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Twin Pines Mine Revegetation Success Findings INTRODUCTION This report has been prepared in support of the termination of jurisdiction for the Twin Pines Mine Site. The site was permitted under the Colorado Surface Coal Mining Act on December 17, 1984 by Twin Pines Investment Ltd. Located in Fremont County in the Canon City Coal Field, the Twin Pines Mine site is in a historically active mining azea. Nearly 200 abandoned mines with the associated surface facilities have disturbed nearly 600 acres in the vicinity of the mine. As a result, the majority of the Twin Pines Mine surface disturbance area is chazacterized by past mining disturbances. The Twin Pines Mine has two distinct azeas: the portal azea and the coal loadout area. The portal bench and access road cover approximately ten acres in an abandoned contour strip mine. The coal loadout is an existing tipple from the Twin Pines No. 1 Mine and covers approximately four acres. Because of the past mining activities there was very little suitable topsoil to salvage. The baseline vegetation survey was prepazed by the U.S. Soil Conservation Service using the undisturbed areas adjacent to the mine which is characterized by a pinyon juniper forest. Ground cover was estimated at 10 to 20 percent. Rock fragments made up 30 to 40 percent of the surface area over the mine site azea. Grasses were estimated to contribute 35-40 percent of the cover, forbs were fairly sparse contributing an estimated 2 percent. The estimated air dry forage production was 500 to 700 pounds per acre. Annual forbs, predominantly Kochia and Russian thistle, dominated the historic strip pit area with scattered rabbitbrush. It was observed by the SCS that reclamation on the abandoned spoil piles completely failed or was never attempted. The mine operator, Twin Pines Investment Ltd., ceased operations in August 1993. Backfilling, grading and topsoiling of the site was completed in the fall of 1995. A mix of native grasses, forbs and shrubs was planted in the fall of 1995. No additional seeding has been conducted since then. A Phase I bond release application was submitted in November 1995. The Division's proposed decision to approved the Backfilling/ grading and drainage control was issued December 18, 1995. The proposed decision became final in January 1996. The Twin Pines Mine permit was revoked and the bond was forfeited by the Mined Land Reclamation Board in May 1996. Cattle grazing on the reclaimed areas has been observed for several years at both the portal area and at the loadout area. Inspector observations indicate that the grazing had a detrimental impact on the revegetation efforts particularly at the loadout. The approved reclamation standazd for the Twin Pines Mine is a minimum ground cover of living plants was to be established which will produce approximately 200 pounds of air dry herbage per year.