By Joel Warner
By Michael Roberts
By Joel Warner
By Michael Roberts
By Alan Prendergast
By Michael Roberts
By Michael Roberts
By Amber Taufen
Air Force Plant PJKS is located near Waterton Canyon on property owned by Lockheed Martin. It was built in 1956 to assemble and test missiles for the U.S. Department of Defense. Accidental spills and waste disposal left the soil and groundwater replete with rocket fuel, fuel oil and polychlorinated biphenyls, or PCBs. The site was placed on the NPL in November 1989. The Air Force, Lockheed Martin and the Army Corps of Engineers are working on the cleanup; the EPA estimates completion in 2005.
Broderick Wood Products treated utility poles, fences, railroad ties and other wood products with pentachlorophenol (PCP) on its Adams County property from 1947 to 1981. In 1983, the EPA found PCP -- which, if ingested or inhaled, can cause organ damage, skin irritation and respiratory problems -- in the soil and groundwater on the 64-acre property; the site was added to the NPL a year later. Broderick Investment Company was ordered in 1990 to excavate the sludge, which was transferred to a reclamation facility in Alabama. In 1992, the EPA ordered the company and the Burlington Northern Railroad, which operated railroad shops on the property before 1947, to clean up the remaining waste, but they refused; the EPA eventually settled with the Broderick Investment Company and is still trying to recoup money from the railroad. Most of the contamination has been removed, but Broderick won't be taken off the NPL until groundwater standards are met, which could take several more years.
California Gulch, in Leadville, has been on the NPL since 1983. Mining in the eighteen-square-mile area left the Arkansas River polluted with lead and acid-mine drainage. A water-treatment plant has since been built there, and the mining companies responsible for the pollution agreed to help pay for the removal of contamination. The majority of the river cleanup is finished, but the EPA could be in Leadville removing waste from residential yards for another 24 years.
Clear Creek, which runs through Idaho Springs, Central City and into Golden, was contaminated with mine tailings and acidic water from the more than 1,000 mines in Clear Creek and Gilpin Counties; high levels of zinc and cadmium killed a lot of aquatic life in the creek, and lead and arsenic in the water pose health risks to humans. The 400-square-mile watershed was placed on the NPL in 1983, and while the worst of the pollution has been cleaned up, there is still a lot of work left. According to EPA estimates, the cleanup will be done in 2006.
Chemical Sales Company, located on a five-square-mile industrial area in northeast Denver, was placed on the NPL in 1988 after the EPA discovered that nearby groundwater was contaminated with organic materials from the company's chemical storage. Chemical Sales distributed industrial chemicals and detergents. Early studies showed that people drinking, cooking with or bathing in the sullied groundwater were at risk for cancer. The 400 residents who relied on private wells were provided water from the South Adams County Water and Sanitation District, and the EPA removed leaky drums containing the contaminants. Most of the pollution has since been removed, but like the Broderick Wood Products site, Chemical Sales won't be taken off the NPL until groundwater standards are met.
Denver Radium Site actually includes 44 properties throughout the city that were contaminated and then abandoned in the late 1920s after the radium industry collapsed. Radium and its by-product, radon, can cause lung cancer. Most of the sites have been cleaned up since they were first added to the NPL in 1983, including the present location of the Home Depot at 500 South Santa Fe Drive. The last -- and probably the most well-known -- of these sites to be dealt with was the now-defunct Shattuck Chemical Company at 1805 South Bannock Street in Denver's Overland neighborhood, where residents pushed the EPA to remove, rather than simply cap, the radioactive waste. Cleanup is expected to be complete in 2004.
Eagle Mine, along the Eagle River near Vail, produced zinc in the late 1800s and early 1900s; high levels of zinc, arsenic, cadmium, copper and lead were left in the soil and water, and most of the fish died as a result. Drinking-water wells in nearby Minturn were also contaminated; a school and several homes are located near the largest tailings piles. The mine was placed on the NPL in 1986; since the cleanup was initiated, the fish population has increased, and the risks to human health have been eliminated; it should be finished this year.
Lincoln Park is a semi-rural community two miles south of Cañon City, where groundwater was contaminated with molybdenum and uranium from a nearby uranium mill. Although few in the area rely on wells for drinking water, most use the groundwater to irrigate their orchards and gardens and to feed their cattle. Prolonged exposure to molybdenum can cause gout in humans and can poison animals; uranium can cause kidney damage. Lincoln Park was added to the NPL in 1984; since then, residents have been given the option of connecting to the city's water supply, and a treatment wall has been constructed to remove the metals from the groundwater. According to the EPA, the completion date for this site's cleanup is unknown.
