HYDRO23688

• Permit No: M1999002
• IBM Index Class Name: Hydrology
• Doc Date: 9/22/2004
• Doc Name: Well 20-12 TDR Monitoring
• From: American Soda L.L.P.
• To: DMG
• Media Type: D
• Archive: No

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SODA, LLP
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Ed Cooley
Environmental Health and
Safety Manager
2717 County Road 215
Parachute, CO 81635
Direct Line [phone]
International Telephone [phone]
General Facsimile [phone]
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Sunday, September 19, 2004
Ken Phillips
U.S. Environmental Protection Agency
Region VIII
999 18'" Street, Suite 300
Mail Code 8ENF-UFO
Denver, Colorado 80202-2466
Oivisian of Minerals & Geology
Re: Well 20-12 TDR Monitoring
Dear Ken:
ENV.223.04
The EPA letter dated August 31, 2004 and received by American Soda on September 2, 2004
references the agencies concerns regarding the TDR cable monitoring results from Well 20-12
(C03858-04552) and points out the possibility of cavity collapses being the reason for the
results of TDR cable monitoring results rather than the effects of pressure of water in the tubing.
American Soda will address this possibility prior to resuming injection at the injection wells
surrounding the TDR monitoring well 20-12.
American Soda plans to continue monitoring the TDR Cable in this monitoring well and the
surface monitoring monuments adjacent to this location will be checked quarterly for the next
four quarters and then return to annual monitoring to help in correlating any subsidence that
may show on surface.
At this time we are evaluating other options to improve subsidence detection. We hope to
find a solution to this over the next 18 months and will continue to communicate with the EPA
on this matter.
Until we are able to verify that there has been no cavity collapse there will not be any
injection into wells 20-2, 20-3, 20-11, 20-12 & 20-14 which surround this TDR monitoring well.
Delivering a Crystal Clear Advantage
www.americanscda.com