Tar Creek Superfund site

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Tar Creek
Superfund site
Tar Creek Superfund site 2008.jpeg
Geography
City Picher
County Ottawa County
State Oklahoma
Information
Progress
Superfund sites

Tar Creek Superfund site is a United States Superfund site located in Picher and Cardin, Oklahoma. Chat piles left behind by the mining companies contain lead dust that has blown around the city. Elevated lead levels in Picher children have led to learning disabilities and other problems. The lead and zinc have also seeped into groundwater, ponds, and lakes, many of which still are used by children for swimming. Since the children of Picher have been found to have elevated levels of lead in their bodies, the EPA has since declared Picher to be one of the most toxic areas in the United States.[1][2] The Tar Creek Superfund site is the Oklahoma section of three sites that together encompass the Tri-State district. This is an old lead and zinc mining district that was spread across southwest Missouri, southeast Kansas, and northeast Oklahoma.

Origins of the Tar Creek Superfund Site[edit]

This image, taken in 2010, shows a chat pile near Picher, Okla. These piles contain lead-contaminated dust and are one of the reasons the area was designated a Superfund site.

The area now known as Tar Creek is part of the Tri-State mining district, an area of 1,188 square miles located in Ottawa County, Southwestern Missouri and Southeastern Kansas. The first mining activities took place in Missouri around 1850. By 1908, sites had been started in Miami, Picher, and Commerce. Railroads being built in the area greatly increased production. Mining quickly had a high economic impact, and by 1924 most of the young, American born whites in the district were employed by the mining industry.[3]

When mining began in the area, most of the land was owned by the Quapaw tribe. An 1897 ruling and subsequent lawsuits determined mining was allowed to commence in the area, but only about one sixth of Quapaw landowners were allowed to collect royalties. Between 1915 and 1930, decreasing demand and production caused companies to buy the land rather than lease it, which encouraged high consolidation of mining companies.[3]

1926 was the highest year of production in the area, and Ottawa county became the world's largest source of lead and zinc. During World War I, the region supplied 45 percent of the lead and 50 percent of the zinc used by the U.S. Further advances in technology also increased production. Between 1908 and 1950, the entire Tri-State Mining Region generated over an estimated 1 billion U.S. dollars. After 1950, many of the mines were shut down largely due to environmental impacts.[3]

National and State Intervention[edit]

The mining waste was located very near neighborhoods in the town of Picher.

On December 11, 1980, the Congress passed the The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA).[4] This law was passed due to the discovery of health and environmental hazards found in sites across America, such as Times Beach and Love Canal. The environmental programs and initiatives established by CERCLA are referred to as the Superfund. The EPA established a Hazard Ranking system and a National Priorities List in 1981 and 1982, respectively. The Tar Creek site was designated a Superfund site in 1983, and work on the first Operable Unit (OU) occurred in 1984.[5]

In 2004, the state of Oklahoma enacted the Oklahoma Plan For Tar Creek. However, in 2006, most of this money was reallocated to a relocation program, due to the immediate health hazards to those still living in the area.[5]

Health and Environmental Hazards in the Tar Creek Region[edit]

Main article: Lead poisoning
Main article: Zinc toxicity

"Dry" and "wet" methods were used to extract pure lead from ore. Dry methods produced chat piles, and wet methods required tailing ponds to process ore into a usable product (see Chat (mining) and Tailings). An estimate cited in the Oklahoma Plan for Tar Creek claimed around 75 million tons of chat piles exist, while the exact amount of tailings is unknown.[5] Chat piles are simply large mounds of mining waste. It was not uncommon for children in the area to play around the chat piles, such as riding bikes up and down the large piles or swimming in contaminated waters. Some of the piles were even used for track practice.[1][6]

Lead poisoning is especially hazardous to children under six years of age.[5] High levels of lead at this age can produce lifelong problems associated with impaired neurological development. A 1996 study showed 35% of children ages 1–5 had blood lead concentrations above the threshold considered dangerous by Federal Standards (more recent reports show this number to be lower[7]). Furthermore, the miscarriage rate in the area is 24%, compared to the national average of 10%.[6] Empty mines also present a more immediate danger due to mine collapses. One collapse in 1967 took nine homes.[1]

Lead can also have marked environmental impacts, especially in aquatic systems. Water from the region eventually drains into the Grand Lake o' the Cherokees. This has led to raised levels of lead in the lake, and there is currently an advisory to limit the number of fish consumed by fishermen in the area.[7]

Damage to Water Resources and Aquatic Life[edit]

Often, waste materials from mining were dumped into exploration holes dug to map out mining areas. After mining ceased in the 1960s, the mines flooded and these waste materials began to mix in with the rest of the water that filled the mine. Eventually, this water reached the surface and formed "springs" of contaminated water at the site of the exploratory drilling holes. The first record of contaminated water in the town's aquifer occurred in 1980.

