Laserfiche WebLink
:. <br />the dump to be underlain by extensive loose overburden will be • <br />placed over an unmined region in the canyon itself. The general <br />etitent of the mine is shown on Figure 1. <br />3.3 General Geology <br />The following comments are based on data obtained from <br />Colowyo personnel, previous reports and a cursory field mapping <br />of outcrops. The entire bedrock section exposed in Streeter <br />Canyon is in the Williams Fork formation of tiie Mesa Verde <br />group and consists of interbedded sandstone, siltstone, mud- <br />stone, sandy shale, shale, and coal. The beds dip about 3° <br />to 10° to the north and generally range from a few inches to <br />a few feet thick. Permanent joint sets are reported by Wahler <br />Assoc. to strike parallel to and/or normal to t}ie strike of <br />the bedding and dip at greater than 800. The total thick- <br />ness of the Williams Fork formation in the area is probably <br />,. about 800 feet. • <br />{ The overburden in the higher areas of the site and <br />in the canyon walls generally consist of residual soil with <br />colluvium occurring in swales and other topographic lows. <br />'~-+ The thickness of overburden is reported by Wahler Assoc. gen- <br />erally to be about 5-10 feet in the upland areas. Streeter <br />Canyon contains a mixture of colluvium (deposited by slope <br />wash and gravity) and alluvium (water deposited). As dis- <br />cussed below in Section 3.4, the total thickness of over- <br />burden within Streeter Canyon including .fill exceeds 75 feet <br />near its mouth. <br />3.~1 Streeter Canyon Soil Conditi <br />Tl~e canyon floor within ttie area of oux• explorations <br />L is covered by a layer of fill which is underlain by a thick <br />deposit of loose colluvium/alluvium. Below this is residual • <br />~__ <br />~~ <br />L <br />