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comprises 166 acres (4 percent) of the Piceance Site, of which only about 9 acres would be disturbed for mining operations, and an additional 5 acres would experience temporary construction disturbance. Greasewood Association -The Greasewood Association is limited primarily to low elevation drainage bottoms that have deep, saline-alkaline, poorly drained alluvial soils. At the Piceance Site, this association occurs primarily on Hagga and Havre loams on the Piceance Creek floodplain. This association is intermixed with saltbush and sagebrush on lower saline-alkaline soils (BLM 1994). Either big sagebrush or greasewood may dominate, depending on the soil type (Tiedeman and Terwilliger 1978). The Greasewood Association is usually an open to closed (greater than 80 percent cover) stand of greasewood and sagebrush. At the Piceance Site, the overstory ranges from sparse (20 to 50 percent cover) to open (50 to 80 percent cover). Understory growth in dense stands is usually very sparse, but open stands support a mixture of perennial shrubs and have a perennial and annual grass-forb under~tory (BLM 1994). Understory grasses include western wheatgrass and cheat grass. The most common fortis are lambsquarters, three- nerve fleabane, and mustard (Tiedeman and Terwilliger 1978). The more open areas provide limited wildlife habitat. The Greasewood Association comprises 153 acres (4 percent) at the Piceance Site, of which only negligible amounts would be affected by the project. Remnant Vegetation Association -The Piceance Site contains one of the only stands of ponderosa pine currently known to occur in the Piceance Creek Basin. This remnant vegetation association (RVA) is probably a relict from an earlier period when conditions in this region were more favorable for ponderosa pine. The site occurs near the head of a small draw on a gentle south-facing slope in an area otherwise dominated by pinyon-juniper woodlands. The location of this RVA is shown on Figure J-1. The RVA contains approximately 11 trees and is about 30 acres in size, including a small buffer zone sufficient for protection of potential reproduction. The RVA occupies the Torriorthents-Rock outcrop complex and Rentsac channery sandy loam soils. J.2 Pipeline Corridor The project pipeline route may be described according to three geographical- jurisdictional segments. The first segment extends from the initial processing plant at the Piceance Site and generally southeast to the Greasewood Compressor Station, which is located on an existing north-south natural gas pipeline corridor. This first segment is approximately 9 miles long, including 2 miles that are within the Piceance Site, and primarily occupies BLM land. The last 2 miles of this segment parallel an existing east- westnatural gas pipeline corridor. J-5