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r (Page 2) MINE ID ; OR PROSPECTING ID ~` M-77-393 INSPECTION DATE 6-2-96 INSPECTOR'S INITIALS ACS OBSERVATIONS This inspection was conducted with representatives of the City of Boulder O~~en Space (City). The City ie reclaiming the Jenkins Pit under the terms of an agreement with Varra Companies. Overall, the revegetation effort completed in the spring of 1995 has resulted in a very good growth of grasses at the site that is south of Coal Creek. Grave ie establishing in the former processing area near the center of the south site. If grass become~e established in this area sufficient to meet the performance standard for bond release, the coarse sands and gravels left over from processing would not necessarily have to be scraped-up. The areas where initial grass establishment has not occurred are the pit highwall at. the west end of the Bite, a clayey area west and south of the Coal Creek crossing, and a large area at the east end of the south site. The west highwall elope needs to be graded no citeeper than 3:1, and needs to be revegetated. The west highwall elope ie probably a good area to use some of the remaining stockpiled topsoil. In the clayey area south and west of they creek crossing, the City intends to reseed with a heavy application of straight Western Whetttgraee, which ie amenable to clayey soils. This plan is acceptable to the Division, however, if grave does not become established in this area, the clayey soils will have to be covered with a minimum of 10 inches of non-clay overburden and topsoil as specified in the reclamation plan. The area at the east end of the south site is infested with Diffuse Knapweed. The City ie currently prohibited from using aerial herbicide application in this location because of proximity to the creek, and land application using a tractor would be difficult because of rough terrain. The City intends to use a eheepefoot compactor to try to smooth out the ruts left by ripping that was done in 1995. If the ground can be sufficiently smoothed, tractor application of herbicide will be used. Concurrent with weed control effortci, the City needs to reseed this area; use of some of the remaining stockpiled topsoil ie recommended. Some of the ideas that the City has for ongoing site reclamation were discussed. The City would like to establish a mesic tall grass community to enhance wildlife habitat on the lower terrace along the creek. Eleven piezometers were installed to evaluate t:he potential for subirrigation in this regard. The City would also like to leave some wei: areas with the potential for seasonal ponding throughout the reclaimed landscape. Also, the City would like to establish shrubs, ouch as Mountain Mahogany, on the graded piles of graved that remain at the south site. These plane would be consistent with a poet-mining land use of rangeland, ae long as the wet areas are limited in extent and number, i.e., are conaietf~nt with the type of ponds that might be established for livestock watering. Obviously, the ponds could only be filled using the City•e decreed water rights in priority. At the borrow pit north of Coal Creek, the City has graded that area west: of the pit for positive drainage. This area has been seeded, and shrubs have been planted. The City intends to push the road fill located north of the pit down into the pit. The City will establish 3:1 elopes in the borrow pit. If material stockpiles located at: the north Bite cannot be marketed, they will be pushed into the pit. In general, reclamation of the Jenkins Pit ie progressing well. The most problematic aspect of site reclamation will be control of Diffuse Knapweed. The $96,625.00 Mond held by the Division ie sufficient to assure site reclamation to a rangeland end-use. cc: Carl Mount• DMG Glen Carrifar City of Boulder Open Space P.O. Box 751 I ~ E Contact Address NAME Chris Varra OPERATOR Varra Companies. Inc. STREET 2130 S. 96th Street CITY/STATE/ZIP Broomfield. CO 80020 Boulder, CU 80306 ~ CE ~ BL ~ FS ^ HW ~ HMWMD (CH) ~ SE ~ WQCD (CH) ~ OTHER