursable elements for other direct costs. Task orders may be issued on a time-and-materials (T&M) or fixed-price basis. The period of performance is from November 30, 2026, through November 29, 2031. Offers are due by 2:00 PM EDT on July 27, 2026. https://sam.gov/workspace/contract/opp/4d9d08a5e4ee473d8b320598529ac6d0/view

F -- F108--32C24126Q0324 BEDFORD RADIATION DECOMMISSIONING (COMBINE) [Market/Commercialization]

Thu, 7 May 2026 13:55:17 GMT

U.S. Department of Veterans Affairs, 241-Network Contract Office 01, Togus, ME
Contract Opportunities on SAM.gov 36C24126Q0324, 2026

This is a service-disabled veteran-owned small business set-aside under NAICS code 562910. The U.S. Department of Veterans Affairs requires a contractor to perform radiological decommissioning of approximately 20 rooms (approximately 6,300 total square feet) in Buildings 17, 18, 70, and 79 at the VA Bedford Healthcare System, Bedford Campus, in Bedford, Massachusetts. Services include review of a historical site assessment and completion of a radiological final status survey in accordance with the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM). The contractor and any subcontractors must be licensed by the Nuclear Regulatory Commission or the Commonwealth of Massachusetts to perform decommissioning work at sites where radioactive materials have been used. The contractor shall comply with interim life safety plans, infection control measures, and egress requirements during construction; coordinate all utility shutdowns with the Contracting Officer's Representative (COR); and comply with all applicable federal, state, and local laws, regulations, standards, and codes. Work shall be coordinated with the COR to minimize impacts on daily operations at the VA Bedford Healthcare System. The award will be made as a firm-fixed-price purchase order. Offers are due by 3:00 PM EDT on May 11, 2026.
https://sam.gov/workspace/contract/opp/2e591e76874d4ec9b40bcffa1e461985/view

F -- EIGHTEEN MILE CREEK SATOC (SOL) [Market/Commercialization]

Thu, 7 May 2026 13:54:45 GMT

U.S. Army Corps of Engineers, Northwestern Engineer Division, Kansas City District, Kansas City, MO
Contract Opportunities on SAM.gov W912DQ26RA031, 2026

This is a total small business set-aside under NAICS code 562910. The U.S. Army Corps of Engineers, Northwestern Engineer Division, requires recurring remedial action efforts at the Eighteen Mile Creek Superfund Site, Operable Unit 1 (OU1), OU2, and OU4, in Niagara County, New York. The overall objective is to perform excavation and transportation, and disposal of lead-contaminated soil that exceeds the Record of Decision (ROD) specified cleanup levels. The award will be a Single Award Task Order Contract (SATOC). The SATOC will provide the Government with a continuity of personnel and institutional knowledge for developing a streamlined response and flexible vehicle for cost-effective soils remediation. It may require, but is not limited to, designs, interim actions, remedial actions, short-term operation and maintenance, laboratory management, reports, and any other actions necessary to implement the soils remedy at the site. Offers are due by 2:00 PM CDT on May 26, 2026.
https://sam.gov/workspace/contract/opp/4eff4fc4f7df4fe6a51bfbfa6e21daed/view

ENHANCING HEAVY METAL REMOVAL USING NOVEL MEDIA SOLUTIONS [General News]

Tue, 28 Apr 2026 14:03:44 GMT

Boussoufa, I. | SMART Remediation, 20 January, Vancouver, Canada, 44 slides, 2026

Advanced treatment methodologies are introduced for the removal of heavy metals, specifically focusing on arsenic, lead, uranium, and mercury. Capabilities of the Cleanit media, a novel iron-based media that efficiently removes lead and arsenic via adsorption and precipitation processes, were presented. The effectiveness of Cleanit-LC in removing toxic heavy metals to meet ultra-low discharge limits was demonstrated, showcasing its potential to significantly reduce environmental impact without altering pH levels, thus promoting cleaner industrial practices at a much lower cost than specialized ion exchange resin. ChemSorb ML, an innovative and versatile amendment for mercury removal, was also covered. ChemSorb ML chemically binds various forms of mercury, including elemental, ionic, and methylmercury, achieving reductions of leachable mercury by >99% and lowering concentrations to parts-per-trillion levels, making it an effective solution for stringent compliance requirements. The presentation concludes with case studies, presentations, and performance data that illustrate the practical applications and benefits of these media in real-world scenarios, underscoring their effectiveness in reducing operational costs and enhancing compliance with environmental regulations. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver_Calgary-2026-%E2%80%93-Imane-Boussoufa.pdf

CURRENT KNOWLEDGE ABOUT PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS) IN THE ATMOSPHERE: FATE, ANALYTICAL METHODS AND RESEARCH PRIORITIES [General News]

Tue, 28 Apr 2026 14:03:25 GMT

Vieira, H.G., M.C. Canela, R.C. Urban, and B.S. Cabrero. | Chemosphere 389:144703(2025)

This comprehensive overview of the current knowledge on PFAS covers: (i) a compilation of information on emission sources, including primary sources (production, manufacturing, use of AFFF, waste handling, marine spraying) and secondary sources (oxidative degradation of neutral PFAS); (ii) proposed classifications of the volatility of these substances based on vapor pressure by EPA; (iii) atmospheric processes that govern gas-particle partitioning, long-range transport, and deposition; (iv) an assessment of current and emerging sampling and analytical techniques, including OTM 45/50 methods; and (v) the identification of priority knowledge gaps. Among the main existing gaps, the validation of improved monitoring strategies and inhalation toxicity studies for neutral precursors could significantly contribute to a robust risk assessment and support regulatory efforts within the evolving global agenda for the phase-out of PFAS.

MANAGEMENT OF CONCRETE AND ASPHALT CONSTRUCTION MATERIALS IMPACTED BY PFAS [General News]

Tue, 28 Apr 2026 14:02:56 GMT

Doudrick, K. and M. Pourghaz. SERDP & ESTCP Webinar Series, March 2026

This webinar highlights research on the management of concrete and asphalt materials impacted by PFAS, including the transport, leaching, and thermal treatment of PFAS and the potential for reusing treated materials. The first presentation discusses recent work focused on the comprehensive management of PFAS-impacted pavements. It features insights from experimental and modeling results of leaching experiments and overall implications for low-temperature thermal treatment of pavement and its reuse following treatment. For thermal treatment, PFAS degradation was investigated across a range of temperatures (400-1000°C) and residence times. Results showed that the natural or added presence of calcium hydroxide enabled >95% PFAS mineralization and >99.99% destruction and removal efficiency (DRE) at 500°C in under 5 minutes. The project also studied the leaching behavior of PFAS from pavements and examined the potential for reusing thermally treated aggregates. Findings support a multifaceted approach to managing PFAS-impacted pavements, balancing effective remediation, environmental protection, and material reuse. The second presentation discusses a project that investigates the mechanisms governing PFAS transport, interaction, and transformation in Portland cement concrete (PCC) and asphalt concrete (AC) to determine whether these materials serve as long-term sources of PFAS release. The research combined lab experiments and field studies to characterize PFAS distribution in impacted materials; quantify sorption, desorption, and transport processes under saturated and unsaturated conditions; and evaluate PFAS release through surface runoff under field-relevant conditions. Experimental results were used to develop practical transport models capable of translating standardized leaching test data into field-scale predictions for intact, damaged, and recycled materials. https://serdp-estcp.mil/resources/details/568b2bbd-73bb-4aec-816e-2158ae15694c/management-of-concrete-and-asphalt-construction-materials-impacted-by-pfas

AIRCRAFT RESCUE AND FIREFIGHTING VEHICLE CLEANING FOR AFFF REMOVAL [General News]

Tue, 28 Apr 2026 14:02:36 GMT

Lang, J. and D. Kay. SERDP & ESTCP Webinar Series, February 2026

This SERDP and ESTCP webinar features innovative approaches and technologies for PFAS removal and/or destruction from fire suppression systems impacted by residual PFAS due to the use of AFFF. The Department of War (DoW) has many fire suppression systems impacted by residual PFAS due to the use of AFFF. At elevated concentrations, PFAS self-assemble and coat surfaces at liquid/solid interfaces, forming waterproof coatings. Recent work demonstrated that water-only rinses may not adequately clean some system components. However, the cost of replacing all existing PFAS-impacted AFFF delivery infrastructure across DoW installations would be expensive and result in equipment downtime. The first presentation showcases insights from disassembling and analyzing PFAS residual content on foam system components from the Oshkosh T-1500 Aircraft Rescue and Firefighting vehicle. Results provide critical information on mission-relevant considerations for fully remediating equipment after baseline treatment, including costs for replacement of the on-board foam system, out-of-service time required for cleaning, and the extent of replacement required to successfully achieve PFAS removal from an on-board foam system. The second presentation features the PFASigator, a treatment unit that provides a practical, effective, and scalable solution for successfully remediating firefighting systems historically exposed to AFFF. Through employing a micelle?enabled photoactivated reductive defluorination reaction, the solution provides simultaneous PFAS desorption and destruction. The presentation shares results from a field demonstration performed at Tyndall Air Force Base, where PFASigator was connected to a decommissioned firetruck's AFFF tank and associated piping to form a closed recirculation loop. The integrated process of PFAS desorption and destruction removed and mineralized 16.8 grams of PFAS within 48 hours. https://serdp-estcp.mil/events/details/9efc643a-c67f-4035-872a-ae46cb7d0976/aircraft-rescue-and-firefighting-vehicle-cleaning-for-afff-removal

POWDERED ACTIVATED CARBON TREATMENT OF PFAS-CONTAINING WASHWATER FROM AIRCRAFT HANGAR PIPE RINSING [Research]

Tue, 28 Apr 2026 14:02:19 GMT

Hensley, J., J.D. Schober, M. Magnuson, and W.F. Harper.
Remediation 36(2):e70065(2026)

A study investigated the use of powdered activated carbon (PAC) to remove PFAS from washwater used to rinse pipes from aircraft hangar pipe contaminated with AFFF. The untreated washwater contained 249?µg/L of total PFAS. The concentrations were highest for 6:2 FTS (178?µg/L), PFHxA (48?µg/L), PFOA (9.5?µg/L), and PFPeA (6.2?µg/L). PFAS was removed from washwater during 24-h adsorption experiments conducted over a range of adsorbent masses. Temporal increases were observed between the 2- and 4-h total PFAS concentrations during most of the experiments, corresponding to some PFAS species being displaced during complex competitive adsorption mechanisms. After 24?h in the presence of 0.23?g of PAC per liter of solution, removals of 6:2 FTS and PFHxA, two of the short-chain PFAS, were 95% and 86%, respectively. For long-chain PFAS, PFOA, and PFOS were removed to below their quantitation limits in most cases. However, removal of 8:2 FTS was only 52% in the presence of 0.0575 grams of PAC, despite having a relatively high Log K_ow and dipole moment values, also pointing to the complexity of PAC adsorption mechanisms in AFFF contaminated water.

REMOVAL OF PAHS FROM LARGE-SCALE CONTAMINATED SOIL IN A BIOAUGMENTED SLURRY REMEDIATION SYSTEM: OPTIMAL CONDITIONS VERIFICATION, ENVIRONMENTAL PARAMETER MONITORING, AND MICROBIAL COMMUNITY ANALYSIS [Research]

Tue, 28 Apr 2026 14:02:02 GMT

Wang, F., J. Chen, X. Xiao, X. Wang, and S. Chen.
Bioresource Technology 439:133377(2026)

PAH removal was enhanced through a combination of bioaugmentation, condition optimization, and the addition of nitrogen sources and surfactants in a study using a fully functional bioaugmented slurry remediation system to provide a device template for remediation. The study investigated the effects of adding peptone or Tween-80 on PAH removal by agent NS4 in the system. Tween-80 addition under optimal conditions achieved a higher PAH removal efficiency than optimal conditions (with or without peptone addition). System monitoring showed that microbial growth, metabolism, and PAH biodegradation collectively reduced DO and pH while increasing EC. Monitoring these parameters can indirectly reflect microbial activity and PAH removal progress, offering new insights for onsite supervision of PAH remediation. Soil microbial communities differed significantly across environmental conditions. Environmental conditions and remediation time jointly influenced microbial community and functional succession, with environmental conditions exerting a stronger driving force. Network analysis identified 42 microbial operational taxonomic units and 16 PAH-degradation genes as key factors, revealing close interactions between soil microorganisms and PAH-degradation genes.

LABORATORY INVESTIGATION OF INADVERTENTLY GENERATED PCBS RELEASED FROM CONSUMER PRODUCTS INTO LAKE WATER [Research]

Tue, 28 Apr 2026 14:01:45 GMT

Frauenheim, M., X. Liu, K. Woodward, M.R. Mullin, B. Nickel, M. Aguilar, K. Philpott, and
E. Folk. | Journal of Hazardous Materials 503:140974(2026)

A study investigated the occurrence and leaching behavior of inadvertently generated PCBs (iPCBs) in consumer products, including children's toys, craft supplies, paints, soaps, and food packaging. Product selection prioritized items used by children and tribal communities where PCB exposure risks are of heightened concern. Using solvent extraction, sample cleanup processes, and gas chromatography/mass spectrometry analysis, 37-4,268?ng/g of PCB-11 was detected in seven of 114 product types tested and a total of 21 respective color variants. Highest concentrations were found in items containing orange pigments, supporting hypotheses linking PCB-11 to azo pigment synthesis. To assess environmental release potential, batch leaching tests were performed on four representative products across various leach durations (2-28 days) and liquid-to-solid (L/S) ratios (6.7-26.7?mL/g). Results showed that

A PROPOSED EFFECTIVE PRACTICE APPROACH FOR THE CHARACTERIZATION OF DNAPL SOURCE ZONES [Research]

Tue, 28 Apr 2026 14:01:22 GMT

Reynolds, D., K.G. Mumford, S. Bryck, B.H. Kueper, and M. Kavanaugh.
Groundwater Monitoring & Remediation 46(1):49-61(2025)

A study employed the results of a previous virtual site investigation to develop effective practice approaches (methods, strategies, or techniques that have been demonstrated through evidence or experience to yield positive results or outcomes that align with specific, pre-determined goals) for estimating DNAPL footprint and mass, referred to as the Bounding Box and Bulk Retention approaches, respectively. The accuracy and precision of the estimates were assessed using a stochastic approach applied to the virtual sites and evaluated against those by experienced practitioners. The accuracy of the DNAPL footprint and mass estimates did not depend strongly on the borehole density, but the precision of those estimates increased with increasing borehole density. This increase was more pronounced for DNAPL mass than for footprint (i.e., mass estimates were more precise than footprint estimates at the same borehole density), which suggests prioritizing DNAPL source zone delineation during site investigation. When estimates based on grid or random borehole locations were compared to estimates by an expert practitioner, expert judgment was beneficial at low borehole densities but resulted in similar estimates at higher densities, provided that effective practice was used. Estimates based on random borehole locations often outperformed those based on experienced judgment without effective practice, which highlights the importance of data analysis over borehole location for characterizing DNAPL source zones.

ADSORPTION OF ULTRASHORT-, SHORT-, AND LONG-CHAIN PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS): IMPACTS OF ADSORBENT, PFAS TYPE, AND COMPETITIVE IONS [Research]

Tue, 28 Apr 2026 14:01:04 GMT

Smith, S.M., A.X. Wu, T. Smrz, and L. Xiong. Chemosphere 395:144836(2026)

This study assessed the adsorption efficacy of commercially available anion exchange resin (AEXR) and granular activated carbon (GAC) adsorbents across a series of ultrashort-chain (USC), short-chain (SC), and long-chain (LC) PFAS, with an emphasis on the USC class. Results uncover the relative adsorption selectivity for AEXR vs GAC, the importance of the AEXR functional group, and the impact of competitive inorganic anions across different PFAS and adsorbents. A dynamic column test validated the capacity trends from batch adsorption testing in relation to bed volumes until breakthrough. The structure-property relationships identified expand on the fundamental understanding of adsorbent technology for PFAS remediation applications and highlight the challenges in expanding the application use case, particularly for USC PFAS remediation from water.

PFAS STABILIZATION: COMPREHENSIVE BENCH SCALE EVALUATION OF AMENDMENTS, DOSAGE, AND BINDERS [Research]

Tue, 28 Apr 2026 14:00:50 GMT

Torney, K. | SMART Remediation, 20 January, Vancouver, Canada, 22 slides, 2026

A bench scale study evaluated a combination of stabilizers and binders to provide a more comprehensive, comparative review of amendment and help inform remediation planning at a site with AFFF-impacted soil. Bench scale testing was conducted on soil collected from the site. The study included three stabilizers (proprietary and generic) at four dose percentages (0.2%, 0.5%, 1%, and 2.0% dry weight) with or without binder for a total of 26 mixes, including control samples. The study was designed to report a four-point (plus unamended reference) dose response relationship for each mix and be consistent with the minimum testing regime for similar peer-reviewed published studies. The testing regime included compaction, hydraulic conductivity testing, geotechnical analyses, EPA LEAF 1314 and 1315, low-level liquid chromatography mass spectrometry, total oxidizable precursor assay (TOPA), and Synthetic Precipitation Leaching Procedure for comparison to LEAF methods. Results informed the following testing objectives: 1) relative performance of proprietary and non-proprietary amendments at varying dosages; 2) dosage/quantity of amendment required to meet site-specific remediation targets; 3) effectiveness of binders to enhance stabilization performance; and 4) comparison of leaching methods. Additionally, geotechnical and hydraulic conductivity data were used to interpret leaching results and were also assessed for potential field-scale quality control, and TOPA data were assessed to determine amendment activity with respect to precursors. Study results contribute to the PFAS soil amendment efficacy literature and can assist in decision-making with respect to amendments, leaching/analytical approaches, implications, and field implementation. Use of amendments to mitigate PFAS contamination represents a sustainable option that reduces soil landfilling and minimizes transportation-related emissions. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver-2026-%E2%80%93-Korene-Torney.pdf

FACILITATED TRANSPORT OF ORGANIC CONTAMINANTS IN A HIGH CONCENTRATION, MULTICOMPONENT PLUME [Demonstrations]

Tue, 28 Apr 2026 14:00:29 GMT

Mackay, D.M., B. Myller, G.C. Bianchi-Mosquera, B.D. Honeyman, M. Schirmer, R.M. Allen-King, W.P. Ball, and R.L. Stollar. Groundwater Monitoring & Remediation 46(1):62-83(2026)

A field experiment evaluated the transport of organic contaminants in a plume from hazardous waste disposal areas at the Rocky Mountain Arsenal. The plume contained many xenobiotic contaminants with widely varying expected mobilities. In lab tests, aquifer sediments showed significant capacity for sorption of organic contaminants from synthetic groundwater, suggesting contaminants' mobilities in situ could have been retarded. Sediment cores showed sorbed concentrations of contaminants at or below detection levels, suggesting sorption in situ was minimal. The field experiment made direct observations of organic contaminant transport under plume conditions by flushing tracer-amended organic-free water through the plume. No contaminants were retarded in their migration compared to the tracer, suggesting negligible sorption of the contaminants in situ. The concentration of colloids, cosolvents, and anionic surfactants in the plume was too low to have had a significant effect on contaminant migration. Though not monitored, non-ionic surfactants could have reduced sorption somewhat if they had constituted a significant fraction of the uncharacterized dissolved organic carbon. Though monitored only indirectly, micro- or nano-plastic particles were deemed unlikely to have significantly affected organic solute transport. Microemulsions may have been present and facilitated the transport of contaminants, but only indirect evidence was obtained. Although the specific reasons for the enhanced mobility of organic contaminants could not be confirmed, the study showed that unknown plume components can be responsible for the suppression of sorption, suggesting new lab research is needed to expand understanding of factors affecting sorption. https://ngwa.onlinelibrary.wiley.com/doi/epdf/10.1111/gwmr.70028

COLLOIDAL ACTIVATED CARBON PERMEABLE REACTIVE BARRER TO REDUCE PFAS MIGRATION FROM IMPACTED GROUNDWATER INTO OAKLAND BAY [Demonstrations]

Tue, 28 Apr 2026 13:59:13 GMT

Nunez, D. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 21 slides, 2026

PFAS concentrations, ranging from 7.6 to >300,000 ng/L, were detected in groundwater at Alameda Point (Former Naval Air Station Alameda) from past use of AFFF at Site 14. A large-scale pilot test is underway to test the effectiveness of an in situ colloidal activated carbon (CAC) barrier at reducing the mass flux of PFAS migration into Oakland Harbor. The 720-foot PRB was designed using results from a pre-field mobilization lab test using flow-through column tests and contaminant mass flux studies, with 2%, 5%, and 7% CAC dosages. Post-application monitoring over three consecutive quarters shows significant PFAS reduction across three transects along the PRB:

Transect 1: Upgradient well (10 ft.) reductions ranged from -10% to 53%, downgradient PRB edge well reductions ranged from 97% to 99%, and downgradient well (17 ft.) reductions ranged from 88% to 99%.

