Loading...
HomeMy WebLinkAboutDRC-2013-001647 - 0901a0688035cbadENERGYFUELS March 14,2013 Sent VIA OVERNIGHT DELIVERY Mr. Rusty Lundberg Division of Radiation Control Utah Department of Environmental Quality 195 North 1950 West P.O. Box 144850 Salt Lake City, UT 84114-4820 Energy Fuels Resources (USA) Inc. 225 Union Blvd. Suite 600 Lakewood, CO, US, 80228 303 974 2140 www.energyfuels.com Re: Transmittal of Plan and Time Schedule under Utah Ground Water Discharge Permit UGW370004 Part I.G.4 (d) White Mesa Mill (the "Mill") Dear Mr. Lundberg: DRC-2013.00164? This letter transmits Energy Fuels Resources (USA) Inc.'s ("EFRI's") Plan and Time Schedule pursuant to State of Utah Groundwater Discharge Permit UGW370004 (the "Permit") Part LG.4(d) for Violations of Part LG.2 of the Permit. Part I.G.2 of the Permit provides that out-of-compliance ("OOC") status exists when the concentration of a pollutant in two consecutive samples from a compliance monitoring point exceeds a groundwater compliance limit ("GWCL"). On February 15, 2013, EFRI submitted a letter to the Director under Part LG.l(a) of the Permit providing notice that the concentrations of specific constituents in groundwater monitoring wells at the Mill exceeded their respective GWCL's for the 4th quarter of 2012 and indicating which of those constituents had two consecutive exceedances during that quarter. This Plan and Time Schedule addresses violations of Part I.G.2 of the Permit for the 4th quarter of 2012. Please contact me if you have any questions or require any further information. Yours very truly, ENERGY FUELS RESOURCES (USA) INC. ^o Ann Tischler Director, Compliance and Licensing cc: David C. Frydenlund Harold R. Roberts David E. Turk Katherine A. Weinel WHITE MESA MILL State of Utah Ground Water Discharge Permit UGW370004 Plan and Time Schedule Under Part I.G.4 (d) For Violation of Part I.G.2 for a Constituent in the Fourth Quarter of 2012 Energy Fuels Resources (USA) Inc. 225 Union Boulevard, Suite 600 Lakewood, CO 80228 March 14, 2013 1. INTRODUCTION Energy Fuels Resources (USA) Inc. ("EFRI") operates the White Mesa Uranium Mill (the "Mill"), located near Blanding Utah, under State of Utah Ground Water Discharge Permit UGW370004 (the "Permit"). This is the plan and time schedule (the "Plan") required under Part LG.4(c) of the Permit relating to violations of Part I.G.2 of the Permit for the 4th quarter of 2012. Part I.G.2 of the Permit provides that out-of-compliance status exists when the concentration of a pollutant in two consecutive samples from a compliance monitoring point exceeds a groundwater compliance limit ("GWCL") in Table 2 ofthe Permit. The Permit was originally issued in March, 2005, at which time GWCLs were set on an interim basis, based on fractions of State Ground Water Quality Standards or the equivalent, without reference to natural background at the Mill site. The Permit also required that EFRI prepare a background groundwater quality report to evaluate all historic data for the purposes of establishing background groundwater quality at the site and developing GWCLs under the Permit. As required by then Part LH.3 of the Permit, EFRI submitted the following to the Director of the Utah Division of Radiation Control ("DRC") (the Director was formerly known as the Executive Secretary of the Utah Radiation Control Board and the Co-Executive Secretary of the State of Utah Water Quality Board): • A Revised Background Groundwater Quality Report: Existing Wells For Denison Mines (USA) Corp.'s Mill Site, San Juan County, Utah, October 2007, prepared by INTERA, Inc. (the "Existing Wells Background Report"); • A Revised Addendum: ~ Evaluation of Available Pre-Operational and Regional Background Data, Background Groundwater Quality Report: Existing Wells For Denison Mines (USA) Corp.'s Mill Site, San Juan County, Utah, November 16, 2007, prepared by INTERA, Inc. (the "Regional Background Report"); and • A Revised Addendum: - Background Groundwater Quality Report: New Wells For Denison Mines (USA) Corp. 