Superfund Information Systems: Site Profile

Superfund Site:

TAR CREEK (OTTAWA COUNTY)
OTTAWA COUNTY, OK


Site Details



On this page:

Site Background

The following summary on the mine history in Ottawa County is adapted from the Hydrogeologic Characterization Study Report – Tar Creek Superfund Site Operable Unit 4 (CH2M, 2010).

Mining History in Ottawa County

The first ore discoveries and earliest mining operations in Ottawa County, Oklahoma, occurred in the vicinity of Peoria (6 miles east and 1 mile south of Lincolnville) in 1891. The next major ore discoveries occurred 1.5 miles northeast of Lincolnville near Quapaw in 1902, followed by discoveries in 1905 near Commerce. The real expansion of zinc and lead mining at the Site occurred after a major ore discovery in 1914 near the current location of Picher, Oklahoma. Following this discovery, there was a major expansion of mining in what became known as the Picher Field of Oklahoma and Kansas. By 1918, the Oklahoma section of the Picher Field was well defined with 230 mills built or under construction.

Rapid expansion of mining activities occurred during the 1920s, and mining activities reached their peak around 1925. During the early mining period, most mining was conducted by small operators on 20- to 40-acre tracts. Each operator conducted his or her own mining, drilling, and milling activities. By the 1930s, central mills were established, the largest being the Eagle-Picher Central Mill located between Cardin and Commerce, Oklahoma. Many miners ceased their own milling operations in favor of selling their ore production to one of the central mills or having their ore custom milled by these mills. This movement of ore between mines and the central mills resulted in an extensive network of haul roads and rail lines in the district.

With few exceptions, the crude ore produced at the Site was mined using underground mining methods using room and pillar techniques. Pillars were left within the rooms to support the ceilings. To remove the ore, large rooms, some with ceilings as high as 100 feet, were connected by horizontal tunnels known as drifts. Mining activities occurred primarily within a 50- to 150-foot-thick ore-bearing zone within the Boone Formation. The maximum depth of mining was approximately 385 feet below ground surface (bgs). During the peak of mining activities, 130,410 tons of lead and 749,254 tons of zinc were produced annually. Based on production records maintained by the U.S. Department of Interior, Bureau of Mines, a total of 181,048,872 tons of crude ore was produced from the Oklahoma portion of the district. Milling of this ore produced 8,884,898 tons of zinc concentrates and 1,686,713 tons of lead concentrates. With the exception of a limited amount of lead concentrates treated at the Ontario Smelter from 1918 until the early 1930s, all of the concentrates produced from the Site were transported offsite for the conversion of the concentrates to metal by smelting (EPA, 2008).

Depletion of high-grade ores caused a marked decline in annual production after 1946, and depressed metal-market prices and decreased demand for lead and zinc metals forced a cessation of most mining activities in 1958. Smaller mining operations continued in the Picher Field through the 1960s. The last record of significant production from Ottawa County occurred in 1970.

Mining Related Impacts

  • The mill tailings are locally known as chat and primarily consists of fine gravel-sized and coarse sand-sized rock fragments. After the excavated rock was processed and the metal ore extracted, the mining tailings that remained were deposited into piles that were up to 200 feet in height. An inventory conducted in 2005, as part of the remedial investigation (RI) for Operable Unit (OU4), identified 83 chat piles occupying 767 acres, with an estimated volume of 31 million cubic yards (CY), and 243 chat bases (or former piles) occupying 2,079 acres, with an estimated volume of 6.7 million CY (EPA, 2008).
  • In addition to chat, fine tailings ponds containing wastes from the flotation milling process and chat reprocessing operations were produced. Most of the flotation ponds have since evaporated, leaving behind a very fine mining waste sediment that remains on the Site. Fine tailings are either flotation tailings generated during the extraction or milling process or are washed fine tailings generated as a byproduct of washing chat for commercial aggregate sale and from chat reprocessing through the mills. Fine tailings generated from milling and washing chat are currently found in 63 ponds, occupying 820 acres, and total approximately 9.1 million CY, with a makeup of approximately 7.2 million CY (78.7 percent) washed fine tailings and 1.9 million CY (21.3 percent) of flotation tailings (EPA, 2008).
  • When mining operations ceased, it is estimated that underground cavities with a volume of 100,000 acre-feet (161,000,000 CY) had been created. In addition, approximately 100,000 exploratory boreholes were located within the Picher Field, mostly in Oklahoma. Within the Oklahoma portion of the mining district, 1,064 mine shafts existed. In addition, numerous water wells, used for milling operations, were abandoned (EPA, 2005). During the active mining period, groundwater infiltration into the mine workings was a continual problem. Large-scale pumping was required to remove groundwater and maintain dry conditions within the mine workings. When mining activities ceased, pumping from the mine workings ceased as well. The abandoned mine workings began to fill with infiltrating groundwater and surface water inflow through abandoned shafts, open boreholes, and collapse/subsidence features. As the mine workings filled with water, the oxidized minerals began to dissolve, generating a weak acidic solution. The acidic water then reacted with the surrounding rock, further dissolving minerals still contained in the mine workings. This resulted in increases in the concentrations of heavy metals, particularly iron, cadmium, lead, nickel, and zinc, in the water contained within the mine workings. The water also contained high concentrations of sulfate and total dissolved solids, high levels of hardness, and low pH.

