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sss AFFIDAVIT OF JON R. FORD, P.E. STATE OF COLORADO ) ss. CITY AND COUNTY OF DENVER ) Jon R. Ford, P.E. being first duly sworn upon oath, does depose and state as follows: 1. I am the employed as a Vice President of Leonard Rice Consulting Water Engineers, Inc. ("LRCWE") located at 2401 Fifteenth Street, Suite 300, Denver, Colorado where I have worked as a Senior Ground Water Geologist since May,1989. 2. LRCWE was involved in assessing the impacts on the ground water system prior to the approval of the original mining permit issued to Flatirons Sand and Gravel Company in the late 1970's and again when the permit area was enlarged in 1988. 3. The Deepe Farm Pit site (the "site") is located on a broad terrace (about 3,000 feet wide) west of South Boulder Creek. Just west of the site and east of South Boulder Creek is another terrace about 50 feet higher. See Figure 1. The lower terrace is underlain by sand and gravel deposited during the last ice age by the ancestor to South Boulder Creek. 4. Ground water flows through the sand and grave] aquifer to the north down the valley (the lower terrace) parallel to South Boulder Creek. The aquifer is bounded by the higher terrace to the east and west because the terrace is composed of impermeable shale. The bottom of the aquifer is at the boundary between the sand and gravel and the underlying impermeable shale. See Figure 1. 5. The site was dewatered so that mining could occur. This was accomplished by installation of an interceptor trench that cut through the sand and gravel to shale. Mining removed essentially all of the aquifer within the mined areas. See Figure 1. Today a thin veneer of sand and gravel generally less than a foot thick remains. In some places this material is only water saturated during wet periods of the year. In other places,ground water from outside the mined area flows into the mined area and through the thin remnant of sand and gravel. 6. The fine fraction left after sand and gravel was removed from the mined material was used to backfill portions of the mined area. The Stage 4 area at the extreme southern extent of the permit area was refilled with fines to within a few feet of pre-mining elevations. The area located southeast of the Stage 1 area outside the berm at the site was also backfilled with fines. 7. Decreasing the number and size of the pit lakes will not negatively impact the ground water system in the area of the Deepe Farm Pit. Since the aquifer has essentially been removed within the mined area, the lakes would have to be constructed by excavating the shale layer. See Figure 1. Water to fill the lakes would then come from intercepting what little ground water flowed WMI EXHIBIT NO.24