's Mill Site, San Juan County, Utah, April 30,2008, prepared by INTERA, Inc. (the "New Wells Background Report, and together with the Existing Wells Background Report and the Regional Background Report, the "Background Reports"). Based on a review of the Background Reports and other information and analyses the Director re-opened the Permit and modified the GWCLs to be equal to the mean concentration plus two standard deviations or the equivalent. The modified GWCLs became effective on January 20, 2010. The Director issued a Notice of Violation and Compliance Order, Docket No.UGWll-02 (the "Notice of Violation"), dated May 9, 2011, based on DRC's findings from the review of the Mill's first, second, and third quarter 2010 Groundwater Monitoring Reports. The Notice cited five violations of the GWDP, including a violation under the Utah Water Quality Act (UC 19-5- 107) and Part LCI of the GWDP, in that six contaminants have exceeded their respective GWCLs, as defined in Table 2 of the GWDP, for two consecutive sampling events. Section E.4 of the Notice ordered EFRI to prepare and submit, within 30 calendar days of receipt of the Notice, a written plan and time schedule for Director approval to fully comply with the requirements of Part LG.4(c) of the GWDP. In response to the Notice, EFRI submitted the Initial Plan and Time Schedule ("Initial Plan and Time Schedule") to address constituents that exceeded their respective GWCLs for two consecutive sampling events in the 2"^, 3^** and 4* quarters of 2010 and the 1'* quarter of 2011. The Initial Plan and Time Schedule was submitted June 13, 2011. Subsequent to the Initial Plan and Time Schedule, EFRI submitted a Plan and Time Schedule for the 2""* Quarter 2011 ("Q2 2011 Plan and Schedule") to address constituents that exceeded their respective GWCLs for two consecutive sampling events in the 2^^ quarter 2011. The Q2 2011 Plan and Schedule was submitted on September 7, 2011. In the 1^* quarter 2012, TDS in MW-31 was identified as exceeding its respective GWCL for two consecutive sampling events. EFRI requested that no additional plan and time schedule be prepared and that this exceedance be addressed in conjunction with the sulfate exceedances as described in the June 13, 2011 Initial Plan and Time Schedule. DRC agreed with this request in correspondence dated August 1, 2012. Pursuant to the Initial Plan and Schedule and the Q2 2011 Plan and Schedule, EFRI submitted a Source Assessment Report ("SAR") to DRC on October 10, 2012. The SAR covered the constituents in violation of Part I.G.2 of the GWDP that were identified in the Initial Plan and Time Schedule and in the Q2 2011 Plan and Schedule. On November 15, 2012 EFRI submitted a notice (the "3rd Quarter 2012 Exceedance Notice") to the Executive Secretary under Part I.G.I (a) of the Permit providing notice that the concentrations of specific constituents in the monitoring wells at the Mill exceeded their respective GWCLs for the 3'^ quarter of 2012 and indicating which of those constituents had two consecutive exceedances as of that quarter. A Plan and Time Schedule for 3''' Quarter 2012 ("Q3 2012 Plan and Time Schedule") covers the constituent that was identified as being in violation Part I.G.2 of the Permit in the 3^^ Quarter 2012. The Q3 2012 Plan and Time Schedule was submitted on December 13, 2012. The Q3 2012 Plan and Time Schedule was approved by DRC in correspondence dated February 4,2013. On February 15, 2013 EFRI submitted a notice (the "4th Quarter 2012 Exceedance Notice") to the Executive Secretary under Part I.G.I (a) of the Permit providing notice that the concentrations of specific constituents in the monitoring wells at the Mill exceeded their respective GWCLs for the 4* quarter of 2012 and indicating which of those constituents had two consecutive exceedances as of that quarter. This Plan covers the constituent that was identified as being in violation Part I.G.2 of the Permit in the 4* Quarter 2012 Exceedance Notice dated February 15, 2013. 2. CONSTITUENT AND WELL SUBJECT TO THIS PLAN The following Q4 2012 Consecutive Exceedance has been identified as being in out-of- compliance status under Part I.G.2 of the Permit in the 4* Quarter 2012 Exceedance Notice: Table 1 Constituent and Well Subject to this Plan Constituent Monitoring Event POC Well GWCL Result Selenium 3rd Qtr 2012 (7/9/12) 4th Qtr, 2012 (11/6/12) MW-31 71 ug/L 74 ug/L 76.9 ug/L It should be noted that the Notice of Violation and the Exceedance Notices to date identify a number of wells with consecutive exceedances of nitrate + nitrite and/or chloride, chloroform and dichloromethane, and pH (less than the respective GWCLs for pH in a number of wells). However, none of those constituents are included in the SAR which was submitted October 10, 2012, for the reasons stated in the Notice of Violation. That is, chloroform and dichloromethane are associated with the existing chloroform plume at the Mill, as contemplated in the August 23, 1999 DRC Notice