Transect 2: Upgradient well (18 ft.) reductions ranged from -9.2% to 90%, downgradient PRB edge well reductions ranged from 98% - 99%, and downgradient well (18 ft.) reduction ranged from 46% - 79%.

Transect 3: Upgradient well (14 ft.) reductions ranged from 20%-52%, downgradient PRB edge well reductions ranged between 62% - 99%, and downgradient well (18 ft.) reductions ranged between 68% - 89%.

https://mediacdn.guidebook.com/upload/213718/FuIbQVugUYxtCATmDmxNTZvZi2ORX63cxriX.pdf

PILOT SCALE TREATMENT OF PFAS-CONTAMINATED GROUNDWATER IN A SUBSURFACE FLOW CONSTRUCTED WETLAND-EVALUATING MULTIPLE PLANT SPECIES [Demonstrations]

Tue, 28 Apr 2026 13:58:52 GMT

Liljestrom, O., D. Rosenquist, D.B. Kleja, A. Enell, and L. Ahrens.
Environmental Pollution 386:127199(2025)

Subsurface flow constructed wetlands were investigated for treating PFAS-contaminated groundwater. The wetlands used a peat, biochar, and lightweight expanded clay aggregate filter substrate, planted with either tufted sedge (Carex elata), fiber hemp (Cannabis sativa Futura 75), or an intercropping of the two Salix clones S. Wilhelm and S. Loden. The experiment was conducted under field conditions in Sweden during one growing season using PFAS-contaminated groundwater impacted by landfill leachate. PFAS accumulated in all plant species and the peat and biochar part of the filter substrate, with short-chain PFAS and PFCAs dominating when considering the whole plants (57% and 77% of ∑PFAS, respectively) and long-chain PFAS and PFSAs dominating in the peat and biochar filter substrate (77% and 54% of ∑PFAS, respectively). Sorption to the filter substrate was the primary mechanism for PFAS removal. The highest plant PFAS concentrations were found in leaves, followed by roots, for all species. A difference in the PFAS composition profile was found when comparing different plant tissues, with PFCAs dominating in leaves (84% of ∑PFAS) and PFSAs dominating in roots (66% of ∑PFAS). All plant species had an above-ground tissue/water phase concentrations >10/1 for C3-PFCA (PFBA). This was also observed for C. sativa with C4- and C7-PFCAs (PFPeA, PFOA), and C4- and C5-PFSAs (PFBS, PFPeS), for C. elata with C8-PFSA (L-PFOS), and for S. Loden with PFPeA. ∑PFAS phytoextraction potential from landfill leachate-impacted groundwater (mg/ha yr) was estimated to be 940 ± 670 for C. sativa, 390 ± 310 for S. Loden, 330 ± 160 for S. Wilhelm, and 160 ± 56 for C. elata. https://www.sciencedirect.com/science/article/pii/S0269749125015738/pdfft?md5=abeaf3db92a84b10bdc3258c4a524c64&pid=1-s2.0-S0269749125015738-mainext.pdf

RA CASE STUDY EPA REGION 5, VELSICOL CHEMICAL CORPORATION SUPERFUND SITE RES CLIN 2 – OU1 DOWNGRADIENT VERTICAL BARRIER WALL (DGVBW) CONSTRUCTION, ST. LOUIS, MICHIGAN [Cleanup News]

Tue, 28 Apr 2026 13:57:40 GMT

Srirangam, R. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 20 slides, 2026

The Downgradient Vertical Barrier Wall (DGVBW) Construction Project at the Velsicol Chemical Corporation Superfund Site provides a compelling case study in highlighting significant construction challenges that are overcome with structured adaptive management strategies. The presentation explores topics implemented to overcome remedial action challenges while constructing the DGVBW, a 4,300-ft-long sealed steel combination sheet-pile and cylindrical king-pile containment wall installed ~30-ft deep into the subsurface of the Pine River. The DGVBW was designed as a source control remedy to intercept potential subsurface migration of DNAPL and dissolved-phase contaminants into Pine River. Key to the project's success was implementing adaptive management strategies to address design requirements and associated changes and incorporate stakeholder feedback promptly to stay on schedule. The framework enabled rapid decision-making and alignment among regulators, while maintaining compliance with all project requirements. The adaptive management process included field verification of existing site conditions, constructability reviews enabling design modifications, and planning activities to resolve technical uncertainties. A multi-tiered communication strategy included weekly construction, agency, and interagency coordination meetings, onsite briefings, drone aerial imagery to review existing and changing site conditions, reviewing real-time digital monitoring of dust, noise, turbidity, water level changes, and seismic data during construction, and public engagement sessions that helped maintain transparency. The presentation highlights construction challenges that were overcome while working near a sensitive residential setting. This case study provides insights into lessons learned for managing large-scale remedial action with high community visibility. It also underscores the importance of strategic communication, adaptive management, and cross-agency collaboration in delivering technically sound and publicly supported outcomes. https://mediacdn.guidebook.com/upload/213718/KvcWyQ92097h13KSPqigw6PDVJCUDxyQWjEx.pdf

A HOLISTIC APPROACH TO SITE REMEDIATION: A DECADE OF INTEGRATED IN SITU REMEDIES FOR MULTIPLE AOCS IN A COMMERCIAL SETTING [Cleanup News]

Tue, 28 Apr 2026 13:57:14 GMT

Srirangam, R. | DCHWS West 2025 Winter Symposium, 26-28 January, Denver, CO, 16 slides, 2026

Over the past decade, a holistic site remediation strategy was implemented to manage 54 areas of concern (AOCs) at a commercial site in the Northeastern U.S. impacted by contaminants ranging from VOCs and PAHs to PCBs and heavy metals. Remedial activities completed included the excavation of PCBs, SVOCs, and radiologically impacted soil to address 18 of the AOCs, in situ thermal remediation of a 3.1-acre area, removing 34,000 lbs of VOCs, ISCO of VOC-impacted soil and groundwater in a secondary 1.2-acre area, and the dredging of sediments within a downgradient drainage ditch. Engineering controls, including environmental capping and institutional controls, were established across the site with site redevelopment to limit human exposure, ensuring long-term efficacy and regulatory compliance. Following aggressive technologies like in situ thermal and chemical oxidation, the shift towards enhanced in situ bioremediation (EISB) and in situ biogeochemical transformation (ISBGT) was initiated based on long-term groundwater monitoring data demonstrating a shift toward naturally reducing conditions. A biobarrier was installed to prevent plume migration beyond the immediate source areas. EISB's application of organic substrates catalyzed microbiologically driven processes to further degrade residual contaminants. The barrier was optimized using ISBGT, which facilitated the transformation of existing geochemical conditions to create reactive minerals for accelerated monitored natural attenuation. The presentation demonstrates the significance of a holistic approach in managing complex contaminant profiles and the pivotal role of a comprehensive post-monitoring strategy in guiding and fine-tuning remedial transitions, leading to successful multi-faceted site restoration. https://mediacdn.guidebook.com/upload/213718/wOw0xhkbzPs8Z2LRLydn0hkBz4CM2Z4ErKsf.pdf

BUGS TO THE RESCUE: BUILDING A BIOBARRIER FOR MANAGING CVOC-IMPACTED GROUNDWATER [Cleanup News]

Tue, 28 Apr 2026 13:56:49 GMT

Patel, P. | SMART Remediation, 20 January, Vancouver, Canada, 20 slides, 2026

A study investigated the feasibility of a biobarrier system leveraging bacterial communities and solid organic carbon substrates. The approach aimed to provide a sustainable, cost-effective alternative to overcome the high upfront and replacement costs associated with zero-valent iron (ZVI) permeable reactive barriers (PRBs), while effectively managing highly impacted groundwater. The bench-scale study used readily available and cost-effective solid carbon substrates such as sawdust and peat. Batch microcosm, flow-through column studies, and column experiments demonstrated that peat supported complete reductive dechlorination of TCE to ethene, while sawdust stalled at cDCE and produced excessive methane. Gene analysis indicated that peat microcosms fostered higher populations of Dehalococcoides and functional vcrA genes, correlating with superior TCE degradation performance. Findings identified peat as the preferred substrate for biobarrier implementation and a full-scale biobarrier was constructed, spanning 125 m (410 ft) in length and 5.5 m (18 ft) in depth. The biobarrier achieved substantial CVOC reductions, including average reductions of 70% and localized reductions of up to 90% within two years of operation. Provisions were made for future injections of liquid-based carbon substrates to boost performance or replenish the solid substrates if needed. Over a five-year monitoring period, the biobarrier achieved a 97% reduction in contaminants without requiring maintenance or additional substrate injections. Findings provide valuable insights into substrate selection and system optimization, enabling effective and sustainable long-term groundwater remediation in challenging conditions. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Toronto-2026-%E2%80%93-Paresh-Patel.pdf

CERCLA REMOVAL ACTION AT MOJAVE NP, CA (SOL) [Market/Commercialization]

Tue, 28 Apr 2026 13:56:17 GMT

U.S. Department of the Interior, National Park Service, Washington Contracting Office
Contract Opportunities on SAM.gov 140P2126Q0049, 2026

This is an Indian Small Business Economic Enterprise (ISBEE) set-aside under NAICS code 562910. The U.S. Department of the Interior, National Park Service seeks a contractor to perform a Non-Time Critical Removal Action under CERCLA at the Hidden Hill Mine site within Mojave National Preserve, CA. The site is a small, remote abandoned mine covering 5 acres at an elevation of ~3,400 feet. Work includes removing approximately 69 cubic yards (CY) of commingled tailings and potentially affected underlying soil (assumed 1-foot depth) over approximately 1,850 square feet, including ancillary soils that may become commingled during excavation. The total estimated removal is 100 CY (150 tons using 1.5 tons/CY). The scope also includes preparing post-award plans, characterizing material, transporting it to approved disposal, collecting/analyzing confirmation samples, and preparing a Response Action Completion Report (RACR). Estimates are based on prior site investigations. The firm-fixed-price contract combines lump-sum and unit-priced items, subject to the variation in quantity clause, with an established ceiling and notification requirements. A 100% payment bond, 100% performance bond, and liability insurance are required before performance. A group site visit is scheduled at 10:00 AM on April 9, 2026. Attendance is strongly encouraged but not mandatory; individual site visits will not be accommodated. Offers are due by 3:00 PM PDT on May 5, 2026. https://sam.gov/workspace/contract/opp/25038d92ad9245159df111010adc4191/view

COMPREHENSIVE UTILIZATION OF IRON ORE TAILINGS: A REVIEW OF SUSTAINABLE PRACTICES AND TECHNOLOGIES [General News]

Thu, 9 Apr 2026 16:36:49 GMT

Wu, W., K. Kang, Q. Ye, A. Luo, J. Zhang, J. Wang, and S. Shi.
Mining, Metallurgy & Exploration 43:413-430(2026)

This paper reviews the physicochemical properties of iron ore tailings (IOT), analyzes the environmental hazards associated with their accumulation, and summarizes recent advancements in their comprehensive utilization, including recovering valuable elements, preparing backfill materials, developing construction materials, synthesizing soil conditioners, and producing chemical materials such as adsorbents and catalysts. Despite the promising pathways, the transition from lab research to industrial application faces challenges related to economic viability, process standardization, and long-term environmental safety. Future research should focus on developing low-cost activation technologies, enhancing the long-term durability and eco-efficiency of IOT-derived products, and integrating policy-driven incentives to promote market adoption. The review aims to provide a scientific basis and strategic reference for the high-value, sustainable utilization of IOT in the context of a circular economy.

DISPERSED ALKALINE SUBSTRATE PASSIVE TREATMENT TECHNOLOGY FOR HIGHLY CONTAMINATED ACID MINE DRAINAGE: 20 YEARS OF SUCCESSFUL APPLICATION [General News]

Thu, 9 Apr 2026 16:36:34 GMT

Leon, R., R. Millan-Becerro, F. Macias, C.R. Canovas, C.M. Neculita, C. Ayora and J.M. Nieto. Water Research 288(Part B):124683(2026)

Over the past two decades, Dispersed Alkaline Substrate technology (DAS) has emerged as a highly effective passive approach to treating acid mine drainage with extreme acidity and metal loading. DAS systems maintain high porosity and neutralization capacity without rapidly clogging by mixing alkaline materials (limestone, magnesia, barium carbonate, or industrial by-products) into an inert wood-chip matrix. The technology evolved from lab trials to pilot and full-scale field testing, using multi-step systems integrated with Natural Fe-Oxidizing Lagoons (NFOL) for pre-oxidation, which have demonstrated their long-term effectiveness for acidity and metal removal. The sustainability and applicability of the process have been improved by the search for new reagents (e.g., MgO for divalent metals removal, BaCO? for sulfate removal, wood ash or calcite-rich waste for cost reduction). Field trials in diverse regions, from the Iberian pyrite belt to South Africa, Canada, South America, Asia, Europe, and Oceania, report net acid removal often exceeding 95% and near complete retention of metal(loid)s such as Al, Cu, Zn, Pb, and As. Mineralogical analyses indicate that contaminants precipitate primarily as hydroxides, oxyhydroxides, and sulfates (e.g., schwertmannite, basaluminite, barite), allowing targeted valorization of metal-rich sludges. Remaining challenges include assessing long-term reagent life under variable hydrological conditions, extending full-scale use to phosphogypsum and other industrial leachates, and developing strategies for residue stabilization and resource recovery. This review aims to synthesize these developments, assess current performance, and identify future research needs for the advancement of passive DAS treatment technology.

WASTE GAS CAPTURE FROM ABANDONED MINES [General News]

Thu, 9 Apr 2026 16:36:13 GMT

Bobsein, B. 27th Annual PA AMR Conference, 14-16 October, State College, PA, 47 minutes, 2025

Mines vent methane out of the workings for safety purposes, but little is being done to capture this resource and utilize it. Today, waste methane from mines is predominantly being vented as a potent greenhouse gas, continuing for decades after a mine has been inactivated or abandoned. This energy source can be harnessed while furthering economic development in Pennsylvania, and in other industrial communities across the U.S. A project was pioneered to capture waste methane from abandoned mines and bring it to market as Remediated Mine Gas (RMG), one of just three such RMG operations in the U.S. EPA identified over 60 RMG project opportunities from abandoned mines, which could lead to thousands of jobs and billions of dollars in economic output. If leveraged correctly, RMG projects can lead to additional energy infrastructure being built out, getting reliably dispatchable fuel to market, improving grid resilience, lowering greenhouse gas emissions, and driving manufacturing and AI investment to these underserved areas. https://www.youtube.com/watch?v=nLZW9XXA2QM

PROACTIVE MINE POOL MANAGEMENT: IMPLEMENTING A REMOTE TELEMETRY MONITORING NETWORK IN PENNSYLVANIA'S BITUMINOUS DISTRICT [General News]

Thu, 9 Apr 2026 16:35:54 GMT

May, S. 27th Annual PA AMR Conference, 14-16 October, State College, PA, 43 minutes, 2025

Pennsylvania's Department of Environmental Protection's Bureau of Abandoned Mine Reclamation is initiating a long-term monitoring program to address the challenges posed by deep mine pools in the bituminous district. The mine pools, remnants of extensive historical coal mining, present significant risks of blowouts, subsidence, and other adverse environmental impacts if left unmanaged. An innovative network of monitoring wells equipped with remote telemetry systems is being established to enhance proactive readiness and improve mitigation strategies. The technology will provide real-time data on water levels, pressure changes, and other critical parameters, enabling immediate response to fluctuations indicative of potential hazards. The program aims to develop a robust dataset to predict trends and model behaviors within the interconnected mine pool systems. By integrating these monitoring efforts with geospatial analysis and predictive modeling, the initiative seeks to bolster the state's ability to anticipate and prevent catastrophic events. The presentation outlines the program's design, early implementation steps, and the broader implications for mine pool management. Attendees gained insights into leveraging advanced telemetry for sustainable reclamation practices and enhancing community and environmental resilience in areas impacted by legacy mining activities. https://www.youtube.com/watch?v=xjje3m0Shb8

DEPTH-DEPENDENT HETEROGENEITY IN TOPSOIL STOCKPILES INFLUENCES PLANT-MICROBE INTERACTIONS AND REVEGETATION SUCCESS IN ARID MINE RECLAMATION [Research]

Thu, 9 Apr 2026 16:35:24 GMT

Murawska-Wlodarczyk, K., P. Kushwaha, O. Stokes, C. Rasmussen, J.W. Neilson, R.M. Maier and A. Babst-Kostecka. Science of The Total Environment 1003:180673(2025)

A study evaluated soil health parameters within the 28-meter depth profile of a 14-year-old copper mine topsoil stockpile to identify key indicators of revegetation success in a semi-arid ecosystem. Plant growth was monitored using non-invasive root phenotyping in rhizoboxes filled with soils collected from different depth layers, allowing assessment of how biochemical variability in stockpiled materials influences germination and early establishment. Machine learning models integrating soil properties, plant responses, and sequenced soil bacterial/archaeal and fungal DNA identified key indicators influencing plant performance. Results revealed significant heterogeneity in soil quality across depths, with distinct biochemical and microbial profiles shaping vegetation establishment. The upper 10 m exhibited greater potential for supporting growth, with seedling survival reaching 95%, whereas deeper layers showed drastically reduced survival, sometimes as low as 0%, due to microbial shifts to anoxic conditions and elevated Fe and Mn toxicity. Fungal communities played a dominant role in germination, while archaea were more influential during later plant establishment. Soil parameter comparisons before and after the experiment indicated recovery processes initiated by plant-soil feedback, including fungal community renewal. Findings highlight the role of stockpile formation in preserving soil health attributes critical for ecological recovery and provide practical insights for optimizing land reclamation in semi-arid ecosystems. https://www.sciencedirect.com/science/article/pii/S0048969725023137/pdfft?md5=bb42e8e16ab1043283ec6bc06042c0d5&pid=1-s2.0-S0048969725023137-main.pdf

EVALUATION OF BOREAL PLANT AND MICROBE COMMUNITIES ON TAILINGS SOLVENT RECOVERY UNIT (TSRU) TAILINGS: A MESO-SCALE GREENHOUSE STUDY [Research]

Thu, 9 Apr 2026 16:35:07 GMT

Degenhardt, D., A. Van Dongen, A.-l. Balaberda, D.A. Escolastico-Ortiz, and C. Martineau.
Chemosphere 387:144662(2025)

A study evaluated the ability of Tailings Solvent Recovery Unit (TSRU) tailings to support upland and wetland vegetation under various thin capping designs using peat mineral soil mix (PMM) and coarse sand tailings (CST). A 30 cm PMM cover cap successfully supported upland and wetland vegetation for three years, while a thicker, multi-layer cap of 30 cm PMM above 20 cm of CST further improved plant survival and growth. The cap was found to effectively act as a barrier, protecting vegetation from the adverse effects of pyrite oxidation in the TSRU tailings. While the TSRU tailings acidified (pH ≤ 2) under all capping treatments, the thickest cap (30 cm PMM/20 cm CST) delayed acidification by one year. TSRU and CST had low microbial biomass and diversity, with bacterial communities mostly composed of sulfur oxidizers and acidophilic taxa. In contrast, the PMM layer maintained a higher microbial biomass, diversity, and stability across all treatments, highlighting its potential to enhance plant-microbe interactions and improve the reclamation success of TSRU tailings. https://www.sciencedirect.com/science/article/pii/S0045653525006101/pdfft?md5=e1a1ae4715a1549a7f84720ff3f5669c&pid=1-s2.0-S0045653525006101-main.pdf

ASSESSMENT OF BIOCHAR, COMPOST, AND IRON AMENDMENTS TO ENHANCE THE PHYTOSTABILISATION OF ARSENIC IN GOLD MINE WASTE BY THE AUSTRALIAN NATIVE PLANT SPECIES POA LABILLARDIERI (STEUD.) [Research]

Thu, 9 Apr 2026 16:34:49 GMT

Besedin, J.A., L.S. Khudur, D.A. Besedin, P. Netherway, A.L. Juhasz, A. Batra, F. Huslina, S.K. Biek, G. Aguilar, and A.S. Ball. Chemosphere 391:144728(2025)

A greenhouse mesocosm experiment was conducted for 100 days to optimize phytostabilization using P. labillardieri with soil amendments, 5% biochar, 5% compost, and 1% ferric oxide (Fe₂O₃), applied individually or in combination. The combined treatment of 5% biochar and 5% compost (BC) significantly (p ≤ 0.01) increased root As concentrations (657 ± 135 mg/kg) compared to the unamended control (317 ± 12 mg/kg). Shoot As concentrations ranged between 30 and 44 mg/kg for all treatments. The BC treatment increased soil-to-root bioaccumulation to 0.97, 1 being optimal for phytostabilisation. Soil As concentrations significantly decreased (677 ± 21.5 mg/kg) compared to the unamended control (781 ± 6.32 mg/kg). In addition, As removal from soil improved from 6.83 ± 5.93 to 50 ± 24 mg/m³, and in vitro bioaccessibility decreased from 47.0 ± 6.92 to 35.8 ± 0.72%. The BC treatment had greater root (0.01 ± 0.01 g), shoot (0.05 ± 0.02 g), and total biomass (0.06 ± 0.03 g), compared to the control (0.004 ± 0.002 g root biomass; 0.01 ± 0.01 g shoot biomass; 0.014 ± 0.012 g total biomass). The BC treatment shows potential to assist phytostabilisation using P. labillardieri. A field trial is recommended using the newly developed phytostabilization technique to validate the results under natural climatic conditions.