Site Background

The Tar Creek Superfund Site is located in Ottawa County, Oklahoma. The Site itself has no clearly defined boundaries, but consists of areas within Ottawa County impacted by historical mining wastes. The Site is part of the larger Tri-State Mining District (TSMD) that consists of historical lead and zinc mining areas in northeast Oklahoma, southeast Kansas, and southwest Missouri. The TSMD is composed of a total of four National Priority List (NPL) Superfund Sites: the Cherokee County Site, Cherokee County, Kansas; the Orongo-Duenweg Site, Jasper County, Missouri; the Newton County Mine Tailings Site, Newton County, Missouri; and the Tar Creek Site, Ottawa County, Oklahoma (MacDonald Environmental Sciences, Ltd.[MESL], 2010).

The Site first came to the attention of the State of Oklahoma and EPA in 1979, when water began flowing to the surface near Commerce, Oklahoma from the underground mine workings, through abandoned mine shafts and boreholes. This surface discharge flowed into Tar Creek, and soon other discharge locations were observed near Tar Creek and the abandoned mining town of Douthat. As a result, most of the downstream biota in Tar Creek were killed. The bottom of the creek became stained red as a result of ferric hydroxide deposition, and red stains appeared on downstream bridge abutments and cliffs in the Neosho River downstream of its confluence with Tar Creek (EPA, 2005).

In 1980, the Governor of Oklahoma established the Tar Creek Task Force, composed of various local, state, and federal agencies, to investigate the effects of mine drainage on the area’s surface water. Based on the information discovered by the Tar Creek Task Force, EPA proposed to add the Site to the NPL (40 CFR Part 300, Appendix B) in July 1981. The Site was added to the NPL on September 8, 1983 (EPA, 2008).

Site Operable Units

Under the National Contingency Plan, an Operable Units (OU) is defined as a discrete action that composes an incremental step toward comprehensively addressing Site problems. This discrete portion of a remedial response manages migration or eliminates or mitigates a release, threat of release, or pathway of exposure. A Site can be divided into a number of OUs, depending on the complexity of problems at the Site. OUs typically address a discrete geographical portion of a Site, specific-Site problems, contaminated media, and the initial phase or phases of action at a Site Because of the complex nature of contamination associated with the Tar Creek Site, Site assessment and remediation has been handled through various investigations and response actions.

The following five OUs have been designated at the Site (EPA, 2008).

OU1 – Surface water/groundwater                 Record of Decision - 1984

OU1 addresses the surface water degradation by the discharge of acid mine water and the threat of contamination of the Roubidoux Aquifer, the regional water supply, from downward migration of acid mine water from the overlying Boone Aquifer through abandoned wells connecting the two. The final remedy for OU1, selected in 1984, included use of diking and diversion structures to reduce the inflow of surface water to three mine shafts at the Site and reduce the outflow of acid mine water from the subsurface to Tar Creek. Construction activities finished in December 1986.

Approximately, 83 abandoned wells that went through the Boone aquifer to the deeper Roubidoux aquifer were plugged to prevent contamination from the Boone aquifer and mine workings from seeping through failed well casings and poorly sealed wells and migrating downward to the Roubidoux aquifer. Abandoned wells that could threaten the Roubidoux are still being discovered and plugged as part of the Roubidoux Groundwater Monitoring Program for OU1. Groundwater quality within the Roubidoux aquifer also continues to be monitored under the Roubidoux Groundwater Monitoring Program (EPA, 2005).

