_INSPECTION - C1981015 (18) - Laserfiche WebLink

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d. III. COMMENTS - COMPLIANCE Below are comments on the inspection. The comments include discussion of observations made during the inspection. Comments also describe any enforcement actions taken during the inspection and the facts or evidence supporting the enforcement action. This was a complete quarterly inspection of the reclaimed Fruita mine permit revocation site, conducted by Dan Mathews of the DBMS Grand Junction Field Office. Weather was clear and very warm. A remedial reclamation project was performed at the site earlier this spring. The Division's Inactive Mine Program (IMP) developed the maintenance plan and bid documents for the project, utilizing a combination of remaining forfeited bond funds and a grant from the OSM civil penalties fund. The construction contractor performed the work in March-early April. See June 2009 inspection report for details of the work completed. A follow-up project is scheduled for this fall, to include roughening and seeding the smoothly graded #2 portal backfill where seeded vegetation did not establish well, along with remedial seeding of other areas if warranted, and erosion repairs as necessary. Signs and Markers The old gate with the DMG revoked permit I.D. sign has been removed from the site. Hydrologic Balance and Backfill & Grading It was evident that a major storm event occurred at the site and in the watershed upgradient from the disturbed areas at some point subsequent to the June 4, 2009 inspection. The sediment pond had been completely filled with sediment to the spillway elevation, and there was evidence of significant flow in all drainage channels on the site. The portal on the #1 Mine Bench, which had been opened and repaired with polyurethane foam, backfill, and a surficial rock apron in the spring of 2009, held up well, as did the channel with large rock check installations immediately down drainage from the repaired portal. However, there was evidence of concentrated flow and erosional scour across the portal backfill immediately to the west of the rock apron. In a number of locations across the site, previously installed rock check structures were damaged to varying degrees. There was significant rill erosion along the lower portion of the portal bench access road, channel incision along certain channel reaches downstream of the toe of the #1 Mine outslope and the tributary channel further west. There was also evidence that rock had been dislodged from several locations along the steep riprapped #1 outslope channel, and a large accumulation of rock had been deposited near the base of that channel at the toe of the outslope. The IMP program is preparing a scope of work document, and the project will be bid out, and remedial erosion repairs and reseeding will be completed in the fall of 2009. Revegetation Areas disturbed in association with the recent stabilization project were roughened and seeded with the following seed mix: Species Variety PLS Pounds per Acre 3