Abstract

This article compares and contrasts the requirements presented in the Resource Conservation and Recovery Act (RCRA) as modified by the Hazardous and Solid Waste Amendments (HSWA) (U.S. House of Representatives, 1983) and found in Title 40, Code of Federal Regulations (CFR), Parts 264 (Permitted facilities) and 265 (RCRA Interim Status facilities), Subparts F (40 CFR 264F and 265F) (December, 1991), and to provide some insight into the rationale the U.S. Environmental Protection Agency (EPA) used during the compilation and modification of those regulations. Activities associated with the direct exploration, development, and production of oil and natural gas are excluded from groundwater monitoring requirements under RCRA. However, many activities associated with the refining and subsequent use of oil and natural gas are not exempt.

Originally, EPA intended 40 CFR 264 Subpart F (264) to build on a foundation established by compliance with 40 CFR 265 Subpart F (265) (December, 1991). Part 265 is designed to detect potential impacts on groundwater quality from Treatment, Storage, and Disposal Facility (TSDF) operations and to characterize identified impacts to groundwater quality. Part 264 is designed to detect specific types of groundwater contamination, to monitor compliance with a set standard of concentration limits unique to each TSDF, and to monitor the effectiveness of implemented corrective actions.

The major differences in groundwater monitoring between Parts 265 and 264 are the types of TSDFs impacted and the monitoring parameters prescribed. The exemptions allowed under Part 265 do not apply to Part 264. This creates the potential for a TSDF to perform Part 264 groundwater monitoring without ever having performed monitoring under Part 265. Because of the non-site specific nature of the Part 265 monitoring parameters, natural or seasonal variations in groundwater quality can cause true contamination to go undetected. Part 264 monitoring parameters have a much higher resistance to such influences. Sampling protocol, reporting requirements, concentration limits, and statistical analyses are generally similar for both Parts 264 and 265.