PHYTOREMEDIATION STRATEGIES FOR THE RECLAMATION OF TAILINGS AND MINING SOILS IN AN ACTIVE OPEN-PIT SITE [Research]

Thu, 9 Apr 2026 16:34:16 GMT

Diaz, A.M., R. Forjan, J.L.R. Gallego, L. Benavente-Hidalgo, A. Sanchez-Poyal, P. Diaz-Garcia, J.M. Menendez-Aguado and D. Baragano.
Environmental Research 275:121464(2025)

Two phytoremediation strategies were evaluated at an active open-pit mining site within a dunite deposit, an ultramafic igneous rock rich in nickel. Strategies included phytostabilization for tailings and phytoextraction for mining soil, composed of natural soil aggregates mixed with fine dunite fragments. Tailings had an alkaline pH (8.8), low organic matter content (9.4 g/kg), and high available Ni concentrations, requiring immobilization using compost, vermicompost, biochar, and vermichar. Amendments were tested in 1-kg pots over 180 days, assessing soil properties, plant growth, and Ni accumulation in Lolium perenne L. Mining soil showing a more neutral pH (7.6), higher organic matter (106 g/kg), and high available Ni contents underwent phytoextraction supported by EDTA and citric acid in a parallel experiment. Phytostabilization with compost, vermicompost, and vermichar significantly reduced available Ni (<5 mg/kg), improved plant growth, and increased labile carbon, while biochar was less effective. Vermicompost proved particularly beneficial, enhancing nutrient and carbon availability, minimizing Ni leaching, and preventing excessive accumulation in plant aerial parts. Phytoextraction was successfully implemented without altering soil properties, with EDTA boosting Ni accumulation in aerial biomass up to 400 mg/kg, outperforming citric acid. Findings highlight the adaptability of phytoremediation, demonstrating the successful application of both strategies in the same environment, with Lolium perenne L. functioning either as a metal accumulator or a phytostabilizing plant depending on the amendments used. https://www.sciencedirect.com/science/article/pii/S0013935125007157/pdfft?md5=0d1c4144fcf31a18f4d03b4a7e8b125f&pid=1-s2.0-S0013935125007157-main.pdf

FACTORS INFLUENCING WATER QUALITY IN SURFACE WATER AND ALLUVIAL GROUNDWATERS DOWNGRADIENT OF A RECLAIMED SURFACE COAL MINE IN THE POWDER RIVER BASIN OF SOUTHEASTERN MONTANA, USA [Research]

Thu, 9 Apr 2026 16:33:55 GMT

Keeshin, S.I., S.A. Ewing, E.B. Meredith, R.A. Payn, and A. Hunt.
Hydrogeology Journal 33:715-737(2025)

Geochemical trends in water quality were evaluated downgradient of a fully reclaimed landscape at the former Big Sky Mine in the Rosebud Creek watershed over 3 years, including bond release in 2022. Within 6 km downgradient from the reclaimed area, sulfate concentrations decreased from ~3,500 to 1,800 mg/L within the Miller Coulee alluvial aquifer. Major ions, ?34SSO4 values, and residence time tracers suggest that the observed decreases in sulfate concentration result from a combination of dilution by mixed-age inflows and incomplete transit of the high salinity plume from the mine boundary. Bedrock and alluvial aquifers of the Rosebud Creek corridor contained contributions of millennia-old regional groundwater, which may serve to mitigate mine-derived high-salinity waters. Rosebud Creek, which traverses the outflow zone of Miller Coulee in the study area, exhibited high sulfate concentrations during low flows and consistent downgradient increases in sulfate concentration. The possibility of plume dynamics in Miller Coulee suggests that the greatest water quality impacts may not yet have reached Rosebud Creek. This article is Open Access at https://link.springer.com/article/10.1007/s10040-025-02898-z

SOURCE APPORTIONMENT OF LEAD IN THE SAN JUAN WATERSHED (USA): INFLUENCES FROM WEATHERING OF MINERALIZED AND SEDIMENTARY DEPOSITS [Research]

Thu, 9 Apr 2026 16:33:39 GMT

Wilkin, R.T., M.R. Noerpel, M. Rovero, L. Costantino, I. Bowen, and C. Larrick.
ACS Environmental Au 5:583-593(2025)

A study examined the sources and distribution of Pb within the San Juan watershed in southwestern Colorado and the Four Corners region (Colorado, New Mexico, Arizona, and Utah). Samples collected from 2018 to 2021 included seeps and springs located within the mineralized headwaters region, surface water, and sediments along an ~570 km stretch of riverbed. Concentrations and isotopic compositions of Pb showed that source attribution using stable Pb isotope ratios (²⁰⁶Pb/²⁰⁴Pb, ²⁰⁷Pb/²⁰⁴Pb, and ²⁰⁸Pb/²⁰⁴Pb) facilitated analysis of metal dilution and changing Pb sources. In upstream reaches, Pb from landscape disturbance related to mining operations and weathering of mineralized geologic units represented the most significant Pb source, accounting for as much as 90% of the Pb within upper Animas River sediments. Pb attributed to the mining-impacted headwaters decreased downstream through the Animas River and San Juan River and represented up to about 50% of the Pb in downstream sediments. The proportion and mass of Pb derived from the mining district were reduced in downstream areas due to increased sediment delivery to the central river channels from tributaries and weathering of Paleozoic- to Tertiary-aged sedimentary deposits. Analysis demonstrates that Pb isotope ratios can be used to effectively trace Pb transport through watershed systems where multiple Pb sources exist and where Pb concentrations may be similar to geogenic values. Results indicate that the spatial and temporal variation of Pb isotopic signatures is associated with multiple contributions from natural sources, which are influenced by seasonality and hydrological factors. https://pubs.acs.org/doi/pdf/10.1021/acsenvironau.5c00070?ref=article_openPDF

PERFORMANCE OF PILOT-SCALE PASSIVE TREATMENT TESTS OF A CONTACT OXIDATION MANGANESE-OXIDIZING BACTERIA FOR MANGANESE-CONTAINING MINE WATER [Demonstrations]

Thu, 9 Apr 2026 16:33:24 GMT

Semoto, Y., T. Hamai, Y. Masaki, M. Ikeda, M. Okumura, N. Miyata, T. Yasutaka, and T. Katayama. Proceedings from the International Mine Water Association Conference, 7-11 July, Braga, Portugal, and Oviedo, Spain, 7-11 July, 2025

A pilot study evaluated the performance of a pilot-scale passive treatment system consisting of a limestone bioreactor and a fiber filter material bioreactor in series and employing a contact oxidation method utilizing Mn-oxidation bacteria for neutral mine water containing Mn and Zn over approximately one year of operation. In the limestone bioreactor, the maximum Mn removal rate reached 49.7 g/m³/day under aeration at water temperatures of ~20°C. Even under low water temperatures of around 5°C, the average Mn removal rate of the system reached 5.65 g/m³//day at a hydraulic retention time of 3 days in a limestone bioreactor. https://www.imwa.info/docs/imwa_2025/IMWA2025_Semoto_874.pdf

THE EVALUATION OF A PILOT PERVIOUS CONCRETE TREATMENT SYSTEM FOR ACID MINE DRAINAGE TREATMENT [Demonstrations]

Thu, 9 Apr 2026 16:33:06 GMT

Shabalala, A., M. Ngomane, and N. Khanyile.
Proceedings from the International Mine Water Association Conference, 7-11 July, Braga, Portugal, and Oviedo, Spain, 7-11 July, 2025

A pervious concrete (PERVC) reactive barrier system was designed and evaluated to remediate AMD at an abandoned coal mine site. Following treatment with PERVC, the pH increased from 2.6 to 12. Al, Fe, Zn, Ni, Co, Cu, and Mn were effectively removed from the mine water with efficiency levels of 97% to 100%. PERVC offers alternative technology for contaminated mine waters that can be used for full-scale implementation. https://www.imwa.info/docs/imwa_2025/IMWA2025_Shabalala_880.pdf

EVAPOTRANSPIRATION COVER DESIGN OPTIMIZATION – A CASE STUDY [Demonstrations]

Thu, 9 Apr 2026 16:32:50 GMT

Subotskaya, Y. and L. Breckenridge.
Proceedings from the International Mine Water Association Conference, 7-11 July, Braga, Portugal, and Oviedo, Spain, 7-11 July, 2025

A new evapotranspiration (ET) cover was designed, field-tested, and optimized with computer modeling for the tailings storage facility at the Zangazeur Copper-Molybdenum Complex in Kapan, Armenia. Field data collected from ET cover test cells, soil characteristics, and climate data were combined to create a variably saturated groundwater flow model, which simulated the effectiveness of the cover for more than 10 years. The model was validated against the field-observed measurements of moisture. A minimum cover thickness is recommended to prevent breakthrough. https://www.imwa.info/docs/imwa_2025/IMWA2025_Subotskaya_897.pdf

BIOACCUMULATION OF ARSENIC IN MINE WASTE CONTAMINATED SOIL USING POA LABILLARDIERI++998 (STEUD.) AND SOIL AMENDMENTS: A SHORT-TERM PILOT TRIAL [Demonstrations]

Thu, 9 Apr 2026 16:01:50 GMT

Besedin, J.A., D.A. Besedin, L.S. Khudur, S.K. Biek, G. Aguilar Jr., P. Netherway, A. L. Juhasz, S. Horner, and A.S. Ball. Science of The Total Environment 1020:181602(2026)

Historic gold mining in Australia produced arsenic-contaminated waste, and Victoria has reported arsenic concentrations up to 47,100 mg/kg in impacted soil. Soil arsenic concentrations above 100 mg/kg in residential soil with garden access require site-specific management and remediation. A 6-month pilot was conducted to investigate P. labillardieri for plant growth and arsenic bioaccumulation under field conditions and assess soil amendment, 5% biosolids biochar (wet weight (w/w)) plus 5% compost (w/w), for optimization. Objectives included quantification of soil characteristics, soil and plant metal(loid) concentrations by acid digestion, arsenic bioaccumulation, and microbial analyses by quantitative polymerase chain reaction. P. labillardieri successfully grew and bioaccumulated arsenic under field conditions with and without the amendment (5% biochar plus 5% compost). The plant-only treatment significantly (p = 0.01) bioaccumulated more arsenic in the roots (?108 mg/kg) than plant plus amendment (?55 mg/kg); and had a significantly (p = 0.017) higher bioconcentration factor, demonstrating the plant's potential for phytostabilisation without assistance. A long-term field trial with additional analyses is recommended to validate P. labillardieri and the soil amendment for phytostabilisation of gold mine waste-impacted soil. https://www.sciencedirect.com/science/article/pii/S0048969726002639/pdfft?md5=f04a28e58c681dd5c56e305e1b70a8fc&pid=1-s2.0-S0048969726002639-main.pdf

FRACTIONATION OF CRITICAL METALS FROM AUTHENTIC ACID MINE DRAINAGE USING A MULTI-BED IMMOBILIZED AMINE SORBENT SETUP: A FIELD SITE STUDY [Demonstrations]

Thu, 9 Apr 2026 16:01:32 GMT

Wilfong, W.C., Q. Wang, B. Howard, P. Tinker, K. Johnson, W. Garber, F. Shi, and M.L. Gray.
Journal of Water Process Engineering 58:104788(2024)

A pilot employed a flow-through multi-fixed-bed immobilized amine/silica sorbent strategy to fractionate purified critical metals from authentic acid mine drainage (AMD). DOE's National Energy Technology Laboratory's patented Multi-functional Sorbent Technology sorbents were used to recover critical metals from AMD at the Pittsburgh Botanic Garden. By adjusting the AMD/sorbent ratio, >80% of pure adsorbed Mn (by adsorbed metal weight) and >90% pure adsorbed Al were recovered at lab-scale. Further optimizing the weight hourly space velocity (WHSV) enhanced the rate of adsorbed Al recovery by over 5x, justifying a field site test. After treating >100 L of AMD at the field site, the optimized polyamine/epoxysilane/aminosilane sorbent recovered ~0.7 wt% adsorbed Al at >90% purity. A tangible amount of purified aluminum hydroxide and aluminum sulfate solids was then recovered after eluting and precipitating the previously adsorbed metals.

PROJECT BACKGROUND, DEVELOPMENT AND DESIGN FOR THE LITTLE CONEMAUGH MINE DRAINAGE TREATMENT PLANT PROJECT, CAMBRIA COUNTY, PA [Cleanup News]

Thu, 9 Apr 2026 16:01:11 GMT

Cavazza, E. 27th Annual PA AMR Conference, 14-16 October, State College, PA, 41 minutes, 2025

Drainage from abandoned coal mining operations significantly impacted the Little Conemaugh River Watershed. The Pennsylvania Department of Environmental Protection, in partnership with several other federal, state, and local government entities and non-governmental organizations, began efforts in 2016 to restore the Little Conemaugh River from its headwaters to its confluence with the Stonycreek River in downtown Johnstown, a distance of ~15 stream miles. The effort is focused on the three most upstream major AMD discharges, including the Hughes Borehole, the Sonman Borehole Discharges, and the Miller Shaft Discharge. A restoration goal of biological recovery of the stream to support a recreational fishery was established. The water quality goals include maintaining the stream pH between 6.0 and 9.0, the alkalinity greater than acidity, the total iron <1.5 mg/L, the total aluminum <0.5 mg/L, and the total dissolved solids (TDS) <1,500 mg/L during normal stream flow. Property was purchased to obtain permanent right of way for a large-scale active mine drainage treatment plant (12,000 GPM maximum hydraulic capacity) and for a mine water conveyance and transfer pipeline. The design of the Little Conemaugh Mine Drainage Treatment Plant (LCMDTP) was completed in December 2024. Background information, including details about the abandoned mines, the major discharges (flow and chemistry), and the current design plan and schedule for the LCMDTP, is presented. https://www.youtube.com/watch?v=VYUN_2xS2I0

BLACKLICK CREEK - THE DEATH AND RESURRECTION OF A WATERSHED [Cleanup News]

Thu, 9 Apr 2026 16:00:53 GMT

Smoyer, J. and R. Farabaugh. 27th Annual PA AMR Conference, 14-16 October, State College, PA, 41 minutes, 2025

This presentation reviews the history of coal mining in Vintondale and Wehrum and explains how this history set the stage for the pollution and recovery of Blacklick Creek. The Bureau of Abandoned Mine Reclamation's $28 million acid mine drainage treatment plant, which began running in the spring of 2025, is highlighted along with initial post-treatment water quality data. https://www.youtube.com/watch?v=g1SI4gKEXP4

CENTRAL MINE REMEDIATION: SUCCESS STORY OF CLOSURE OF ANOTHER LEGACY MINE IN MANITOBA [Cleanup News]

Thu, 9 Apr 2026 15:54:55 GMT

Ahmeduzzaman, M., C. Graham, and D. Adedapo. Tailings and Mine Waste 2025 Conference, 2-5 November, Banff, AB, Canada, 16 pp, 2025

The abandoned Central Manitoba Mine (CMM) in Nopiming Provincial Park, Manitoba, posed significant environmental and public safety hazards due to acid-generating tailings, waste rock stockpiles, deteriorated infrastructure, and open mine shafts connected to an extensive underground network. This paper presents the design and implementation of a hybrid capping system engineered to mitigate acid-generating tailings, prevent contamination, and enhance site stability. The design considered a potentially liquefiable foundation, high groundwater conditions, material availability, long-term performance, and constructability challenges. The system incorporated Draintube technology, high-density polyethylene geomembrane liner, and nonwoven geotextile layers to ensure durability and minimize environmental impact. Remediation also included site regrading, tailings encapsulation, concrete capping of mine openings, and debris removal to restore the site. Construction was carefully planned and staged to minimize the risk of tailings liquefaction and prevent the release of tailings downstream. A rigorous quality control and assurance program was implemented to ensure that the remediation work met the design specifications and the vision of all stakeholders. Continuous monitoring and testing were conducted throughout the construction process to verify compliance and optimize material usage. The project was completed ahead of schedule and within budget, demonstrating the effectiveness of innovative engineering design in mine site rehabilitation. The paper highlights the key technical considerations, challenges, and lessons learned, contributing to the ongoing advancement of environmental stewardship and public safety in mine remediation. https://drive.google.com/file/d/1w-7RMt2IOE8SRjA-RF5yYJ9m2Um1mlKE/view

FROM REHABILITATION TO RESTORATION: A 12-YEAR CASE STUDY [Cleanup News]

Thu, 9 Apr 2026 15:54:33 GMT

Haagner, A. and F. van Wyk. Proceedings of the 18th International Conference on Mine Closure, 12 pp, 2025

The development of post?mining restoration efforts on a platinum mine has been tracked for the past 12 years, and findings have been used to guide the maintenance actions required to sustain ecosystem recovery trajectories. The extensive monitoring framework covers landform recreation, soil hydrology and physics, soil chemistry and microbial activity, vegetation dynamics, and recolonization of rehabilitating sites by birds, mammals, reptiles, and amphibians. The paper shows how the original rehabilitation?focused planning transformed into a restoration mindset. Shifts in ecosystem resilience following droughts, fires, and intensive grazing, as well as social expectations (the majority of the site is within the Marikana Thornveld vegetation type, recently uplisted to endangered status), required ongoing planning and management responses. The ecosystem responses to post?disturbance ecological development have shown improving trends across 12 years of monitoring, with stochastic deviations from trends observed for different taxa under varying prevailing conditions. The long?term nature of the monitoring program allowed for high?confidence trend analyses that inform restoration planning and maintenance activities. While restoration efforts were not perfectly executed, and external ecosystem stressors have hampered consistent ecosystem development, the case study shows the importance of undertaking rehabilitation and restoration activities within a clear framework that is outcome?oriented and data?driven. https://papers.acg.uwa.edu.au/d/2515_94_Haagner/94_Haagner.pdf

SOURCES SOUGHT NOTICE - FISCAL YEAR (FY) 2027 FLORIDA PANHANDLE OPTIMIZED REMEDIATION CONTRACT (ORC) AND MILITARY MUNITIONS RESPONSE PROGRAM (MMRP) (SRCSGT) [Market/Commercialization]

Thu, 9 Apr 2026 15:54:17 GMT

U.S. Army Corps of Engineers, South Atlantic Engineer Division, Mobile, AL
Contract Opportunities on SAM.gov W9127827RA002, 2026

This is a sources sought notice for marketing research purposes only under NAICS code 562910. The U.S. Army Corps of Engineers seeks responses from qualified firms interested in supporting the FY27 Florida Panhandle Group Optimized Remediation Contract (ORC) and Military Munitions Response Program at Eglin Air Force Base, Hurlburt Field, and Tyndall Air Force Base in Florida. The project involves comprehensive environmental remediation services across multiple sites, including investigation, design, construction, operation and maintenance, optimization, and achievement of site-specific performance objectives. The Contractor will support remediation at 59 IRP sites and five MMRP sites across Eglin AFB, Hurlburt Field, and Tyndall AFB, in accordance with applicable regulatory frameworks such as RCRA, CERCLA, and Florida Administrative Code requirements, with oversight primarily from the Florida Department of Environmental Protection and USEPA Region 4. Certain petroleum-contaminated sites will be addressed under state cleanup criteria, and any sites deferred from CERCLA will meet performance objectives with regulatory approval. The effort will be executed as a competitive, firm-fixed-price, definite-delivery contract using a best-value tradeoff approach, with an estimated value of $40 million and a 10-year period of performance consisting of a 5-year base and 5-year option period. The type of set-aside decision(s) to be issued will depend upon the capabilities of the responses to this synopsis. Responses are due by 3:00 PM CDT on April 22, 2026. https://sam.gov/workspace/contract/opp/4bd1855ad8424115afbb78c72739bd7b/view

MISSISSIPPI GROUP OPTIMIZED REMEDIATION CONTRACT AT COLUMBUS AIR FORCE BASE, MISSISSIPPI, KEESLER AIR FORCE BASE, MISSISSIPPI (SOL) [Market/Commercialization]

Thu, 9 Apr 2026 15:53:59 GMT

U.S. Department of the Air Force, Air Force Materiel Command, Installation and Mission Support Center, JBSA Lackland, TX
Contract Opportunities on SAM.gov FA890326R0001, 2026

