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adjacent to the bureltole pad. However, topsoil salvage was not done for [his storage area due to the temporary nature of the activity. After topsoil removal, mud pits were dug adjacent to [he drill hole. Drilling Fluids and cutting were discharged into the pits. Drilling muds were used during the course of drilling the surface collar and pilot hole. The surface collar is approximately 5.2 feet in diameter, and the pilot hole was 12.5 inches in diameter. The collar is comprised of two coinpoitents, a surface concrete pad and a liner or casing that extends to bedrock. A concrete centering base is at the bottom of the liner. The ventilation casing was grouted inside of the liner. The concrete pad was poured around the liner, and is approximately 10' X 10' X 2. However, the liner extends tltrouglt the pad, reducing the amount of concrete needed to construct the pad. Approximately 5.5 CY of concrete was required [o cunstruct the pad. The collar and liner are in place and the pilot hole Itas been completed. Raise boring methods were used to coittplete the hole. The hole was reamed to a final diameter of 4.68 feet and a 3' diameter casing was cemented in place from 50' below [he bottom of the Twentymile Sandstone [o the top of the concrete centering pad. The remainder of the casing below the cement hangs in the (tole. The hole is approximately 1100' feet in depth. The 3' diameter casing extends 2' above the concrete surface pad. A 90° elbow, with explosion doors, was placed on top of the 3' diameter casing. Two 15' lengths of ducting ran from [Ile elbow [o the fan locations. The fan was placed on the concrete pad and small utility buildings were constructed to protect the fans. The buildings were approximately 10' X 10' and 12' X 12' respectively, and 8-10' in Iteigltt. These structures have been removed and the three foot diameter shaft has been capped with a metal cover. • Power for the faits was supplied from the substation constructed for the dewatering pumps. A Bite ran over to the fan site, aitd tied into the fan. The line was hung from poles. An auxiliary fan monitoring system was installed to ittonitor motor aitd environment conditions. The line, poles, and monitoring system have been recovered. An access road was constructed linking the fan site to the access road around the dewatering ponds. The road was graveled or covered will[ outer suitable material. A 12" CMP was installed in the diversion ditch oil the east side of the dewatering pond aitd the road constructed over this culvert. Given the limited surface disturbance TCC requested [ha[ [his be considered as a small exemption area, not requiring sediment control. Until vegetation has become reestablished around the pads, a filter fence was placed down slope of the area to trap sediment that may run off from the site. Southwest District Ventilation Borehole In 1994, an exploration (tole was drilled on the prepared drill pad for the Southwest Ventilation Borehole prior to the drilling of the borehole. Access [o the drill site was on the road constructed for the borehole. Mud pits were dug within the bomtdary of the site. The material excavated from the pits were placed adjacent to the pits within the boundary of the site. After drilling ceases the pits, once suitably dry, were backfilled with the material excavated from [hem. A [rash pi[ was dug on the site, or an existing mud pit may be used to collect trash, such as paper, cans, cardboard, etc. Oily rags will not be placed in the pit. The trash pit will be backfilled when it is no loner needed. • The drill (tole was approximately 1100 feet in depth and Itad a nominal diameter of 6 '/. inches. The hole was drilled with water. The water ansmg from the drilling containing cuttmes were passed through the mud pits pnor to being discltar~ed from the site. After the hole was completed, it was longed and then grouted from the bottom PR 97-04 2.05-41 mimioc