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Groundwater Cleanup Program Progress Summary. San Francisco Bay Regional Water Quality Control Board – April 2002. Overview.
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Groundwater Cleanup Program Progress Summary San Francisco Bay Regional Water Quality Control Board – April 2002
Overview We have made significant progress in groundwater cleanup since we initiated investigations in early 1980. Our program focuses on high-risk groundwater resources and significant chemical releases. We have also made good progress on closing lower risk cases. This summary highlights six areas: • Background • Cleanup Standards and Technologies • Fuel UST Program • Non-Fuel Program (SLIC) • Special Features • What is Next?
Background: Budget Groundwater programs are a major focus of the Board’s program, comprising a third of our annual budget • Over $4 million per year directed toward groundwater and soil pollution issues • 45 Board staff directly involved
Background: Caseload 8,558 1,665 • This is the universe of contamination sites in our region • Fuel UST cases are the most numerous but most are closed or overseen by local agencies • Non-fuel cases involve releases of solvents and other contaminants • Above ground tank (AGT) cases include refineries and terminals • We focus on containment at landfills, versus cleanup at other sites • Federal facilities (DOD/DOE) are few in number but require lots of oversight due to their size and complex environmental problems
Background: Contaminant Types The Regional Board oversees cases with a wide variety of contaminant types in soil, groundwater, and sediments • Petroleum products - gasoline, diesel, and gasoline oxygenates such as MTBE • Solvents - both chlorinated and non-chlorinated • Inorganics - mainly metals such as arsenic, chromium, and lead • Persistent organics - including PCBs and pesticides
Our Cleanup Standards • Original goal: cleanup to background • Reality check: this is not technically or financially feasible in most instances, either technically or based on 15 years of cleanup experience • Typical standards (per law, Basin Plan, policy): • Groundwater (drinking water source): MCLs • Groundwater (non-drinking water): risk-based * • Soils : Basin Plan and risk-based * • State Board resolution 92-49 has some additional options * Set to protect human health and ecological receptors (e.g. avoid impacts in indoor air or nearby creeks)
Cleanup:Soil Vapor Extraction Polluted soil
Discharge to storm drain or sanitary sewer Treatment unit Groundwater table Extraction well Cleanup:Pump and Treat
Cleanup:Air Sparging Polluted groundwater
Cleanup:Enhanced Bioremediation Polluted
Cleanup Costs • Cleanup costs to date exceed $500 million for sites overseen by the Regional Board • Dischargers at 20 “Superfund” sites have spent about $270 million on cleanup • Dischargers at other non-fuel sites in this region have spent an undetermined amount on cleanup activities • The state’s fuel tank cleanup fund has reimbursed about $250 million for cleanup at fuel tank sites in this region ?
Fuel UST Program:Remediation • About 65% of the roughly 9,000 fuel UST sites have completed source control • About 7% of the sites have active groundwater cleanup in progress • Less than 1% have other engineering controls including capping and containment barriers • Source: Geotracker database (includes open and closed cases)
Fuel UST Program:Case Closures Current Case Status Open Closed • Together with local agencies we are steadily closing cases; about 70% are now closed • Source: LUSTIS and Geotracker databases
Fuel UST Program:MTBE • MTBE is a widely-used fuel oxygenate • Major use began in early 1990s • Phase-out planned for 12/02 but delayed until 1/04 • MTBE poses a threat to groundwater • About 91% of open groundwater cases have tested for MTBE • Of these cases, 89% have detected MTBE • Three municipal supply and several private wells impacted • We have taken pro-active steps to address threat • Budgeted additional resources for MTBE oversight and policy development • Used GIS extensively to identify high-priority MTBE release sites • Required rapid investigation and remediation at those sites • Initiated pilot program to require groundwater monitoring at key operating service stations which may have unreported releases
Fuel UST Program:MTBE (con.) • About 500 high-priority MTBE sites in region • 133 class A and 290 class B sites • Most overseen by local agencies • Many sites in Santa Clara Valley • Significant threat from operating stations • Pilot study in Santa Clara Valley found new releases at 70% of upgraded USTs • Need for periodic groundwater monitoring at high-threat operating stations, to augment leak detection Key: Blue – supply well Red – class A MTBE site Yellow – class B MTBE site
Non-Fuel Program: Remediation • About 60% of the roughly 700 non-fuel sites we oversee have undertaken source control measures, such as soil excavation, soil vapor extraction, and free product removal (includes active plus closed cases) • About 28% have conducted active groundwater cleanup, such as “pump and treat”, sparging, enhanced biodegradation, and innovative methods • A relatively few sites have implemented other remedial actions, including monitored natural attenuation (MNA), engineering controls (such as capping and containment barriers), and institutional controls (such as deed restrictions and construction health & safety plans) Source: SMS database and RB staff survey Source control Groundwater cleanup Eng. Controls Inst. Controls MNA