This is an 8(A) set-aside under NAICS 562910. The U.S. Department of the Air Force requires a contractor to provide environmental remediation activities at Columbus Air Force Base (AFB) and Keesler AFB in Lowndes County in northeastern Mississippi under the Optimized Remediation Contract. The range of activities includes investigation, design, construction of remedial systems, operation and maintenance of established remedies, optimization at applicable sites, and achievement of site-specific objectives. The Contractor shall undertake environmental remediation activities to achieve performance objectives at 17 Installation Restoration Program sites. Offers are due by 2:00 PM CDT on April 16, 2026.
https://sam.gov/workspace/contract/opp/6678c2ec7d0f48429b4bb27b60edd130/view

REQUEST FOR PROPOSAL FOR ENVIRONMENTAL REMEDIATION SERVICES (ERS) SINGLE AWARD TASK ORDER CONTRACT (SATOC) FOR THE SHAW AIR FORCE BASE OPTIMIZED REMEDIATION CONTRACT (ORC) (SOL) [Market/Commercialization]

Thu, 9 Apr 2026 15:53:35 GMT

U.S. Army Corps of Engineers, South Atlantic Engineer Division, Savannah District, Savannah, GA
Contract Opportunities on SAM.gov W912HN26RA009, 2026

This is a total small business set-aside under NAICS code 562910. The U.S. Army Corps of Engineers, South Atlantic Engineer Division, requires a contractor to provide Environmental Remediation Services (ERS) under a $40 million Single-Award Task Order Contract (SATOC) for the Shaw Air Force Base Optimized Remediation Contract. The objective is to achieve site closure for unrestricted residential use in accordance with the installation's RCRA permit. Work includes remediation at 18 Installation Restoration Program (IRP) sites and operation and maintenance of two groundwater treatment plants, with varying performance objectives, including RA-O, IRA-O, LTM, and alternative objectives. The contract will be firm fixed-price with a seven-year ordering period and one six-month option. Offers are due by 2:00 PM EDT on April 24, 2026. https://sam.gov/workspace/contract/opp/22379d5625af434c8910fcdef026e444/view

A STATISTICAL SUMMARY AND VISUALIZATION TOOL FOR 30 YEARS OF BACKGROUND SOIL AND SEDIMENT METALS DATA FROM NORTH CAROLINA SUPERFUND SITES [General News]

Fri, 20 Mar 2026 15:43:40 GMT

Ogwu, M.C., F.M. Nilsen, W.F. Hunneke, L. Norris, R.J. Kelley, P.P. Goodwin, M.A. Nichols, A.R. Van Venrooy, and J.T. Bateson.
Integrated Environmental Assessment and Management 22(1):260-268(2026)

Remediating CERCLA sites is limited to cleanup to levels no lower than background concentrations. However, anthropogenically induced and naturally occurring metal concentrations in soil and sediments often complicate this cleanup process. A statewide dataset of background heavy metal data from Superfund site investigations was compiled to support informed decisions on heavy metal cleanup and the development of soil heavy metal-related policies in North Carolina. The dataset represents background concentrations at 326 Superfund sites found in North Carolina from 1985 to 2015. This 30-year dataset comprises site location data and analytical measurement results for 18 heavy metals in 624 soil and 228 sediment samples, obtained using standard methods. The data are presented in an interactive dashboard, offering summary statistics and graphical representations that can be customized to support specific decision-making needs. The data and dashboard: (1) inform and support cleanup decisions and policy development regarding soil heavy metals, and (2) increase public awareness of the levels of naturally occurring and anthropogenic background heavy metals in soil and sediments across the state. The publicly accessible and interactive dashboard offers a deeper understanding of background environmental conditions in relation to evolving anthropogenic contamination within a broader context.

ADVANCES IN REMEDIATION: PFAS PRECURSORS—DARK MATTER MENACE OR NEGLIGIBLE NOTHINGBURGER? [General News]

Fri, 20 Mar 2026 15:43:25 GMT

Divine, C., T.L. Torralba-Sanchez, T. Blount, T. Guillette, B. Miatke, and J. Lang.
Groundwater Monitoring & Remediation 46(1):10-20(2026)

PFAS precursors can act as a substantial long-term hidden source of regulated PFAAs, yet in many settings, strong sorption, limited mobility, analytical uncertainty, and slow transformation limit their practical impact on site management decisions. While dozens of terminal PFAAs can be measured, they represent only a fraction of the total PFAS mass potentially present. Many can act as precursors capable of converting into PFAAs. Whether hidden " dark matter" precursors are an important long-term driver of plume persistence, or mostly a chemically inert and immobile "nothingburger" locked up in soil pores, is an active debate. Scientific rationale and empirical laboratory and field observations for both perspectives are presented, followed by suggestions for practical considerations for investigation, data analysis, and visualization, conceptual site models, and site management strategies.

MAPPING RESEARCH ON MICROBIAL REMEDIATION OF METALS IN SOIL (2020-2025) [General News]

Fri, 20 Mar 2026 15:43:09 GMT

Usmonkulova, A., M. Pugliese, M. Julie, I. Khalilov, N. Kurbonova, N. Tillyaxodjayeva, R. Karimova, W. Liu, F. Khalilova, and O. Jabborova.
Microbiology Research 17(1):10(2026)

A systematic literature review using bibliometric analysis was conducted to examine the evolution and current trends of biological remediation studies. The bibliometric analysis was used for descriptive, intellectual, social, and conceptual network analyses, while systematic reviews were used to identify the application of biological remediation. A total of 4,835 papers were selected and extracted from Scopus between 2020 and 2025. The publication trends, most influential countries and articles, leading journals, collaboration networks, coupling networks, and application of biological remediation in various disciplines were described. This article highlights new research directions in current bioremediation trends: (1) understanding the interactions between petroleum hydrocarbons and heavy metals in composite pollution systems; (2) exploring microbial community succession during bioremediation; (3) utilizing biosurfactants to enhance contaminant solubilization and biodegradation; and (4) developing integrative, multi-mechanistic remediation approaches. This article is Open Access at https://www.mdpi.com/2036-7481/17/1/10.

THE HIDDEN COSTS OF PFAS REMEDIATION: ENERGY, WASTE, AND LONG-TERM VIABILITY [General News]

Fri, 20 Mar 2026 15:33:34 GMT

Laija, E., Bamer, J., and Molzahn, P. RemPlex Seminar, 2025

This seminar explores the environmental footprint of treating PFAS contamination. Presenters discuss the energy demands, waste generation, and broader environmental impacts of PFAS treatment technologies, offering insights into how these factors, alongside the regulatory context, should shape decision-making around remediation. Attendees gained insights into:

The energy demands and waste generation associated with current PFAS cleanup technologies.

Methodologies for calculating the environmental footprint of remediation strategies.

How treatment technology selection is influenced by both environmental impact and regulatory context.

Emerging perspectives on remedy sustainability and life cycle implications for PFAS remediation.

https://www.pnnl.gov/projects/remplex/seminars/hidden-costs-pfas-remediation?utm_source=chatgpt.com

Slides:https://www.pnnl.gov/sites/default/files/media/file/PDF%20-%20RemPlex-SURF_PFAS_Seminar_8-19-25.pdf

GROUNDWATER CONTAMINATION PLUME STABILITY REVIEW OF ASSESSMENT METHODS [General News]

Fri, 20 Mar 2026 15:33:13 GMT

Contaminated Sites Approved Professional Society (CSAP) Report CA0038290.6960-001-R-Rev1, 55 p, 2024

This review document provides practitioners with a summary of various plume stability assessment techniques, considerations for conducting a plume stability assessment, and examples of plume stability applications. The intended audience for this document is the CSAP Society and contaminated sites practitioners. https://csapsociety.bc.ca/wp-content/uploads/2024-12-03-Groundwater-Plume-Stability-Assessment-Methods-Final.pdf

Presentation on document: https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver_Calgary-2026-%E2%80%93-Joe-Ricker.pdf

MODELING PER- AND POLYFLUOROALKYL SUBSTANCE PRECURSOR TRANSFORMATION IN GROUNDWATER AT A WELL-CHARACTERIZED SITE [Research]

Fri, 20 Mar 2026 15:32:50 GMT

Stockwell, E.B., D.T. Adamson, J.D. Gamlin, P.R. Kulkarni, A. Singh, R.W. Falta, and C.J. Newell. Journal of Contaminant Hydrology 276:104766(2026)

A semi-analytical groundwater model that considers matrix diffusion was calibrated to field PFAS data at a site that contained PFAAs and their respective precursor compounds. The modeling effort considered PFOS, PFOA, PFHxS, and PFBS. Individual precursor compounds were grouped according to their ability to transform into one of four key PFAAs. Model calibration that varied source characteristics, fate and transport parameters, and precursor transformation indicated that precursor transformation could be a critical process for three of the four PFAAs: 40 years after the initial source release ~59%, 84%, and 87% of the PFOA, PFHxS, and PFBS plume maximum concentrations, respectively, originated from precursor transformation. In addition, precursor transformation led to PFOA, PFHxS, and PFBS plumes that were up to 17% longer than if precursor transformation did not occur. In contrast, PFOS was not substantially affected by precursor transformation due to high PFOS concentrations in the source zone compared to its precursors. Additional modeling of complete PFAS source removal indicated that the effects of matrix diffusion, coupled with no natural degradation of certain PFAAs, may result in PFAS plumes at this site that persist and are sustained by precursor transformation. https://www.sciencedirect.com/science/article/pii/S0169772225002712/pdfft?md5=5c4d7ae57b8e251e75e9386e5528d7f2&pid=1-s2.0-S0169772225002712-main.pdf

EVALUATION OF 1,4-DIOXANE NATURAL ATTENUATION AFTER IN SITU PROPANE BIOSPARGING: BENCH-SCALE MICROCOSM TESTS AND FIELD METADATA ANALYSIS [Research]

Fri, 20 Mar 2026 15:32:24 GMT

Antunes, J.M.D., D.K.D. Gaudel, C.H. Bell, Z. Wahl, M. Schnobrich, and M. Li.
Remediation 36(2):e70060(2026)

Bench-scale microcosms were conducted with groundwater collected from seven monitoring wells located along the 1,4-dioxane plumes at two sites where propane biosparging (and bioaugmentation) were previously employed. Over four weeks of incubation, significant 1,4-dioxane removal was observed in microcosms prepared with groundwater samples from four locations within the proximity of historical treatment zones. First-order attenuation rates ranged from 0.02 to 1.11/day, corresponding to half-lives between 0.6 and 32.0 days. Concurrently, a meta study was conducted by compiling groundwater data from >?900 monitoring wells across the U.S. Estimated bulk 1,4-dioxane degradation/attenuation half-lives ranged from 109 to 6,405 days (R²?>?0.5). The majority (96%) of the estimated half-lives were < 3,000 days, with the shorter half-lives (i.e., faster rates) generally observed at higher 1,4-dioxane concentrations (i.e., >?20?µg/L). Propane biosparging exhibited significantly shorter half-lives (i.e., a median half-life of 445 days) than MNA and P&T technologies. In addition, 1,4-dioxane half-lives after the start of propane biosparging treatment were an order-of-magnitude shorter than those before treatment, which may also explain the additional orders-of-magnitude decreases in half-lives in MNA-mimicking microcosms. Together, these findings indicate that propane biosparging not only accelerates immediate 1,4 dioxane removal but also "primes" microbial communities for enhanced long term attenuation.

NOVEL REMEDIATION STRATEGIES FOR CR(VI)-CONTAMINATED GROUNDWATER AT LOW TEMPERATURE: STUDY ON THE EFFECTS OF COMBINING ASCORBIC ACID REDUCTION WITH BIOSTIMULATION [Research]

Fri, 20 Mar 2026 15:32:10 GMT

Yang, X., L. Hou, X. Yuan, H. Guo, and F. Ma.
Journal of Environmental Management 403:129156(2026)

Ascorbic acid (AA) combined with molasses was used to remediate Cr(VI) in experiments at 8°C to accelerate the initiation of bioreduction and broaden the applicable range of biostimulation. Results demonstrated that the Cr(VI) reduction efficiency was significantly inhibited by both dissolved oxygen and aquifer media when treated with AA. However, excess addition of AA (n[AA]): n(Cr[VI]) = 2:1) could eliminate the inhibitory effect of non-target reactions. Compared to the molasses-only control, the average removal rates of Cr(VI) in the systems with the additional 38, 86, and 170 mg/L of AA were increased by 0.87, 1.07, and 2.24 mg/(L·d). AA rapidly reduced Cr(VI) within 6 h, and the subsequent bioavailable molasses had the greatest Cr(VI) removal rate [2.47 mg/(L·d)] when the Cr(VI) concentration was decreased to near 40 mg/L. Higher AA additions under combined treatment increased the relative abundance of Bacillus from 26% to 46% and 50%, respectively. In addition, the expression of genes related to Cr(VI) detoxification was upregulated by AA combined with molasses remediation. The expression of ChrA in AA-molasses-amended systems was 1.52 times (38 mg/L AA) and 1.68 times (86 mg/L AA) that of molasses-amended system, respectively. The relative expression of SOD1 in AA-molasses-amended groups was 1.56 (38 mg/L AA) and 1.84 times (86 mg/L AA) that of the molasses-amended system.

TOWARD CLOSED-LOOP REMEDIATION: A DYNAMIC OPTIMIZATION APPROACH FOR HYDRAULIC CONDUCTIVITY ESTIMATION AND PUMP-AND-TREAT DESIGN [Research]

Fri, 20 Mar 2026 15:29:01 GMT

Wei, J., S. Jiang, Q. Liu, X. Zhang, N. Zheng, and J. Xing.
Journal of Contaminant Hydrology 277:104852(2026)

A study proposed a dynamic iterative optimization framework that integrates parameter inversion with remediation plan design into a closed-loop system of simulation-observation-update-optimization. The framework iteratively updates the K-field using pilot point parameterization and simulation-optimization techniques while dynamically adjusting the remediation strategy based on real-time monitoring data. Numerical experiments conducted on a virtual contaminated site demonstrated that the proposed framework significantly improves the accuracy of K-field characterization, as evidenced by decreasing logarithmic root mean square error and increasing spatial correlation coefficient over iterations. When compared with a conventional static remediation plan that is designed once and executed without updates, the dynamic framework achieves a substantially higher contaminant removal rate while simultaneously reducing the total pumping volume. Results highlight the framework's potential to enhance remediation effectiveness and reduce operational costs in heterogeneous aquifers, offering a practical and adaptive solution for complex contaminated site management.

PFAS FATE USING LYSIMETERS DURING DEGRADED SOIL RECLAMATION USING BIOSOLIDS [Research]

Fri, 20 Mar 2026 15:28:45 GMT

Peter, L., M. Modiri-Gharehveran, O. Alvarez-Campos, G.K. Evanylo, and L.S. Lee.
Journal of Environmental Quality 54(1):41-53(2025)

A study investigated PFAS persistence and leaching from biosolids applied to an artificially constructed site to mimic degraded soils. Biosolids and biosolids blended with mulch were applied at different rates to attain either one and five times the agronomic N rate for vegetable crops, and a control treatment with synthetic urea and triple superphosphate fertilizer. Leachates were collected for 2 years from 15-cm depth zero-tension drainage lysimeters. Soils were analyzed post-biosolids application. PFAS were quantified using isotope-dilution, solid-phase extraction, and liquid chromatography tandem mass spectrometry. Leachate profiles exemplified an initial high total PFAS concentration, followed by a sharp decline and subsequent small fluctuations attributed to pre-existing soil conditions and rainfall patterns. Quantifiable PFAS in leachate were proportional to biosolids application rates. Short-chain PFAAs (CF₂ < 6) were dominant in leachate, while the percentage of longer-chain homologues was higher in soils. A 43% biosolids blend with mulch resulted in 21% lower PFAS leachate concentrations, even with the blend application rate being 1.5 times higher than biosolids due to the blend's lower N-content. The blending effect was more pronounced for long-chain perfluoroalkyl sulfonic acids that have a greater retention by soils and the air-water interface. https://acsess.onlinelibrary.wiley.com/doi/epdf/10.1002/jeq2.20576

BENCH MORE, SWEAT LESS: CASE STUDIES USING BENCH-SCALE TESTING TO EXPOSE HIDDEN ISSUES, REFINE REMEDIAL OPTIONS, AND IMPROVE BUDGETING. [Research]

Fri, 20 Mar 2026 15:28:21 GMT

Reichheld, S. | SMART Remediation, 20 January, Vancouver, Canada, 16 slides, 2026

Practical case studies are highlighted where targeted bench-scale testing using site soil and groundwater samples strengthened remedial decisions and improved field outcomes. The case studies show how bench results clarified viable treatment options, narrowed design ranges, and supported more defensible remedial timelines and cost estimates.
https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver-2026-%E2%80%93-Steve-Reichheld.pdf

RESEARCH BRIEF 370: IMPROVING CHEMICAL CLEANUP OF CONTAMINATED GROUNDWATER [Research]

Fri, 20 Mar 2026 15:28:06 GMT

National Institute of Environmental Health Sciences, Superfund Research Program (SRP), February 2026

Researchers from the University of California, Berkeley Superfund Research Program (SRP) Center uncovered how underground conditions influence the success of chemical oxidation-based groundwater cleanup. By considering how contaminants interact with underground particles, the study provides guidance that could help tailor cleanup approaches to site-specific conditions, improving remediation outcomes. https://tools.niehs.nih.gov/srp/researchbriefs/view.cfm?Brief_ID=370

FIELD APPLICATION OF BIOELECTROCHEMICAL REDUCTION TECHNOLOGY FOR TREATING HEXAVALENT CHROMIUM IN GROUNDWATER [Demonstrations]

Fri, 20 Mar 2026 15:27:47 GMT

Li, Y., D. Kong, K. Jin, X. Dong, Q. Zhang, and L. Chen.
Journal of Contaminant Hydrology 276:104744(2026)

A commercialized bioelectrochemical reduction (BECR) technology (E-Redox®-R) was applied at a Cr(VI)-contaminated site in Henan Province, China, to remediate chromium-contaminated groundwater in a pilot study. The BECR pilot system consisted of four units, comprising 12 electrodes installed across a 38.5-m transect. For each unit, one anode well and two cathode wells were arranged in an isosceles triangle configuration, with an inter-electrode spacing of 5.5 m. Within 10 months of system operation, groundwater Cr(VI) concentrations in the cathode wells, ranging from 0.3 mg/L to 46.5 mg/L, decreased by 24% to 99% despite potential masking effects by the desorption of chromium mass from the soil matrix into the aqueous phase. Within the treatment zone, Cr(VI) concentrations in the two upgradient monitoring wells located near the anode electrodes decreased by 21% and 42%, respectively, while concentrations in the three downgradient monitoring-compliance wells near the cathode electrodes decreased by 65% to 96%. Results indicate that the BECR technology can effectively reduce Cr(VI) in the subsurface and holds promise as a sustainable in situ technology for remediating chromium and other contaminants in impacted groundwater.

PILOT-SCALE PERFORMANCE OF A UV-REGENERABLE IRON-BASED ACTIVATED CARBON SYSTEM FOR PHARMACEUTICAL AND PFAS REMOVAL [Demonstrations]

Fri, 20 Mar 2026 15:27:26 GMT

Beak, S., E. Kim, T. Jung, J. Lee, and J. Bae.
Journal of Water Process Engineering 82:109468(2026)

A 200 m³/day pilot was constructed and continuously operated at a municipal wastewater treatment plant (WWTP) in Daegu, South Korea, that coupled iron-impregnated powdered activated carbon (Fe-PAC) with ultraviolet (UV)/ H_?O_? photo-regeneration to restore adsorption in situ. Bench tests verified Fe-site-enabled photo-Fenton reactions. Robustness was pilot-assessed under actual, variable influent fluctuations. Without regeneration, short-chain PFAS (PFHxA and PFHpA) showed limited, unstable removal; long-chain PFNA and PFOA decreased over time owing to site saturation. Most pharmaceuticals (diclofenac and florfenicol) sustained ≥90% removal; hydrophilic caffeine decreased transiently but recovered after regeneration, whereas atenolol exhibited lower long-term stability. With periodic UV/H_?O_? treatment, PFAS removal exceeded 95% after three months; aggregate removal reached 97.7 and 99.1% at three and five months, respectively, without deterioration of water-quality indicators. Fe-PAC acted as a dual adsorbent-catalyst: pores captured contaminants, and Fe sites generated radicals that decomposed surface residues and reopened adsorption sites, providing pilot-scale evidence that the UV-regenerable Fe-PAC hybrid can overcome adsorption limitations and deliver robust control of persistent micropollutants. Optimizing the regeneration frequency and intensity and performing techno-economic evaluations to support full-scale deployment are recommended. https://www.sciencedirect.com/science/article/pii/S2214714426000267/pdfft?md5=4af1b93cb0f7b21df11014da5b0f8b5a&pid=1-s2.0-S2214714426000267-main.pdf

SIMULATOR -TRAINED AI FOR CREATING SUBSURFACE DIGITAL TWINS USING TIME -LAPSE ELECTRICAL RESISTIVITY TOMOGRAPHY DATA [Demonstrations]

Fri, 20 Mar 2026 15:27:14 GMT

Johnson, T.C. | Pacific Northwest National Laboratory RemPlex seminar, 4-6 November, Richland, WA, 21 minutes, 2025

Presenters describe how the hydrogeologic information content implicit in time-lapse electrical resistivity tomography (ERT) data can be extracted and assessed using generative artificial intelligence (AI). The trained AI model generates ensembles of subsurface models that honor field observations, thereby providing a mechanism for assessing uncertainty. The approach was demonstrated at the Hanford 100K-Area in situ soil flushing test, where ERT was used to monitor vadose zone hexavalent chromium remediation through in situ soil flushing.

