2009-04-20_ENFORCEMENT - M1983176

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the past and what is occurring now. We also have not had time to engage the services of a groundwater hydrologist who has familiarity with these types of situations specific to groundwater mounding behind clay-liners or slurry walls. We are considering that avenue. Our conclusions to backup our assertion that we are not at fault for causing an increase in the rise of alluvial groundwater to the east of the mine site are as follows: 1. Kirk Kirby has been pumping alluvial groundwater from around his property at -250 gallons/minute, 24-hours/day since approximately March 22, 2009 to a ditch that has been historically used for that same purpose and to convey overland water flows from the southeast in years past. That was the specific reason for the construction of that ditch and ditches on the south side of old 120th at the trailer park, since at least the 1950's. Kirk's water has flowed freely down the ditch along Brighton Rd. to the northwest and has not ponded or flooded the road, but has infiltrated back into the alluvial groundwater system and ultimately to the Platte River with relative rapidity. When he has slowed down pumping, the area of infiltration along Brighton Rd. concurrently shrinks within the ditch to the southeast along the road. This location is immediately east of our backfill across Brighton Rd. That area of backfill is shallow and quite permeable. If we were mounding groundwater behind our fill, the water conveyed from Kirk's property would not infiltrate into the alluvial water table, but would have created a very large pond to the east by now or flooded across Brighton Rd. 2. There is already a natural conveyance for groundwater continuing due west from where old 120th Ave. "T's" into Brighton Rd. This is virgin sand and gravel that is located under our neighbors, the Marquez's to the south of us, on a 3-acre parcel and on into an -80 ft. wide swath of land where a set of power poles crosses the Platte River. This is a natural in-place conduit that would act as a French Drain, should the need for increased groundwater flow be required to the Platte River. Our neighbors, the Marquez's, have not experienced abnormally high groundwater conditions at their home. They also have a very low spot in elevation at the rear of their property, that is about the same elevation as Kirk Kirby's property, that shows no signs of elevated groundwater and yet is up- gradient of our fill on two sides. If alluvial groundwater was mounding behind our fill, that area would be a large swamp by now. 3. Based on historic well records, we firmly believe that what has happened is the local groundwater system has "rebounded" or returned to the exact same conditions as before sand and gravel mining occurred in the area. Historic well records show that the static water levels in wells as much as 50 to 80 years ago, are exactly reflective of what they are now. In discussions with the owners of the Henderson Water Ski Club lake to the northeast of us, their lake level has also risen to a higher level than in recent years. In fact, the original irrigation well on Kirk Kirby's property, showed a static water level of only 4 ft. below ground surface in 1939 when it was constructed and again in 1960 when the water right was applied for. We have records from the State Engineers office of at least 9 other wells in the very immediate area that show the same shallow groundwater elevations. 4. Based on several conversations with neighbors in the area, and specifically one neighbor who has lived in the area since 1959, three homes along old 120th Ave. had always experienced leaking basements due to the high groundwater in the area prior to sand and gravel mining activities were active and the local water