418 Closed 1,247 Open Non-Fuel Program:Case Closures • About 25% of the roughly 1,600 non-fuel cases we oversee are closed • Non-fuel cases are generally harder to close than fuel UST cases for several reasons: • Non-fuel pollutants are harder to clean up • No state fund to reimburse dischargers for cleanup costs • More limited staff resources to oversee non-fuel sites
The Regional Board is lead on 21 Federal Superfund sites under agreement with USEPA These sites pose the highest risk to currently used groundwater resources in Silicon Valley Final remedial programs are ongoing at all 21 sites Cleanup activities at these sites has removed over 670,000 pounds of pollutants, primarily VOCs We estimate that this amount would double if mass-removal data for all non-fuel sites were included Non-Fuel Program:Superfund Remediation
Non-Fuel Program:Superfund Land Use • At nearly all the Superfund sites we oversee, site investigation and cleanup have proceeded without significantly impacting site use or redevelopment • We suspect that results are similar for other non-fuel sites we oversee Percentage of Sites
Non-Fuel Program:Enforceable Board Orders • Sites with significant threats to human health and the environment have “Site Cleanup Requirements” Other lower threat sites are under staff “letter orders” • Site Cleanup Requirements are enforceable orders adopted by the Regional Board in a public meeting • Site Cleanup Requirements establish a site-specific program for investigation and remediation • Virtually all Site Cleanup Requirements set drinking water standards as the cleanup goal for groundwater
Non-Fuel Program:Cost Recovery • Our goal is for all non-fuel dischargers to reimburse staff for our oversight costs • Since the early 1990s, we have steadily increased in the number of non-fuel sites enrolled in our cost recovery program • This funding mechanism facilitates focused oversight of cases • Currently, about 77% of active non-fuel cases are on cost recovery
Groundwater Basins Groundwater Protection and Focused Cleanup Plans Groundwater Protection Beneficial Use Study Special Features: Resource Focus Napa Valley • The Department of Water Resources identifies 32 groundwater basins in the Region • Areas of significant municipal use (Santa Clara Valley and Niles Cone) receive high priority from staff for cleanup plans • Staff have also worked on basin protection efforts in Napa Valley, Westside Basin, and Livermore Valley groundwater basins • Regionwide, there have been limited impacts to municipal water supply wells Livermore Valley Westside Basin Niles Cone Santa Clara Valley
Special Features: Enforcement • While most dischargers voluntarily comply with cleanup requirements, a few have refused or been slow to complete necessary work • The Board has taken formal enforcement against 33 “cleanup” dischargers since the mid 1980s, imposing administrative civil liability of about $2 million • Some of this liability has been suspended following completion of required tasks or supplemental environmental projects
Special Features: EncouragingInnovative Technologies Enhanced Bio-Remediation • Oxygen or nutrients are injected into the contaminated groundwater to promote biological treatment • In-situ method that’s most effective in source areas • Proven for fuel cleanups and becoming more prevalent for solvent cleanups Permeable Barriers • Passive, in-situ technology using a catalyst (e.g. iron) to convert solvents to non-toxic components (e.g. chloride) • Greatly reduces long-term operation and maintenance costs over active pump and treat systems Rapid Oxidation • Hydrogen peroxide, potassium permanganate, or other oxidizing solutions are injected into into the contaminated groundwater to destroy volatile organic compounds • Effective in source areas, less effective for diffuse contaminant plumes • Treats groundwater without the need to pump it to the surface and discharge it
Special Features:Regulatory Innovations Risk-Based Cleanups Risk Management • Use risk assessment to determine threat to human health and water quality • Developed risk-based screening levels (RBSLs) to speed up regulatory process • Use mix of cleanup and risk management to address contamination • “Containment zones” at three sites • Require deed restrictions at sites with significant contamination (40 so far) • Maintain site cleanup requirements at sites where complex risk management needed (e.g. cap maintenance) • Working with cities and counties to establish local permitting as a primary enforcement tool “Brownfields” Cleanup and Redevelopment • We have focused on several areas – Emeryville, East Palo Alto, Oakland, and SF • Region-wide efforts include negotiating 10 “prospective purchaser” agreements and issuing more than 200 “comfort” letters to buyers and neighboring properties • Our efforts have led to cleanup and redevelopment of more than 50 “brownfields” sites, including Mission Bay, Eastshore Park, and the former Pacific Refining site
What Is Next? Monitored Natural Attenuation • Natural attenuation has been documented at fuel UST sites • We see evidence of natural attenuation at some non-fuel sites but this still requires site-by-site documentation and follow-up monitoring Risk-Based Decision Making • We will continue to apply risk-based decision making on a site-specific basis • We will make more use of long-term risk management measures on a site-specific basis Basin Planning • We will complete comprehensive evaluations of groundwater beneficial uses to ensure protection of groundwater resources and to facilitate development of reasonable groundwater cleanup standards