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DAM REHABILITATION <br />A. Pak Reservoir <br />Once the District decided to move fonward, the next issue was to advertise the project and request bids. <br />The project was bid out in July of 2010; the bids were read an September 10, 2010 at the open bid meeting <br />and then presented to the District The District investigated a number of contractors for qualifications and <br />selected Peterson Excavating. He was the low bidder as well as very well qualified with an excellent <br />reputation. <br />Peterson Excavating (contractor) began construction in late June of 2011 . The intent of the contractor was <br />to start by removing the existing trees that were in the Impoundment area, removing and stockpiling the <br />existing embankment material onsite to be used in the new dam, and remove all the excess material to a <br />prearranged storage facility on the USFS Mineral Parr gravel pit. The con tractor felt that he would get the <br />material out of the " mined" area and leave enough at the end to do the embankment. The District and the <br />engineer were in concurrence with the construction sequence presented by the contractor. The conmaor <br />was able to get the trees cut and the existing dam moved but ran into a problem with the material to be <br />" mined ". The original soils survey indicated that there was only 2 feet of overburden on the good stn wMral <br />material that we needed for construction of the dam and it was located close to the proposed dam. <br />However, once on site the contractor discovered that the overburden proved to be closer to 4 to 6 feet and <br />the area of best soils was further from the dam. Also as a requirement of the approval from Dam Safety, <br />the soils engineer was to be contacted and the soils retested. While the soils were being retested and a nee <br />report generated the contractor continued with the transferring of material from the "mined" area Because <br />of the increase of unusable overburden, the amount of material to be mined increased. M mwb le the total <br />maximum amount of allowed fill stockpiled on the Mmeral Park area was reached It still left more to be <br />removed for the use on the new dam cinbankinent. The contractor, District, and engineer agreed that we <br />needed to "dig a hole" to get at our useable material and fill the "hole" back in with the unusable <br />overburden. All of this increased the cost for the construction of the Peak Reservoir and caused an overrun. <br />funds. In October of 2011, the contractor was forced to shut down for the winter. <br />In July 2012, the contractor was able to return to the site. He began the over - excavation for the <br />embankment and he immediaidy encountered three separate underground springs which were directed to <br />the over -excavations. Because the springs world undermine the structural integrity of the new dam they <br />needed to be intercepted and redirected The contractor, District representative and civil engineer met on <br />site and discussed various alternatives to resolve the spring issue. One spring affected the south end of the <br />dam and the other two were located at the north end The south spring was intercepted with a plastic drain <br />and redirected into the main reservoir ping area The other two springs proved to be more difficult and <br />required a clay cutoff wall, a few hundred tons of rock as a stabilizer for the dam base and additional over - <br />excavation. Of course all of these tmwMectad occurrences cued additional costs to the project. Once <br />these problems were resolved, the contractor was able to construct the new embankment. In October of <br />2012, because of weather, the contractor was forced to close down for the winter. However, before he left <br />for the winter, he had constructed the new embankment, and outlet pipe. The 2013 constinrction season will <br />bring the project to completion with the installation of the outlet gate works, emergency overflow <br />construction, rip rap on the face of the dam, reseeding and wetland mitigation. <br />The Dam Safety Representative has made the Wspmhons as required during the construction of the <br />embankment and will also inspect the overflow and outlet structure once they are installed. All of the <br />inspections are a precursor to the final approval based on an as-buih to be submitted to the Division of <br />Water Resources and water storage can begin. It is anticipated that the reservoir will be available for <br />storage during the winter of 2013 — 2014. <br />B. Blanche Paris <br />Blanche Park is the second of the projects undertaken by the District for rehabilitation. As described <br />previously, all information from the District and the consultads has been subitted to the respective agencies <br />for approval and has been through previous reviews. Since Blanche Park will be utilizing the export <br />material from Peak Reservoir, no excavation of the upstream pondintg area will be needed. The existing <br />15 <br />