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Routine Radiological Environmental Monitoring. Ronald Warren Ecological & Environmental Monitoring National Security Technologies, LLC Community Environmental Monitoring Program Workshop July 26, 2011. Overview. Routine Radiological Environmental Monitoring Plan (RREMP) overview
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Routine RadiologicalEnvironmental Monitoring Ronald Warren Ecological & Environmental Monitoring National Security Technologies, LLC Community Environmental Monitoring Program Workshop July 26, 2011
Overview • Routine Radiological Environmental Monitoring Plan (RREMP) overview • Operations evaluations against regulatory limits • Evaluation that indicated soil re-suspension less than National Emissions Standards for Hazardous Air Pollutants (NESHAPs) • Standards vs. RREMP results • NESHAPs standards vs. results • Compliance is demonstrated at the on-site locations, so the off-site dose is much less
RREMP • Identifies requirements for radiological monitoring at Nevada Site Office facilities, primarily the Nevada National Security Site (NNSS) • Focuses on • the need to ensure that the public and • the environment are protected, • that compliance with the letter and the • spirit of the law is achieved, and • that good land stewardship is • practiced. • Uses a decision based approach to identify • the data that must be collected and • provides Quality Assurance, Analysis, and • Sampling Plans which ensure that • defensible data is generated. Routine Radiological Environmental Monitoring Plan
Pathway Approach • Inhalation (Air) • Ingestion • Groundwater • Game Animals • Direct Exposure (External Dose)
Pre-Operational Evaluations • Projects with a potential for airborne radionuclide emissions are evaluated (modeled) in accordance with 40 CFR 61 for the potential to cause a 0.1 mrem dose to the public under the assumption no pollution controls are in place. • If the modeled emission exceeds 0.1 mrem, the regulator is required to be involved with the design, and monitoring will likely be required (e.g. JASPER).
Modeling of Potential Off-site Dose • For potential emissions (before a new potential emission source is created to determine off-site dose) • To estimate dose from actual emissions because concentrations of radionuclides from most emissions are so low they cannot be measured even relatively near the emission source. How do we know modeled results are valid (conservative)?
Modeled vs. Measured Results (continued)
Air Monitoring Air Particulate Sampling Atmospheric Moisture Sampling Emergency Response (e.g. wildfires) or for Special Projects Air Sampler – Solar Power Air Sampler – Line Power
239+240Pu Annual Mean Trends Average Trend Lines for Locations With > 15-Year Histories Since 1971 3 to 9% avg. annual decrease
3H Average Trends by Area Group ~15% avg. annual reduction
Water Monitoring Surface Water Groundwater Monitoring Wells (ER-OV-01 and -06A) E Tunnel Ponds E Tunnel Out-flow Off-Site Springs Water Supply (Last Trails Ranch)
Tritium in Onsite Monitoring Wells with Histories of Elevated Concentrations
Biota Monitoring Game Birds Big Game (opportunistic sampling – e.g. road kills) Rabbits
Direct Radiation Monitoring Thermoluminescent Dosimeters
ETLD Monitoring Locations Area 3 RWMS Area 5 RWMS
Estimated Annual Exposures Locations With at Least 10-Year Histories
Calendar Year 2010 Radiological Dose to a Person Breathing Air on the NNSS (Gate 510) and Eating 20 Jackrabbits from near the Sedan Crater
Conclusions • Concentrations of radionuclides from legacy contamination show decreasing trends primarily due to immobilization, dilution, and physical decay. • On-site operations involving radioactive materials are evaluated for air emissions. • Current pathways for radionuclides to off-site public are air and game animals (no current pathway for groundwater or direct radiation). • Concentrations of radionuclides measured in air at on-site compliance stations and in water at on and off-site environmental monitoring locations are much less than limits for exposure to the public.