OCR Text |
Show Draft Environmental Impact Statements, prepared by bureaus of the Department of the Interior for the larger Tar Sand Triangle proposal and the Circle Cliffs operation, document the extensive water resource impacts associated with such developments. Steam injection techniques use large quantities of water, produce water contaminated with hydrocarbon products requiring disposal as a byproduct of extraction and upgrading, and leave contaminated remainder water in the tar horizon where it could leak into aquifers through fractures. Surface activities disturb the watershed, posing a significant threat of sediment contamination of surface waters that drain into Lake Powell. Brine- containing aquifers pierced or fractured by tar sand operations could potentially leak into fresh- water horizons or onto the surface, a potential impact magnified by the large number of wells required for tar sand operations. Finally, there is the threat of oil spills or spills of byproducts and wastes. The 66,000- acre Orange Cliffs operation would, for example, produce ten tons per day of liquid sulfur wastes to be transported for disposal. Spillage would acidify surface waters coming into contact with the material and kill fish and other aquatic life in the affected drainage. In- situ combustion techniques use less fresh water but result in larger amounts of contaminated water requiring disposal. Water is usually produced in significant quantities with the petroleum. Acidic waters contaminated with hydrocarbons are also left in the formation where they can affect adjoining aquifers or leak to the surface through inadequately sealed wells. Most of the impacts noted for steam techniques could also occur, depending on the exact nature of the operation. Tar sands can be surface- mined in some localities. Should this method be used in the deposits neighboring Glen Canyon, entire surface watersheds could be affected by runoff contamination and discharges from the mines. . The National Park Service will not approve operations having significant adverse effects on NRA resources. Therefore, basic information on the quantity and quality of water resources in potentially affected areas is needed prior to Plan of Operations approval to assess potential impacts. This problem is addressed in an NPS report by Flug ( 1985), which outlines a recommended baseline monitoring program. III. M. 2. Management alternatives. Alternative A: No action Under this alternative existing gauging stations would provide background water data for some of the potentially affected areas. However, the existing stations are upstream of potential operations in some cases, and in others the data gathered is inadequate to document baseline water quality. Under this alternative NPS would not have 58 |