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Home My WebLink AboutDRC-2010-003386 - 0901a0688018eec6DENISO MINES May 24, 2010 Denison Mines (USA) Corp. 1050 17th street. Suite 950 Denver, CO 80265 USA Tel: 303 628-7798 Fax: 303 389-4125 www.denisonmlnes.com VIA PDF AND FEDERAL EXPRESS Mr. Dane L. Finerfrock Co-Executive Secretary Utah Water Quality Board State of Utah Department of Environmental Quality 168 North 1950 West P.O. Box 144850 Salt Lake City, UT 84114-4850 Dear Mr. Finerfrock: Re: DUSA 4**^ Quarter, 2009 (February 28, 2010) Groundwater Monitoring Report: Notice of Violation and Compliance Order, Docket No. UGW10-03 This letter is in response to the foregoing Notice of Violation (the "Notice") dated April 20, 2010, whiiDh Denison Mines (USA) Corp. ("DUSA") received on April 23, 2010. The Notice lists eight violations (the "Violations") of the White Mesa Mill's (the "Mill's") Ground Water Quality Discharge Permit No. UGW370004 (the "Permit"), based on a review of the Mill's Groundwater Monitoring Report for the 4'^ Quarter of 2009. Pursuant to Utah Code Annotated 19-5-111 (1953 as amended), this letter describes: a) the root cause of the noncompliance; b) steps that have been or will be taken to correct the violation; c) date when compliance was or wili be regained; and d) steps taken or to be taken to prevent reoccurrence of the noncompliance. DUSA responds as follows: 1. Part I.F.1 of the Permit for failing to report all well monitoring and samples collected, including a result for TDS In wells MW-31 and MW-32 In the 4'" Quarter 2009 Report, for the October 2009 monitoring event. a) Root Cause of the Noncompliance TDS was sampled and analyzed in MW-31 and MW-32 for the 4* quarter of 2009, but the samples for TDS in those wells were received at the laboratory beyond their holding times. TDS was re-sampled in those wells during the 4* quarter 2009 and the sample results were the subject of a separate analytical report. Denver Environmentai Staff was not aware of this re-sampling and did not notice the omission of these TDS results when preparing the 4*^ Quarter 2009 Report, because Denison had not at the time instituted computer checks for completeness on its analytical results. b) Steps That Have Been Taken to Correct the Violation The following steps have been taken to correct the violation: (i) When informed by Division of Radiation Control ("DRC") staff of this omission during the week of March 29, 2010, Denison submitted to the Executive Secretary the analytical results for TDS in MW-31 and MW-32 under cover of an email dated April 2, 2010; and (ii) Denison has instituted computer checks for analytical data completeness, commencing with the 1^' Quarter 2010 Groundwater Monitoring Report. d) Date When Compliance Was or Will be Regained Compliance was regained on April 2, 2010 with the submission of the analytical results to the Executive Secretary e) Steps Taken to Prevent Reoccurrence of the Noncompliance Denison has instituted computer checks for analytical data completeness, commencing with the 1^* Quarter of 2010. 2. Part I.F.1 of the Permit and Section 4.3.3 of the DUSA QAP for failing to report all well monitoring and samples collected, Including a result for TDS in field duplicate MW-65 In the 4"^ Quarter 2009 Report, for the October 2009 monitoring event. a) Root Cause of the Noncompliance TDS was sampled and analyzed in field duplicate MW-65 for the 4*^ quarter of 2009, but the sample for TDS was received at the laboratory beyond its holding time. TDS was re-sampled in that well during the 4* quarter 2009 and the results were the subject of a separate analytical repori. Denver Environmental Staff was not aware of this re-sampling and did not notice the omission of these TDS results when preparing the 4*"^ Quarter 2009 Report, because Denison had not at the time instituted computer checks for completeness on its analytical results. b) Steps That Have Been Taken to Correct the Violation The following steps have been taken to correct the violation: (i) When informed by DRC staff of this omission during the week of March 29, 2010, Denison submitted to the Executive Secretary the analytical results for TDS in field duplicate MW-65 under cover of an email dated April 2, 2010; and (ii) Denison has instituted computer checks for analytical data completeness, commencing with the 1^' Quarter 2010 Groundwater Monitoring Report. c) Date When Compliance Was or Will be Regained Compliance was regained on April 2, 2010 with the submission of the analytical results to the Executive Secretary d) Steps Taken to Prevent Reoccurrence of the Noncompliance Denison has instituted computer checks for analytical data completeness, commencing with the 1®' Quarter of 2010. 