2015-02-24_REVISION - M1997065 (3)

Home Browse Search

EXHIBIT D — MINING PLAN BROWNSTONE QUARRY AMENDMENT — 2015 The mining plan is executed in sequential stages to minimize the amount of disturbed land at any one given time. This 4.4 acre area has a high quality Brownstone formation, often referred to as the Plainview Formation in geologic maps, which is 15 feet thick (confidential). The stratum of material immediately below the Brownstone is shale. The low volume nature of this operation, maximum of 4 to 5 thousand tons sold per year, lends itself to small areas, of about 75' x 75', being excavated sequentially from north to south. Topsoil will be stripped where present, stockpiled and planted with native seed to prevent runoff. A strata, 1' to 10', of overburden is then moved to the vacant adjacent area which exposes the Brownstone formation in about 75' x 75' stages. Excess overburden is stockpiled in an area approximately 500 feet to the north on the existing permitted area. No blasting is necessary as the formation has existing horizontal and vertical seams. An excavator is used to extract and separate the Brownstone, which is the primary commodity, into saw blocks, boulders, veneer and rubble. No secondary commodities are sold in the operation. Front end loaders with forks are then used to move the separated material to the appropriate place in the quarry layout. As the Brownstone in a given area is excavated the overburden and rubble are placed back in the adjacent vacant excavation to minimize double handling and as a first step in the reclamation process. The excavation is moving from north to south in the existing permitted area and will continue in the same manner in the proposed 4.4 acre amendment. Considering the current market demand for Brownstone products and supply available in this proposed area, the overall expectation is an increased 10 years of operation (confidential) given a consistent market demand going forward. Due to the variability in Brownstone, for example; size of blocks, color and texture, several different areas in the existing permitted area are worked in co- ordination with the demand of a given order or market trend. The excavated area provides for a stormwater retention /detention system when a significant rain or snow occurs. The collected stormwater is held until it can slowly leach through the ground below or evaporate, which can take up to 10, days after a severe storm event. Stone Wholesale, Inc. currently operates under Colorado Department of Public Health and Environment Stormwater permit number COR34 -1454. As a backup feature to this plan to prevent stormwater runoff, a 4' to 5' high, 350' long earthen berm will be placed along the southwest border of the proposed area as this is the lowest elevation in the whole quarry. The berm will be seeded with native seed to prevent runoff and add to the view shed to the southwest. This stormwater plan has worked since 1997 with no problems, even through the 500 year flood of September 2013, in the existing quarry DRMS M- 1997 -065 and will continue to work for the proposed amendment.