PERMFILE122086 - Laserfiche WebLink

Home Browse Search

Also, trees that were greater than four inches in diameter had been dozed over, not cut down and removed as required. The ntix of topsoil and trees shoved into piles was clearl}~ in violation of road construction and erosion control requirements. Item 5: The package of information transmitted to me did not have Attachment 5. Therefore, 1 have not had an opportunity to review the water level data in this Attachment. However, BLM's response raises several questions. First, what is "enough continuous operation"? What levels of pumping were assumed in the first place, and how does Ote lower volume of pumping fit in the context of the Test Mine Plan. Second, I would anticipate that the confined aquifers (A-Groove, B-Groove and Dissolution Surface) would respond to changes in potentiomelric head pressures well before water qualiq• changes. Hopefull}•, the data will be continuous with hourly averages rather than periodic since it will be more difficult to interpret the data. I look forward to receipt of Attachment 5 as soon as possible. Item 6: The purpose of the 2,000 mgJl water quality requirement vvas ostensibly to establish a threshold which would be used to indicate the possibility of Lower Aquifer water being drawn into the Upper Aquifer. COA t/8 was a mandatory perl'onnance condition, i.e., "shall be discontinued." The bicarb values in this well have increased substantiall}• since pumping has been initiated, as has llte overall TDS. Based on a comparison between the Itigltest monitored value (2,906 mg/I) and the water quality baseline (793 mg/I), bicarb concentrations have increased up l0 3.6 times the baseline value. Tltis is a significant increase and indicative of drarttiatic changes in water quality in this well. Chloride experienced a maximum five-fold increase over the baseline value, and TDS incurred a maximum 1.69 increase over the baseline value. Further, the ratios between the I»glt bicarb/I'DS/cliloride parameters are not consistent. These collective changes in concentrations either indicate errors in sampling and anal}•sis, in which case HLM should have shut down the pumping and conducted its own independent sampling in order to obtain a realistic picture of water quality, or the Ouauations arc so significant as to indicate some intrusion of another water source, either the Lower Aquifer or rele<~scd drilling fluids or return product. In a recent letter to Rio Blanco County (3/8/99), American Soda acknowledged flaws in its data: "American Soda acknowledges that some of the data appear to be anomalous and tltc reasons for the anomalies arc unknown. American Soda believes that the regional data should be given careful consideration in evaluating the existing qualit}' of groundwater." This acknowledgment supports tltc need (or BLM to obtain a vvatcr quality baseline for the proposed commercial mining area prior to an}• further possible damage to the aquifers bcneatlt the mining area. Item 7: Anachment 7 does not provide dma for monitor well 20-8, unless it has been inappropriately designated Well 20-9. Further, the dates on Atmchmenl N7 arc not assigned to a specific year. Finally, it muss be assumed that the water level is in feet below ground surface, even though the graph does not so indicate. Please provide the most recent monitoring data, with appropriate definition, for Well 20-8 and 20-1. Item 8: The significantly high values for the 6-29-98 s~mplc of Monitoring Wcll 20-5 either indicates poor sampling or lab quality assurance, or it demonstrates an impact from mining or drilling operations. With discovery of such a Iugh value, did BLM immediately stop operations and request an explanation Cor the spike in the data. Further, the water qualip data, summarized bdotw, demonstrate high fluoride concentrations (four-told increase) which would be indicative of mixing between aquifers. What has BLM done to examine this issue. Further, bout the TDS and bicarb concentrations has shown substantial increases, which is inconsistent with the readings shown in the WRN water qualip data base.