See times 1 minute-23 minute: https://www.pnnl.gov/projects/remplex/2025-summit/technical-sessions/artificial-intelligence

Slides:https://www.pnnl.gov/sites/default/files/media/file/2025%20RemPlex%20-%20Technical%20Session%208%20-%20Tim%20C.%20Johnson%20-%20Simulator-Trained%20AI.pdf

PFAS VADOSE ZONE MASS DISCHARGE AT AN AFFF-IMPACTED SITE: 1. VALIDATION BASED ON A MULTIPLE LINES-OF-EVIDENCE APPROACH [Demonstrations]

Fri, 20 Mar 2026 15:25:51 GMT

Carey, G.R., D.T. Adamson, R.K. Krebs, M. Rebeiro-Tunstall, K.G. Mumford, B. Guo, G.T. Carey, K. Rooney, and S. Moga. | Remediation 36(2):e70058(2026)

Multiple lines of evidence were evaluated to determine if porewater samples collected during a data gap investigation in the former fire training area (FFTA) at Ellsworth Air Force Base were reproducible and representative. Lines of evidence included supplemental geologic and hydrogeologic data, which showed the presence of a semi-continuous silt/clay layer directly above the water table throughout much of the FFTA, and gravimetric moisture content results that demonstrated vertical water flow at a depth of 15?ft is substantially limited due to semi-arid climatic conditions. Radial diagrams visually demonstrated that there was negligible variability in porewater concentrations caused by varying sample yields in the deep zone. Additional lysimeters installed in the FFTA during the investigation did not result in a significant difference in the estimated vertical mass discharge, which showed that the number of lysimeter sampling points in this area is sufficient. Strong attenuation in PFAS soil concentrations with depth validates the order(s) of magnitude reduction between shallow and deep porewater concentrations observed near the former burn pit. Vadose zone PFAS mass discharge was shown to be 4%-19% of groundwater mass discharge below the water table for regulated constituents. Recommendations for field data collection and estimation of PFAS mass discharge in the vadose zone are presented. https://onlinelibrary.wiley.com/doi/epdf/10.1002/rem.70058

GOING WITH THE FLOW (AND A LITTLE REAGENT): AUGMENTING NATURAL ATTENUATION TO TACKLE A CVOC PLUME [Cleanup News]

Fri, 20 Mar 2026 15:25:33 GMT

Hachborn, E. and B. Loney. | SMART Remediation, 20 January, Vancouver, Canada, 12 slides, 2026

The challenges and outcomes of a complex, multi-year in situ biochemical remediation program designed to address a cVOC groundwater plume at a site in Eastern Ontario are described. The plume originated from a former landfill and had been managed by a P&T system. Following a remedial options analysis and a successful pilot test, the in situ approach was selected as a more targeted method for cVOC mass reduction in the upgradient source area, in addition to phytoremediation downgradient of the plume. A primary challenge was adapting the program to the site's physical constraints and geological conditions. The complex terrain, combined with a necessary 15-meter buffer from an adjacent pond, required a dynamic injection design with variable point spacing and treatment depths to effectively target the main cVOC mass, which was concentrated 1.5 to 2.5 meters above the clay layer. The initial full-scale injection was conducted in early 2020, followed by a second event in late 2023 to maintain performance. The second program was hampered by weather. Low temperatures caused operational delays, affecting equipment like pumps and drill batteries. Site topography and access concerns necessitated the removal of several planned injection points from the program, requiring the redistribution of the remedial reagent to adjacent locations to maintain the target dosage. Despite these challenges, the program achieved its mass reduction objectives. Post-injection monitoring confirmed that the biochemical treatment stimulated the desired degradation of the parent cVOCs, successfully managing the plume so that no further injections are required at this time. It is planned to transition the site to a combined management strategy of monitored natural attenuation along with a recently implemented phytoremediation program to address the residual plume. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Ottawa-2026-%E2%80%93-Hachborn_Loney.pdf

DESIGN CONSIDERATIONS AND IMPLEMENTATION TECHNIQUES FOR IN SITU PFAS SEQUESTRATION USING MODIFIED CLAY [Cleanup News]

Fri, 20 Mar 2026 15:25:14 GMT

Mazzarese, M. | SMART Remediation, 20 January, Vancouver, Canada, 11 slides, 2026

Recent pilot programs have demonstrated that FluoroSorb®, an organically modified bentonite clay (MC), can be injected into overburden to effectively sequester PFAS, offering higher sorption capacity and stability within the subsurface. Independent testing showed that MC exhibited strong sorption kinetics and capacity across a wide PFAS concentration range, with compatibility alongside other remedial amendments. Bench-scale evaluations compared performance against ion exchange resin, granular activated carbon, and biochar, and also assessed competitive sorption in the presence of chlorinated VOCs and petroleum hydrocarbons. Relevant kinetics and co-contaminant performance data are presented. Field deployments in the U.S. and Canada verified injectability and distribution of MC for source-area treatment and PFAS plume interception using direct-push injection. Multiple slurry densities were evaluated to match amendment mass to PFAS loading, including co-injection with calcium polysulfide for simultaneous PFAS and hexavalent chromium treatment. A Canadian PRB installation was monitored for more than a year under continued upgradient PFAS loading, with groundwater results and dye-assisted soil coring confirming amendment distribution, sequestration performance, and durability in situ. https://smartremediation.com/wp-content/uploads/2026/03/SMART-Vancouver_Calgary_Toronto_Ottawa-2026-%E2%80%93-Mike-Mazzarese.pdf

OPTIMIZATION TOOLS AND STRATEGIES IMPLEMENTED AT SITES WITH LONG-TERM REMEDIATION SYSTEMS [Cleanup News]

Fri, 20 Mar 2026 15:24:48 GMT

Perlmutter, M. NAVFAC Remediation Innovative Technology Seminar, 116 slides, 2025

This presentation highlights multiple Navy case studies that demonstrate how structured optimization reviews can significantly improve the performance, sustainability, and cost efficiency of long-term remediation systems. Across sites with decades-old remedies, the case studies show that periodic technical evaluation often identifies opportunities to reduce system footprint, modify operating parameters, or transition to alternative remedies while maintaining protectiveness. In several groundwater P&T examples, optimization reviews determined that contaminant mass removal rates had asymptotically declined after years of operation. Through data trend analysis, capture zone evaluation, and influent concentration review, flow rates were reduced, extraction wells were consolidated, and treatment trains were simplified without compromising hydraulic containment. The adjustments reduced energy demand and annual O&M costs while maintaining compliance with cleanup objectives. In some cases, targeted pulsed operation or seasonal pumping strategies were implemented to address rebound concerns more efficiently. Additional case studies involving SVE systems demonstrated diminishing vapor concentrations over time, indicating that systems had reached mass-transfer limitations. Optimization efforts included shutting down low-yield wells, modifying vacuum distribution, and conducting rebound testing to confirm whether active extraction could be terminated. Where appropriate, systems were transitioned to monitored natural attenuation, supported by updated conceptual site models and long-term monitoring plans. The case studies demonstrate that optimization is not a one-time event but an ongoing adaptive management process. By applying data-driven evaluations, refining system operations, and aligning remedies with current site conditions, measurable reductions in operating costs, improved system efficiency, and accelerated progress toward remedial endpoints without sacrificing protectiveness were achieved. https://exwc.navfac.navy.mil/Portals/88/Documents/EXWC/Restoration/er_pdfs/rits/2025/RITS%202025_Optimization_Final.pdf?ver=e6e3gUtUfa83p1xeQTDZ_A%3d%3d

EPA WERRC RFP (COMBINE) [Market/Commercialization]

Fri, 20 Mar 2026 15:19:26 GMT

U.S. Environmental Protection Agency, Region 9 Contracting Office, San Francisco, CA
Contract Opportunities on SAM.go 68HE0926R0002, 2026

This is a full and open competition under NAICS code 541620. EPA Region 9 seeks a contractor to support its Water Emergency Response Resources Contract (WERRC). The purpose of the WERRC is to provide services to EPA and other officials supporting the implementation of EPA's responsibilities under the Clean Water Act and Safe Drinking Water Act. Response activities will support EPA's obligations under the SDWA, CWA, the Stafford Act, as well as any future laws or regulations that establish or expand EPA's response obligations. Work will include Project Planning; General Water Sector Disaster Mitigation; Drinking Water System Response Activities; Wastewater System Response Activities; Analytical Services; Demolition, Restoration, and Soil Stabilization; Provision of Support Facilities to support Water Response/Recovery; Limited Marine/Water Operations; Training; and Logistical Services. The contractor shall support EPA in fulfilling these responsibilities within the region(s) assigned via contract, as well as outside the region on a backup regional response, cross-regional response, and national response. The awarded contract will include a one-year Base Period with four one-Year Option Periods. Questions are due by 5:00 PM on April 1, 2026. Proposals are due by 8:00 PM EDT on April 30, 2026.
https://sam.gov/workspace/contract/opp/92bbc8994cc9430e8d52f69c18c97d6f/view

EV35, NEWPORT, SITE 17, LTM, NORTH RAOMAC (SOL) [Market/Commercialization]

Fri, 20 Mar 2026 15:15:39 GMT

U.S. Department of the Navy, Naval Facilities Engineering Systems Command, Mid-Atlantic Command, Norfolk, VA
Contract Opportunities on SAM.go N4008526R0113, 2026

This is a full and open competition under NAICS code 562910. The Naval Facilities Engineering Systems Command, Mid-Atlantic Command, requires a contractor to perform long-term monitoring and monitored natural attenuation of groundwater at Site 17-NAVSTA Newport in Newport, Rhode Island. The LTM groundwater monitoring well network includes 21 monitoring wells; all wells are sampled biannually. Groundwater monitoring wells selected for sampling are intended to provide sufficient geographic coverage for evaluating MNA parameters and confirming COC concentrations in groundwater. All samples are analyzed for the following: select VOCs - Benzene, PCE, 1,2-DCE, TCE, VC; select metals- arsenic, cadmium, lead, and manganese; PAHs, plus pentachlorophenol PCBs; anions (chloride, N-nitrate, sulfate); and alkalinity. The duration of work under this Contract Task Order shall not exceed 12 months from the award date for the base option and 60 months from award, including option years. Offers are due by 2:00 PM EDT on April 7, 2026. https://sam.gov/workspace/contract/opp/f55fc89f54de47ea9f8e2438c9711e5c/view

SYNOPSIS OF SOLICITATION; FA890326R0019; OPTIMIZED REMEDIATION CONTRACT AT FAIRCHILD AIR FORCE BASE, WASHINGTON (PRESOL) [Market/Commercialization]

Fri, 20 Mar 2026 15:15:21 GMT

U.S. Department of the Air Force, Air Force Materiel Command, AF Installation and Missions Support Center, JBSA Lackland, TX
Contract Opportunities on SAM.go FA890326R0019, 2026

When this solicitation is released, it will be competed as an 8(a) set-aside under NAICS code 562910. The U.S. Department of the Air Force plans to issue a solicitation for environmental remediation activities under an Optimized Remediation Contract at Fairchild Air Force Base. The ORC initiative intends to advance site cleanup during the Period of Performance in the most efficient and cost-effective manner, as supported by a cost-benefit analysis and exit strategy that achieves the greatest reduction in life-cycle cost. The Air Force is interested in a substantial reduction of long-term environmental liabilities and total LCC. These sites have complex attributes that have, to date, inhibited progress toward the achievement of RC. Work will include plan development; Preliminary Assessment/Site Inspection; Remedial Investigation or Remedial Investigation/Feasibility Study, including supplemental investigations; preparation of Decision Documents; and Remedial Action-Operation or Long-Term Management. There is no solicitation at this time. https://sam.gov/workspace/contract/opp/8e17e583381f4a94bd2019faff448f42/view

CERCLA REMOVAL ACTION AT MOJAVE NP (PRESOL) [Market/Commercialization]

Fri, 20 Mar 2026 15:14:49 GMT

U.S. Department of the Interior, National Park Service, Washington Contracting Office, Lakewood, CO
Contract Opportunities on SAM.gov 140P2126Q0049, 2026

When this solicitation is released on or about March 27, 2026, it will be competed as an indian small business economic enterprise (ISBEE) set-aside under NAICS code 562910. The National Park Service plans to issue a solicitation for a Non-Time Critical Removal Action (NTCRA) under CERCLA at the 5-acre Hidden Hill Mine contaminated site within Mojave National Preserve in Southern California. The work includes removing ~69 yd³ of commingled tailings and potentially affected underlying material, based on an assumed thickness of ~1 ft across an area of ~1,850 ft². To account for additional underlying material and soils that may become commingled during excavation activities, a conservative estimate of ~100 yd³ of material will be removed during this Removal Action (RA). Using a conversion factor of 1.5 tons/ yd³, NPS estimates that ~150 tons of material will be excavated, transported, and disposed of as part of the RA. The work also includes preparation of post-award plans, characterizing the material, transporting it to appropriate disposal facility/ies, collecting and analyzing confirmation samples, and preparing a Response Action Completion Report. The estimated removal quantities are based on previous site investigations. The firm-fixed-price contract will use a combination of lump-sum and unit-priced items, subject to the variation in quantity clause in conjunction with an established ceiling and notification requirements. A payment bond (100%), performance bond (100%), and liability insurance will be required prior to contract performance. A group site visit is scheduled at 10:00 AM on April 9, 2026. Pertinent details will be provided in Section L of the solicitation when it is posted. Attendance at the site visit is strongly encouraged. Requests for individual site visits will not be honored. There is no solicitation at this time. https://sam.gov/workspace/contract/opp/423d2b5dab3f40f6b4ce36df85e5bdd0/view

ALTEMIS: NEXT-GENERATION IN SITU REAL-TIME GROUNDWATER MONITORING STRATEGIES [General News]

Fri, 6 Mar 2026 15:08:03 GMT

Wainwright, H. | Pacific Northwest National Laboratory RemPlex seminar, 4-6 November, Richland, WA, 21 minutes, 2025

The Advanced Long-Term Monitoring Systems (ALTEMIS) project is developing an innovative paradigm of long-term monitoring based on state-of-the-art technologies, such as in situ groundwater sensors, geophysics, drone/satellite-based remote sensing, reactive transport modeling, and AI, that will improve effectiveness and robustness, while reducing the overall cost. As a part of this project, an in situ real-time groundwater long-term monitoring framework was developed based on various sensors and data analytics methods. Rather than relying on one single metric, this approach provides multiple lines of evidence to ensure the system stability: (1) groundwater table and its gradient that governs the migration speed and direction of the contaminant plume, and (2) in situ measurable geochemical parameters for detecting changes in contaminant mobility. In addition, machine learning algorithms were developed to improve the spatiotemporal interpolation of groundwater tables and contaminant concentrations by exploiting proxy variables such as in situ sensors and geospatial layers, and detect anomalies by computing the difference between near-future forecasting and measurements. To accommodate noisy and drifting sensor data streams, algorithms were also developed for automated outlier removal and drift correction. The framework was demonstrated based on the plot-scale installation at the Savannah River Site F-Area.

See times 1:01-1:20: https://www.pnnl.gov/projects/remplex/2025-summit/technical-sessions/artificial-intelligence

Slides: https://www.pnnl.gov/sites/default/files/media/file/2025%20RemPlex%20-%20Technical%20Session%208%20-%20Haruko%20Wainwright%20-%20ALTEMIS.pdf

CURRENT KNOWLEDGE ABOUT PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS) IN THE ATMOSPHERE: FATE, ANALYTICAL METHODS AND RESEARCH PRIORITIES [General News]

Fri, 6 Mar 2026 15:07:32 GMT

Vieira, H.G., M.C. Canela, R.C. Urban, and B.S. Cabrero. | Chemosphere 389:144703(2025)

This article comprehensively overviews the current knowledge on PFAS, including a compilation of information on emission sources- primary sources and secondary sources; proposed classifications of their volatility based on vapor pressure by EPA and the European Chemicals Agency; atmospheric processes that govern gas-particle partitioning, long-range transport, and deposition; an assessment of current and emerging sampling and analytical techniques, including OTM 45/50 methods; and the identification of priority knowledge gaps. Among the main existing gaps, the validation of improved monitoring strategies and inhalation toxicity studies for neutral precursors could significantly contribute to a robust risk assessment and support regulatory efforts within the evolving global agenda for the phase-out of PFAS.

PFAS DESTRUCTION TECHNOLOGY DEMONSTRATIONS [General News]

Fri, 6 Mar 2026 15:07:08 GMT

Pinkard, B. and J. Follin | SERDP & ESTCP Webinar Series, January 2026

This webinar highlighted two PFAS destruction technologies, hydrothermal alkaline treatment (HALT) and supercritical water oxidation (SCWO). Hydrothermal alkaline treatment (HALT) leverages high pH conditions to destroy PFAS in liquid feedstocks. The project demonstrated HALT for the centralized disposal of several PFAS-rich liquid wastes produced during DoD site remediation efforts. PFAS destruction performance was measured and assessed for a range of operating conditions, leveraging many different analytical techniques to track the fate of fluorine and the extent of PFAS destruction. A legacy AFFF blend was processed onsite with HALT. This presentation describes the fundamentals of HALT, shares insights from the demonstration, and discusses best practices for integration within an effective treatment train for facilitating complete PFAS capture and destruction. SCWO is an innovative technology that has been previously demonstrated for the destruction of energetics and other organic wastes. The presentation focuses on recent tests that have been performed using this technology for PFAS destruction at a Clean Earth facility in Charlotte, NC, and at General Atomics' test facility in San Diego, CA. At the Charlotte facility, a mobile system was used to process and destroy three PFAS-laden waste streams and an AFFF concentrate. In San Diego, spent granulated activated carbon and ion-exchange resin beads were tested using a commercial SCWO system. The presentation summarizes the procedures, PFAS test results, and stack gas testing.

Video: https://www.youtube.com/watch?v=tjeXJxzaXqU&embeds_referring_euri=https%3A%2F%2Fserdp-estcp.mil%2F&source_ve_path=OTY3MTQ

Slides: https://sepub-prod-0001-124733793621-us-gov-west-1.s3.us-gov-west-1.amazonaws.com/s3fs-public/2026-01/SERDP%20ESTCP%20Webinar%20%23224%20%28ER%2001272026%29%20-%20Combined%20Slides%20V5%20%20-%20%20Read-Only.pdf?VersionId=6PhPI.JJNTiprNtXg520hgPu5Gmqyeho

IN SITU VERIFICATION AND QUANTIFICATION OF NATURALLY OCCURRINGDECHLORINATION RATES IN CLAYS: DEMONSTRATING PROCESSES THAT MITIGATE BACK-DIFFUSION AND PLUME PERSISTENCE FINAL REPORT [General News]

Fri, 6 Mar 2026 15:06:50 GMT

Schaefer, C., Z. Nguyen, D, Tran, C. Werth, T. Blount, S. Dai, and G. Kumar. ESTCP Project ER20-5031, 87 pp, 2025

This work aimed to demonstrate and validate an innovative approach for assessing and quantifying naturally occurring abiotic and biotic dechlorination reactions in low-permeability clays. Such an approach would guide RPMs and regulators in assessing naturally occurring abiotic dechlorination at DoD sites. The project employed multiple methods and techniques that have been demonstrated in previous laboratory and field projects to attain insight into a cost-effective and easily implementable in situ methodology that can be used to assess the extent to which naturally occurring abiotic and biotic dechlorination processes are occurring within clays (via a first-order rate constant). This in situ approach was utilized at eight sites. Using 1% (v/v) HCl extractions and X-ray diffraction for mineral composition provided information to estimate TCE abiotic reductive dechlorination in clays. However, the model could not be independently used to verify the lab-derived rate constants. For reductive abiotic dechlorination under anoxic conditions, results suggest that 1% HCl extraction coupled with XRD data can be used as a screening-level tool to verify and estimate reductive dechlorination rate constants.

