The following cleanups have been postponed due to potential NPDES liability.

Penn Mine Copper mine, Calaveras County

Because of a lawsuit in the 1990s, the Central Valley Board was compelled to do major remediation because the court found the Board was an NPDES discharger based on remedial work it did in the 1970s. Remediation is nearly complete, but the Board risks liability for residual seeps and other discharges.

Walker Mine Copper Mine, Plumas County

Regional Board spent over 30 years unsuccessfully suing the mine owner to cleanup acid mine drainage discharge that sterilized a creek. Finally, the Board plugged mine shaft and accepted settlement from mine owner’s estate. The Board remains liable for any point source discharge that may occur from the plug.

Buena Vista/Klau Mine Mercury Mine, San Luis Obispo County

Central Coast Board has unsuccessfully tried to secure cleanup from mine owner for over 20 years. These mines are the source of 80 percent of mercury pollution in Nacimiento Reservoir, which is under a fishing advisory. US EPA is willing to do cleanup on condition California takes over the long-term operation and maintenance. The state is unwilling to accept liability for NPDES discharges at site and so relieve the recalcitrant mine owner of responsibility. Cleanup may be delayed until potential state liability is resolved.

Mt. Diablo Mine Mercury Mine, Contra Costa County

Owner discovered mine after spending entire savings to buy land for a residence. Mine pollution has sterilized a creek and caused a fishing advisory in a nearby reservoir. With liability protection, a government agency could do partial remediation to significantly reduce pollutant discharges from the site. Without liability protection it is likely no remediation will occur.

In 1991, the Board secured $1 million from the State Cleanup Account to hire consultants to perform remedial work at those three mines. Although a responsible party eventually came forward to take remedial action, the Board decided to return the funds rather than apply them to mine cleanup because of liability concerns (brought on by the Penn Mine case.)

These mines discharge abandoned mine drainage to West Squaw Creek, a tributary to Shasta Lake. Impacts include elimination of aquatic life in the stream below the mines, frequent fish kills where the stream enters Shasta Lake and degradation of recreational/aesthetic uses in this part of the National Recreation Area. The owner, Alta Gold Company, has performed some remedial work but final site restoration is probably beyond their capability. There is a unique opportunity here for Alta Gold to sell the property to the public resource agencies for development of an off-road vehicle park with funds from the sale to be used for mine drainage control. This arrangement could provide substantial funds for problem solution but is presently not being actively pursued due to the liability issue.

This large abandoned copper mine discharges abandoned mine drainage to Little Backbone Creek and Shasta Lake. Impacts are similar to those previously described for the West Squaw Creek mines. The owner, Mining Remedial Recovery Company, has implemented a comprehensive mine sealing program but the results to date have been disappointing. Substantial modification of the sealing program or a new control strategy, such as collection and treatment, will be required to address the problem. The issue is further complicated by a lawsuit filed by the California Sport Fishing Protection Alliance. We believe that a cooperative effort at Mammoth Mine between the owners, resource protection groups, and the agencies would be more effective than lawsuits and enforcement orders.

this acid mine west of Redding discharges abandoned mine drainage to Willow Creek which is a tributary to the Wiskeytown Lake National Recreation Area. The discharge impacts aquatic life and recreational uses in the area. There is no responsible owner capable of implementing a control program. A reclamation feasibility study has been prepared by the Department of Water Resources (under contract to Regional Board), but no work has been done. Water quality and beneficial use improvements could be achieved through a combination of surface drainage control and mine sealing.

These two mercury mines would each benefit from actions to contain tailings and solid wastes and to divert surface waters. Staff estimates a cost of $1-2 million per mine.

Proposed actions at this mine include sealing the multiple portals, removing and covering the tailings pond, and rehabilitating the access road.

Bully Hill Mine, Shasta County

Staff proposes solid waste containment and portal scaling at this site.

S. 1787 would also support watershed cleanups. US EPA is working on regulations to permit publicly owned sewage treatment works (POTWS) to cleanup pollution within a watershed as an alternative to removing pollutants that exist at very low levels in the POTWS’ discharge. This will provide much greater removal of pollutants from watersheds and will help California comply with its mandate to implement Total Maximum Daily Load allocations. However, POTWS are not likely to cleanup abandoned mines under a watershed program unless they get some liability protection.

