University of Nebraska–Lincoln, LLWR Disposal Site (State of Nebraska)
This site description was provided by the cognizant Agreement State, and the U.S. Nuclear Regulatory Commission (NRC) makes no claim regarding the validity of the information provided. See our Site Disclaimer for more information.
1.0 Site Identification
|Type of Site:||Unknown|
|Project Manager:||Teresa Mixon (NRC Decommissioning Contact)|
2.0 Site Status Summary
During World War II and the Korean War 30,000 acres near Mead, Nebraska were used by the US military as the Nebraska Ordnance Plant (NOP) to manufacture bombs. TCE and RDX were two of the primary active ingredients of the munitions. The Load Lines were routinely washed down to prevent the build up of the above chemicals. These chemicals made their way into the groundwater and created plumes that eventually found their way to nearby groundwater wells. Following the deactivation of the NOP, approximately 9630 acres were given to the University of Nebraska. The University disposed of hazardous waste consisting of chemicals, pesticides and radioactive material in several trenches. Seven trenches contained radioactive material. Historical records of the radioactive material disposal indicated at present (September 2007) inventory of 61 millicuries of Carbon-14, 0.4 millicuries of Cobalt-60, 44.6 millicuries of tritium (H-3) and 5.2 millicuries of Technetium-99 spread over the seven trenches in 3 disposal locations. The disposal locations are Load Line #1 (LL#1), Load Line #2 (LL#2) and Burial Site D (BS-D). Load Line indicates the disposal location's proximity to the bomb factories and Burial Site D is near a Natural Resources District reservoir and former sewage treatment plant. LL#1 disposal location consisted of two trenches. One was approximately 100 feet long and the second was approximately 20 feet long. LL#2 disposal location was one trench approximately 60-70 feet long. BS-D consisted of four trenches varying in length from 100 feet to 20 feet long. All trenches were approximately 2 to 3 feet wide. The waste consisted of tens of thousands of liquid scintillation vials, animal carcasses and other laboratory/medical waste. The EPA declared the NOP property a Superfund site and because the University of Nebraska disposed of hazardous waste on their portion of the NOP property they were required to remediate their disposals under CERCLA. The EPA worked in conjunction with the Nebraska Department of Environmental Quality (NDEQ) and Nebraska Department of Health and Human Services, Radioactive Materials Program (NDHHS). The University of Nebraska and Nebraska Department of Health and Human Services, Radioactive Materials Program (NDHHS) both ran the RESRAD radiation dose computer model to determine the radioactive hazard to a resident farmer who got all of his food and water from the site. It was modeled to have all the radioactive material in one area (not spread out over 3 disposal locations miles apart). This was designed to present the worst case scenario. The dose modeling showed that exposures were below regulatory concern (<15 mrem/yr). This meant the site was already below the level to be released for unrestricted use prior to decommissioning work. The waste and impacted soil (hundreds of cubic yards) were segregated as to type and hazard and sent to various waste processors and disposal facilities for final disposition. Most radioactive waste has been sent off-site. A Final Status Survey (FSS) was performed using the Multi-Agency Radiation and Site Investigation Manual (MARSSIM). All radioactive isotopes had to fall below their Derived Concentration Guideline Levels (DCGLs). Since there were multiple radioisotopes the sum of fractions methodology was employed to ensure the total annual dose did not exceed 15 mrem. The University has completed their analyses for all their disposal locations and their radiological results meet the criteria. NDHHS had taken split-samples at all three disposal locations. NDHHS has cleared LL#1, LL#2 and BS-D for unrestricted release. Chemical contaminants keep the sites open while continued remediation continues. NDHHS anticipates the EPA will allow closure by no later than June 1, 2008.
3.0 Major Technical or Regulatory Issues
The University of Nebraska is an active licensee and the disposals had taken place in the 1970s under the regulations in place at the time. There were no issues (other than weather) that impacted the radiological decommissioning schedule. The State project manager is Bruce Haley.