OU2 – Residential areas                  Record of Decision - 1997

OU2 was established to address contaminated soil in residential areas. In 1994, Indian Health Service test results concerning the blood lead levels of Indian children living on the Site indicated that approximately 35 percent of the children tested had concentrations of lead in their blood exceeding 10 micrograms per deciliter, the level of lead in the blood the Centers for Disease Control considers to be a health concern. In August 1994, to address the threat of lead exposure to children, EPA began sampling soils at high-access areas (HAA), such as day cares, schoolyards, and other areas where children congregate. The sampling detected significant concentrations of lead, cadmium, and other heavy metals in surface soils. In March 1995, EPA expanded its sampling activity to include all residences on the Site (EPA, 2005).

In 1995, EPA began to excavate contaminated soil at HAAs and at Site residences, and issued the record of decision in 1997 (EPA, 1997) addressing contaminated soil in the residential areas of OU2. Through 2015, 2,940 residential properties and HAAs have been remediated. New properties that require sampling assessment and remediation are being addressed by ODEQ through a cooperative agreement with EPA Region 6 (EPA, 2015a). The remediation of the yards and the public areas, and the education and outreach programs implemented by the Ottawa County Health Department, are helping to protect the children’s health.

OU3 – Eagle-Picher Office Complex – Abandoned Mining Chemicals     Removal Action - 2000

OU3 was a former office and laboratory complex located in Cardin and operated by one of the former mining companies. Numerous containers of chemicals were found at the Site during 1998 and 1999. One hundred and twenty containers of chemicals were removed as part of a removal response action in 2000. No further action is necessary.

OU4 – Chat Piles, other Mine and Mill Waste, and Smelter Waste        Record of Decision - 2008

OU4 addresses the undeveloped rural and urban areas of the Site where mine and mill residues and smelter wastes have been placed, deposited, stored, disposed of, or otherwise have come to be located as a result of mining, milling, smelting, or related operations. The OU4 ROD was signed in February 2008 and called for a phased approach to address the mining waste over a period of approximately 30 years. The ROD included a residential buyout that was managed by The Lead Impacted Communities Relocation Assistance Trust. The buyout was initiated in 2009and included residents of Picher and Cardin, Oklahoma, and Treece, Kansas (EPA, 2015a). The decision to relocate the residents of Treece, Kansas, was documented in an explanation of significant differences to the OU4 ROD issued in April 2010, and the Lead Impacted Communities Relocation Assistance Trust buyout was complete in 2011 (EPA, 2015a).

The OU4 remedial action activities began in 2009 and are ongoing. These activities include the remediation of rural residential yards not included under OU2; remediation of source materials including a former lead smelter, chat piles and chat bases; the construction of the Central Mill Repository; a fine injection pilot study; transition zone soil contamination; and contamination in water from rural residential wells (EPA, 2008; 2015a). Under OU4 remedial actions, approximately 60 chat piles and chat bases have been remediated; 309,787 tons of chat have been sold (EPA, 2015a); city water was provided to three residences after unsafe drinking water wells were plugged and abandoned; approximately 43,600 tons of chat were injected into underground mine caverns during three chat disposal pilot projects; 40,000 tons of mine waste were contained in an innovative trench/road system; and approximately 58,065 tons of washed chat fines were injected directly into mine caverns eliminating sediment/holding ponds during two additional pilot projects.

OU-4 includes an additional area, called the Catholic 40. The area is a 40-acre tract of land owned by the Quapaw Tribe that has cultural and historical significance. Historical structures include remnants of a Catholic church and school built in 1893. Cleanup included the excavation, hauling, and disposal of 107,000 tons of source material or chat. Chat is the mine waste left at the Site by lead and zinc mining operations.

The University of Oklahoma (OU) continues to operate a passive treatment system (completed in 2008) to treat mine discharges at the Mayer Ranch in Commerce. The Mayer Ranch passive treatment system has improved surface water quality in Tar Creek downstream of the treatment system by addressing approximately 20% of the contaminant mass loading from the mine water discharges (Nairn, 2012). Given the success, feasibility, and cost effectiveness of treating acid mine water discharge with passive treatment, OU and ODEQ partnered to construct an additional passive treatment system in Commerce. The new passive treatment system is located in southeast Commerce where two distinct mining related ponds existed. In 2006, the Oklahoma Conservation Commission filled these two ponds with chat and related debris without installing any sort of water control. Shortly after closure of the features, mine drainage started appearing in several areas as seepage surfaces. The Southeast Commerce passive treatment system (SCPTS) project is planned to addresses the contaminated mine drainage that discharges from upwelling caused by the filling of the subsidence features (Nairn et al. 2014). Construction of the SCPTS was complete in 2016 and is currently operating as designed.