Final Report: https://sepub-prod-0001-124733793621-us-gov-west-1.s3.us-gov-west-1.amazonaws.com/s3fs-public/2025-12/ER20-5031%20Final%20Report.pdf?VersionId=995rxTGNSMLWh8d4kNeKem7qXzRLolwE

Guidance: https://sepub-prod-0001-124733793621-us-gov-west-1.s3.us-gov-west-1.amazonaws.com/s3fs-public/2025-11/ER20-5031%20Guidance%20Document.pdf?VersionId=1s90wlFyECN0Z8FnYt3yLD9NlJjeBlKv

QUANTITATIVE SUSTAINABILITY ASSESSMENT OF IN SITU THERMALLY ENHANCED BIOREMEDIATION FOR CARBON EFFICIENT GROUNDWATER REMEDIATION [Research]

Fri, 6 Mar 2026 15:06:30 GMT

Yang, Z., Q. Wang, C. Wei, Z. Zhang, Z. Tang, Y. Li, G. Luo, F. Coulon, L. Fan, and X. Song.
Sustainable Production and Consumption 63:19-33(2025)

In situ thermally enhanced bioremediation (ISTEB) is a promising approach for remediating contaminated soil and groundwater. However, comprehensive quantitative sustainability assessments of its sustainability are limited, especially for field-scale applications using hot water injection (TEB-HW) or thermal conductive heating (TEB-TCH). A study addressed the gap by developing a quantitative sustainability framework integrating life cycle assessment with best management practices (BMPs), comprising 108 indicators derived from an extensive literature review and policy analysis. Using full-scale operational data from ISTEB implementations, the environmental, economic, and social performance of TEB-HW and TEB-TCH were quantified relative to conventional thermal treatment (TCH). Compared with TCH only, TEB-HW and TEB-TCH reduced carbon emissions by 78% and 31%, and achieved cost savings of 72% and 38%, while also improving community engagement and satisfaction. Normalized multi-criteria sustainability scores indicate overall performance gains of 31% and 13% compared to TCH only. Further optimization of BMPs, such as electric vehicle transport, green injectates, and renewable energy integration, could enhance ISTEB sustainability by up to 45%.

ADVANCED CARBON NANOMATERIAL-BASED ELECTROCHEMICAL PLATFORMS FOR REAL-TIME DETECTION AND REMEDIATION OF EMERGING ENVIRONMENTAL POLLUTANTS [Research]

Fri, 6 Mar 2026 15:06:15 GMT

George, C., M.S. Christo, S. Jha, M. Harshitha, J.C. Vidyashree, M. Dinamani, and H.K. Ramaraju. Microchemical Journal 221:116936(2026)

Carbon allotropes were synthesized and functionalized to enhance key electrochemical properties like surface area, electrical conductivity, and the kinetics of electron transport to identify and remove emerging contaminants. The nanostructures were integrated into sensor electrodes using field-effect transistor and chemiresistor-type configurations. The devices established exceptional sensitivity and selectivity, achieving detection limits in the nanomolar spectrum for a range of pollutants, including pesticides and heavy metals. Surface modification with bio-recognition elements such as aptamers and enzymes enabled selective binding and efficient signal transduction. The electrochemically active carbon surfaces facilitated adsorption and electrocatalytic degradation processes, permitting the same platform to perform detection and treatment. To facilitate simultaneous contamination identification and onsite environmental cleanup, electroactive carbon surfaces absorb contaminants and accelerate their destruction. Advanced characterization methods, including Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy, were used to assess the sensor's shape, chemical bonding properties, and performance. In situ remediation with real-time monitoring offers a portable, cost-effective, and sustainable approach to environmental protection. Results establish the potential of multifunctional carbon nanomaterial-based electrochemical systems to address critical challenges in environmental sensing and contaminant remediation. https://www.sciencedirect.com/science/article/pii/S0026265X26001360/pdfft?casa_token=H4lnapaoFkIAAAAA:oWn9Aa1CWtAhHvd8h5LJneAB4LCRVmp2cjpXqt4UaRYtgrcDiFqgk2QkuSo3OkjKX6JcnG22Hg&md5=2834c97d1a021d5034a46c6b627f7c62&pid=1-s2.0-S0026265X26001360-main.pdf

AIR BUBBLING ASSISTED SOIL WASHING TO TREAT PFAS IN HIGH ORGANIC CONTENT SOILS [Research]

Fri, 6 Mar 2026 15:05:58 GMT

Londhe, K., and A.K. Venkatesan. | Environments 12(1):20(2025)

A study explored the use of a novel process where soil washing was combined with air bubbling (or foam fractionation) to aid in PFAS removal from high organic carbon (OC)-content soil (~4-20%). Treatment with air bubbling of high OC soil (~20%) with PFBS and PFOA did not enhance removal, as they featured low surface activity. An improvement in PFOS extraction from 27% to 42% was observed with bubbling, consistent with the higher surface activity of PFOS compared to PFOA and PFBS. PFDA was irreversibly adsorbed to the high OC soil and was not removed efficiently by both bubbling and soil washing. A slight improvement in PFDA removal (6-13%) was observed when a co-surfactant (cetyltrimethylammonium chloride) was added and when the OC content was reduced to ~4% by the addition of nonorganic sand to the contaminated soil before soil washing. This suggests that the interaction of PFDA with OC was the dominant factor determining its extraction from soil. Results indicated that soil washing alone was sufficient to remove short-chain PFAS from soil. Although bubbling had a mild effect on the removal of some long-chain PFAS from the solution, it did not help in the overall removal of PFAS from high OC soil, highlighting the difficulty in the treatment of high OC-content soil and that immobilization of PFAS would be an ideal approach in managing such contaminated sites. This article is Open Access at https://www.mdpi.com/2076-3298/12/1/20.

EXPLORATION OF PFAS MASS DISCHARGE IN STORMWATER VERSUS GROUNDWATER: TECHNICAL AND REGULATORY CONSIDERATIONS [Research]

Fri, 6 Mar 2026 15:05:44 GMT

Newell, C.J., J.D. Gamlin, G.J. Garvey, H.S. Rifai, G.O. Grundy, M. Gupta, M. Wang, N.W. Johnson, H. Javed, and M.Q. Lentz. | Remediation 36(1):e70052(2025)

A study analyzed the environmental criteria that may drive stormwater remediation, modeled the stormwater hydrologic response of hypothetical AFFF sites, compiled PFOS concentration data in stormwater, and compared the potential PFOS mass discharge in stormwater versus groundwater. Typical stormwater mass discharge of PFOS was relatively smaller than groundwater contributions at AFFF sites. However, given the faster impact timescale of stormwater movement and the variability in receiving water types and uses, many AFFF sites may require some form of stormwater management. The paper presents a series of potential regulatory approaches for PFAS-impacted stormwater, including expansion of existing regulatory programs, use of best management practices, individual site mass discharge limits, and watershed-scale PFAS mass balance approaches. This article is Open Access athttps://onlinelibrary.wiley.com/doi/10.1002/rem.70052.

ASCORBIC ACID STABILITY AND PH TESTING TO SUPPORT RWM-018 PILOT SCALE WELLHEAD TREATMENT SYSTEM FEASIBILITY DETERMINATION [Research]

Fri, 6 Mar 2026 15:05:27 GMT

VerMeulen, H., E. Koelker, and S. Fuentes. Savannah River National Laboratory (SRNL) Report SRNL-STI-2025-00578, 24 pp, 2025

Historical in situ chemical oxidation (ISCO) injections of potassium permanganate and sodium persulfate left residual oxidant concentrations in the A/M-Area groundwater system at the Savannah River site. ISCO events targeted DNAPLs through strong oxidant injections within plume zones upgradient of current groundwater recovery wells RWM-008 and RWM-018. These residual oxidants could significantly impede the operation of the mercury removal system needed to meet NPDES permit requirements for the ongoing P&T system that hydraulically controls portions of the A/M-Area plume. Effluent-treated groundwater from this system is discharged to surface water at the receiving outfall of the M-1 Air Stripper. To prevent interference of the M-1 Air Stripper system by residual oxidants, groundwater recovery was ceased at well RWM-018. Oxidant transport modeling in the A/M-Area from ISCO estimated that the potential oxidant load contributed by RWM-018 could be as high as 120 mg/L. It is also possible that oxidants may contribute via pumping at well RWM-008 as residual oxidants within the aquifer migrate toward its zone of influence. SRNL conducted research to investigate potential pre-treatment chemicals to neutralize the residual oxidants before reaching the M-1 Air Stripper to allow for resumed groundwater recovery at RWM-018 and continued pumping at RWM-008. Deployment of ascorbic acid for neutralization of residual oxidants at RWM-018 (and possibly RWM-008) is recommended based on results from previous reductant testing. For a maximum estimated oxidant load at RWM-018, a well-head treatment system would need to dose about 400 gals ascorbic acid per month to ensure complete neutralization. A second system with an additional reagent should also be considered for deployment at RWM-008. https://www.osti.gov/servlets/purl/2997611

MULTI-APPROACH DATA PROCESSING WORKFLOW TO HELP CLOSING THE MASS BALANCE OF PFAS IN THE ENVIRONMENT [Research]

Fri, 6 Mar 2026 15:05:07 GMT

Shrestha, O., J. Dahl, T. Matsubara, and R. Marfil-Vega. Environmental Measurement Symposium, August 4-8, St. Louis, MO, 35 slides, 2025

An untargeted LC-MS method employing a sensitive, high-mass-accuracy quadrupole time-of-flight (QToF) instrument was used to participate in the PFAS NTA Interlaboratory Study organized by NIST in 2024. This technique, coupled with a novel data-processing approach, enables comprehensive non-targeted PFAS screening that helps close the mass balance of PFAS in the environment. Three unknown samples (A, B, and C) obtained from NIST were analyzed to identify PFAS. A data-dependent acquisition (DDA) method in both positive and negative ionization modes was implemented using QToF mass spectrometry to expand the chemical space covered with the method. Multi-approach data processing included identifying PFAS compounds using NIST Library Match, the NIST suspect list, FluoroMatch, and LabSolutions. The EPA 1633 PFAS standard mix was used to validate m/z trigger settings for the DDA method. The NIST MS2 library was converted into a software-compatible format to facilitate accurate spectrum matching. Identification through NIST Suspect Match relied on common product ions, neutral losses, and isotope Score, with a mass error threshold of less than 5 ppm. FluoroMatch analysis incorporated its built-in PFAS library and algorithms, utilizing Kendrick Mass Defect plots to identify PFAS and related families. Results were dereplicated, and PFAS were identified and scored according to NIST-defined criteria. Samples A, B, and C had 40, 57, and 105 negative PFAS matches and 9, 44, and 29 positive matches. The presentation demonstrates the workflow and how the multi-data approach benefits PFAS identification. https://apps.nelac-institute.org/nemc/2025/docs/presentations/pdf/8-4-25-Emerging%20Environmental%20Applications%20for%20High%20Resolution%20Mass%20Spectrometry-2.01-Shrestha.pdf

FIELD DEMONSTRATION OF POLYMER STABILIZED ACTIVATED CARBON FOR IN SITU TREATMENT OF PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS)-IMPACTED GROUNDWATER [Demonstrations]

Fri, 6 Mar 2026 15:04:52 GMT

Hatton, J., P.-F. Yan, C. Liu, S. Jo, J. Popovic, B.L. Rhiner, J. Wong, M. Mitchek, J. Li, W.A. Arnold, M.F. Simcik, and K.D. Pennell.
Journal of Hazardous Materials 499:140292(2025)

A field demonstration of a polymer-stabilized activated carbon (colloidal carbon product [CCP]) was conducted using a "push-pull" test, consisting of a "push" phase (CCP injection) and a "pull" phase (withdrawal of treated groundwater), to assess the effectiveness of the treatment technology. A lab-scale aquifer cell experiment using site aquifer materials and simulated groundwater demonstrated 90.9 to >?99.9% removal of all six tested PFAS by CCP injection. For the field-scale test, a total of 1,900-L CCP was injected into a 2.4-meter interval, and 4,750?L of water were extracted from the treated interval, with extractions conducted at 3- and 10-month post-injection. PFAS concentrations were reduced by up to four orders-of-magnitude, from >?50,000?ng/L total PFAS to below individual detection limits in samples collected 10 months post-injection. An economic analysis indicates that the operating costs of the CCP system would be less than half of a comparable P&T system. Findings demonstrate that CCP injection is a practical, efficient, and cost-effective in situ remediation strategy for addressing PFAS-impacted groundwater plumes. https://www.sciencedirect.com/science/article/pii/S0304389425032121/pdfft?md5=d7197e9f98aa8d951affd8edb14ecbb6&pid=1-s2.0-S0304389425032121-main.pdf

INNOVATIVE PHYTOMANAGEMENT SYSTEMS BY COMBINING MISCANTHUS AND SWITCHGRASS WITH BIOSTIMULANTS TO ENHANCE MICROBIAL DIVERSITY AND SOIL REMEDIATION [Demonstrations]

Fri, 6 Mar 2026 15:04:37 GMT

Iqbala, Y., B. Mua, Z. Yia, W. Zegada-Lizarazuc, M. Von Cosseld, P. Peronic, E. Alexopouloue, A. Montic, E.G. Papazoglouf, T. Fua, and S. Xuea.
Industrial Crops and Products 234:121610(2025)

A technology with enhanced phytoremediation capacity that combines miscanthus and switchgrass with biostimulants to promote beneficial soil bacteria and fungi was evaluated through field trials on a metal-polluted soil. Crop growth was compared under two different biostimulants treatments and a control, considering biomass yield, morphological parameters, soil physicochemical and biological properties. Biostimulant treatments compared with control positively influenced crop biometric traits and increased biomass yield up to 3?t/ha (+54%) and 9?t/ha (+35%) for miscanthus and switchgrass, respectively, in the second establishment year. Biostimulants treatment HAM (humic acid combined with mycorrhizae) performed best by reducing the metal CaCl2-available fraction in both miscanthus and switchgrass plots, with the exceptions of Pb in switchgrass and Cu in miscanthus. The study corroborated that both factors under study, i.e., crop type and biostimulant applications, have influenced the soil microbiome structure. Compared with the control group, biostimulants HAM treatment increased Bacillus abundance by 44% in miscanthus and Candidatus Solibacter by 200% in switchgrass. In the case of fungi, the biostimulants HAM treatment promoted the relative abundance of Fusarium in the rhizospheres of both miscanthus and switchgrass. Findings suggest that selecting the right crop and biostimulants application can modulate the rhizosphere environment, consequently enhancing the effectiveness of phytomanagement technologies. https://www.sciencedirect.com/science/article/pii/S0926669025011562/pdfft?md5=4348870ee2d1470fdaf90d6bd2b663f3&pid=1-s2.0-S0926669025011562-main.pdf

COMBINING MICROBIOLOGICAL, CHEMICAL, AND ABIOTIC PROCESSES FOR SIMULTANEOUS TREATMENT OF CVOCS AND HEAVY METALS [Demonstrations]

Fri, 6 Mar 2026 15:04:23 GMT

Lakhwala, F. and A. Seech. | AEHS Foundation 41st Annual International Conference on Soils, Sediments, Water and Energy 20-23 October, Amherst, MA, 33 slides, 2025

Biogeochemical reduction (BGCR) combines natural microbiological, chemical, and abiotic processes such as enhanced reductive dechlorination (ERD) and in situ chemical reduction (ISCR) to enhance cVOC degradation and sequester toxic metals. This presentation describes the synergistic effect of these processes and provides representative site data from a field-scale application for the removal of chlorinated ethenes, cadmium, nickel, and zinc. https://s3.amazonaws.com/amz.xcdsystem.com/A51108D5-FA2F-2B6D-01D92AC0F42DCE3B_abstract_File26129/PDFofPresentation_42_1019090403.pdf

FINAL VERIFICATION STUDY/PILOT TEST COMPLETION REPORT INSTALLATION RESTORATION SITE 14 ALAMEDA POINT, ALAMEDA, CA [Demonstrations]

Fri, 6 Mar 2026 15:04:08 GMT

Naval Facilities Engineering Systems Command Southwest, 154 pp, 2025

A pilot study at IR Site 14 in Alameda evaluated the effectiveness of an in situ colloidal activated carbon (CAC) barrier using PlumeStop® to reduce PFAS mass flux to the Oakland Inner Harbor. The verification effort included bench-scale column testing, passive flux meter (PFM) assessments, continuous soil coring, discrete groundwater sampling, and a clear-water injection test to refine barrier design and injection parameters. Column results showed that 0.5% CAC reduced total PFAS by more than two orders of magnitude, while 2.0% CAC achieved greater than three orders of magnitude reduction, leading to the selection of variable CAC concentrations (2.5%, 5.0%, and 7.5%) based on PFAS mass loading across treatment zones. The barrier was installed using 290 direct-push injection points between 3 and 17 feet bgs, and 12 performance monitoring wells were installed along three transects to evaluate effectiveness. During the first year of post-injection monitoring, PFOS and PFOA concentrations generally decreased by more than 90% within the barrier and by 40-50% or more downgradient, with some wells showing reductions from over 100,000 ng/L to near non-detect levels. PFM data confirmed significant reductions in contaminant mass flux, and groundwater elevation monitoring indicated no mounding or adverse hydraulic impacts. Overall, the pilot study demonstrated that the 7.5% CAC barrier effectively reduced PFAS migration toward the harbor and provided critical data to support long-term remedial design decisions. https://alamedapointenviro.com/wp-content/uploads/2025/07/site-14-verification-study_pilot-test-rpt.pdf

REMEDIATION OF PFAS-IMPACTED SOLIDS [Cleanup News]

Fri, 6 Mar 2026 15:03:53 GMT

Popovic, J. and J. Kornuc. NAVFAC Remediation Innovative Technology Seminar, 74 slides, 2025

The presentation provides a comprehensive overview of approaches for managing PFAS-impacted soil and solids, focusing on both established practices and emerging treatment technologies. The core of the presentation compares treatment technology categories, including thermal desorption, smoldering combustion, soil washing, and stabilization/solidification, summarizing their readiness levels, advantages, limitations, and costs for handling PFAS-laden materials. Case studies are described to demonstrate how the technologies perform in practice. At Naval Auxiliary Landing Field Fentress, ~14 tons of soil with ~30 µg/kg PFAS was treated using stabilization followed by landfill disposal, with straightforward waste profiling and low cost. At Naval Station Newport, >52,000 tons of excavated soil with low PFAS concentrations (≤~5 µg/kg) were managed by segregating loads and disposing across multiple landfills with differing PFAS limits; this effort had substantial total costs and required extensive waste characterization. A small PFAS investigation-derived waste soil case at Cutler Site 10, NSA Fire Station, was disposed of as non-hazardous PFAS material in a landfill after waste profiling, highlighting logistical challenges in remote locations. An ex situ pilot-scale thermal desorption project at Joint Base Elmendorf Richardson treated ~2,000 yd³ of soil to below both EPA residential regional screening levels and Alaska state cleanup criteria. Smoldering combustion tests at the same base showed >99.9% reduction in PFAS in treated soils, with most fluorine retained in stable forms like calcium fluoride and minimal emissions of PFAS or hydrofluoric acid, indicating effective destruction mechanisms beyond simple removal. The presentation concludes with guidelines for selecting and implementing PFAS solids treatment technologies, emphasizing protectiveness, historical data use, bench and pilot studies, regulatory coordination, and contingency planning, noting that PFAS solids management remains an evolving challenge with limited fully mature destruction technologies available. https://exwc.navfac.navy.mil/Portals/88/Documents/EXWC/Restoration/er_pdfs/rits/2025/RITS%202025_PFAS%20Solids%20Treatment_Final.pdf?ver=O13O_k822K6k7Krm4C876Q%3d%3d

NATURAL ATTENUATION- INNOVATIVE AND OBVIOUS [Cleanup News]

Fri, 6 Mar 2026 15:03:36 GMT

Knox, J.N. Northwest Remediation Conference, 20 October, Tacoma, WA, 12 slides, 2025

The scientific basis, regulatory framework, and practical implementation of monitored natural attenuation (MNA) are explained as a groundwater remediation strategy, particularly for chlorinated solvent sites. The presentation outlines regulatory expectations, the importance of source control prior to MNA selection, plume stability analysis, and the use of statistical trend evaluation and contingency triggers to ensure protectiveness. The case study focuses on a large, complex chlorinated solvent contamination site covering >300 acres with five or more intermingled plumes across three aquifer zones, divided by regulatory boundaries and monitored with well triplets to characterize vertical plume profiles. Source control and removal actions were carried out for all identified source areas before considering MNA as a remedial strategy. Lines of evidence supporting MNA included spatial degradation trends (significant breakdown of parent compounds like TCE into daughter products such as vinyl chloride and ethene), limited temporal decreases, and favorable geochemical conditions indicating natural biodegradation processes. A conceptual site model was developed to delineate source areas, the extent of contamination, and exposure pathways, which supported the observation of stable to shrinking overall plume behavior with some localized expanding zones, and molar comparisons showing elevated daughter products downgradient. The remedy also incorporated institutional controls and contingency triggers that would initiate additional actions if statistically significant increasing trends were detected at compliance points near discharge to the Lower Duwamish Waterway, reflecting risk-based management tied to ecological receptors. Long-term monitoring and financial assurance were highlighted as essential due to the extended timeframes required for attenuation processes to achieve regulatory goals. https://nwremediation.com/wp-content/uploads/B3_KNO1.pdf