The St. Kevin Gulch project is located northwest of Leadville in the small perennial drainage known as St. Kevin Gulch. Mine drainage from the lower Griffin Tunnel flows as a series of springs from the waste rock pile approximately two miles above the confluence of St. Kevin Gulch and Tennessee Creek. The mine drainage has a pH of 2.6 to 2.9 and has rendered St. Kevin Gulch virtually devoid on any aquatic life below the drainage, and has an adverse effect on trout reproduction in Tennessee Creek. The mine drainage is to be treated using a combination of an anoxic limestone drain and a sulfate reducing bioreactor (wetland). An interceptor trench has been completed to help site the treatment system. The project is in the final design state. Commitments for materials, labor, services, and cash were obtained from local individuals, Lake County, and the USGS. These commitments have at least partially been withdrawn and the project postponed because of concerns about assumption of liability. The estimated construction cost is $122,300.

The McClelland Tunnel project is located along Interstate 70, one-half mile southeast of the town of Dumont. The McClelland Tunnel drains approximately 15 gallons per minute of metal laden water into Clear Creek. The site also contains mine and mill waste along Clear Creek , a county road, and a State Highway. The Colorado School of Mines, Department of Transportation, Department of Public Health and Environment, Clear Creek County, and Coors have been collaborating with DMG on this project. The DMG's part of the project is to construct a small sulfate reducing bioreactor and a small aerobic wetland to treat the mine drainage. Final designs for the water treatment aspects of the project have been prepared and are ready to be bid. The project portion has been halted because of the concern of the State for incurring perpetual liability for maintaining the treatment system. The estimated cost of this project is $26,800.

The Perigo project is located approximately 6 miles north of Central City in a small perennial steam known as Gamble Gulch. The Perigo mine drains a average of 70 gallons per minute of pH2.9-3.9 metal laden water. Gamble Gulch below the mine drainage is virtually devoid of aquatic life for six miles before its confluence with South Boulder Creek. In 1989 and 1990, a small project was completed in this drainage to remove mine waste rock and mill tailings from the steam bed in two locations and construct a test treatment system at the Perigo mine. The proposed treatment techniques for this site include an aqueous lime injection system, settling pond and sulfate reducing bioreactor, which will be capable of treating all the mine drainage. The design for the project is completed but will not be bid out for construction until additional baseline information of the watershed is collected. If liability issues are not resolved at that time, the project will not proceed. These estimated cost for this project is $114,640.

The Pennsylvania Mine project is located just east of Keystone ski area on Peru Creek. Acidic metal laden water drains from caved mine workings making the creek biologically dead. Though a 319 grant from EPA, DMG has installed an innovative hydro-powered water treatment mechanism and a settling pond. The drainage water is diverted form the mine adit into a hydropower turbine, thus generating the power to drive a feeder that doses limestone to buffer the water. Once in the pond metal precipitate can settle out, and the effluent progresses through three wetland cells. Here, sulfate reducing bacteria and low oxygen waters remove much of the remaining acid and metal. The project is 80% complete with only a redesigned feeder mechanism necessary. The project is on hold pending resolution of NPDES liability issues.

The Division of Minerals and Geology in conjunction with the Animas River Stakeholders Group has investigated hundreds of mine sites in the vicinity of Silverton. The resulting feasibility reports for Mineral Creek, Cement Creek, and the Animas River have identified at least two dozen sites having a significant impact on the Animas River water quality. Treatment recommendations have been made but project work can not proceed until the NPDES issue is resolved.

Montana

The State of Montana has inventoried its abandoned non-coal mine sites. Thus far, Montana has found 245 abandoned mines which have the potential to impact surface waters because they are within 100 feet of a stream. Of these, 71 sites have discharging adits (mine entrances emitting acid mine drainage into the environment). 89 of 245 sites are already known to be degrading water quality. These 89 sites have caused downstream water quality samples to exceed at least one Clean Water Act parameter–either the Maximum Contaminant Limits or Aquatic Life Standards.

Given recent developments in federal case law, Montana officials are gravely concerned that cleanup projects addressing abandoned mines which are known to be seriously degrading the state’s water quality will be halted due to Clean Water Act liability concerns.