of Violation and Groundwater Corrective Action Order. Nitrate + nitrite and chloride are associated with the nitrate/chloride plume, addressed by the Draft Corrective Action Plan, dated May 2012. With respect to pH, a separate Plan and Time Schedule submitted April 13, 2012, was accepted by DRC as specified in a Stipulated Consent Agreement dated July 12, 2012. pH was addressed in a separate report submitted under separate cover dated November 9, 2012 as specified in the July 12, 2012, Stipulated Consent Agreement. The Stipulated Consent Agreement dated July 12, 2012 also specified the completion of the Pyrite Investigation Report to further study the decreasing pH trends noted across the Mill site. The Pyrite Investigation Report was submitted on December 7, 2012. 3. CATEGORIES FOR ANALYSIS Previously EFRI has categorized wells and constituents in several categories as follows: Constituents Potentially Impacted by Decreasing pH Trends Across the Site Newly Installed Wells with Interim GWCLs Constituents in Wells with Previously Identified Rising Trends Pumping Wells Other Constituents Selenium in MW-31 falls within the first category; constituents potentially impacted by decreasing pH trends across the site. Assessment of selenium in MW-31 will follow the process previously used for other wells in this category. 3.1 Constituents Potentially Impacted by Decreasing pH Trends Across the Site EFRI has observed a decreasing trend in pH in a number of monitoring wells across the Mill site. See the discussions in the SAR dated October 10, 2012, the pH Report dated November 9, 2012 and the Pyrite Investigation Report dated December 7, 2012. The pH Report specifically noted that wells MW-03, MW-03A, MW-11, MW-12, MW-14, MW-15, MW-17, MW-18, MW-22, MW-24, MW-25, MW-30, MW-32, and MW-37 showed significantiy decreasing trends in pH. It was also noted that, while not statistically significant, on a review of pH time plots in all wells, there appears to be a general decreasing trend in pH in all wells, including MW-31. The mobility in groundwater of selenium is sensitive to decreases in pH. 4. PLAN 4.1. General This Plan is a plan and time schedule for assessment of the source, extent and potential dispersion of the contamination, and an evaluation of potential remedial action to restore and maintain groundwater quality to assure that Permit limits will not be exceeded at the compliance monitoring point and that, to the extent applicable, discharge minimization technology and best available technology will be reestablished. Given the analyses in the Background Reports and the recent analyses in the SAR and pH report and other recent information relating to the Chloroform and Nitrate/Chloride investigations at the site, EFRI believes that the exceedance of selenium in MW-31 is likely due to background influences (including a natural decreasing trend in pH across the site, rising water levels in some wells and other factors), disruption of the aquifer by pumping and/or the geochemical influences of the existing chloroform and nitrate/chloride plumes. Therefore, the first step in the analysis will be to perform an assessment of the potential source of the exceedance to determine whether the exceedance is due to background influences or Mill activities. If the exceedance is determined to be due to background influences then it will not be necessary to perform any further evaluations on the extent and potential dispersion of the contamination or to perform an evaluation of potential remedial actions. Monitoring will continue, and where appropriate a revised GWCL will be proposed to reflect changes in background conditions at the site. If revising the GWCL is appropriate, the process will include a statistical analysis of selenium data from MW-31 using the methods described in the Existing Wells Background Report (INTERA, 2007a) and the State of Utah Department of Environmental Quality approved Flowsheet ("the Flowsheet"). However, if the exceedance is determined to be caused by Mill activities, then EFRI will proceed to the next step and will consider the extent and potential dispersion of the contamination, and will perform an evaluation of potential remedial actions to restore and maintain groundwater quality to insure that Permit limits will not be exceeded at the compliance monitoring point. This two-step approach is necessary, because, in light of the varied background conditions at the site and previously identified background trends, it can't be assumed that consecutive exceedances of a constituent in a well represents contamination that has been introduced to the groundwater. It is first necessary to establish whether or not the exceedances represent background influences. 