Former Montana, California mines designated Superfund sites

Former Montana, California mines designated Superfund sites
The U.S. EPS has proposed to add Northern and Central California abandoned minesites, along with an Anaconda Copper smelter and refinery in Montana to Superfund's National Priorities List.
Author: Dorothy Kosich
Posted:  Wednesday , 09 Mar 2011 
The U.S. EPA announced Tuesday that it is adding three former minesites to the Superfund site list.
The EPA and the Montana Department of Environmental Quality (MDEQ) agreed to add the Anaconda Copper Mining Co. Smelter and Refinery (AMC) in Cascade County, Montana, to the National Priorities List of Superfund sites.
The ACM site contains contamination from historic smelting and refining activities at the Anaconda Great Falls Reduction Department. Over the years wastes at the ACM site were placed in an onsite-landfill or dumped directly into the Missouri River. Meanwhile, the smelter operations used a 506-foot-tall plant stack for several years before pollution control technology became common.
"This stack allowed contaminants to be aerially dispersed over a wide area in the vicinity of the facility," said EPA. The agency's primary concern is recent sampling results which show elevated levels of arsenic, lead and cadmium in residential soils. Past analyses documented the presence of metals in the Missouri River sediments, and along the railroad bed, antimony, arsenic, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, silver, sodium and zinc.
The five areas being considered for investigation and potential cleanup include: residential soils; the former smelter site; areas along the railroad bed; Missouri River sediments and surface water; and groundwater.
"The listing of this site enables all agencies involved to identify and clean up contaminated areas in conjunction with ongoing local public projects," said Julie DalSoglio, EPA Montana Office director.
The EPA is also proposing to add two abandoned California mines to the Superfund National Priorities List.
Located in San Benito County, the New Idria Mercury Mine site affects waterways leading to the San Joaquin River and San Francisco Bay. The Blue Ledge Mine in Siskiyou County discharges into streams in the Rogue River-Siskiyou National Forest and ultimately the Applegate Reservoir, a popular recreation area.
"Abandoned mines have left behind a toxic legacy that continues to threaten the health of people and natural resources of California," said Jane Diamond, director of the EPA's regional Superfund program. "Listing these two sites will enable the EPA to reduce risks to the environment and ensure protection of important water resources."
New Idria is located southeast of Hollister. Past mining operations have resulted in mercury contamination and acid mine drainage in the San Carlos Creek, Silver Creek, and a portion of Panoche Creek. Environmental impacts extend more than 15 miles to creeks and wetlands areas, endangered species habitat, and ultimately the San Joaquin River and the San Francisco Bay.
The Blue Ledge Mine is located on privately owned land surrounded by the Rogue River-Siskiyou National Forest, south of the Oregon-California border. "Copper, cadmium, other metals, and acid mine drainage from past copper and zinc mining operations have contaminated sediments and surface water at levels that are toxic to aquatic organisms," EPA noted. "Impacts include the absence of fish for more than three miles downstream and potential negative impacts to fisheries all the way to the Applegate Reservoir, nearly eight miles downstream."
In 2010, the U.S. Forest Service received $12.4 million in American Reinvestment and Recovery Act funds, along with $1.4 million from the ASARCO Environmental Trust to place the waste rock from Blue Ledge into an on-site repository. The work began last year.