2001-02-21_REVISION - M1988112 - Laserfiche WebLink

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~, iii iiiiiiiiiiiuiii ~,, STATE OF COLORADO DIVISION OF MINERALS AND GEOLOGY Department of Natural Resources 1313 Sherman 51., Room 215 Denver, Colorado 80:03 Phone: X3031 866-3567 FAY: (3031 83?-8106 February 21, 2001 DIVISION O F MINERALS GEOLOGY RECLAMA710N MI NING•SAFE 7Y Mr Dave Long col onoens Battle Mountain Resources Inc Greg E. Watcher PO Box 310 Executive Director San Luis CO 81152 Michael 8. Long Dlmsion Director Re: Groundwater Sample Collection Procedures, San Luis Project, Dear Mr. Long: Your latest letter, dated February 14, 2001, states that attempts were made to collect water samples from the SF-1 and SF-1R monitoring wells but, due to insufficient grouhdwater supply, representative samples could not be collected and, because of the slow yield of groundwater recovery, BMRI feels the wells are outside the groundwater sampling criteria co>atained in TR- 06. There are provisions in TR-06 dealing with low volume wells. Section 2.2.7 (Well Evacuation) states, in part, that "wells with very low recovery rates will be pumped or bailed to dryness and allowed to recover prior to sampling. If this happens, it will be noted on the Field Data Collection Sheet that the evacuation of a minimum three casing volumes criteriop was not met for this well. If possible, sampling should take place within 2.4 hours after well e>acuation." If the well takes longer than 24 hours to produce sufficient quantities of water for sampling it, also, should be noted. Section 2.2.4 (Groundwater Sampling) of TR-06 states that BMRI sampling personnel may need [o modify procedures as sampling progresses in the event the wells and their abila[y to yield water varies due to the hydrogeologic properties of the aquifer at any given location. Simples obtained from the monitoring wells should represent water quality in the aquifer. Necessaty deviations from the general protocol procedures should be fully documented on the Field Data Collection Form. If general groundwater collection procedures have been modified by the s811mpling personnel, the new method should be described in detail and reported to the Division. I believe TR-06 sample collection protocol provides sufficient methods to deal with the low volume monitoring wells. If you have any questions, please give me a call.