SUPPLEMENTAL CONTAMINANT SOURCE AND CREEK SEDIMENT REMEDIATION AT A PREVIOUSLY REMEDIATED SUPERFUND SITE, PENNSYLVANIA, U.S.A. [Cleanup News]

Fri, 6 Mar 2026 14:58:52 GMT

Reese III, W.J. and N. Rashid. | SETAC North America 46th Annual Meeting, 16-20 November, Portland, OR, abstract only, 2025

The Whitmoyer Laboratories Superfund site is a former pharmaceutical manufacturing facility contaminated with arsenic. Previous remediation included excavation and off-site disposal of soil impacted with high concentrations of arsenic, consolidation (under the cap) of soil with lower arsenic impacts, construction of a 2-ft thick permeable soil cap to prevent direct contact with residual subsurface arsenic-impacted soil, institutional controls, and hydraulic control and treatment of impacted groundwater. Post-remedy sediment monitoring revealed an area below the canal-creek confluence with elevated arsenic levels in the surficial creek sediment. This area was likely either overlooked during the original remedial investigations, due to the spatial scale of sediment data collected, or reflects newly contaminated sediments due to potential uncontrolled source(s) of arsenic loading to the creek. Supplemental sediment investigations were performed to better understand the horizontal and vertical extent of the impacted sediments. Numerous contemporaneous investigations revealed that overburden shallow groundwater with elevated arsenic has the potential to seasonally discharge to the creek from the southern bank at a former soil hot spot area, as overburden groundwater was not fully controlled by the bedrock pumping wells of the groundwater recovery system. To address this new source of arsenic to Tulpehocken Creek, an overburden groundwater interceptor trench system was constructed. Remedial alternatives are being evaluated to remove the area of contaminated sediments from the creek, cap the underlying impacted soils, and reconstruct the creek bed to mitigate the potential for erosion and recontamination of the new cap. The presentation focuses on the methods used to locate and delineate the area of contaminated creek sediment and determine the supplemental remediation required, including the overburden groundwater interceptor trench system, as well as the pending streambed remedial work. See site documents for more information: https://cumulis.epa.gov/supercpad/SiteProfiles/index.cfm?fuseaction=second.scs&id=0300643&doc=Y&colid=30873®ion=03&type=SC

FY26 WILLAPA SEDIMENT CHARACTERIZATION SERVICE [Market/Commercialization]

Fri, 6 Mar 2026 14:58:30 GMT

US Army Corps of Engineers (USACE) Engineer Northwestern Division
Contract Opportunities on SAM.gov PANNWD26P0000027927, 2026

This solicitation is being released as a Total Small Business Set-Aside under NAICS code 541620. Market research is being conducted to determine contractor capabilities for sediment characterization in Willapa Bay, Washington. The contractor will be expected to provide all personnel, equipment, facilities, transportation, tools, materials, supervision, and other items and non-personal services necessary to perform the tasks for a sediment characterization in Willapa Bay as defined in this Performance Work Statement (PWS). Work will include preparing a sampling and analysis plan (SAP) suitable for submission for approval, sampling and characterizing the sediments in the proposed dredging area as described in the SAP, and preparing a report to document characterization results that can then be used by the Dredged Material Management Program (DMMP) to make a suitability determination. The PWS includes preparation of the SAP; sampling and testing of dredged material; data collection and analysis; and report preparation. The contractor must possess the following experience:

Performance of sediment characterization in coastal/marine environments.

Ability to generate sampling and analysis plans in accordance with the Dredged Material Management Program (DMMP) User Manual.

Ability to collect and process sediment core and grab samples and analyze the sediment samples for chemical and biological laboratory testing in accordance with DMMP guidance.

Ability to review, interpret, and synthesize chemical and biological sediment data succinctly in a comprehensive data report that includes tables and figures.

Ability to generate, review, and upload electronic data deliverables in the Washington State Environmental Information Management (EIM) database format for acceptance and publication in the EIM database.

https://sam.gov/workspace/contract/opp/1c622b57294b4b6ea9bc1348c3835529/view

ENVIRONMENTAL LABORATORY SERVICES [Market/Commercialization]

Fri, 6 Mar 2026 14:58:02 GMT

Us Army Corps of Engineers (USACE) Engineer Division, Great Lakes and Ohio
Contract Opportunities on SAM.gov PANGLR26P029694, 2026

ENVIRONMENTAL LABORATORY SERVICES
US Army Corps of Engineers (USACE) Engineer Division, Great Lakes and Ohio
Contract Opportunities on SAM.gov
The USACE Chicago District is issuing this sources sought synopsis as a means of conducting market research to identify parties having an interest in and the resources to support the requirement for environmental laboratory services for water and sediment sampling analysis. The intention is to procure these services on a competitive basis. Based on the responses to this sources sought notice/market research, this requirement may be set-aside for small businesses (in full or in part) or procured through full and open competition, and multiple awards may be made. All Small Business Set-Aside categories will be considered. Telephone inquiries will not be accepted or acknowledged, and no feedback or evaluations will be provided to companies regarding their submissions. https://sam.gov/workspace/contract/opp/bc6c27c2cc114aafb9bd06ac387f8e83/view

PRE-SOLICITATION NOTICE AND DRAFT RFP FOR ENVIRONMENTAL REMEDIATION SERVICES (ERS) SINGLE AWARD TASK ORDER CONTRACT (SATOC) FOR THE SHAW AIR FORCE BASE OPTIMIZED REMEDIATION CONTRACT (ORC) [Market/Commercialization]

Fri, 6 Mar 2026 14:57:43 GMT

United States Army Corps of Engineers (USACE), Engineer Division South Atlantic
Contract Opportunities on SAM.gov W912HN26RA009, 2026

This pre-solicitation notice and Draft RFP are for a $40M Environmental Remediation Services (ERS), Single- Award Task Order contract (SATOC) for the Shaw Air Force Base Optimized Remediation Contract (ORC) for the USACE Savannah District. This acquisition is being offered as a 100% set-aside for small business competition, under NAICS 562910, and will result in a Firm Fixed Price Contract Award. This pre-solicitation notice provides industry with information prior to the issuance of the RFP and an opportunity for industry to comment on the Draft RFP. The objective of the Shaw Remediation Project is to achieve a site closure as defined in the Shaw Hazardous Waste RCRA Permit for unrestricted residential use. The Shaw AFB ORC consists of 18 Installation Restoration Program (IRP) sites, Operations and Maintenance for two large Groundwater Treatment Plants, and zero Military Munitions Response Program (MMRP) sites. POs include 11 RA-O Sites, three IRA-O Sites, and four LTM Sites. Eleven sites have a PO of Alternative Objectives as well as RC or SC. See the Draft RFP for the full SATOC and Seed Project Performance Work Statements. The ordering period is seven years for the base period and one six-month option period pursuant to FAR 52.217-8. The final approved solicitation will be issued in electronic format only and is anticipated to be available on or about 12 March 2026. https://sam.gov/workspace/contract/opp/7320f6b3a63044198763ef1de0e9abf3/view

EVALUATION ON THE BIOLOGICAL ASPECT OF PLANT, CONTAMINANT TYPES AND APPLICATION OF PHYTOREMEDIATION FOR ENVIRONMENTAL AND ECONOMICAL SUSTAINABILITY [General News]

Mon, 23 Feb 2026 14:42:21 GMT

Ghadge, S.A., P. Trivedi, B. Kumar. M, V. Singh, R. Mondal, A. Krishna V, and D.S. Painkra.
Journal of Advances in Biology & Biotechnology 29(1):75-95(2026)

The phytoremediation potential of hyperaccumulators, grasses, woody trees, aquatic plants, and food crops against heavy metals (Pb, Cd, As, Cr, Ni, Zn), organic pollutants (PAHs, PCBs, pesticides), radionuclides, pharmaceuticals, microplastics, and nutrient-induced eutrophication is systematically assessed in this review. It explains key physiological and molecular processes, including metal uptake via ZIP and HMA transporters, detoxification through phytochelatins, metallothioneins, vacuolar sequestration, root exudate-mediated mobilization, and microbial degradation. Technological advances such as CRISPR/Cas-based genetic modification, nano-enabled phytoremediation, synthetic plant-microbiome consortia, remote sensing, GIS-driven monitoring, and phytomining for metal recovery are emphasized. Field-based applications in mining zones, agricultural soils, wetlands, oil-spill areas, and industrial sites demonstrate significant remediation efficiency and ecological restoration. Although challenges persist, including slow remediation rate, pollutant toxicity to plants, biomass disposal, seasonal variability, lack of awareness, and limited policy incentives, economic assessments indicate phytoremediation is 5-10 times more cost-effective than conventional technologies. Future priorities involve deploying climate-resilient species, conducting long-term field trials, promoting circular economy-based biomass utilization, integrating phytoremediation with agroforestry, digital monitoring, and fostering interdisciplinary and international collaborations. https://journaljabb.com/index.php/JABB/article/view/3508/9284

BIODEGRADATION OF PER- AND POLYFLUOROALKYL SUBSTANCES: MECHANISMS, CHALLENGES, AND EMERGING STRATEGIES FOR SUSTAINABLE REMEDIATION [General News]

Mon, 23 Feb 2026 14:42:02 GMT

Nasrollahpour, S., S. Purewal, R. Kumar Das, and S. Kaur Brar.
Environmental Science Water Research & Technology 12:397(2026)

This review provides a comprehensive synthesis of current knowledge and outlines strategic directions to advance PFAS biodegradation research and its practical implementation. Innovative strategies, including enzyme immobilization, phytoremediation, hybrid chemical-biological systems, and machine learning-based predictive modeling, are evaluated for their potential to enhance treatment efficiency. Remaining challenges include an incomplete understanding of metabolic pathways and limited scalability. A future research roadmap is proposed to integrate metabolic engineering, system optimization, and field-scale validation toward effective, sustainable PFAS biodegradation. https://pubs.rsc.org/en/content/articlepdf/2026/ew/d5ew00888c

A CRITICAL REVIEW OF SURFACTANT-ENHANCED AQUIFER REMEDIATION FOR DNAPLS: RESIDUAL MORPHOLOGY, GOVERNING FACTORS, AND REMOVAL MECHANISMS Huang, C., B. He, Z. Liu, Z. Zhou, and Y. Li. Environmental Geochemistry and Health 48:134(2026) This review analyzes DNAPL migration and retention, identifying the residual phase as the critical barrier to successful remediation. Surfactant-enhanced aquifer remediation (SEAR) performance critically depends on surfactant properties, aquifer media, and hydrodynamic conditions, leading to variable outcomes. A comprehensive analysis of residual phase DNAPL migration mechanisms reveals that DNAPL movement is predominantly controlled by the interplay of gravitational, capillary, and viscous forces. The article presents a force-balance analytical framework connecting DNAPL displacement to key remediation parameters. Remediation success relies on identifying and regulating dominant forces under site-specific conditions, while aquifer heterogeneity and coupled parameters add complexity in three-dimensional field settings. Thus, multi-parameter interactions need systematic evaluation. Large-scale research on multi-parameter coupling mechanisms is currently lacking, and future efforts should address this to advance precise DNAPL remediation strategies. [General News]

Mon, 23 Feb 2026 14:41:48 GMT

Huang, C., B. He, Z. Liu, Z. Zhou, and Y. Li.
Environmental Geochemistry and Health 48:134(2026)

This review analyzes DNAPL migration and retention, identifying the residual phase as the critical barrier to successful remediation. Surfactant-enhanced aquifer remediation (SEAR) performance critically depends on surfactant properties, aquifer media, and hydrodynamic conditions, leading to variable outcomes. A comprehensive analysis of residual phase DNAPL migration mechanisms reveals that DNAPL movement is predominantly controlled by the interplay of gravitational, capillary, and viscous forces. The article presents a force-balance analytical framework connecting DNAPL displacement to key remediation parameters. Remediation success relies on identifying and regulating dominant forces under site-specific conditions, while aquifer heterogeneity and coupled parameters add complexity in three-dimensional field settings. Thus, multi-parameter interactions need systematic evaluation. Large-scale research on multi-parameter coupling mechanisms is currently lacking, and future efforts should address this to advance precise DNAPL remediation strategies.

BIOENGINEERED ENDOPHYTE-INTEGRATED BIOSENSORS: A NEW FRONTIER IN ENVIRONMENTAL MONITORING AND REMEDIATION [General News]

Mon, 23 Feb 2026 14:41:33 GMT

Dhar, I., A. Sharma, A. Kumawat, A. Dadhich, H. Priyadarshi, L. Sharma, and M.M. Sharma. Experimental and Computational Advances in Materials p 339-382, 2026

This book chapter examines integrated approaches that combine biological materials, such as plant endophytes and enzyme systems, with nanomaterial-based biosensors for real-time environmental monitoring. Endophytes, known for their metal chelation, enzymatic activity, and stress tolerance, serve dual roles in contaminant detection and remediation. Coupled with green synthesis of nanoparticles and phytoremediation, these biological systems contribute to low-impact, resource-efficient cleanup processes. Advances in material characterization, nanostructure design, and surface engineering have improved biosensor sensitivity and selectivity across complex environmental matrices. In addition, computational tools such as life cycle assessment, predictive modeling, and machine learning aid in optimizing biosensor performance and assessing long-term environmental impacts. The chapter highlights how the convergence of experimental innovations and computational methodologies in materials science enables the design of smart, multifunctional systems for pollution management. Emphasis is placed on sustainability, adaptability, and real-world applicability, aligning with the broader goals of circular economy and green engineering. The interdisciplinary perspective supports the ongoing transition toward environmentally responsible technologies within the framework of materials science and engineering.

EFFECT OF LOW-TEMPERATURE THERMAL DECHLORINATION ON POLYCHLORINATED NAPHTHALENES IN MUNICIPAL SOLID WASTE INCINERATION FLY ASH: CONCENTRATIONS, CONGENER PROFILES, AND DIOXIN-LIKE TOXICITY [Research]

Mon, 23 Feb 2026 14:41:21 GMT

Ito, K., S. Mizutani, and Y. Yabuki. | Chemosphere 395:144834(2026)

The concentrations, congener profiles, and dioxin-like toxicities of polychlorinated naphthalenes (PCNs) and PCDD/Fs were evaluated in municipal solid waste incineration (MSWI) fly ash before and after low-temperature thermal dechlorination (LTD) at five full-scale facilities. LTD consistently induced stepwise dechlorination, reducing the average chlorination degree of PCNs by 1.1-1.5 points. However, total PCN concentrations exhibited facility-dependent behavior: decreases of 98-99% were observed at some facilities, whereas others showed increases of 230-370% relative to pre-LTD levels. The mass increase is plausibly attributed to the reformation of low-chlorinated PCNs on the fly ash carbon surfaces during the cooling phase. Despite these contrasting changes in mass concentrations, PCN-derived dioxin-like toxicity (PCN-TEQ) decreased substantially at all facilities (35-99% reduction). This robust detoxification occurred because LTD preferentially degrades the highly chlorinated congeners (e.g., 1,2,3,6,7,8-hexaCN and 1,2,3,4,6,7-hexaCN) that dominate PCN-TEQ. The PCN contribution to total toxicity consequently declined from 0.18 to 0.45% before LTD to 0.03-0.30% afterward. For PCDD/Fs, LTD generally lowered mass concentrations, although PCDD/F-TEQ reductions varied among facilities due to differences in residual high-TEF congeners. Findings unequivocally demonstrate that LTD is a highly effective strategy for mitigating the dioxin-like toxicity associated with PCNs in MSWI fly ash. Results enhance understanding of chlorinated pollutant transformation during full-scale LTD operation and support its optimization for safer MSWI fly ash management.

IMPACT OF MULTIPLE HVAC SYSTEMS ON INDOOR AIR VOC AND RADON CONCENTRATIONS FROM VAPOR INTRUSION DURING SEASONAL USAGE [Research]

Mon, 23 Feb 2026 14:40:25 GMT

Zimmerman, J.H., A. Williams, B. Schumacher, C. Lutes, R. Warrier, B. Cosky, B. Thompson, C.W. Holton, and K. Bronstein. | Atmosphere 16(4):378(2025)

Samples were collected between December 2020 and April 2022 at six commercial buildings in Fairbanks, Alaska, to evaluate VI risks and estimate the reasonable maximum exposure (RME) to the occupants. The types of samples collected included indoor air (IA); outdoor air; subslab soil gas; soil gas; indoor radon; differential pressure; indoor and outdoor temperature; heating, ventilation, and air conditioning (HVAC) parameters; and other environmental factors. The buildings near the VOC source/release points showed less variability in indoor air concentrations of TCE and PCE compared to buildings located farther downgradient from the contaminated groundwater plume. The VOC data pattern for the source area buildings shows an outdoor air temperature-dominated behavior for indoor air concentrations in the summer season. HVAC system operations had less influence on long-term indoor air concentration trends than environmental factors, which was supported by similar indoor air concentration patterns independent of location within the plume. Using soil temperature and indoor/outdoor temperatures as indicators and tracers (I&Ts) across the plume as predictors of the sampling period could produce a good estimation of the reasonable maximum exposure for the building occupants. Results, which show the use of soil temperature and indoor/outdoor temperatures as I&Ts, will help advance investigative methods to evaluate vapor intrusion in similar settings and thereby improve the protection of human health in indoor environments. This article is Open Access at https://www.mdpi.com/2073-4433/16/4/378.

ASSESSMENT OF PER- AND POLYFLUOROALKYL SUBSTANCES (PFAS) IN CONSUMER FOOD PACKAGING [Research]

Mon, 23 Feb 2026 14:40:11 GMT

Stroski, K. and Y. Sapozhnikova. | Chemosphere 395:144824(2026)

A new method was developed and validated to analyze 73 PFAS from 15 different classes in paper and plastic food contact materials (FCMs) based on methanolic extraction and liquid chromatography-mass spectrometry (LC-MS/MS) analysis. The method was validated at three spiking levels with five replicates per level. Acceptable recoveries and repeatability were achieved for 96-100% of analytes between various spiking levels and food packaging materials. The validated method was used to test 66 paper and plastic food packaging materials in direct contact with the previously tested food samples of chicken, pork, beef, and catfish purchased from grocery stores in the U.S. Nine PFAS were detected in the samples: 8:2 FTSA, 6:2 diPAP, 8:2 diPAP, diSAmPAP, PFBA, PFHxA, PFOA, PFBS, and PFOS with ?PFAS concentrations ranging from 0.11 to 16.3 ng/g. At least one PFAS was detected in 64% of the samples. The most frequently detected PFAS was 6:2 diPAP found in 61% of samples, across all material types in concentrations of 0.09-10.3 ng/g. Results suggest no evidence of PFAS transfer from FCMs tested in this study to packaged food tested in a previous study.

ELECTROKINETIC MOBILIZATION OF PFAS IN SOILS: LINKING HEAD GROUP AND CHAIN LENGTH TO REMEDIATION EFFICIENCY [Research]

Mon, 23 Feb 2026 14:39:52 GMT

Dhulia, A., C. Abou-Khalil, K. Mustafa, D. Sarkar, M.C. Boufadel.
Chemosphere 396:144837(2026)

Five PFAS compounds (PFBA, PFOA, PFDA, PFOS, and FOSA) were selected to investigate the influence of molecular structure, representing variations in chain length and head group, on remediation efficiency. Electrokinetic (EK) remediation and hydraulic gradient (HG) treatments were applied to soil with organic matter contents of 5%, 30%, and 50%. PFAS removal was highly influenced by the molecular structure of the species. Both EK and HG were effective at mobilizing short-chain PFAS, which are more mobile in porewater. However, moving longer-chain or more strongly sorbing PFAS was more challenging. The compounds responded better to HG due to the stronger advective forces and may require a combination of HG and EK to achieve significant mobilization. Overall, PFOS, FOSA, and PFDA showed limited mobilization under either treatment due to their stronger sorption to soil organic matter, which restricts both electrokinetic and hydraulic transport. Findings highlight the need to align remediation strategies with PFAS physicochemical properties and soil composition to improve field-scale treatment efficiency.