4.2. Approach for Analvsis As mentioned above, EFRI has observed a decreasing trend in pH in a number of monitoring wells across the Mill site. The mobility in groundwater of selenium is sensitive to decreases in pH. The primary focus of the source assessment for selenium in MW-31 will be two-fold. First, EFRI will determine whether or not there is any new information that would suggest that the previous analyses conducted in the Existing Wells Background Report, the SAR, or the pH Report has changed since the date of that Report. This analysis will include the following: (i) A geochemical analysis that will evaluate the behavior of the constituents in MW-31 to determine if there are any changes in the behavior of indicator constituents, such as Chloride, Sulfate, Fluoride and Uranium since the date of the Existing Wells Background Report, the SAR, and the pH Report, that may suggest a change in the behavior of that well since the date of that Report; (ii) If necessary, a mass balance analysis that will evaluate the observed concentrations in light of the concentrations in Mill tailings and the presence or absence of any mounding at the location of the well in question; and Second, a pH analysis will be performed for selenium that will: (iii) Review the behavior of pH in the well to determine if there has been a significant decrease in pH in the well; and (iv) Analyze the expected impact from any such decrease in pH on the concentration of selenium, based on currently available information. The foregoing analyses (both steps) will be included in the Source Assessment Report. If no significant changes are identified that would suggest that the previous analysis conducted in the Background Reports, the SAR and the pH Report, has changed other than what would be expected from decreasing trends in pH, then EFRI will propose changes to the GWCL for selenium in MW-31 wells to better reflect background concentrations at the site. If significant changes are identified that cannot be attributed to changes in pH or other natural phenomena, then EFRI will propose to the Director further analysis that may be required in order to identify the source and the extent and potential dispersion of the contamination, as well as potential remedial actions. 4.3. Expert Reports to be Prepared The results of the statistical analysis and, if appropriate, recalculation of the GWCL will be compiled as a SAR that will be submitted to DRC within 90 days of the approval of this plan. The SAR will detail the results of all of the analyses to be performed and the conclusions to be drawn from such analyses, including any proposed revisions to existing GWCLs. Specifically, the SAR will follow the format of the previously submitted SAR (October 10, 2012) and will include discussions, results and conclusions of the analysis and appendices containing the following: A geochemical analysis of selenium in MW-31 Comparison of calculated and measured TDS for samples with complete major ions Charge balance calculations Descriptive statistics Box plots to identify extreme outliers Histograms and Shapiro Wilk test for normality Regression or Mann Kendall trend analysis Proposed Revised GWCL for selenium in MW-31 A geochemical analysis of Indicator Parameters in MW-31 Descriptive Statistics Box plots to identify extreme outliers Histograms and Shapiro Wilk test for normality Regression and/or Mann Kendall trend analysis A pH analysis in MW-31 Descriptive Statistics Box plots to identify extreme outliers Histograms and Shapiro Wilk test for normality Regression and/or Mann Kendall trend analysis 5. TIME SCHEDULE The SAR will be submitted to the Director within 90 days after approval of this Plan. The SAR contemplated by this submission, may be combined with any subsequent SARs resulting from other Plans and Schedules for other out of compliance constituents, as necessary. 6. CONCLUSION Given the varied background groundwater quality at the site it cannot be assumed that consecutive exceedances of a constituent in a monitoring well means that contamination has been introduced to groundwater in that well. With respect to MW-31, preliminary analysis suggests that the Q4 2012 Consecutive Exceedance of selenium represents impacts due to a decreasing pH (not statistically significant).