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<br />water drainage, the pipes would be placed at least 5 feet below the bottom of the <br />streambed. The pipes will be constructed of steel and will have three layers of <br />insulation. Thus, a breach is unlikely to occur except under an extreme seismic event, <br />and the project area is in an area of low seismicity. <br />The pipeline will cross Piceance Creek in two locations, Stewart Gulch in two locations, <br />and Parachute Creek in two locations. There will also be a small wetland crossing in <br />Middle Fork Stewart Gulch. There will be no "river" crossings for the pipeline. More <br />information on the pipeline is provided in the Pipeline Information Summary <br />(American Soda 1998), which is enclosed with this 112 Permit Application. <br />At the Piceance Site and the Parachute Site, site protection plans will be developed as <br />appropriate. These plans may include Stormwater Permits, Stormwater Management <br />Plans, erosion control plans (see Exhibit E), and other spill response plans. The plans <br />would include requirements for structural and nonstructural controls to protect surface <br />water. Structural controls, if necessary, would include berms, impermeable ground <br />surfaces, surface drainage systems, sediment barriers, mulch applications, and other <br />structures. Nonstructural controls would include BMPs, employee training, surface <br />runoff testing, and other measures. <br />G.2.2 Groundwater Quality Effects <br />This discussion of groundwater effects is limited to the Piceance Site because mining <br />does not occur at the Parachute Site or along the pipeline corridor. Solution mining at <br />the Piceance Site involves pumping mining solutions into and out of solution mining <br />cavities located in the Saline Zone. Communication of these sodium bicarbonate- <br />bearing mining solutions with overlying strata could result in potential water quality <br />impacts to the Uinta Formation portion of the Upper Aquifer (see Section G.1.2), which <br />is considered to be a potential USDW. However, site conditions and a number of <br />specific measures proposed by American Soda, will minimize the potential for impacts <br />to the Uinta Formation portion of the Upper Aquifer. <br />First and foremost, it is imperative to recognize that maintaining a pressurized, <br />confined system is essential to American Soda's mining process. If leakage from the <br />cavities were to occur, there would be a corresponding loss of pressure, and the well <br />would have to be shut in and corrective action taken. Pressure at each well will be <br />continually monitored, so that, if a leak were to occur, it would be detectable almost <br />immediately, and corrective action would be taken. Therefore, the potential for large <br />volumes of fluid to be introduced into the aquifer system is minimized. <br />Secondly, the wellbore casing will be set to about 150 feet below the lowermost extent of <br />the aquifer layers (the Dissolution Surface). The casing will be cemented to surface with <br />a heat-resistant cement to isolate the aquifers. Mining fluids will be further contained <br />within a tubing system. American Soda has provided a buffer zone of about 150 feet of <br />G-9 <br />