To keep groundwater from saturating the mines while they were active, water was pumped out of mines. This created a large depression where mining activities occurred. Mined out portions were used to store waste materials and poor quality ore instead of removing them from the mines. These waste materials reacted with moist air and oxidized. When mining ceased, so did the active pumping of water out of the mines. Thus, water flowed back into the depressions left by mines, and reacted with the oxidized and now more reactive heavy metals left over. Eventually, enough water filled the mines that they exceeded the elevation of the area, thus allowing water to travel to the surface.The first contaminated springs of water occurred in 1979, and in 1980 Picher first recorded contaminated water from the town's aquifer.[8]

Estimates in 1982 showed lead and cadmium levels in the underground aquifer of Picher were five times the standards for drinking water.[8] Thus, it is necessary to treat mine water to avoid mine water contaminating other clean water sources, such as nearby Grand Lake, which already has elevated levels of lead, due to mining activities (see above). Since heavy metals cannot be disposed of by photosynthetic organisms in the water, they accumulate heavy metals. Then, any consumer who then feeds on this primary producer accumulate higher concentrations of these contaminants, as the primary producer has a higher concentration of heavy metals relative to the water. Secondary and tertiary consumers accumulate even higher concentrations of these metals by the same logic (for more information on this process, see biomagnification). Since humans consume fish rather than phytoplankton, we are at best a secondary consumer, and lead poisoning from fish in contaminated lakes becomes likely.

Remediation efforts[edit]

Since the passage of CERCLA, numerous remediation efforts have occurred in the area. The Oklahoma Plan for Tar Creek has listed four main objectives in the process: improving surface water quality, reducing exposure to lead dust, attenuating mine hazards, and land reclamation.[5]

To improve water quality, the University of Oklahoma has implemented a 1.2 million dollar passive water treatment system. This system uses gravity and renewable energy to flow water through a filtration system, composing of aerobic and anaerobic bacteria treatments, and periodic oxidation of treated waters. This project has shown to greatly reduce the presence of dangerous heavy metals in treated waters.[5][7]

To reduce the exposure to lead dust, the Oklahoma plan for Tar Creek calls to reduce exposure by paving over chat roads and otherwise encapsulating chat to avoid airborne lead dust. One of the objectives of this plan is to determine the maximum amount of chat that can be mixed with asphalt while minimizing the risk of exposure. A chat and asphalt mixture may also be used to fill mines, which will reduce the threat of mine hazards--namely, the collapse of mines and/or the exposure to lead due to open or collapsed mines.[5][7]

Finally, the plan calls for the restoration of the land damaged by mining activities. After the direct threat of lead in chat piles is addressed, land will then be revegetated or removed and replaced by new soil. One 2011 estimate claims an additional 3.2 million dollars will be sufficient to remediate the more than 400 mining sites remaining in the area.[5][7]

Documentary Film[edit]

The Tar Creek Superfund site was the subject of a documentary film, Tar Creek. This documentary came out in 2009 and was written, directed, and narrated by Matt Myers. The film covers the gamut of the issues surrounding the Tar Creek Superfund site, including lead poisoning, mine waste, acid mine water, sinkholes, governmental racism against the Quapaw Tribe, the downstream expansion of the superfund site, and the eventual federal buyout of the citizens.

During the Fall of 2010, Tar Creek toured to many of the nation's existing Superfund sites as part of the Superfund Screening Tour. Universities, organizations, churches, and schools used the story of Tar Creek to have a discussion about what could happen in their communities.

See also[edit]

References[edit]

Specific pages used in the Oklahoma Department of Environmental Quality page (Reference #5) included in the external links section

External links[edit]

Coordinates: 36°58′32″N 94°50′17″W / 36.97556°N 94.83806°W / 36.97556; -94.83806