Nevada

The Tybo Tailings Site is located in the Tybo mining district in Nye County, Nevada. It is approximately 58 miles east of Tonopah on U.S. Highway 6 and thence 6.5 miles northwest on the Central Nevada Test Sites Base Camp access road. The site is located in the Hot Creek hydrographic basin. Tybo Creek flows from Tybo Canyon in the Hot Creek Range and then easterly into the Hot Creek Valley. The tailings are the result of mining activity, which began around 1866. Silver, lead, zinc, copper, mercury, and small amounts of gold were recovered. By 1877, Tybo was the second largest lead producing area in the United States after Eureka, Nevada. Production continued on an intermittent basis until around 1940. Some very minor production occurred in the 1950’s and early 1960’s. Total recorded production from the district is valued at over $9 million.

The tailings impoundment is located just downstream from the mouth of Tybo Canyon. The actual impoundment is located in an ephemeral wash and is about 1,000 feet long and up to 600 feet wide (approximately 12 acres total). The dam has been breached, allowing tailings to migrate down the creek for at least 6 miles. The tailings appear to be about 20 feet thick at the dam. The tailings are highly acidic (surface water on the tailings has a pH of 1-3), have a strong sulfur smell, and are stained brown-orange to purple, red and black. Surface water has eroded channels into the tailings. All vegetation along the migration path from the impoundment is stressed or dead for at least 3 miles downstream.

Preliminary studies have detected arsenic and lead range up to 10,000 ppm, zinc up to 7,500 ppm, and copper up to 233 ppm. At this time, the State of Nevada has recommended evaluating groundwater use and the habitat of threatened and endangered species. Additional recommendations include measures to prevent wildlife from drinking surface water, and restricting site access by fencing and gating. NDOW has expressed concern about the effects on plants and wildlife and groundwater.

The Rip Van Winkle Mine site is located in the Merrimac mining district, Elko County, Nevada. The site is located at approximately 7,000 feet above mean sea level on Lone Mountain in the Independence Mountains, and is situated in the Maggie Creek Area hydrographic basin, which flows into the Humboldt River near Elko, Nevada. The Rip Van Winkle Mine recorded first production in 1918. It was the only active producer in the district after 1949 with limited production of lead, zinc and silver through 1966.

The mine site consists of shafts and underground workings, a mill, building foundations and several cabins, waste dumps and tailing impoundments. The tailings impoundments cover approximately 3 acres and contain acid-generating materials. Vegetation on the site is sparse and in the vicinity of the tailings, plants show signs of stress. Impacts to Humboldt River flows are unknown at present, but may be impacting endangered species.

The Norse-Windfall Mill Site is located 5 miles south of Eureka, Nevada. It is located in the Diamond Valley hydrographic basin in which perennial springs are prolific in the mountainous regions south of Eureka, with many flowing springs existing at the mill site. The Windfall Mine was discovered in 1908, and was operated intermittently for about 30 years as an underground operation with a cyanide vat leach facility. Around 1968, Idaho Mining Corp. acquired the property and mined the same ore body via open pit methods. Between 1975 and 1978 the Windfall Pit, and associated cyanide heap-leach piles, waste dumps, mill process building, office and laboratory were constructed. The last operator of the site was Norse Windfall Mines, Inc. The site has been abandoned since 1989 and little or no reclamation has occurred. In July 1994, the Nevada Division of Environmental Protection conducted a compliance inspection of the site and noted that unmaintained process components and materials left scattered about the property may have the potential to cause environmental damage by degrading the waters of the state.

Springs located within the site exceed the Nevada Water Quality Standards for arsenic, mercury, nickel, and cyanide. Within a 4-mile radius of the site, six municipal springs and one domestic well provide drinking water for Eureka. Water from the nearby springs are blended and pumped into 2 water tanks located just outside of Eureka. This water serves as the main water supply for the entire town.

South Dakota has been working on reclaiming two small hardrock mines that occur in the Black Hills with EPA and the federal agencies that administer the land upon which the mines are located. They are the Minnesota Ridge mine (Forest Service and private land) and the Belle Eldridge mine (BLM land).

South Dakota also recently completed an inventory of abandoned hardrock mines occurring in the Black Hills of western South Dakota in conjunction with the South Dakota School of Mines and Technology. Approximately 900 mines were identified in a four-county area (about 700 on private land and about 200 on federal land). The inventory purpose was primarily to identify abandoned mine locations, so little or no assessment work was completed for many of the mines identified. Many of these historic mines pose significant safety hazards, and some pose environmental problems, including impacts to water quality. The Good Samaritan bill would certainly be an incentive for getting some of these mines cleaned up.

Page last updated 06/27/2000