3. Part I.E.I (a) of the Permit and Section 6.2.7(d)(v) of the DUSA QAP for failing to achieve stable turbidity conditions before collecting groundwater samples in 12 wells during the October, November, and December, 2009 monitoring events. a) Root Cause of the Noncompliance Data indicate that it may not be feasible to achieve both a turbidity level less than 5 NTU and a stabilized turbidity between any two measurements within 10% RPD in every well. Discussions are underway with DRC to address the issue that it may not be appropriate or feasible to achieve consistent turbidity levels DENISOl MINES of 5 NTU in the Mill's groundwater program wells under the current evacuation scheme, and that other well purging approaches, such as micro-purging, may be more appropriate. b) Steps That Have Been Taken to Correct the Violation A letter report addressing modification of monitoring methods relative to turbidity issues, submitted by DUSA to DRC is currently under review. c) Date When Compliance Was or Will be Regained Compliance will be achieved when monitoring methods relative to turbidity are modified to address Mill site conditions. d) Steps Taken to Prevent Reoccurrence of the Noncompliance See paragraph c) above. 4. Part I.E.I (a) of the Permit and Section 6.2.7(d)(v) of the DUSA QAP for failing to achieve stable redox potential (Eh) conditions before collecting groundwater samples in 5 wells during the October and November, 2009 monitoring events. a) Root Cause of the Noncompliance The calculations used by Denver Environmental Staff were incorrect, and, as a result the failures to achieve stable redox potential conditions were not apparent when preparing the 4"^ Quarter 2009 Groundwater Monitoring Report. The calculation has been computer automated, verified and corrected as of the 1^' Quarter 2010 Groundwater Monitoring Report. With respect to the actual failure to achieve stable redox potential in the wells, data indicate that it may not be feasible to achieve stabilized parameters, including redox, between any two measurements within 10% RPD in every well. Discussions are underway with DRC to address the issue that it may not be appropriate or feasible to achieve stabilization of every parameter in every well under the current evacuation scheme, and that other well purging approaches, such as micro-purging, may be more appropriate. b) Steps That Have Been Taken to Correct the Violation A letter report addressing modification of monitoring methods relative to parameter stability issues, submitted by DUSA to DRC is currently under review. c) Date When Compliance Was or Will be Regained Compliance will be achieved when monitoring methods are modified to address Mill site conditions. d) Steps Taken to Prevent Reoccurrence of the Noncompliance See paragraphs a) and c) above. 5. Part I.E.I (a) of the Permit and Section 6.2.7(d)(v) of the DUSA QAP for failing to excavate two casing volumes before collecting groundwater samples in 17 wells during the 4 Quarter (October) 2009 Monitoring event. a) Root Cause of the Noncompliance As stated in the 4"^ Quarter 2009 Groundwater Monitoring Report, prior to November 17, 2009, sampling personnel believed that they had the option either to pump each well to two casing volumes or to pump the well until field parameters were stabilized. Further, they believed they had the verbal approval of the DRC representative who has witnessed the field sampling program, to determine how long each well would require to be pumped to two casing volumes, and to pump only to 120 minutes on any well that would require longer than this interval of time. DUSA received a Notice of Violation dated November 17, 2009 in which DRC identified that Mill staff were not following the QAP requirement to evacuate two casing volumes and to achieve stable parameters. DENISO MINES b) Steps That Have Been Taken to Correct the Violation As stated in the 4* Quarter 2009 