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Applegate Group, Inc. Water Resource Advisors for the West September 18, 2015 Mr. Tyler O'Donnell Division of Reclamation, Mining and Safety 1313 Sherman Street, RM 215 Denver, CO 80203 SEP 18 2015 DIVISION OF RECLAMATION MINING ANQ ;A; ; I v RE: Brannan Sand & Gravel Company Pit 29, Permit No. M-1980-183, Amendment to AM -02: Frei Objection Dear Mr. O'Donnell: We are in receipt of the letter from Albert Frei & Sons dated August 10, 2015. The following are responses to the objections raised in that letter. Frei questions the elevation of the french drain on the south side of the north cell of Pit 29 and suggests that it should be deeper. Due to the physical constraints of the proximity of the trench to the Pit 29 slurry wall and the utilities in the Brighton Road right -of- way, we have concerns that a deeper trench will be more difficult to construct and will stand a greater chance of impacting the slurry wall and utilities. Frei states that they have NAD88 monuments that they would presumably prefer we use. Unfortunately the historic map was created in 1980 and the NAD 88 datum was not yet established. Purportedly there has been an unknown data shift since the datum used in 1980. In our amendment application we show elevations of the drain on Exhibit E. The elevations in the amendment are based on lowering the water level to 5007 at the west end. This is 4 feet lower than the standing water observed in the Einspahr pasture in 2014. It may be entirely possible that the present 5007 elevation is the same as the 5005 elevation in the pre-NAD88 survey. In any event, we believe that lowering the water level by four feet is sufficient to minimize the disruption to the hydrologic balance. The Division reached a similar conclusion in its adequacy review dated July 27, 2015 wherein it stated that this design "will closely mimic the pre -mining groundwater gradient and elevations." Furthermore, Norm Einspahr has expressed concern that a deeper drain could have adverse impacts on his shallow well. As you may know cottonwood trees on the Einspahr property were killed by lowering the water table as a result of Frei's pumping the Worthing Pit. Frei also asked for a design for a splash basin. Frei makes reference to an Exhibit D and construction plans. I am unaware of an Exhibit D or reference to construction plans. Perhaps he intended to say Exhibit E., I have revised Exhibit E to reflect the addition of a protective apron at the outlet to the ditch on the Frei property. I included a typical plan and profile on page 2. 7405 W. Highway 50, Suite 123 1490 W. 1215' Avenue, Suite 100 118 W. 6`h Street, Suite 100 Salida, CO 81201 Denver, CO 80234 Glenwood Springs, CO 81601 303-452-6611 www.applegategroup.com