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The Barnwell Facility (the “Barnwell Facility” or the “Facility”) is a low-level radioactive waste (“LLRW”) disposal facility in Barnwell County, South Carolina. It is located on approximately 235 acres of property owned by the State of South Carolina and leased by the operator, Chem-Nuclear Systems, LLC, (“Chem-Nuclear”) from the State Budget and Control Board. Barnwell only disposes of LLRW. It does not accept high-level radioactive waste or hazardous waste.
View the DHEC publication on radioactive waste management.
The Barnwell Facility is licensed and regulated by the South Carolina Department of Health and Environmental Control (“DHEC”). This authority is delegated to the State of South Carolina by the United States Nuclear Regulatory Commission through a formal agreement under the federal Atomic Energy Act. South Carolina is thus referred to as an “Agreement State.”
Chem-Nuclear operates the Facility pursuant to DHEC License 097. DHEC issued a LLRW storage license to Chem-Nuclear in 1969 and a disposal license in 1971. Chem-Nuclear has been the sole operator of the Facility, although there have been changes in Chem-Nuclear’s parent company. Over the years, License 097 has been amended 49 times to update and strengthen regulatory requirements. The License must also be renewed every 5 years. License 097 has been renewed 7 times. Renewal of the license had never been challenged until 2004 when the most recent renewal was appealed by the Sierra Club. As discussed below, the Administrative Law Court (“ALC”) upheld DHEC’s decision to renew the license, and the Sierra Club has filed an appeal of the ALC decision.
The licensing requirements regarding possession and disposal of radioactive materials are set out in DHEC Regulation 61-63. Part VII of that regulation governs the licensing and regulation of LLRW disposal facilities. It contains requirements regarding the license application process and the technical information required, license conditions, siting, design, operations, standards for the protection of the public and employees, monitoring, financial assurance, closure, postclosure and maintenance, and termination of a license.
RHA 7.18 of Part VII establishes specific limits on the level of radioactive materials that may be potentially released to the general environment from a LLRW disposal facility. This section and a corresponding condition of License 097 require that Chem-Nuclear demonstrate that during operations and after closure the concentrations of radioactive materials that may be released from the Facility to the general environment will not result in an annual dose exceeding 25 millirems (“mrem”) to a hypothetical person’s whole body, 75 mrem to the thyroid and 25 mrem to any other organ of the body. To put these limits in context, a routine chest x-ray provides a dose of about 20 mrem; and according to the National Council on Radiation Protection and Measurements Report No. 93, the estimated annual dose to an average American from all background radiation sources is about 360 mrem per year.
The release limits are measured as an annual dose rate to a hypothetical person who consumes water at the point of compliance at the rate of two liters per day for a year. The point of compliance for the Facility is the point at which water flows from property owned by Chem-Nuclear onto the Savannah River Site (“SRS”). There is no actual person consuming water at this point of compliance. As discussed below, Barnwell is and will remain in compliance with these limits.
In addition to these specific numerical standards, RHA 7.18 also requires that “[r]easonable effort should be made to maintain releases of radioactivity in effluents to the general environment as low as is reasonably achievable.” The acronym for this requirement is “ALARA.” DHEC requires compliance with ALARA regarding releases to the general public and to workers at the Facility. DHEC has determined that the Barnwell Facility complies with ALARA. Compliance with ALARA was also an issue in the license renewal litigation brought by the Sierra Club. As discussed below, the ALC determined that the Barnwell Facility is adhering to ALARA.
In addition to licensing the Facility, DHEC carefully oversees and monitors operations at the Facility. DHEC maintains an on-site inspector at the Facility who checks each waste shipment to determine compliance with federal and State requirements. DHEC further conducts weekly inspections of disposal facility operations and unannounced semi-annual inspections of the entire Facility. DHEC also reviews environmental monitoring data to determine compliance with regulatory requirements. In addition to regulating the Facility itself, DHEC also permits and regulates generators of LLRW pursuant to DHEC Regulation 61-83.
Chem-Nuclear has a documented history of excellent regulatory compliance. There have been no environmental releases above regulatory limits and no radiation exposures above regulatory limits to the public from operations. No notices of violation or items of noncompliance have been issued against License No. 097 since 1983. Radiation exposures to Barnwell employees are well below the annual limit for occupational workers. The last lost time injury at Barnwell was in 1993.
