2011-05-12_PERMIT FILE - M2011028 (2)

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The two MAPCO pipelines would transport NGL, light hydrocarbons that have been liquefied under pressure. These light hydrocarbons include propane, butane, pentane, or a mixture of these gases. Once released into the environment, these gases are volatilized and quickly evaporate. MAPCO proposes to convert the product carried in their 10-inch-diameter pipeline from NGL to refined petroleum product without additives, and reverse the direction of flow. The time at which this conversion would occur is presently unknown. The potential for release of petroleum product into Ridges Basin Reservoir exists with a leak or break in the MAPCO pipeline. This Biological Assessment addresses potential effects of construction, leaks or breaks in the NGL lines, and leaks or breaks in the petroleum product line following conversion. 4.1.1 Colorado Pikeminnow Pipeline construction activities would not affect Colorado pikeminnow, or destroy or adversely modify critical habitat. Occupied habitat and critical habitat for Colorado pikeminnow are located too far from Ridges Basin to be affected by pipeline construction activities. Occupied habitat and critical habitat are 67 miles and 45 miles, respectively, downstream from the project area. Best management practices would be used by construction crews to minimize spills of hazardous materials that could get into waterways that would lead to habitat in the San Juan River. Operation of the NGL pipelines would not affect the Colorado pikeminnow, or destroy or adversely modify critical habitat. If a leak or break occurs, most of the NGL would volatilize and evaporate, and the remainder would become soluble and dilute in Ridges Basin Reservoir. Materials would not be expected to reach occupied or critical habitat of Colorado pikeminnow. Appropriate avoidance measures would be taken to minimize the risk of a leak or break in these lines, including pipe wall thickness and strength that equals that of the pipeline at stream crossings and in proximity of reservoirs for the Questar, Williams, and Kern River pipeline (Interior 2001). Petroleum product spills from the 10-inch-diameter MAPCO petroleum product pipeline may affect Colorado pikeminnow, if sufficient volume of material were to reach occupied or critical habitat. If a spill occurred into Ridges Basin Reservoir, the petroleum product would be diluted by the volume of water in the reservoir, and further diluted by the volume of water in the Animas River, if the spill escaped from the reservoir. A petroleum product spill in Ridges Basin Reservoir could be contained by not allowing water releases from the reservoir. This would negate any possibility for petroleum product reaching occupied or critical habitat of Colorado pikeminnow. If petroleum product reached the Animas River and eventually occupied or critical habitat of Colorado pikeminnow in the San Juan River, the most toxic fractions would be evaporated, including benzene, hexane, octane, and decane. The amount of residue reaching these downstream areas would be small and greatly diluted. The fraction of polycyclic aromatic hydrocarbons (PAHs), also known as polynuclear aromatic hydrocarbons (PNAs), is small in refined petroleum product, and the volume reaching occupied or critical habitat of Colorado pikeminnow is expected to be insignificant. 4.1.2 Razorback Sucker Pipeline construction activities would not affect razorback sucker, or destroy or adversely modify critical habitat. Occupied habitat and critical habitat for razorback sucker are located too far from Ridges Basin to be affected by pipeline construction activities. Occupied habitat and critical habitat are 67 miles downstream from the project area. Best management practices would be used by construction crews to minimize spills of hazardous materials that could get into waterways that would lead to habitat in the San Juan River. B-11 Weerninuche Construction Authority P.O. Box AA - Towaoc, CO 81334 ,L?,r-i ? rvl A S Ea l./.a c. (E (C. ?e ?i?V?. L EV--SI51T tf ' PA?6 H-b15 t