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quality and supplies. Much of the conflict is rooted in widely discussed changes in the population of the West as recreational and preservationist interests increasingly clash with traditional extractive industries. 4 CBM and produced water CBM is trapped within coal seams. Methane attaches to the surface areas of coal and is held in place by water pressure. Methane remains in a coalbed as long as the water table is higher than the coal. When the water is released, the gas flows through the fractures into a well bore or migrates to the surface. Drilling initially produces primarily water; gas production eventually increases and water production declines. When the CBM is extracted, the water must be separated, the gas is sent to pipes, and the water is dumped into ponds or injected back into the ground. In order to develop the resource, companies must first pump large quantities of water from the ground, about 12,000 gallons a day on average for each well, to release the methane. The development transforms the landscape with pipes, roads, compressor stations and power lines, and discharged water that is often not useable for irrigation and, in some places, is rein- jected into underground regions (Figure 2). Here's the average water production from CBM wells, in gallons per well per day: Powder River 16,800 Raton 11,172 San Juan 1,050 Uinta 9,030 San Juan Basin 1,200 wells have produced 36 billion gallons of water Wyoming portion of the in the next 15 years, ap- Powder River Basin proximately 51,000 wells will have produced over 1.4 trillion gallons of water Managing produced water The development of CBM has sometimes pitted energy developers against other users of the affected water. Issues surrounding CBM development and water include: (1) underground water quantity and the possibility that drilling for CBM contaminates aquifers with water of lower quality; (2) water rights and underground water supplies that may be diminished as dewatering occurs; (3) groundwater that may be contaminated by discharged water that is polluted; and Figure 2. Coalbed Methane Development Avoids Contamination of Water Supplies (4) aquatic areas, stream beds, and local ecosystems that are unaccustomed to receiving such large volumes of water. Options for dealing with the large quanti- ties of water released include the following (costs generally in- crease as one moves down the list): 5 -Traditional surface discharge: water is allowed to travel downstream and be absorbed or evapo- rate as it moves. •Irrigation: water re- leased to agricultural areas. -Treatment: water is treated to improve quality. -Containment with reservoirs: water is piped to a surface impoundment where it is absorbed or