OU5 – Surface Water and Sediments      Record of Decision – future date to be determined

OU5 addresses sediment and surface water. Under OU5, efforts to characterize sediment and surface water throughout the lower Spring and Neosho River basins as well as understand the potential risks associated with exposures to surface water and sediment through a Human Health Risk Assessment (HHRA) are being conducted. This effort is being coordinated with Region 7, 3 states (Oklahoma, Missouri, Kansas), eight Tribes (Quapaw Tribe, Peoria Tribe, Ottawa Tribe, Miami Nation, Eastern Shawnee Tribe, Wyandotte Nation, Seneca-Cayuga Nation, and Cherokee Nation), and the community. OU5 includes 7 watersheds covering approximately 437 square miles and 119 river miles within Oklahoma, Kansas, Missouri, and 8 tribal areas.

Historically, EPA Regions 6 and 7 worked together as part of a multi-state effort to characterize sediment and surface water throughout the Spring and Neosho River basins focusing on ecological risk assessment. Sediment data were collected to evaluate the toxicity of the sediments and develop an advanced screening-level ecological risk assessment (SLERA) of the Tri-State Mining District (MESL, 2010). The advanced SLERA evaluated risks to aquatic organisms associated with exposure to contaminated environmental media. The results indicate that concentrations of metals in sediments commonly exceed conservative toxicity thresholds.

 

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Site Status

ONGOING:   Operable Unit 2 – Residential Areas

The ODEQ continues to work with property owners concerned about potential contamination in their yards. Anyone within Ottawa County is eligible for ODEQ’s Residential Yard Cleanup Program. If you are unsure whether your yard has been cleaned up and would like to get on the list to have your yard or driveway sampled, please contact ODEQ’s Tar Creek Residential Cleanup Project Manager Brian Stanila at (405) 702-5138 or via ODEQ’s toll-free hotline number at 1-800-522-0206, or the EPA Hotline at 1-800-533-3508.

ONGOING:   Operable Unit 4 – Source Material

The EPA continues to work closely with the Quapaw Tribe of Oklahoma (Quapaw Tribe) and the ODEQ on the implementation of the Tar Creek Superfund Site’s (Site) remedy. The EPA continues to award Cooperative Agreements (CAs) to both the Quapaw Tribe and the ODEQ to carry out remedial actions at the Site.

ONGOING:   Operable Unit 5 – Surface Water and Sediment

EPA Regions 6 and 7 are working with 3 states (Oklahoma, Missouri, Kansas), eight Tribes (Quapaw Tribe, Peoria Tribe, Ottawa Tribe, Miami Nation, Eastern Shawnee Tribe, Wyandotte Nation, Seneca-Cayuga Nation, and Cherokee Nation ), and the community to characterize sediment and surface water throughout the Spring and Neosho River basins.

Progress includes:

  • Field Sampling: Sampling activities to collect data to fill gaps identified in the Data Gap Report. Sampling completed in October 2017.
  • Field Sample Plan and Quality Assuurance Plan: final plan detailing the field sampling that will be completed to fill the data gaps idetnified inthe Data Gap Report.
  • Data Gap Report: final report summarizing the memos below as well as the data gaps that need to filled to complete a characterization and risk assessment for surface water and sediment.
    • Human Health Conceptual Exposure Model: a list of the exosure pathways, media, and routes that may result in human exposure.
    • Data Review and Evaluation Criteria: a review and evaluation porcess to determine the applicabilibty of the data resources to project objectives.
    • Data Reference List: list of resources related to surface water and sediment to be used to support project objectives.
  • July 2015: Remedial Investigation and Human Health Risk Assessment Start: The process includes three parts: Data Gap Analysis, Human Health Risk Assessment, and the RI Characterization Report

 

 

 
 

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Work to Protect Human Health and the Environment

Remedial action protects human health and the environment, especially the health of young children.

OU1 – Surface Water/Groundwater   Record of Decision - 1984

Plugging abandoned wells has reduced the potential for contaminants in the shallow Boone Aquifer to migrate to the Roubideax drinking water aquifer. Approximately, 83 abandoned wells that went through the Boone aquifer to the deeper Roubidoux aquifer were plugged to prevent contamination from the Boone aquifer and mine workings from seeping through failed well casings and poorly sealed wells and migrating downward to the Roubidoux aquifer. Abandoned wells that could threaten the Roubidoux are still being discovered and plugged as part of the Roubidoux Groundwater Monitoring Program for OU1. Groundwater quality within the Roubidoux aquifer also continues to be monitored under the Roubidoux Groundwater Monitoring Program (EPA, 2005).

