The Five Mines - Midwest Mine
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The Midwest Mine was a late addition to the Creede Mining District; in 1923 the Midwest Mining Company began working on extracting minerals from the claim. Within two years miners had cleared out the Midwest Tunnel and blasted underneath the ore body suspected by above ground investigation. The ore they did find proved to be unprofitable and by 1925 the Midwest Mining Company had stopped operations. In 1968 the New Midwest Mining Company had acquired the mine and installed a surface plant, a shop with power appliances and an upgraded rail line complete with a diesel locomotive. The mine was sold to other investors who sought profit from the mine, but was abandoned in 1984.
When abandoned the historic remnants of the Midwest Mine had been erased. Buildings, rail lines and waste piles remain from the large investment the New Midwest Mining Company. The Willow Creek Reclamation Committee focused on reducing the heavy metal loading to Nelson Creek from the Midwest Mine by moving and consolidating leftover mine waste. A large trench was excavated near the collapsed portal and filled with the waste rock. The waste rock was then capped with the excavated material, amended with limestone and mushroom compost and seed was incorporated into this new soil. In addition to these strategies, French drain pipes were installed to capture water coming in off the roadway. The pipes were laid to discharge water below the waste piles and away from the creek.
Finally, the area where waste rock had been was covered with limestone, top soil and mushroom compost to promote growth of the seed mix that followed. The final step on this project was to lay weed free mulch and then crimped into the soil to ensure good seed/soil contact and to retain water moisture.
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Reclamation at the Midwest Mine will include consolidation and capping of the scattered mine waste, and miscellaneous hydrologic controls. The road adjacent to the mine leading to East Willow Creek also contains some mine waste. This area will be covered with fines from the excavated disposal area after lime application. There are several buildings and a trestle at the mine that must not be damaged by construction.
Approximately 2,100 cubic yards of mine waste will be deposited in a trench/cut located near the collapsed portal of the mine. The trench must be excavated, and the excavated material must be stockpiled in a location designated by the PROJECT MANAGER. The trench shall extend from the ventilation building to approximately 50 feet east of the portal structure. The ventilation building will be demolished or moved to facilitate construction of the disposal area. Care must be taken during construction to not damage the exposed portion of the portal structure and the core shack. A mine closure monument is located north of the ventilation building at a backfilled portal. This monument must be removed and replaced following placement of the mine waste and soil cap.
The PROJECT MANAGER will stake the boundaries of the disposal area. It is estimated that approximately 1,400 cubic yards of material will be removed in the disposal area. The disposal area will be excavated to the existing level of the bench between the buildings. A small portion of the excavated material will be place in a pond on the east side of the Nelson/East Willow Creek road across from the lower bench of waste rock. The entire area between the ventilation building and the portal structure can be excavated. However, the portion from the portal structure, east, must be excavated as a trench. The cut slope shall not have a slope steeper than 1h:2v. A portion of the partially collapsed, timbered entry will be excavated. This will expose the underground workings. The underground workings must be backfilled with mine waste for a minimum of 15 feet from the north boundary of the excavation.
Following excavation of the disposal area, approximately 2,100 cubic yards of mine waste will be consolidated in the excavated area. Approximately 900 cubic yards will be moved from the lower bench and1,200 cubic yards from the middle bench. The mine waste at the trestle area will not be moved. Approximately 100 cubic yards of mine waste located adjacent to Nelson Creek will be consolidated with the mine waste under the trestle to reduce the slopes. It is acceptable to construct the disposal area in stages to reduce double handling of the cover material. The mine waste must be capped with a minimum of two feet of excavated soil. The fill height/final grade must conform to the adjacent existing undisturbed slopes. Any excess material excavated from the disposal area must be spread evenly throughout the mine waste removal area.
Approximately 1 acre of disturbed area will be revegetated per:
Limestone will be added to the mine waste disposal area and the undisturbed mine waste to reduce metals leaching from the site. Approximately 40 tons of minus 40 mesh limestone with a minimum of 90% CaCO3 equivalent will be uniformly spread over the removal area and the exposed mine waste prior to topsoil placement. Limestone must be spread inside the track/trestle by hand methods.
Approximately 400 feet of roadway was constructed with mine waste from the Midwest Mine. Hydrated lime or cement kiln dust must be placed on the road surface, and then the lime/kiln dust must be covered with fine material excavated from the disposal area. Five tons of cement kiln dust or 2.5 tons of hydrated lime is required. The lime/kiln dust must be covered with six inches of soil material. The lime/kiln dust must be wetted prior to application of the soil material.