Greg Reller Thank you EPA staff for inviting me. Many co-workers who have taught me. Clients who have provided the opportunity to work on these challenges. Burleson consulting for supporting my efforts to participate. Introduction Questions Examples Discussion Focus of this presentation is measurement of CERCLA cleanup effectiveness through monitoring. Many cleanups are at abandoned mines that affect downstream reservoirs. Response is intended to reduce mercury entering the system. Requirements driving many responses are based on mercury in fish tissue Mercury Mines Primary Sources: Waste Rock, Overburden, Tailings (Calcines), Drainage Mercury Mine Pathways: Vapor, Dust, Surface Water, Groundwater. Mercury Mine Secondary Sources: Sediment, Surface Water. Gold Mines Primary Sources: Soil and Sediment at Stamp Mills, Sluices, Tailings. Gold Mine Pathways: Vapor, Dust, Surface water, Groundwater. Gold Mine Secondary Sources : Debris, Dredge Tailings, Sediment. Identify Mercury Source Mercury Source Control Improvement Other mercury sources include: Atmospheric Deposition. Ambient Soil : Mean 0.26 mg/kg, max 1.1mg/kg (Kearney Report 1996). Sediment: up to 0.4 mg/kg (various regional monitoring studies, USGS, RWQCB). Mercury in Fish Atmospheric Deposition Sediment Flux Wetlands Stratification Nutrients and Biological Activity Stage Fluctuations What do we measure to evaluate cleanup effectiveness? Concentration of mercury in sediment/water/biota/air?, Mass of mercury in sediment/water/air? Are there pre-response data available for comparison with post-response data? Are we measuring something related to the mine site? Sulphur Bank Mercury Mine 1979 Earth and Rock Dam 1992 Waste Rock Dam graded and covered 1999 Stormwater controls implemented 0.3 mg/kg OEHHA Screening Value 0.09 mg/kg RWQCB Trophic Level 3 Screening Value 0.19 mg/kg RWQCB Trophic Level 4 Screening Value Sulphur Bank Mercury Mine: Oaks Arm of Clear Lake Total Mercury (mg/kg wet weight) in Large Mouth Bass Sulphur Bank Mercury Mine: Oaks Arm of Clear Lake Total Mercury (mg/kg wet weight) in Young of Year Juvenile Large Mouth Bass (2005 to 2007) SBMM Lake Sediment Pilot Capping Coastal California Mercury Mine Mill Site Tailings: Site remediation under order from the California Regional Water Quality Control Board with pre- and post- remediation monitoring. Source Control: Plug adit, remove tailings with high concentrations of total mercury surface water diversion, stabilization, and revegetation. Coastal California Mercury Mine: Rainfall, Sediment Total Mercury (dry weight), and Total Mercury (mg/kg wet weight) in Large Mouth Bass Mercury in Fish Atmospheric Deposition Sediment Flux Wetlands Stratification Nutrients and Biological Activity Stage Fluctuations Discussion/Questions Greg Reller (916) , extension 11