Lowry Landfill was a dumping ground for city and commercial waste between 1966 and 1980. Located near Aurora, the Denver-owned, 480-acre former landfill contains acid sludge, petroleum-based oils, pesticides, paint, varnish, sewage sludge and hospital waste, some of which has seeped into the groundwater. The EPA placed Lowry on the NPL in 1984. More than 200 companies and municipalities have since been identified as polluters, including Coors, Conoco, IBM, Gates Rubber Company, the City of Lakewood, Syntex Chemicals Inc. and Shattuck Chemical Company. The EPA estimates cleanup will be done in 2003.
Marshall Landfill once posed a threat to the drinking supply of Louisville residents, but since the site was placed on the NPL in 1983, the problems have been solved. The landfill, located about three miles southeast of Boulder, had leached contaminants into a ditch that carried drinking water from the Marshall Reservoir to Louisville. Between 1965 and 1974, the landfill accepted septic waste, sewage sludge and unidentified hazardous wastes. Benzene, trichloroethylene (TCE) and barium were just some of the dangerous pollutants found in the surface- and groundwater. The parties mainly responsible for the contamination -- the City of Boulder, Browning-Ferris Industries (now owned by Allied Waste Industries) and Cowdrey Corporation -- agreed to pay for the cleanup and to build and operate a water-treatment plant. The contamination has been cleaned up, but the site won't be taken off the NPL until groundwater standards are met.
Rocky Flats is doubtless Colorado's most notorious Superfund site. In 1952, the United States Department of Energy started making plutonium for use in nuclear weapons at this flat spot near the foothills northwest of Denver. The EPA and the FBI shut down Rocky Flats in 1989 for environmental violations, and three years later, after the Cold War ended, the government decided not to resume the production of nuclear-weapons parts at Rocky Flats. But the damage had been done. Liquid plutonium stored in leaky drums, unlined disposal trenches, seeping underground tanks and on-site landfills left much of the soil and groundwater at the 300-acre industrial area contaminated. Other radioactive elements such as uranium and americium have also been discovered in the soil. In 1999, the first shipments of waste were transported from Rocky Flats to a waste isolation plant in New Mexico, and later, more waste was transferred to Nevada. The cleanup effort is expected to continue until 2007.
Rocky Mountain Arsenal was established by the United States Army in 1942 to produce weapons during World War II. Over the next three years, the arsenal made 155,000 tons of chlorine, mustard gas and arsenic trioxide, in addition to 87,000 tons of other chemical products. Following the war, the arsenal leased parts of the 17,000-acre property to companies such as Colorado Fuel and Iron, which made chemicals there; Julius Hyman and Company, which manufactured pesticides; and Shell Oil Company, which produced pesticides, insecticides and herbicides at the arsenal until 1982. The Army and the private companies improperly disposed of waste, leaving behind tainted groundwater. The arsenal was placed on the NPL in 1987, and Congress later passed a law designating the arsenal as a National Wildlife Refuge when the cleanup is complete in 2011.
Summitville, in the San Juan Mountains of southwestern Colorado, was a gold mine that leaked cyanide and acidic and metallic water into the Alamosa River. The contamination killed the aquatic life and got into the irrigation waters that serve the farmland downstream. Summitville had been mined off and on since the 1870s; in the 1980s, Summitville Consolidated Mining Company took over until 1992, when it declared bankruptcy. That year, the EPA stepped in to prevent a catastrophic overflow of cyanide-laden water from seeping into the river; two years after that emergency remediation, the EPA placed Summitville on the NPL. Although the cleanup was expected to have been complete by 2004, the EPA recently announced that it may actually take a century or more.
Uravan Uranium was originally a radium-recovery plant in the early 1900s, but this site in Montrose County was later converted to a uranium- and vanadium-processing facility until it closed in 1984. Radioactive waste from the site, which was operated by Union Carbide, contaminated the air, soil and groundwater around the 450-acre plant, as well as the San Miguel River. Uravan Uranium was added to the NPL in 1986. Umetco, a subsidiary of Union Carbide, is paying for the cleanup, which should be done in 2005.
Vasquez Boulevard and I-70 includes parts of the northeast Denver neighborhoods of Elyria, Swansea, Cole and Globeville. The area was the site of three smelting plants -- the Globe, Argo and Omaha-Grant -- which began refining gold, silver, copper, lead and zinc in the 1870s; the Globe plant still operates. Soil samples in residential yards showed high levels of arsenic and lead, so in 1998, the EPA removed soil outside eighteen homes; the area was placed on the NPL in 1999 and will likely remain a Superfund site until at least 2005.