John Gioia

Chair, Board of Supervisors , Contra Costa Public Works

Mr. Chairman, and members of the Committee, thank you for the opportunity to appear before you today to discuss an issue of great importance for the water quality of our County, the State of California, and other States of the Union - the cleanup of abandoned or inactive mines. I appear before you as Chair of the Board of Supervisors of Contra Costa County and the Contra Costa County Flood Control and Water Conservation District. I am pleased to provide you with our experiences and recommendations related to abandoned mine cleanups and the liability associated with a county agency involved in the clean up work.


I would like to describe to the Committee an example of a project in Contra Costa County that would greatly benefit water quality in the region, yet has not been able to be completed due to the lack of “Good Samaritan” legislation.


Contra Costa County is located in the San Francisco Bay Area of California. The west portion of the County fronts on the Bay, while the northern portion fronts along the Sacramento River, and the east portion drains into the Sacramento-San Joaquin Delta. Mount Diablo, the most prominent and tallest mountain in the area, presides in the center of the County. Marsh Creek drains from its headwaters at the top of Mt. Diablo to the west towards the Delta and discharges into the Sacramento River. An abandoned mercury mine is located in the upper slopes of Mt. Diablo, near the headwaters of Marsh Creek. Rain water washing over the mine tailings transports mercury down into Marsh Creek and ultimately out into the San Francisco Bay. Marsh Creek also flows through the communities of Brentwood and Oakley with a total population of 60,000 residents.

In the early 1960’s, our Flood Control District built flood protection improvements in the Marsh Creek watershed, channelizing the downstream reaches of Marsh Creek through the flat alluvial area near the City’s of Brentwood and Oakley.

In 1963 the Flood Control District built a dam across Marsh Creek approximately five miles upstream of the City of Brentwood for flood control purposes. The resulting Marsh Creek Reservoir impounds water year round, and has extensive riparian, marsh and aquatic growth along the shoreline, providing habitat for a variety of wild life including resident populations of fish. The Flood Control District owns the Marsh Creek Reservoir and most of the downstream channel.

Health Issue

In 1980 the California Department of Fish and Game analyzed fish from the reservoir and found mercury levels in the fish flesh were above existing health standards. The reservoir has since been fenced off and noticed for no trespassing or fishing due to the mercury contamination. Mercury is a health problem in the San Francisco Bay Area and advisory notices are posted for adults to not eat fish from the Bay more than twice every month (only once a month for children and pregnant women) due to elevated levels of mercury in the flesh of the fish.

The Mercury Mine

Mercury was first mined in this area in 1875 and continued on and off until 1971. In 1974, the current property owner purchased the abandoned mine and surrounding property. The property totaled 109 acres and is bordered on three sides by Mount Diablo State Park. The current owners were not looking to develop the property, but looked at the property as a beautiful spot to raise their children and retire. The owner and his wife intended to build their retirement home on the property, they had no plans nor any desire to mine the property, or contract with others to mine the property.

The State’s Regional Water Quality Control Board (RWQCB) first issued waste discharge requirements (WDR) to prior mine operators in 1952 and recommended corrective action be taken. Although waste discharge requirements were issued to the mine operators, contaminated discharges continued after the mine was abandoned. In 1978 the RWQCB issued the property owner a Cleanup and Abatement Order because of mercury discharging from the mine site, even though the property owner was not a mining operator and did not create the problem. In response, the property owner has taken efforts to clean up the property as best he can, but does not have the resources to complete a full scale mine remediation project. The property owner recently said, “So far we have spent over $300,000 of our retirement money, in 1975 dollars, and the “well” is nearly dry.”

Attempted Remediation

In 1995 Contra Costa County contracted with a team from the University of California at Davis, lead by Dr. Darryl G. Slotten, to study and provide an assessment of mercury in the Marsh Creek watershed. The study showed that approximately 90% of the mercury in the watershed originates from the piles of tailings at the abandoned mercury mine. Based on the study, Contra Costa County applied for a Calfed grant in 1997 to remediate the mercury mine and reduce the mercury transported from the mine to the downstream watershed and into the Bay/Delta system. Our County Counsel and Risk Manager reviewed the grant in light of the lawsuit that the East Bay Municipal Utility District was facing with the remediation work they had done at the Penn Mine site and concluded that our county would be exposed to liability if the project was built. As a result, we withdrew the grant. Our sentiment was summed up in a staff memo that said, “It is sad that we can’t try to help this problem, but we cannot risk getting into a situation that costs the County $5 million dollars plus huge attorney bills like it did the East Bay Municipal Utility District”.