The disposal technology utilized by Chem-Nuclear Systems, LLC, (“Chem-Nuclear”) at the Barnwell Low-Level Radioactive Waste (“LLRW”) Disposal Facility (the “Barnwell Facility” or the “Facility”) has been continually revised and updated over the life of the Facility to improve its performance and protection of the public and the environment. DHEC has also revised and strengthened its disposal regulations, and its current regulations are more stringent than the requirements promulgated by the U. S. Nuclear Regulatory Commission (“NRC”). The technology currently utilized at the Barnwell Facility is best described as enhanced shallow land disposal. Key components of this technology include the following:
• engineered trenches, the design and construction of which are approved by the South Carolina Department of Health and Environmental Control (“DHEC”);
• the use of improved containers for disposal of LLRW, including high integrity containers (“HICs”), and a requirement of solid waste forms (i.e., no liquids);
• the use of vaults which provide structural stability for trenches; and
• the use of enhanced multi-layer final caps, including a synthetic layer, to prevent infiltration of water through the trenches.
In the mid-1990’s, DHEC undertook a comprehensive review of its disposal regulations to determine what, if any, portions of the North Carolina design should be incorporated into requirements for the Barnwell Facility. As a result, DHEC promulgated changes to Regulation 61-63, including the requirements to utilize concrete disposal vaults and to install a multi-layer final cap to improve long-term performance. DHEC chose not to incorporate certain other aspects of the North Carolina design such as the synthetic liner beneath the disposal units and the capability for leachate removal. The key concern was additional radiation exposure to workers in managing and disposing of the leachate.
Chem-Nuclear conducts an extensive environmental monitoring program involving sampling and analysis of groundwater, surface water, air, soil, and vegetation. The Facility has a system of about 180 groundwater monitoring wells, located both on site and off site, that have been installed by Chem-Nuclear and the U. S. Geological Survey. Samples from these wells are collected quarterly and analyzed for radioactivity as directed by DHEC. All results are reported to DHEC. On-site and off-site surface water is also sampled and analyzed. Chem-Nuclear maintains air samplers around the boundary of the site, and filters from these samplers are collected and analyzed on a bi-weekly basis. Direct radiation at the site boundaries is monitored continuously by thermoluminescent dosimeters (“TLDs”). The results of the collection and analysis of monitoring data establish that the Facility complies with all applicable regulatory standards and will continue to do so in the future.
Certain radionuclides have been detected in the groundwater monitoring wells at the Facility. Tritium, which is a radioactive isotope of hydrogen, has been detected at the compliance point. Tritium easily exchanges with the hydrogen in water, and thus it migrates with groundwater. Tritium has a half-life of 12.3 years, which means that one half of its radioactivity will decay in that time. Tritium was first detected in groundwater monitoring wells in the late 1970’s. The source of the tritium is LLRW disposed of at the Facility, primarily as a result of early disposal practices which did not meet the much more stringent current requirements regarding containment and waste forms.
Since discovering tritium in the groundwater beneath the Facility, Chem-Nuclear has taken a number of steps to minimize potential migration of radionuclides at Barnwell. These steps include improvements to trench designs to minimize water flow, improvements to waste forms including solidification and/or elimination of any liquids, improvements to waste containers including use of polyethylene High Integrity Containers (“HICs”), use of vaults which provide stability to the waste containers, and enhanced covers on the trenches to eliminate infiltration of water into the trenches.
The combined effect of these measures is to reduce substantially the amount of tritium and other radionuclides migrating from the trenches. The maximum tritium concentration measured at the point of compliance at Mary’s Branch Creek was calculated to be a dose of 5.7 mrem per year, about 1/5 of the limit set by DHEC regulation. Groundwater computer models project the hypothetical maximum concentration of tritium at the point of compliance to be 13 mrem per year, or about 1/2 of the limit set by DHEC requirement. As discussed above, these limits apply to a hypothetical person continuously consuming water at the point of compliance. There are no actual persons likely to come into contact with or drink water at the point of compliance in Mary’s Branch Creek. Also, there are no drinking water wells in the downgradient vicinity of the Facility.