OU2 – Residential Areas                             Record of Decision - 1997

In 1995, EPA began to excavate contaminated soil at public areas and residences in Miami, Afton, Commerce, Fairland, Narcissa, North Miami, Peoria, Quapaw, and Wyandotte (OU2). Through 2015, 2,940 residential properties and public areas have been remediated. New properties that require sampling assessment and remediation are being addressed by ODEQ through a cooperative agreement with EPA Region 6 (EPA, 2015a). The remediation of the yards and the public areas, and the education and outreach programs implemented by the Ottawa County Health Department, are helping to protect the children’s health. As a result, a healthier environment exists for families to enjoy now and in the years to come.

OU3 – Eagle-Picher Office Complex – Abandoned Mining Chemicals     Removal Action - 2000

OU3 was a former office and laboratory complex located in Cardin and operated by one of the former mining companies. Approximately, 120 containers of chemicals were removed as part of a removal response action in 2000.

OU4 – Chat Piles, other Mine and Mill Waste, and Smelter Waste    Record of Decision - 2008

Risks and pathways addressed by the cleanup activities include health risks from people ingesting, touching or inhaling contaminants in soil. Under OU4 remedial actions,

  • approximately 60 chat piles and chat bases have been remediated; 309,787 tons of chat have been sold (EPA, 2015a);
  • city water was provided to three residences after unsafe drinking water wells were plugged and abandoned;
  • approximately 43,600 tons of chat were injected into underground mine caverns during three chat disposal pilot projects and approximately 58,065 tons of washed chat fines were injected directly into mine caverns eliminating sediment/holding ponds during two additional pilot projects;
  • 40,000 tons of mine waste were contained in an innovative trench/road system;
  • More than 2.15 million tons of mine and mill wastes and contaminated soil have been removed from properties and are managed at the onsite repository;
  • more than 570 acres of land have been cleaned up and made available for future reuse; and
  • 17 percent of the source materials removed were purchased directly from property owners by local processors (with transport provided by EPA);
  • voluntary relocation was offered to residents in Pitcher and Cardin, Oklahoma, and Treece, Kanasas, to protect those living in areas with concentrated sources of potential exposure. A total of 628 residences, 74 businesses, and 125 renters were relocated.

EPA is solving two problems at once and helping eliminate hazards from abandoned mine shafts and subsidence features
Addressing abandoned mine shafts and subsidence features is not a specific goal related to reducing the risks of exposure associated with mining-related contamination. However, EPA has taken advantage of utilizing the presence of abandoned mine shafts and subsidence features for the placement of source materials. By placement and capping of the source materials in these features, the footprint of contamination is reduced, and the risk of exposure and the risk of open holes to people and livestock are reduced. In 2013 alone, over 8 percent of source materials removed were placed and capped in onsite subsidence features and/or mine shafts. Since remediation began, over 150 abandoned mine shafts have been filled and capped to reduce the risk of exposure to Site contaminants.

Quapaw Tribe performs the Remedial Action at the Catholic 40
On October 1, 2012, a Cooperative Agreement was signed between EPA and the Quapaw Tribe of Oklahoma to perform remedial action work at the "Catholic 40". The Catholic 40 is a 40-acre tract of land owned by the Quapaw Tribe that has cultural and historical significance. Historical structures include remnants of a Catholic Church and school constructed in 1893. The remedial action involved the excavation, hauling, and disposal of approximately 107,000 tons of source material or chat. The Quapaw Tribe Environmental Office began hauling chat at the Site in mid-December 2013. Extra precautions were taken during these activities in the areas near the historical structures to prevent damage. The remedial action included restoration ( e.g., contouring, seeding) of the Site and bank stabilization of Beaver Creek to ensure the integrity of the remedy. Beaver Creek also has cultural and historical significance to the Quapaw Tribe. This remedial action performed by the Quapaw Tribe is significant because it was the first-ever remedial action in the nation performed by a tribe on property that they own.