The Flood Control District is still interested in remediating the mine and we are confident we can get the grant funds to do so. The local watershed council in the Marsh Creek watershed is a stakeholder group that includes several local environmental groups and is very supportive of our efforts to remediate the mine. The property owner is also very supportive of our efforts. The barrier to us implementing the project is liability.

Good Samaritan Initiative

Understanding that liability exposure was the fundamental issue preventing us from participating in remediating the mine, Contra Costa County partnered with the Natural Heritage Institute and the cities of Oakley and Brentwood for a grant in 2000 that sought to solve the liability problem. This grant application was unsuccessful. Still interested in pursuing the remediation of the mercury mine, last year we partnered with Sustainable Conservation, a non-profit organization with experience in the arena of liability exposure with environmental projects. This has lead to discussions with EPA on their Good Samaritan Initiative and the prospect of emulating the Trout Unlimited cleanup project in the American Fork River watershed in Utah.

The Good Samaritan Initiative is based on EPA’s administrative authority to issue an Administrative Order and Consent. This is intended to be used in enforcement actions for liable parties. The difference is we are not a liable party. We are interested and willing to help clean up the mine site, but we don’t legally have to. Since the Administrative Order and Consent is an enforcement tool, it would take an inordinate amount of our staff time and resources to modify it to be used for voluntary work. The other concern we have is that throughout the negotiation process to draft the Administrative Order and Consent there is no public input. In our experience, projects that have no public input end up creating huge problems later on. When the public ultimately finds out about the project, we have to spend an inordinate amount of staff time and resources to change the project design based upon subsequent public input. As a result, we will not sponsor a project development process without public input.

We support legislation specifically tailored to agencies cleaning up mines on a voluntary basis. This would be much better than the current attempt to modify an existing enforcement tool to achieve the same purpose.

Liability Issue

Our liability exposure occurs in at least two ways. One is under the Clean Water Act. This would be similar to the situation the East Bay Municipal Utility District (EBMUD) found themselves in after working on improving the Penn Mine drainage. EBMUD worked with the State’s Regional Water Quality Control Board (RWQCB) in developing a remediation plan for the mine site. The remediation work, which was completed in 1978, reduced the pre-project copper discharge from an average of 64,000 pounds per year to an average of 13 pounds per year. An environmental group sued claiming that EBMUD should have taken out a National Pollutant Discharge Elimination System (NPDES) permit. The courts agreed and found that in performing the remediation work EBMUD should have obtained a NPDES permit, then followed the NPDES requirements to improve the discharge to current water quality standards. After the court case, EBMUD and the RWQCB worked on a follow-up remediation plan that brought the site back to pre-mining conditions at a cost of approximately $10,000,000.

There is also liability exposure to the County under the Federal Comprehensive Environmental Response, Compensation and Liability Act (CERCLA). This law imposes liability for response costs upon owners and operators for the release of hazardous materials from a facility.


California’s State Water Resources Control Board has identified the entire length of Marsh Creek, from the mine site to the Sacramento-San Joaquin Delta, as an impaired water body for mercury and heavy metals under Section 303(d) of the Clean Water Act. The San Francisco Bay Regional Water Quality Control Board is currently developing a total maximum daily load (TMDL) for mercury in the Bay Area. The TMDL will provide a long range plan and goals for reducing mercury in the watersheds that drain into San Francisco Bay. With the Mt. Diablo mercury mine being one of the important sources of mercury into the bay, it will be imperative to remediate the mine tailings and prevent further discharge of mercury from the abandoned mine site.

Contra Costa County and the Contra Costa County Flood Control and Water Conservation District have been interested in remediating the mercury mine in our county for the last fifteen years. We are confident that we will be able to obtain the grant funding necessary to remediate the mercury mine. Every granting entity we have talked to is extremely excited about the prospects of the Flood Control District remediating the mercury mine. We are ready, willing and able to fix a source of pollution in our county once the issue of liability exposure is addressed. We strongly support the efforts of EPA and Congress to adopt legislation that would eliminate our liability exposure and allow us to improve the water quality for the residents of Contra Costa County and downstream San Francisco Bay Area.