2016-02-16_REVISION - M2004031 - Laserfiche WebLink

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Environment, Inc. Page 2 February 12, 2016 been the case and isn' t something new that happens since the relocation of Bull Seep and installation of the slurry wall . The relocation and construction did cause an increase to the groundwater table and did increase the surface flooding to a yearly event since the Bull Seep has allowed to become a weed, chocked drainage . Exacerbating this problem is that Bull Seep is unlined and allows leakage that enters the groundwater table faster since it flows slower then in the past. Review of the 1948 thru 2003 photos show little vegetation was present in the historic channel . I believe that when the channel was relocated, the length increased by approximately 740 feet; the channel slope was decreased by 200, so it slowed the water passage to a point, that it lets cattails and other wetland plants thrive in the channel . This restricts the carrying capacity of the seep so it backs up and floods more often then prior to the move . The new post 2004 photos show that it is out of its bank thru most of the reach from 104`h Ave to the NE corner of the Hazeltine Mine (M- 2004-31) . Some of that may be caused by the Fulton Ditch over flow but this return flow was in place in the 1949 photo and it did not appeared to cause any undue hardship on the Bull Seep prior to the construction and relocation. When you add more water to a drainage that is already flow restricted; increase the groundwater due to a slurry wall and infiltration of seepage, you have a formula for what has happened to the Orr Property. It also appears that since the Bull Seep has become vegetation infested that water backs up in the Fulton overflow drain, flooding the land. The presentation packet for the March 25 , 2015 Enforcement Action contains two plats, 12 & 14, that are graphs of the AI monitoring data and plats 11 & 13 are maps showing the location of the wells graphed. These show, there was an increase in groundwater elevation for the wells east of the slurry wall starting in February 2005 . I have made a minor revision to these plats adding colored coded lines that match the Divisions colors to show the average groundwater elevation (solid line) and the ground elevations for MW' s 1, 2, 3 , 4 , 5, 6A and 11A (dashed lines) . In some cases, i . e. MW' s 1, 3 , 4 , and 5 the increased groundwater elevation does not reach the surface and the 3 wells covered by water are those that are closest to the Orr Property.