ODEQ performs Passive Treatment

The University of Oklahoma (OU) continues to operate a passive treatment system (completed in 2008) to treat mine discharges at the Mayer Ranch in Commerce. The Mayer Ranch passive treatment system has improved surface water quality in Tar Creek downstream of the treatment system by addressing approximately 20% of the contaminant mass loading from the mine water discharges (Nairn, 2012). Given the success, feasibility, and cost effectiveness of treating acid mine water discharge with passive treatment, OU and ODEQ partnered to construct an additional passive treatment system in Commerce. The new passive treatment system is located in southeast Commerce where two distinct mining related ponds existed. In 2006, the Oklahoma Conservation Commission filled these two ponds with chat and related debris without installing any sort of water control. Shortly after closure of the features, mine drainage started appearing in several areas as seepage surfaces. The Southeast Commerce passive treatment system (SCPTS) project is planned to addresses the contaminated mine drainage that discharges from upwelling caused by the filling of the subsidence features (Nairn et al. 2014). Construction of the SCPTS was complete in 2016 and is currently operating as designed.

OU5 – Surface Water and Sediments      Record of Decision – future date to be determined

As this time, there is insufficient information to determine the potential human health risks related to surface water and sediment exposure.  EPA Regions 6 and 7 are working closely with the 3 states (Oklahoma, Missouri, Kansas), eight Tribes (Quapaw Tribe, Peoria Tribe, OttawaTribe, Miami Nation, Eastern Shawnee Tribe, Wyandotte Nation, Seneca-Cayuga Nation, and Cherokee Nation), and the community to develop and complete a human health risk assessment and characterization report. This OU5 effort includes 7 watersheds covering approximately 437 square miles and 119 river miles within Oklahoma, Kansas, Missouri, and 8 tribal areas.

Superfund Job Training Initiative, local labor utilization benefits regional economy
Job creation is just one component of this project's impact on the local economy. EPA continues to work with project contractors to implement the Superfund Job Training Initiative (Super JTI) in Northeast Oklahoma. Super JTI provides job-readiness training and employment opportunities for underserved citizens living in communities affected by Superfund Sites. The Tar Creek program generated 250 interested candidates of which 26 were selected for training. A number of graduates were hired by project contractors and others are awaiting the award of new contracts with hopes of being hired. A success story we have related to this program involves a graduate that has worked on OU4 Site projects since 2010. As a result of his outstanding performance, he was hired as a full time employee by EPA's contractor CH2M HILL in July 2010.

The OU4 and OU2 remedial actions have also provided economic benefits to the local community beyond the sales and marketing of chat. For example, from July 2013 through April 2014, local staff utilization on the Distal 7 North portion of the QU4 remedial action was over 80% of the construction labor, and over 45% of the construction subcontract awards have been made to small disadvantaged businesses, including veteran-owned and woman-owned businesses. For OU2, 40% of construction subcontract awards have gone to small disadvantaged businesses, including woman-owned businesses. These workers have been helping the local economy by spending funds with local vendors.

Five-Year Reviews

EPA has conducted five-year reviews at the Site to ensure that the remedies put in place protect public health and the environment, and function as intended by Site decision documents. The most recent review concluded that response actions at the Site are in accordance with the remedy selected by EPA and that the remedy continues to be protective of human health and the environment in the short term. These review will continue throughout the remediation process and in perpetuity.

 

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Sampling and Monitoring

Operable Unit 2 – Residential Areas

The ODEQ is the lead for cleaning up residential yards for citizens, making the community a cleaner and safer place to live and play. Contaminated mine waste, commonly referred to as chat was used to build roads, parking lots, alleyways, driveways, and used as general fill material. The ODEQ encourages you to ask about having your yard sampled for lead. The ODEQ will be able to tell you whether your property has been sampled, cleaned up, or work with you to find out if sampling and cleanup is necessary. Anyone within Ottawa County is eligible for ODEQ’s Residential Yard Cleanup Program. If you are unsure whether your yard has been cleaned up and would like to get on the list to have your yard or driveway sampled, please contact ODEQ’s Tar Creek Residential Cleanup Project Manager Brian Stanila at (405) 702-5138 or via ODEQ’s toll-free hotline number 1-800-522-0206, or the EPA Hotline at 1-800-533-3508.

Operable Unit 4 – Source Material

During each remediation project, soils are sampled to ensure the remediation goals of the ROD are being met.  All data results are provided in remediation reports that document the work completed for each remediation project.

Operable Unit 5 - Surface Water and Sediment

The Data Gap Report identified data gaps that need to be filled in order to complete the nature and extent investigation and the human health risk assessment. Field sampling activities began July 10, 2017, and were completed in October 2017.

 


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Site Risks

Operable Unit 2 – Residential Areas

 

OU2 focuses only on residential exposure scenarios with emphasis on young children. The risk assessment identified lead as the only Site-related chemical of concern, and identified oral ingestion as the only significant exposure route or pathway. An exposure route or pathway is the way in which contaminants may enter a human being (e. g. inhalation, oral ingestion, and absorption through the skin). Cadmium and zinc are also Site-related chemicals, but the concentrations in the different media (soil, air, drinking water, etc.) for cadmium or zinc were not high enough to exceed acceptable exposure levels.

