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Arsenic
Chromium VI Dense Nonaqueous Phase Liquids (DNAPLs) 1,4-Dioxane Dioxins Mercury MTBE Perchlorate POPs PCBs TCE Other Contaminants
Detection and Site Characterization The purpose of this section is to identify online analytical methods that can be used for detecting, measuring, and/or monitoring chromium. The intent is not to provide an exhaustive list, but to identify well-established methods that are used as standards for analysis, particularly those used for environmental samples and approved by EPA and the National Institute for Occupational Safety and Health (NIOSH).More innovative methods are also included if their components are commercially available.
Adding Method 6800 to the Hexavalent Chromium Analysis Toolbox Brief explanation of using SW-846 Method 6800 (Elemental and Speciated Isotope Dilution Mass Spectrometry) for analyzing hexavalent chromium in difficult matrices.
The OSHA Ceiling Standard is found in 29 CFR 1910. 1000 Table Z-2, for chromic acid and chromate. The ACGIH Standard is more complex; based upon epidemiological studies, it considers chromates confirmed human carcinogens. Two analytical methods commonly used when quantifying chromate exposures are 1) a general metals screen, NIOSH Method 7300 and 2) a specific analysis for hexavalent chromium, NIOSH Method 7600. There are three different calculations depending upon the analytical method used.
A field study was conducted to compare the performance of two laboratory-based procedures (OSHA Method ID-215 and NIOSH Method 7605) and a field-portable method (NIOSH Method 7703). Based on analysis of variance (ANOVA) results, no statistically significant differences were observed between mean values measured using each of the three methods. Small but statistically significant differences were noted between results obtained from performance evaluation samples for the NIOSH field method and the OSHA laboratory method.
Environmental Forensics: Contaminant-Specific Guide Environmental forensics is the application of scientific techniques for the purpose of identifying the source and age of a contaminant. This book discusses the following contaminants and contaminant groups: mercury, asbestos, lead, chromium, methane, radioactive compounds, pesticides, perchlorate, polychlorinated biphenyls, arsenic, chlorinated solvents, polyaromatic hydrocarbons, crude oil, gasoline, microbes, and compounds found in sewage.
Using the demonstration-derived precision RSD results and the coefficient of determination as the primary qualifiers to screen a suite of metals, the XL Spectrum Analyzer produced data of qualitative screening level for total chromium. Since a precision RSD value was not determined for chromium, no data quality level can be assigned.
Using the demonstration-derived precision RSD results and the coefficient of determination as the primary qualifiers to screen a suite of metals, the TN 9000 produced data of qualitative screening level for total chromium. In the operation of these instruments, the user must be aware that FPXRF analyzers do not respond well to chromium and that detection limits may be 5 to 10 times greater than conventional laboratory methods.
This report describes the cost and performance of X-Ray Fluorescence and Fiber Optic - Laser-Induced Breakdown Spectroscopy probes that can be driven into the subsurface by a cone penetrometer rig or direct push rig. The instruments detect a number of heavy metals including total chromium. European Virtual Institute for Speciation Analysis (EVISA) Offers wide ranging information on chemical speciation issues including analytical methods and has 113 specific links for chromium.
The Industrial Hygiene Branch, in a collaborative effort with the National Institute for Occupational Safety and Health (NIOSH), developed a field analytical method to measure hexavalent chromium (Cr(VI), chromate) levels in air. The method uses ultrasonic extraction of sampling filters, solid-phase extraction of chromates from the extracted solution, and a determination of chromate concentrations by spectrophotometry. It is an alternative to NIOSH methods 7300 and 7600 and overcomes some of the disadvantages of these methods. The chromate field method is relatively easy to use, specific for CrVI, has a lower detection limit than NIOSH 7600, and allows analysis before there is a chance for significant sample degradation. Mass Flux Toolkit to Evaluate Groundwater Impacts, Attenuation, and Remediation Alternatives To help site managers and site consultants estimate mass flux and understand the uncertainty in those estimates, ESTCP has funded the development of a computerized Mass Flux Toolkit, free software that gives site personnel the capability to compare different mass flux approaches, calculate mass flux from transect data, and apply mass flux to manage ground-water plumes. The toolkit spreadsheet and associated documentation are available on the ESTCP contractor's website in a zipped file.
This presentation discusses joint efforts on the part of several state and federal agencies to produce a speciated Standard Reference Material from a natural source for chromium.
Method 7024: Chromium and Compounds, as Cr
Although the reviewers identified no fully developed methods in current use for vadose zone chromate characterization, the following technologies were recommended for additional evaluation and testing: laser-induced breakdown spectroscopy, Raman spectroscopy, laser-induced fluorescence, x-ray fluorescence, in situ specific conductance, high-resolution resistivity, partitioning tracers, and neutron moisture logging.
The authors propose a method for simultaneous measurement of local groundwater-specific discharge and Cr(VI) mass flux using a permeable adsorbent device. Test Methods for Evaluating Solid Wastes: Physical/Chemical Methods, 3rd Edition
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