Proposed Rule Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings 40 CFR 192

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1 Proposed Rule Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings 40 CFR 192 Environmental Protection Agency Office of Radiation and Indoor Air Washington, DC

2 Agenda Summary of the Proposed Rule. Uranium in-situ recovery: process and regulations. EPA proposed changes and rationale. Request for comment. 2

3 Summary of the Proposed Rule 40 CFR 192 Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings. Proposal published in the Federal Register on January 26, Currently, comment period open until April 27, Proposes to add a new subpart to address potential changes in groundwater at uranium in-situ recovery facilities. 3

4 What is In-Situ Recovery (ISR)? Fluids are injected into an orebearing aquifer to mobilize uranium. Extraction wells then collect the groundwater, which is processed at the surface to obtain the uranium. Fluids injected to mobilize uranium also mobilize minerals and metals like arsenic and lead, and change the chemistry of the aquifer from its original state. Groundwater from the altered aquifers could migrate over time and contaminate nearby ground water. 4

5 Location of Uranium ISR Facilities Map showing locations of principal sandstone-hosted uranium districts of the western US, and operating ISL mines (and three additional ones licensed and under construction as of 2014). Modified from EPA (1995) and Hall (2014). 5

6 Phases of ISR Operations 6

7 Licensing and Permitting for Uranium ISR Facility The Nuclear Regulatory Commission (NRC) has statutory authority through the Atomic Energy Act and the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA) to regulate uranium ISR facilities. In addition to obtaining an NRC license, uranium ISR facilities also must obtain the necessary permits from the appropriate federal, tribal, and state agencies. Under different environmental laws such as the Clean Water Act, the Safe Drinking Water Act (SDWA), and the Clean Air Act, EPA has statutory authority to regulate activities that may affect the environment. EPA permitting that is most relevant for uranium ISR facilities is related to underground injection of the leaching solution (i.e., the lixiviant) and liquid effluents, surface discharge of treated waters and industrial and construction stormwater, and air quality. Facilities must obtain under UIC regulations A permit for Industrial and Municipal Waste Disposal Wells (UIC Class I) A permit for Mining Wells (UIC Class III) An aquifer exemption (for aquifers of portion thereof, with TDS 10,000 mg/l) 7

8 Current 40 CFR 192 Regulations EPA regulations at 40 CFR 192 set standards to protect human health and the environment from hazards (radiological and non-radiological) associated with uranium and thorium ore processing. Standards for non-radiological hazards required by statute to be consistent with hazardous waste management. Standards are established under the legal authority of UMTRCA. Current standards are implemented by NRC and NRC agreement states. NRC has deemed in-situ recovery as underground milling and subject to UMTRCA and 40 CFR

9 Why is EPA Proposing Changes? ISR has become the predominant method of uranium extraction in the U.S. The current standards in 40 CFR 192 do not have explicit provisions that address in-situ recovery operations. Using the authority and general requirements in 40 CFR 192, NRC regulates ISR operations via site licenses. The proposed rule addresses the most significant hazards of uranium ISR by reducing the human health risk from exposure to radionuclides and protecting groundwater resources. UIC/SDWA aquifer exemption does not affect requirement to comply with UMTRCA standards. 9

10 What is EPA Proposing? EPA is proposing to add a new subpart that will establish pre-and post-operational monitoring and groundwater restoration requirements at ISR facilities. Once these standards are finalized, NRC and NRC agreement states will have the responsibility of implementing the standards. 10

11 What is EPA Proposing? (cont ) Requirements to characterize background groundwater chemistry The proposed rule describes how ISR facilities are to characterize groundwater chemistry before beginning uranium recovery operations. Requirements to meet restoration goals for 13 constituents The proposed rule would require compliance with whichever standard is most protective from the Safe Drinking Water Act (SDWA), the Resource Conservation and Recovery Act (RCRA), or UMTRCA. 11

12 What is EPA Proposing? (cont ) The 13 constituents arsenic barium cadmium chromium lead mercury selenium silver nitrate (as nitrogen) molybdenum radium total uranium gross alpha particle activity 12

13 What is EPA Proposing? (cont ) Performance standard If the water in the aquifer meets the groundwater standards before in-situ operations begin, it would have to be restored to meet them again after operations have stopped. If the constituent concentrations already exceed standards before operations begin, the operator would have to restore the groundwater chemistry to original, pre-operational concentrations. If background concentrations or groundwater protection standards cannot be achieved, operators can request an Alternate Concentration Limit (ACL), provided that they meet certain criteria and conditions. 13

14 What is EPA Proposing? (cont ) Requirements for Corrective Action At the time of licensing, the facility must develop and have approved a corrective action program. If an excursion is detected, the corrective action program must be implemented. Corrective action measures must be continued to the extent necessary to achieve and maintain compliance with the groundwater protection standards. 14

15 What is EPA Proposing? (cont ) Requirements for long-term stability monitoring Operators must monitor groundwater for 30 years after demonstrating that the groundwater chemistry has been restored and is stable; or May shorten the 30-year monitoring period if: Monitoring data show that groundwater has been restored to required levels, Statistical analyses shows that groundwater has remained stable for at least three consecutive years at a confidence level of 95 percent, and Geochemical modeling indicates that groundwater chemistry will remain stable and re-mobilization of targeted constituents is unlikely. 15

16 Examples of Monitoring Results Uranium Concentration (mg/l) Uranium Concentration (% Change from Mean) y = x R 2 = Date Years Concentration Mean Concentration Concentration Variability ±57% Trend Line Uranium Concentrations in Crow Butte Well PR-15 Deviation of Uranium Concentration from Mean with Variability Bounds (±1σ) 16

17 Summary In-situ recovery is now the predominant form of uranium extraction in the United States, but there are not explicit standards that govern the process. EPA s proposal establishes standards for the different phases of the in-situ recovery process. NRC and NRC Agreement States currently implement the standards at 40 CFR 192 and would implement the proposed standards once they become final. 17

18 Providing Comments on the Proposed Rule Stakeholders encouraged to submit comment. Public comment period closes on April 27, It may be extended. Public hearings are being planned. Time and location to be announced. Tribes interested in initiating consultation should contact EPA. Comments should be sent to the docket: EPA HQ OAR For questions, please contact: Ingrid Rosencrantz

19 Thank You!