The elevated concentrations of lead in soil found at many residences at the Site pose a significant health risk to young children living at those residences (or to those children who may live at those residences in the future). Young children (six-years old and younger) who now play (or children six-years-old and younger who may play in the future) in the residential areas on the Site may be exposed to lead through incidental ingestion of lead contaminated soil during normal hand-to-mouth activity during play, and this lead may pose an imminent and substantial endangerment to the health of such children. In addition, lead contaminated soil may be tracked from residential yard soil into the homes of children where it may be ingested during play or at mealtime, and this lead may pose an imminent and substantial endangerment to the health of such children.

The risk assessment identified lead-contaminated soil as the medium which posed the greatest threat to human health on the Site. The EPA selected, a lead remediation goal of 500 parts lead per million parts soil (ppm) for protection of the child resident.

 

Operable Unit 4 – Source Material

The OU4 Remedial action objectives (RAOs) consist of medium-specific or location-specific goals for protecting human health and the environment. The table presents the RAOs and the remediation goals for source material, soil, and ground water at the Site. It outlines the risks identified and provides the basis for evaluating the cleanup options.

Medium

Summary of Remedial Action Objectives

Remediation Goals

Source Material, transition zone soil, and soil which underlies source material

 

Prevent adolescents from coming in direct contact, through the ingestion and inhalation exposure pathways, with lead-contaminated source material where lead concentrations exceed 500 ppm.  The purpose of this objective is to reduce the central estimate of blood lead concentration in adults (i.e., the mature adolescents in question) that have been exposed to source materials to a level that ensures that the 95th percentile fetal blood lead concentration in their offspring does not exceed 10 µg/dl.  This objective will also be protective for children who live on-site in the event they come in direct contact with the source material through the ingestion and inhalation exposure pathways.

 

Prevent terrestrial fauna from coming in direct or indirect contact, through the ingestion exposure pathway, with

cadmium-, lead-, or zinc-contaminated source materials and soils  where cadmium, lead, and zinc concentrations exceed their respective remediation goals of 10.0 mg/kg, 500 mg/kg, and 1100 mg/kg.  By indirect contact EPA means contact with these contaminants via ingestion of plants grown in contaminated source materials and soil.

 

 

General Tactics:

To meet the above remedial action objectives for source material, the remedy selected in this ROD calls for excavation of source materials to native soils with confirmation samples to ensure the remediation goals are met.    The selected remedy calls for a minimal footprint of source material and maximum unrestricted use of Site land.

 

Adolescents:

500 ppm lead in source material in transition zone soil, and in the soil which underlies source material.

 

 

 

Terrestrial Fauna:

 

10.0 mg/kg cadmium, 500 mg/kg lead and 1100 mg/kg zinc in source material, smelter waste, in transition zone soil, and in the soil which underlies source material.

 

 

 

 

Source Material, transition zone soil, and soil which underlies source material

 

Prevent riparian biota including waterfowl from coming into contact, through the ingestion exposure pathway, with unacceptable concentrations of lead, cadmium, and zinc in surface water and sediment by eliminating all discharge of cadmium, lead, and zinc from source materials to surface water.

Zero discharge of cadmium, lead, zinc from source materials to surface water.  [By zero discharge EPA means discharge concentration levels that would be consistent with the concentration levels that would be expected from soil that has background concentrations of these chemicals.]

Soils

 

Prevent children from direct contact, through the ingestion and inhalation exposure, with lead-contaminated soil where soil lead concentrations exceed 500 ppm.  [The purpose of this objective is to limit exposure to soil lead levels such that a typical (a hypothetical) child or group of similarly exposed children living on site would have an estimated risk of no more than 5% exceeding 10 µg/dL blood lead level.]

 

General Tactics:

To meet the above remedial action objective, the remedy selected in this ROD calls for excavation of residential yard soil up to a maximum depth of 12 inches or until soil concentrations no longer equal or exceed 500 ppm, whichever calls for less soil to be excavated.

 

Prevent terrestrial fauna from coming in direct or indirect contact, through the ingestion exposure pathway, with cadmium-, lead-, or zinc-contaminated soil where cadmium, lead, and zinc concentrations exceed their respective remediation goals of 10.0 mg/kg, 500 mg/kg, and 1100 mg/kg.    By indirect contact EPA means contact with these contaminants via ingestion of plants grown in contaminated soil.

