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<br />EXI-IIBIT G <br />WATER INFORMATION <br />The proposed special use area lies in the St. Vrain River Valley south of the St. <br />Vrain. The valley bottom land surface has a gentle slope of approximately 1:150 to <br />the southeast. The site is chazacterized by flood plain features such as isolated <br />wetlands meander scars and stream terraces which aze typical of the streams east of <br />the Front Range. The subject property contains a number of significant surface water <br />features including the following: <br />• Approximately 12,600 feet of the St. Vrain River passes through or <br />adjacent to the Lyons site. That portion of the river that passes through <br />the site is to be found on the Rockin' WP-North or Miller properties, both <br />of which have been previously permitted by DMG. <br />• The south branch of the St. Vrain originates immediately north of [he East <br />Plant phase of [his project and flows southeasterly across the Rockin' WP <br />and Miller properties. Approximately 9,600 feet of the south branch cross <br />the Lyons site. <br />• As a result of previous mining and reclamation activities there aze three <br />ground water-fed lakes and one reservoir contained on the Rockin' WP- <br />North pazcel. The reservoir was constructed following mining in order to <br />provide augmentation water to the St. Vrain system. <br />• Numerous irrigation ditches and laterals cross the subject property <br />including the Foothills Reservoir outlet channel, which crosses a portion of <br />Rockin' WP-South and the Miller properties. The Foothills Reservoir <br />inlet channel is to be found parallel to the Southwest Portland's main <br />access road, between the West Plant and East Plant phases. <br />• The site also contains several small ponds that were more than likely <br />created to water livestock. <br />The majority of the site lies within the boundazies of the 100-year flood plain as <br />mapped by Love and Associates in their study dated December 16, 1992. Flood <br />flows East of the cement plant split into two flood plains separated by shallow sheet <br />flows across the East Plant and Rockin' WP parcels. Once mining and reclamation <br />activities have been completed significant flood storage will have been added to this <br />azea of the St. Vrain flood plain. <br />The sand and gravel mining operation will not require any treated water. Non- <br />treated water in the form of ground and surface water will be used primarily for the <br />Western Mobile Lyons -Rockin' WP G-1 <br />