Laserfiche WebLink
,-.. <br />Harding Lawson Associates <br />Match 5, 1996 ; <br />32640.19 ° <br />Ms. Christine E. Johnston <br />Mountain Coal Company <br />West Elk Mine <br />P.O.13ox 591 <br />Somerset, CO 81434 <br />Re: Borehole LRP~, Notice of Intent No. X-9212-04 <br />West Elk Mine, Colorado <br />Dear Ms. Johnston <br />Harding Lawson Associates (1-II.A) submits the following tesponu to the Division of Minerals and Geology <br />(DOMG), Department of Natural Resources internal memorandum dated January 23, 1996, regarding the Notice <br />of Intent (NOT) No. X-95-212-04, drillhole abandonntem report of boring LRP-4. According to the provisions of <br />the NOI, I12P~ was improperty completed; specifically, a bentonite seal was not installed between the sand filter <br />pack and cement groin annular plug. The purpose of the bentonite seal is to inhibit the migration of cement <br />slurry in the sand 51ter pack A possible effect of a thin cement slurry is infiltration into the pore spaces of the <br />sand filter pads which carld effectively inhibit migration of groundwater flow into the pizometer. <br />HI.A has reviewed the borehole abandonment report of I-RP~, and has noted that a bemonite seal was not toed <br />benveert the sand filter pads and the cement grout annular plug. In response to tite possible effect that a thin <br />cement slurry may infiltrate the pore spaces of the sand filter pads and inhibit the groundwater flaw to the <br />pimmaer, I-II.A submits the following water level readings for [,RPM. <br />LRP-4 1020/95 Water @ 13.70 tea <br />LRP-4 03N1/96 Water @ 12.73 feet <br />The can®t water level reading for I,RP-4 indicates a change of appmximatety one foot from October 20, 1995. <br />This change indicates that the groundwater flow imo pizometer LRPv3 has not been effected by the infiltmrion of <br />cement starry into the pore space of the sand filter pads. <br />If we can answer arty questions or provide more information, please do not hesitate to call us at (801) 363-1455. <br />~Y. <br />13ARDING LAWSON ASASSOCIATES <br />Loren A Jalben, P.G. <br />Proj E freer <br />Charlie C. Rettq P.E. <br />1'rinapal Engineer <br />LAJ/mg <br />Engineering antl t55 Scuth 300 West. Suite 703. Sall Lake Ciry, Utah BatOt Tele0hone: (80t) 363aa55 Facsimile: (9ot(363~4a76 <br />Environmental Services <br />