DECONVOLUTING AND INTERPRETING NONTARGETED CHEMICAL DATA: A DATA-DRIVEN FORENSIC WORKFLOW FOR IDENTIFYING THE MOST PROMINENT CHEMICAL SOURCES IN RECEIVING WATERS [Research]

Mon, 23 Feb 2026 14:39:33 GMT

Shi, C., C.M.G. Carpenter, D.E. Helbling, and G.D. Jones.
Environmental Science & Technology 59(36):19307-19317(2025)

This article presents a data-driven workflow that reduces bias on existing workflows that often rely on predefined targets and known sources, by applying an unsupervised machine learning technique. Both nonmetric multidimensional scaling (NMDS) and non-negative matrix factorization (NMF) were applied on the same nontargeted chemical data set to compare their different interpretations of environmental sources. Weekly nontargeted data were collected from the Fall Creek Monitoring Station (Ithaca, NY), where daily samples were previously analyzed using source-defined models. NMF was first used to decompose the full nontargeted chemical data set into a small set of chemical factors representing distinct composition profiles. Each factor was then interpreted through (1) Spearman correlations with watershed characteristics and (2) suspect screening of high-weighted nontargeted features. In addition to confirming known anthropogenic inputs, analysis revealed potential novel sources associated with snowmelt, groundwater seepage, and seasonal hydrological dynamics. An annual shift in the chemical composition was also detected, highlighting the evolving influence of these sources. This workflow enables watershed managers to move beyond predefined sources, detect both known and emerging chemical contributors, and apply adaptive, evidence-based strategies to protect water quality under changing conditions.

PATHWAYS FOR THE MINERALIZATION OF PERFLUOROOCTANESULFONIC ACID UNDER A SMOLDERING REDUCTIVE ATMOSPHERE [Research]

Mon, 23 Feb 2026 14:39:18 GMT

Zhan, M., Z. Zhang, Y. Shan, J. Fu, P. Cai, and W. Jiao.
Environmental Science & Technology 60(4):3668-3680(2026)

In this study, PFOS smoldering degradation pathways and relative bond cleavage mechanisms were deduced from lab-scale byproduct profiles and supported by reactive force field simulations and quantum-chemical calculations. Smoldering self-sustained at a 0.79 MJ/kg calorific value and 1.5-2.5 cm/s air Darcy velocity. The removal rate of PFOS reached 98.1%, with only ?50% energy consumption compared with that of conventional incineration under equivalent degradation conditions. Investigations revealed distinct degradation pathways in smoldering compared with traditional approaches: in a CO atmosphere, early C-C bond scission and CO-coupled sulfur transformation were predicted (potentially evolving toward COS). This pathway played a dominant role in PFOS degradation, providing more efficient sulfur-group transformation, less toxic byproducts, and better compatibility with oxygen-limited conditions. Pilot-scale experiments further validated the feasibility for field applications, achieving 98.6% PFOS removal. Findings provide mechanistic insights into improved smoldering-based PFAS remediation under reductive conditions and optimization of treatment strategies toward higher efficiency and environmental safety.

ARRAY OPTIMIZATION AND PILOT VERIFICATION OF ELECTROKINETIC-ENHANCED BIODECHLORINATION SYSTEM [Demonstrations]

Mon, 23 Feb 2026 14:39:04 GMT

Yu, S.-T., Z.-T. Li, S.-Y. Yang, Q. Cai, S. Yuan, X. Song, A. Tiehm, and H.-P. Zhao.
Environmental Science & Technology 60(3):2566-2577(2026)

A comprehensive electrokinetic bioremediation (EK-BIO) lab-to-field framework was established that included lab batch experiments, array optimization, pilot-scale field validation, and life cycle assessment was established. Primarily, batch and column experiments optimized both the additive dosage strategy and electrode array configuration, favoring a 6-day preinoculation of the niche-preparing culture and a unidirectional one-dimensional electrode setup. Guided by the results, the 98-day EK-BIO pilot experiment achieved >90.0% TCE removal, with a 74.0% chloroethylene-to-ethylene conversion efficiency. Microbial community analyses further revealed a notable increase in the relative abundance of putative organohalide-respiring bacteria in the EK-BIO, ~25.6% and 34.3% higher than in bioaugmentation and electrokinetic treatments, respectively. Additionally, life cycle assessment results underscored the advantages of EK-BIO over conventional thermal remediation alternatives, with reductions in carbon emissions, energy consumption, and remediation costs. The study validated the feasibility and reliability of EK-BIO technology, supporting its advancement for the in situ remediation of organochlorine-contaminated sites.

A METHOD FOR EVALUATING THE EFFECTS OF GENTLE REMEDIATION OPTIONS (GRO) ON SOIL HEALTH: DEMONSTRATION AT A DDX-CONTAMINATED TREE NURSERY IN SWEDEN [Demonstrations]

Mon, 23 Feb 2026 14:38:50 GMT

Drenning, P., Y. Volchko, A. Enell, D.B. Kleja, M. Larsson, and J. Norrman.
Science of The Total Environment 948:174869(2025)

An accessible, scientific method for soil health assessment was developed and demonstrated for a field experiment at a DDX-contaminated tree nursery site in Sweden to evaluate the relative effects of gentle remediation options (GRO) on soil health (i.e., the 'current capacity' to provide ecosystem services [ES]). For the set of relevant soil quality indicators (SQI) selected using a simplified logical sieve, GRO treatment was observed to have highly significant effects on many SQI according to statistical analysis due to the strong influence of biochar amendment on the sandy soil and positive effects of nitrogen-fixing leguminous plants. The SQI were grouped within five soil functions (SF), and the relative effects on soil health were evaluated compared to a reference state (experimental control) by calculating quantitative treated-SF indices. Multiple GRO treatments had statistically significant positive effects on many SF, including pollutant attenuation and degradation, water cycling and storage, nutrient cycling and provisioning, and soil structure and maintenance. The SF were in turn linked to soil-based ES to calculate treated-ES indices and an overall soil health index, which can provide valuable information to decision-makers regarding the effectiveness of GRO. The experimental GRO treatment of the legume mix with biochar amendment and grass mix with biochar amendment resulted in statistically significant improvements to soil health, with overall SHI values of 141% and 128%, respectively, compared to the reference state of the grass mix without biochar (set to 100%). https://www.sciencedirect.com/science/article/pii/S0048969724050186/pdfft?md5=dc1008ed9288e834cf8e71454e49da6f&pid=1-s2.0-S0048969724050186-main.pdf

IMPLICATIONS FOR MODELING ANION EXCHANGE TREATMENT OF PERFLUOROALKYL SUBSTANCES IN DRINKING WATER AND RELATED NATURAL ORGANIC IMPACTS: A PILOT STUDY [Demonstrations]

Mon, 23 Feb 2026 14:38:24 GMT

Smith, S., D. Wahman, E. Kleiner, B. Gray, T. Sanan, E. Stebel, C. Gastaldo, E. Hughes, S. Pedigo, B. Datsov, M. Lathrop-Allen, I. Bass, J. Quinn, G. Abulikemu, J. Pressman, G. Sorial, and L. Haupert. | Water Research 288(Part B):124685(2026)

To better understand natural organic matter (NOM) impacts on PFAS removal in drinking water, this study investigated PFAS breakthrough from pilot-scale fixed-bed anion exchange columns fed a stable water quality influent with and without addition of reconstituted Ohio River water NOM at four empty bed contact times (EBCTs; 0.5-, 1.0-, 1.5-, and 2.5-min). PFAS elution order was mostly consistent with previously reported batch-derived selectivity with respect to chloride (K_x/Cl), with deviations in bed volumes to early breakthrough (BV10) attributed to molecular size-exclusion kinetic limitations. Earlier breakthroughs were observed with NOM compared to without NOM. NOM impacts on BV10 were greater for larger, later-eluting PFAS. An ion exchange column model (IEX-CM; https://github.com/USEPA/Water_Treatment_Models) was applied to evaluate correlations for estimating film mass transfer coefficient (k_L) and to estimate PFAS intraparticle diffusion coefficient (D_s) and K_x/Cl by fitting PFAS effluent data to IEX-CM simulated concentrations, resulting in most PFAS breakthrough curves being well-described by IEX-CM simulations. Some deviations from the IEX-CM were noted, including unexplained chromatographic effects on PFHxA and apparent non-adsorption hexafluoropropylene oxide dimer acid (HFPO-DA or GenX chemicals) removal, which was enhanced by increasing EBCT and the absence of NOM.

WELCOME TO THE VADOSE ZONE: THE USE OF LYSIMETERS IN THE EVALUATION OF PFAS SOURCES AT THREE SITES IN NORTHERN NEW ENGLAND [Demonstrations]

Mon, 23 Feb 2026 14:36:58 GMT

Duncan, J. | AEHS Foundation 41st Annual International Conference on Soils, Sediments, Water and Energy 20-23 October, Amherst, MA, 28 slides, 2025

Multiple lysimeters were installed at three sites in New Hampshire to evaluate potential PFAS sources, which had previously been detected in groundwater. The sampling devices provided site-specific and potentially more representative data to evaluate PFAS leaching from soil and biosolids-amended soil. The installation and use of lysimeters, along with related technical challenges, are presented. Data obtained from lysimeter-collected pore water, compared with results from co-located soil, groundwater, and/or Synthetic Precipitation Leaching Procedure (SPLP) leachate, are discussed, along with lessons learned from data analysis, particularly as they regard the development of future sampling plans. The subject sites include a school, a landfill, and a former industrial waste processing site. In each case, groundwater was suspected of being impacted by PFAS present in applied biosolids and/or soil that had been disturbed through previous remedial efforts. Results confirmed the subject soil and biosolids-amended soil as potential sources of PFAS to groundwater. These investigations have shown lysimeters to be useful sampling devices for site investigations potentially involving the transport of PFAS from soil to groundwater, while also providing valuable lessons learned for future projects. https://s3.amazonaws.com/amz.xcdsystem.com/A51108D5-FA2F-2B6D-01D92AC0F42DCE3B_abstract_File26129/PDFofPresentation_89_1020022350.pdf

LESSONS LEARNED FROM IN-SITU ACTIVATED CARBON AMENDMENT APPLICATIONS TO TREAT DIOXIN/FURAN CONTAMINATION IN THE SCANLON AND THOMSON RESERVOIRS, ST. LOUIS RIVER AREA OF CONCERN [Cleanup News]

Mon, 23 Feb 2026 14:36:42 GMT

Lehto, L., B. Leick, C. Nigrelli and M. Kern. | SETAC North America 46th Annual Meeting, 16-20 November, Portland, OR, abstract only, 2025

The Minnesota Pollution Control Agency partnered with EPA's Great Lakes National Program Office on two Great Lakes Legacy Act projects to remediate dioxin/furan contaminated sediments in the Scanlon and Thomson Reservoirs. Due to the geologic and hydrodynamic constraints of the reservoirs, remedial capping and dredging/removal were not viable remedial alternatives. The selected remedy was application of a pelletized form of powdered activated carbon (PAC) amendment to minimize uptake of contaminants from the sediment to benthic invertebrates. Approximately 238 tons of pelletized PAC were placed over a 13.7-acre area at the Scanlon Reservoir. Upon completion, the Thomson Reservoir project is projected to place 18,600 tons of pelletized PAC over ~66 acres. Pelletized activated carbon placement at this scale is a new and novel way of mitigating the bioavailability of contaminants, leading to design and implementation unknowns. Dust mitigation strategies during transfer and placement of the amendment were developed during full-scale placement at both sites. Quality assurance and quality control procedures to verify PAC placement thicknesses were independently developed for each site and modified during placement to achieve the best possible data. Accessing and placing pellets in shallow and variable water depths were also overcome with varying degrees of success. Robust plans were developed to monitor the activated carbon and in situ porewater concentrations post-placement to track remedy effectiveness. More information on the site: https://www.pca.state.mn.us/air-water-land-climate/area-of-concern-projects-and-progress

ASSESSING PLUME STABILITY TO SUPPORT TRANSITION FROM ACTIVE REMEDIATION TO MONITORED NATURAL ATTENUATION [Cleanup News]

Mon, 23 Feb 2026 14:36:26 GMT

Malkemus, D., T. Roth, and P. Zawislanski. | Northwest Remediation Conference, 20 October, Tacoma, WA, 29 slides, 2025

A scientific framework is presented for evaluating groundwater plume stability to determine when it is appropriate to transition from active remedial actions to monitored natural attenuation (MNA). The presentation describes how contaminant plumes evolve over time through natural processes such as dispersion, dilution, sorption, and biodegradation, and emphasizes the importance of understanding both concentration trends and mass-based metrics in plume assessment. Traditional concentration-based trend analysis was contrasted with mass and mass discharge approaches, noting that statistical methods alone often fail to quantify actual rates of change and plume behavior. The presentation also illustrates methods for calculating plume decay rates, bulk attenuation, mass flux, and mass discharge, and highlights their value in objectively characterizing plume stability. A detailed case study is presented, demonstrating how data on contaminant concentrations, mass removal, and trend analyses can be integrated to show decreases in plume area and discharge over time, supporting a defensible shift toward MNA. The conclusions emphasize the need for multiple lines of evidence, including trend statistics, attenuation rates, plume footprint evolution, mass discharge trends, and supporting geochemical and biological data, to establish a scientifically robust basis for transitioning to MNA while ensuring long-term protectiveness. https://nwremediation.com/wp-content/uploads/B3MALK1.pdf

DEMONSTRATION STUDY OF OZONE/ACTIVATED CARBON ENHANCED GROUNDWATER CIRCULATION WELL FOR REMEDIATION OF A PETROLEUM CONTAMINATED SITE [Cleanup News]

Mon, 23 Feb 2026 14:36:11 GMT

Zhu, X., Y. Wang, Y. Lai, Q. Shan, X. Tian, D. Zhao, R. Zhang, B. Yu, Z. Qu, and W. Chen. Water Resources 53:191-200(2026)

The improvement of traditional groundwater circulation wells by utilizing ozone for aeration while filling the upper planar hole with activated carbon, was used to determine the treatment effect of total petroleum hydrocarbons, benzene and toluene. After 192 h of groundwater ozone aeration at 30 L/min, the removal rates of total petroleum hydrocarbons, benzene and toluene in ZJ1, a circulation well in the area closer to the pollution source, reached 97.46, 99.54 and 90%. Removal rates of total petroleum hydrocarbons, benzene and toluene in ZJ2, located in the area farther away from the source of contamination, reached 99.76, 99.42 and 99.1%. The ozone/activated carbon enhanced groundwater circulation well had an impact radius of 5 m. Among the three monitoring wells, GW1, GW2 and GW3, the highest removal rate of each pollutant was found in GW3, followed by GW2, and the lowest was found in GW1. Compared to the existing groundwater circulation well, the remediation efficiency was improved in the ozone/activated carbon enhanced groundwater circulation well.

CASE STUDIES IN REMEDIATION OF EMERGING CONTAMINANTS AND CONTAMINATED SITES [Cleanup News]

Mon, 23 Feb 2026 14:35:55 GMT

Vidyasagar, G.V. and P. Keerthi. Chapter of Emerging Contaminants in the Environment, p 403-413, 2026

This chapter explores a range of real-world case studies that demonstrate effective remediation techniques contaminants, including PFAS, across global contexts. It focuses on examples such as arsenic removal in West Benga to advanced solutions like foam fractionation for PFAS treatment in Australia, the use of constructed wetlands for eliminating pharmaceutical residues in Spain, and the application of nanotechnology for chromium cleanup in the U.S. A comparative analysis sheds light on the performance, scalability, and limitations of each method. The chapter wraps up with key takeaways and forward-looking suggestions for improving future remediation practices.

PRE-SOLICITATION NOTICE AND DRAFT RFP FOR ENVIRONMENTAL REMEDIATION SERVICES (ERS) SINGLE AWARD TASK ORDER CONTRACT (SATOC) FOR THE SHAW AIR FORCE BASE OPTIMIZED REMEDIATION CONTRACT (ORC) (PRESOL) [Market/Commercialization]

Mon, 23 Feb 2026 14:35:38 GMT

U.S. Army Corps of Engineers, South Atlantic Engineer Division, Savannah District, Savannah, GA
Contract Opportunities on SAM.gov W912HN26RA009, 2026

When this solicitation is released on or about March 12, 2026, it will be competed as a total small business set aside under NAICS code 562910. The U.S. Army Corps of Engineers plans to issue a solicitation for Environmental Remediation Services under a Single Award Task Order Contract (SATOC). This contract will enable USACE to provide a full range of environmental remediation services in support of the Air Force Civil Engineer Center's Optimized Remediation Contract at Shaw Air Force Base in South Carolina. The primary objective is the remediation of soil and groundwater contaminated with a variety of substances, including PFAS, chlorinated solvents, petroleum products, and explosive constituents. The contractor must have the capability to perform these services at Hazardous, Toxic, and Radioactive Waste sites funded through the Department of Defense Installation Restoration Program or the Defense Logistics Agency at Shaw AFB. The base period for the SATOC will be seven years, with a total contract ceiling of $40,000,000. The pricing structure will be firm-fixed-price. A site visit is scheduled for March 5, 2026; attendee lists are due no later than February 23, 2025. There is no solicitation at this time. https://sam.gov/workspace/contract/opp/ee08eada59df46efac16bfc794141226/view

NAVAJO AREA - ABANDONED MINES RESPONSE AND CONSTRUCTION SERVICES (SNOTE) [Market/Commercialization]

Mon, 23 Feb 2026 14:35:22 GMT

U.S. Environmental Protection Agency, Region 9 Contracting Office, San Francisco, CA
Contract Opportunities on SAM.gov 68HE0926R0006, 2026

This is a special notice under NAICS code 562910. EPA requires a contractor to provide cleanup, response, and construction services, primarily at former uranium mining-related sites located within or near the Navajo Nation and the Grants Mining District in New Mexico in U.S. EPA Regions 6 and 9. The U.S. EPA expects to make an award for this requirement by September 1, 2026. A pre-proposal Industry Day/Conference amongst the U.S. EPA and Potential Offerors is anticipated to occur approximately one week after the Request For Proposals Solicitation is posted on FEDCONNECT and SAM.gov.
https://sam.gov/workspace/contract/opp/5c44292dbf1d4217951d5659bc2cd9f4/view

INDEFINITE DELIVERY/ INDEFINITE QUANTITY (IDIQ) CONTRACT FOR ENVIRONMENTAL SAMPLING SERVICES [Market/Commercialization]

Mon, 23 Feb 2026 14:35:08 GMT

Naval Facilities Engineering Command, NAVFAC Mid-Atlantic
Contract Opportunities on SAM.gov N4008526R0010, 2026

This Indefinite Delivery/ Indefinite Quantity (IDIQ) contract with recurring and non-recurring Environmental Sampling Services will be issed under NAICS code 541380 at the Naval Weapons Station Crane, Crane, IN and Lake Glendora Test Facility, Sullivan, Indiana. The contractor shall have the ability to provide environmental sampling services including building and equipment surveys, consultation and program management support related to asbestos, lead, PCBs, soil and water, environmental condition of property assessments, and testing and laboratory analysis services. Additional services required include library, database file, and program support related to these environmental programs. This acquisition will result in the award of a contract for a term of one 12-month base period and four 12-month option periods. The term of the contract will not exceed 60 months or the total value of the contract, whichever comes first. The options may be exercised within the time frame specified in the resultant contract at the sole discretion of the Government subject to workload and/or satisfaction of the contractor?s performance under this contract. https://sam.gov/workspace/contract/opp/c400de0d9d16442c9ea370ef084f6a56/view

ENVIRONMENTAL SECURITY TECHNOLOGY CERTIFICATION PROGRAM (ESTCP) - INSTALLATION ENERGY AND WATER TECHNOLOGIES (EW) SUPPLEMENTAL (PRESOL) [Market/Commercialization]

Mon, 23 Feb 2026 14:34:34 GMT

U.S. Army Corps of Engineers, Humphreys Engineer Center Support Activity, Alexandria, VA
Contract Opportunities on SAM.gov W912HQ26S0030, 2026

This is a pre-solicitation notice for planning and informational purposes only. The Environmental Security Technology Certification Program (ESTCP), in coordination with the U.S. Army Corps of Engineers, seeks pre-proposals from qualified private sector organizations under a Broad Agency Announcement for Fiscal Year 2027 to demonstrate and validate innovative, cost-effective Installation Energy and Water technologies that enhance DoD installation resilience, energy security, water efficiency, and infrastructure sustainment. ESTCP is soliciting mature, non commercial technologies that have completed proof-of-concept and are ready for operational demonstration at DoD facilities to generate defensible cost and performance data, support regulatory and end-user acceptance, and accelerate technology transition and implementation across DoD. Selected projects will involve structured demonstrations under real-world conditions, development of guidance and reporting deliverables, engagement with DoD users and regulators, and participation in a multi-stage competitive evaluation process beginning with a mandatory pre-proposal submission. To be eligible for consideration, parties wishing to respond to this announcement must submit a pre proposal in accordance with the instructions on the website, no later than 2:00 PM EDT on March 26, 2026. https://sam.gov/workspace/contract/opp/6cc929c109174254b8fbd1a72d736267/view