1. The Environmental Radiological Performance Verification (“ERPV”)
The ERPV is a detailed study of the Barnwell Facility to determine whether it will meet the performance standards set by DHEC into the long-term future. The ERPV was prepared by Chem-Nuclear at the request and direction of DHEC. Although initiated prior to the latest license renewal process, the EPRV became an integral part of the renewal process. The ERPV, which was conducted over a period of several years and produced multiple volumes of work, utilized extensive actual data collected at the Facility and predictive computer models to demonstrate that the Facility will meet DHEC performance standards over at least a 2000-year period.
The ERPV analyzed both water and air pathways of exposure to radiation. It concluded that the maximum hypothetical dose rate through a water pathway would be 13 mrem per year, about 1/2 of the DHEC limit. The actual dose rate, however, would be negligible because there are no known consumers of surface water downgradient of Chem-Nuclear’s property. The air studies conducted determined that there was no measurable dose to any member of the public through any airborne release.
2. The “Blue Ribbon” Panel
DHEC conducted a careful and thorough review of the ERPV. DHEC commissioned and funded a panel of eight experts, referred to as the “Blue Ribbon” Panel, to review the ERPV to determine its validity. The Blue Ribbon Panel was comprised of recognized experts in several disciplines, including radiological assessment, hydrology, geology, and engineering. The Panel reviewed various iterations of the ERPV and provided comments and suggested changes which Chem-Nuclear addressed and incorporated in a subsequent report. As a result of addressing the Panel’s recommendations, there were no substantive changes to the earlier findings of the ERPV with one exception. The Panel recommended removing some of the conservatism in the ERPV calculations, such as not taking into account the decay rate of tritium. When Chem-Nuclear incorporated the Panel’s recommendation, the maximum hypothetical dose rate at the compliance point was determined to be even lower and is currently projected at 13 mrem per year.
Among the conclusions of the Panel in its final report were that the Barnwell Facility poses a minimal risk to either the public or the environment at the present time as well as into the long-term future. The Panel also concluded that current disposal practices are adequate and that alternative technologies would provide only incremental improvement, if any, in the performance of the Facility.
3. License Renewal Proceedings
In April of 2000, Chem-Nuclear timely submitted an application to DHEC to renew License No. 097 for the eighth time. In March of 2004, following a detailed review of the permit application which included the ERPV, the Blue Ribbon Panel report, and the Technical Evaluation Report which detailed the technical basis for renewal of the license, DHEC issued an amendment renewing License No. 097. As indicated earlier, the Sierra Club filed a petition seeking review by the ALC of DHEC’s license renewal decision. The Sierra Club raised a number of arguments, including that current disposal practices do not meet regulatory standards, including ALARA, and that DHEC should require use of alternative technologies. After a lengthy four-day hearing in which extensive expert testimony was presented, the Court concluded that the Sierra Club had failed to present sufficient evidence to warrant reversal of DHEC’s decision and issued an order sustaining its decision to renew License No. 097.
The ALC also ordered that Chem-Nuclear conduct a study concerning possible methods to reduce contact between LLRW and water at the Facility and to submit the study to DHEC within 180 days of the date of the Court’s order, which was issued on October 13, 2005. The Court specifically directed that Chem-Nuclear evaluate designs and operational procedures that would (1) shelter the disposal trenches from rainfall and prevent rainfall from entering the trenches, (2) provide temporary dry storage facilities for the storage of waste received during wet conditions, and (3) provide for the sealing and grouting of the concrete disposal vaults to prevent intrusion of water to the maximum extent feasible.
Chem-Nuclear timely submitted the study which is now under consideration by DHEC. The results of the study demonstrated that placing roof structures over the trenches to prevent rainfall from entering the trench and sealing and grouting the vaults would result in increases in worker dose that would significantly exceed the potential savings in environmental dose to a hypothetical consumer of water at the compliance point. Thus, Chem-Nuclear recommended that those changes not be implemented. Chem-Nuclear proposed to continue its procedures for providing temporary dry storage for waste received during wet conditions. Chem-Nuclear will of course implement whatever design and operational changes are determined to be appropriate by DHEC.
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