Groundwater Monitoring Report, on receipt of the November 17, 2009 NOV, sampling personnel were instructed to evacuate two casing volumes and determine well parameter stabilization. They were also instructed that a perceived verbal approval from DRC personnel will not replace the written requirernents of the Permit and/or the QAP. c) Date When Compliance Was or Will be Regained As stated in the 4"^ Quarter 2009 Groundwater Monitoring Report, the first two months of the 4* Quarter 2009 sampling program were already under way at the time sampling personnel received these instrucfions. As a result the October and November 2009 samples were collected under an incorrect understanding of the procedure. Compliance was achieved upon filing the 1^' Quarter 2010 Groundwater Monitoring Report. d) Steps Taken to Prevent Reoccurrence of the Noncompliance See paragraph b) above. 6. Part I.E.1(a) of the Permit and Section 3.1 of the DUSA QAP for failing to use the correct formula in 39 instances to determine RPD for the duplicates of the October, November, and December, 2009 monitoring events. a) Root Cause of the Noncompliance The RPD calculation results in the 4* Quarter 2009 and previous groundwater and chloroform reports have been in error, as brought to the attention of DUSA by DRC in their letter of February 17, 2010 and close out telephone call of April 5, 2010. b) Steps That Have Been Taken to Correct the Violation The RPD calculation has been computer automated, verified and corrected as of the 1®' Quarter 2010 Groundwater Monitoring Report. c) Date When Compliance Was or Will be Regained Compliance has been achieved as of May 19, 2010, the date of filing the 1^' Quarter 2010 Groundwater Monitoring Report. d) Steps Taken to Prevent Reoccurrence of the Noncompliance See paragraph b) above. 7. Part I.F.1 (e) of the Permit and Section 9.1.4(a) of the DUSA QAP for failure to fully and completely disclose all non-conformance with the approved QAP for the October, 2009 sampling event with respect to a RPD in excess of 20% for ammonia (as nitrogen) in well MW- 22 and blind duplicate sample MW-70. a) Root Cause of the Noncompliance As a result of DUSA using the incorrect manner of calculating RPD referred to in Violation 6 above, the RPD in excess of 20% for ammonia (as nitrogen) in well MW-22 and blind duplicate sample MW-70 was not apparent, and therefore not disclosed. b) Steps That Have Been Taken to Correct the Violation The RPD calculation has been computer automated, verified and corrected as of the 1^' Quarter 2010 Groundwater Monitoring Report, so that this type of violation will not occur in the future. c) Date When Compliance Was or Will be Regained DENISO MINES Compliance has been achieved as of May 19, 2010, the date of filing the 1^' Quarter 2010 Groundwater Monitoring Report. d) Steps Taken to Prevent Reoccurrence of the Noncompliance See paragraph b) above. 8. Part I.E.I (a) of the Permit and Section 11 of the DUSA QAP for failing to list in a summary table analytes wells that were subject to accelerated monitoring pursuant to Parts I.G.1 and 2 of the Permit, including uranium (MW-14, MW-15, and MW-17) and thallium (MW-18). a) Root Cause of the Noncompliance Denver Environmental Staff inadvertently omitted these analytes from the summary table of analytes that are subject to accelerated monitoring. When preparing the 4"" Quarter 2009 Report, Denison had not at the time instituted computer checks for determining accelerated monitoring status. b) Steps That Have Been Taken to Correct the Violation Denison has instituted computer checks for determining accelerated monitoring status for analytes, commencing with the 1 ^' Quarter 2010 Groundwater Monitoring Report. c) Date When Compliance Was or Wiil be Regained Compliance was regained on May 19, 2010 with the filing of the 1^' Quarter 2010 Groundwater Monitoring Report. d) Steps Taken to Prevent Reoccurrence of the Noncompliance Denison has instituted computer checks for determining accelerated monitoring status, commencing with the 1^'Quarter of 2010. If you have any questions or require any further information, please contact the undersigned. Yours very truly. DENISON MINES (USA) CORP. Jo Ann Tischler Director, Compliance and Permitting cc: David C. Frydenlund Ron F. Hochstein Harold R. Roberts David E. Turk DENISO MINES