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HomeMy WebLinkAbout20100632 Esther Gesick To: jeana.burton@mac.com Subject: FW: Protect Weld County and Colorado from uranium contamination Attachments: LEUraniumEmail.doc Please see the attached response. Esther E. Gesick Deputy Clerk to the Board Weld County, Colorado 915 10th Street Greeley, CO 80631 (970)336-7215 X4226 (970)352-0242 (fax) Original Message From: William Garcia Sent: Wednesday, March 24, 2010 9:05 AM To: Esther Gesick Subject: FW: Protect Weld County and Colorado from uranium contamination Original Message From: Jeana Burton [mailto:jeana.burton@mac.com] Sent: Tuesday, March 23, 2010 10:40 PM To: William Garcia Subject: Protect Weld County and Colorado from uranium contamination Dear Mr. Garcia, I am writing to you because I am very concerned about the potentially severe impacts the proposed uranium mine near Nunn, Colorado will have on our land, water, and health. I'm particularly concerned about the impact this mine will have on the economies of Weld and Larimer counties. None of us - rural farmer or suburban homeowner - can afford to have our groundwater contaminated, especially by a foreign company who will take their profits home, then very likely declare bankruptcy. Once Powertech has dissolved their current corporate identity and terminated any liability they once might have had, they will leave Colorado and America holding the clean-up bill. Powertech and other mining corporations have been unable to prove that they won't contaminate our aquifer, which they want to use to extract uranium. It is very likely they will contaminate our aquifer and then pull stakes. I have pasted a summary below showing that the best case scenario for Weld county and Colorado, in the wake of this contamination. Even if it is possible - with a huge influx of funds from the federal Environmental Protection Agency - to restore the Powertech contaminated aquifer to pre-mining quality, it will take more clean water for this "flushing" than Coloradoans can afford to dedicate to this purpose. e ; ro 2010-0632 3—a9— /O According to Nigbor and Engelman, who are both industry experts - not environmentalists - it might take "a water volume of more than 20 times the porevolume of the leaching zone. . .and still several parameters [would] not reach background levels [Nigbor1982] [Engelmann1982] ." I ask that you do everything in your power to stop this project and to protect Weld and Larimer county residents. It's our water. It's our future. Thank You, Jeana Burton Fort Collins resident and Weld County agriculture supporter Sources summarized by http://www.wise-uranium.org/uisl.html#RECLAMPR0J: <http://console.mxlogic.com/redir/?bXab1EVhhKrppjvKesjdw0z4GunrzI9dGY01NK13- 1M60Ig4wG83om1oo0x8TvHTv7cLnjKyrKr4v56YgrzeIOkHJKndFECzBVw5yCUgembLK8I6TPhOr2QqP- QPhOOLDE6y0iGT2poQgr10Qg21jWNR2FEwtzlkQgdN54CRjh1gI9WHa6PBm1KvxYYmf5k3g9J4S00C_ssyyrB6hE> Engelmann,W H; Phillips,P E; Tweeton,D R; Loest,K W;Nigbor,M T: Restoration of Groundwater Quality Following Pilot-Scale Acidic In-Situ Uranium Leaching at Nine- Mile Lake Site Near Casper, Wyoming. In: Society of Petroleum Engineers Journal, June 1982, p.382-398 Nigbor,Michael T; Engelmann,William H; Tweeton,Daryl R: Case History of a Pilot-Scale Acidic In Situ Uranium Leaching Experiment. United States Department of the Interior, Bureau of Mines Report of Investigations RI-8652, Washington D.C. , 1982, 81 p. Reclamation Concepts After In-Situ Leaching After termination of an in-situ leaching operation, the waste slurries produced must be safely disposed, and the aquifer, contaminated from the leaching activities, must be restored. Groundwater restoration is a very tedious process that is not yet fully understood. So far, it is not possible to restore groundwater quality to previous conditions. The best results have been obtained with the following treatment scheme, consisting of a series of different steps [Schmidt1989], [Catchpole1995] : * Phase 1: Pumping of contaminated water: the injection of the leaching solution is stopped and the contaminated liquid is pumped from the leaching zone. Subsequently, clean groundwater flows in from outside of the leaching zone. * Phase 2: as 1, but with treatment of the pumped liquid (by reverse osmosis) and re- injection into the former leaching zone. This scheme results in circulation of the liquid. * Phase 3: as 2, with the addition of a reducing chemical (for example hydrogen sulfide H25 or sodium sulfide Na25) . This causes the chemical precipitation and thus immobilization of major contaminants. * Phase 4: Circulation of the liquid by pumping and re- injection, to obtain uniform conditions in the whole former leaching zone. But, even with this treatment scheme, various problems remain unresolved: * Contaminants, that are mobile under chemically reducing conditions, such as radium, cannot be controlled, 2 'L 1619 * if the chemically reducing conditions are later disturbed for any reasons, the precipitated contaminants are re-mobilized, * the restoration process takes very long periods of time, * not all parameters can be lowered appropriately. Most restoration experiments reported refer to the alkaline leaching scheme, since this scheme is the only one used in Western world commercial in-situ operations. Therefore, nearly no experience exists with groundwater restoration after acid in- situ leaching, the scheme that was applied in most instances in Eastern Europe. The only Western in-situ leaching site restored after sulfuric acid leaching so far, is the small pilot scale facility Nine Mile Lake near Casper, Wyoming (USA). The results can therefore not simply be transferred to production scale facilities. The restoration scheme applied included the first two steps mentioned above. It turned out that a water volume of more than 20 times the porevolume of the leaching zone had to be pumped, and still several parameters did not reach background levels. Moreover, the restoration required about the same time as used for the leaching period [Nigbor1982] [Engelmann1982] . 3 Hello