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• (Page 2) • MINE ID # OR PROSPECTING ID # M-80-131 INSPECTION DATE 8/28/97 INSPECTOR'S INITIALS ACS On August 28, 1997, the Division of Minerals and Geology conducted an inspection of the Bunn Ranch Pit located southeast of Craig, Colorado. On December 9, 1997, the Division reviewed the current flood plain maps for the area of the pit that are on file at the Colorado Water Conservation Board offices in Denver. These actions were taken in response to a complaint filed with the Division by an adjacent landowner, Mr. Robert Deakins, that activities at the pit have caused flooding on his pasture located just to the north of the gravel operation. The following observations were made during the site inspection: 1. The relationship of the Bunn Ranch Pit to the channel of the Yampa River is as follows. The main channel of the Yampa River is adjacent and to the south of the permit area for the gravel operation. The Ana Branch of the Yampa River is a side channel to the river. The inlet from the Yampa River to the Ana Branch is a short distance upstream (east) of the Bunn Ranch Pit. The outlet of the Ana Branch to the Yampa River is located a short distance downstream (west) of the pit. The Ana Branch meanders around and through the Bunn Ranch Pit permit area, with most of the mining occurring south of the Ana Branch (between the Ana Branch and the main channel of the Yampa River), but with the office and gravel stockpile area located to the north of the Ana Branch. 2. The relationship of the Bunn Ranch Pit to the Deakins' property is as follows. The access road to the Bunn Ranch Pit runs from north to south from Highway 40, through the Deakins' property, to the pit office area. The Deakins' property includes pastures to the east and west of this access road. The Deakins' pasture east of the access road is bounded on the east side by the Ana Branch (which is running from north to south along this particular reach), on the north edge by the railroad embankment, on the south edge by the Bunn Ranch Pit stockpile area, and on the west edge by the pit access road embankment. 3. The Yampa River system was subject to widespread flooding during the spring and early summer of 1997. The operator of the Bunn Ranch pit constructed and maintained a berm at the north boundary of the stockpile/office area to keep overbank flows from the Ana Branch from flooding the stockpile/office area. With this berm located at the south edge of the Deakins' east pasture, and the road embankment located at the west edge of the Deakins' east pasture, drainage of the pasture in these directions was prevented. As such, the depth of flooding in the pasture may have been increased slightly. The operator is willing to install three 18-inch culverts through the access road to allow the Deakins' east pasture to drain to the west. Mr. Deakins may contact the Division of Minerals and Geology or the operator if installation of the culverts is desired. 4. The pit located at the extreme southwest corner of the Bunn Ranch permit area was inspected. It was observed that during 1997 flooding, Ana Branch flows had overtopped the dike between the pit and the channel, and had spilled into the pit lake. Storage of flood flows in this pit lake would have slightly lowered flood depths in the nearby areas. Additional flood storage would also have been created by excavation of the other pits at the property, even though the pits are surrounded by flood protection berms. The flood storage is provided by subsurface flow into the pits. 5. The inlet to the Ana Branch from the Yampa River was inspected. This inlet was armored with rip rap at some time in the past, but this riprap has deteriorated, and is no longer preventing erosion at the inlet. This inlet is not within the Bunn Ranch permit area. 6. A head-cutting prevention structure across the Ana Branch located downstream from the