 

General Tactics:

To meet the above remedial action objective, the remedy selected in this ROD calls for excavation of visible source materials down to native soils with confirmation samples of the soil taken to ensure that remediation goals are met.

 

Children:

500 ppm lead in soil

(See OU2 Record of Decision for Tar Creek Residential Areas)

 

 

 

 

 

 

 

 

 

 

Terrestrial fauna:

 

10.0 mg/kg cadmium, 500 mg/kg lead and 1100 mg/kg zinc, in transition zone soil, and in soil underlying source material.

Ground water

Prevent Site residents from the ingestion of water from private wells that contains lead in concentrations exceeding the National Primary Drinking Water Standards.

 

General Tactics:

To meet the above remedial action objective, the remedy will include an alternative water source for those residences affected.

 

0.015 mg/L lead at the water tap

 

 

OU5 – Surface Water and Sediments      Record of Decision – future date to be determined

As this time, there is insufficient information to determine the potential human health risks related to surface water and sediment exposure.  EPA Regions 6 and 7 are working closely with the 3 states (Oklahoma, Missouri, Kansas), eight Tribes (Quapaw Tribe, Peoria Tribe, Ottawa Tribe, Miami Nation, Eastern Shawnee Tribe, Wyandotte Nation, Seneca-Cayuga Tribe, and Cherokee Nation), and the community to develop and complete a human health risk assessment and characterization report. This OU5 effort includes 7 watersheds covering approximately 437 square miles and 119 river miles within Oklahoma, Kansas, Missouri, and 8 tribal areas.

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Community Resources

Community involvement is the process of engaging in dialogue and collaboration with community members. The goal of Superfund community involvement is to advocate and strengthen early and meaningful community participation during Superfund cleanups.

EPA is committed to engaging dialogue and collaboration with community members.  Our goal for Superfund community involvement is to advocate and strengthen early and meaningful community participation during Superfund cleanups.  We strive to encourage and enable community members to get involved.   EPA is committed to:

  • Listen carefully to what the community is saying
  • Take the time needed to deal with community concerns
  • Change planned actions where community comments or concerns have merit
  • Keep the community well informed of ongoing and planned activities
  • Explain to the community what EPA has done and why

Community Participation - EPA welcomes the opportunity to improve our communication effort by obtaining feedback and suggestions from you.  Do you have suggestions that can improve the exchange of information or ideas that can enhance the implementation of the remediation efforts?  If so, we want to hear from you.  Your participation can make a difference!

Community Involvement Plan (CIP) -  The site CIP has been developed to identify the concerns, needs and issues of the community.  This document informs the site team about the community and the preferred ways to involve them in the site clean-up

Please follow this link for a wide variety of community involvement information: Community Involvement Resources

Information Repositories

Information Repositories containing the Administrative Record including the Record of Decision (ROD), for the Tar Creek Superfund Site is available at the following locations: 

Miami Public Library
200 North Main Street
Miami, Oklahoma   74354
918.542.2292

Oklahoma Department of Environmental Quality
707 North Robinson – 2nd Floor
Oklahoma City, Oklahoma   73102
405.702.1188 or 405.702.1000

All inquiries from the news media should be directed to the Region 6 Press Office at 214.665.2200.

 


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Redevelopment

Sustainability through re-use or recycling of Site materials is another focus for the remedial action. Trees removed from the work areas during construction are segregated from other wastes to allow re-use and recycling where possible. Root balls from vegetative clearing may have contaminated soil attached, and are transported to the Central Mill Repository, but waste trees and other wood debris are available for mulching. Sampling and analysis of the chipped waste tree and wood debris material is performed, and results indicate concentrations of lead, cadmium and zinc are well below the cleanup goals and Regional Screening Levels for residential soil. From the Distal 7 North Site alone, over 2,000 cubic yards of mulch was provided to a local company for use as mulch. Remedial activities at the Distal 7 South Site have yielded 2,115 cubic yards of mulch.

The cleanup addresses residential relocation and sale of chat (a mining waste). EPA does not own any chat and will not purchase any chat. However, it is assisting chat sale participants, including the Quapaw Tribe of Oklahoma and local chat processors, as part of the Site’s Superfund remedy. Approximately, 17 percent of the source materials removed were purchased directly from property owners by local processors (with transport provided by EPA) for use.

Residential, commercial and public uses continue on several cleaned up properties. Reuses for properties currently undergoing cleanup are typically agricultural or rural. To date, workers remediated 2,940 properties under OU2.


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