Joan the Utility Solid Waste Activities Group (USWAG) at its 9th Annual Coal Combustion Residuals (CCR) Workshop, April 17-19, at the New Orleans Marriott.
The CCR Workshop is designed to provide attendees with an understanding of the CCR Rule, a key regulatory compliance.
Abstract: CCR groundwater monitoring programs require routine detection monitoring around regulated units. The purpose of routine detection monitoring is to identify situations where groundwater quality could be impacted by contaminants mobilized from CCR. Background data are collected to characterize the statistical distributions of groundwater quality parameters in the aquifer where there is no potential impact from regulated units. During operational, closure, and post-closure care activities the same groundwater quality parameters are sampled periodically downgradient from the regulated unit and compared to these background data. Any statistically significant increases over background are investigated as a potential result of CCR leachate impacting groundwater quality.
The procedure for design and implementation of a groundwater monitoring plan foresees that all routine detection monitoring program will generate false positive results, and the EPA Unified Guidance recommends that the monitoring plan be designed to minimize the site-wide false positive rate. For CCR monitoring programs, the number of well/parameter pairs and sampling frequencies are fixed by site-specific and regulatory requirements. This leaves the CCR permittee with two focus areas to minimize the site-wide false positive rate. The first is a robust characterization of background that captures both the spatial and temporal variability at the site. The second is a complete characterization of leachate composition, including unregulated constituents, and the incorporation of correlation into the statistical comparison to background. These two focus areas can be used to minimize costly assessment and corrective action activities.
Top 3 things audience will learn:
1) Routine groundwater detection monitoring will generate false positive results.
2) There are two areas that a CCR groundwater monitoring program should focus on to minimize false positives: (1) robust characterization of background; and (2) robust characterization of leachate composition
3) Building a CCR groundwater monitoring program upon these two focus areas will ultimately help reduce costly assessment and corrective action activities resulting from false positives.
In 2014, the Environmental Protection Agency (EPA) finalized regulations addressing the disposal of coal combustion residuals (CCR) generated by electric utilities and independent power producers. The rule regulates CCR as non hazardous waste under the Resource Conservation and Recovery Act (RCRA) and establishes national minimum criteria for existing and new CCR landfills and surface impoundments, including location restrictions, design and operating criteria, groundwater monitoring and corrective action, closure and post closure care, and recordkeeping, notification and internet posting requirements. Because the rule is self implementing, it is critical that owners and operators of CCR management units and engineering consulting firms possess a thorough understanding of the rule in order to ensure consistent compliance with these new federal standards.