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temperature needed for germination of seeds. At Colowyo, soil moisture is not usually a . limiting factor. Soil moisture is usually very high during the spring, due to precipitation during the winter and early spring months. The summer months are generally dry, often with little additional precipitation. By eliminating the use of mulch, the soil temperature is increased earlier in the spring, thus enabling the seeds to germinate earlier when soil moisture conditions are optimum. When the seeds germinate earlier, they are able to utilize soil moisture earlier in the growing season. This results in further root development by the plants, insuring survival through the dry summer months. Only south-facing slopes would benefit from the use of mulch under the moisture conditions at the Colowyo Mine. Without the use of a mulch, erosion control has been maintained with surface manipulation methods such as chiseling on contour, contour furrows, drainage benches and permanent drainage' channels. The initial reclamation at Colowyo that began in 1978 is indisputable evidence that the methods used at Colowyo have proven highly successful in controlling erosion on slopes as steep as 3h:ly until vegetative cover has been established. The Division's concerns were previously directed at vegetative establishment on the unmulched areas. The Division's initial permit concerns were expressed in the following Stipulation No. 4 found on page 32 of the September 28, 1982 MLRD Findings Document. STIPULATION N0.4 If in the future, on-site inspection by the Division or information collected by Colowyo indicate that the suspension of the mulching requirement is detrimental to vegetation • establishment or contributes to excessive erosion, mulching will be resumed." Colowyo has intensively monitored the revegetation every year since 1983 and has reported the data to the Division in its Annual Reports. r~ LJ 2.05-55