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II . II . . Western States Water Council Water Quality Committee Sheridan, Wyoming October 5,2006 John utilized a powerpoint presentation. When people talk about the Powder River Basin, keep in mind that it is more a term of art rather than a term of geography. There are several drainages involved. Sheridan is in the Tongue River drainage. The Tongue River is a high quality mountain stream flowing out of the Big Horn Mountains. It is a very good quality stream. It is, in fact, a blue ribbon trout stream at its headwaters. It is a much different stream than the Powder River. The Powder River mostly drains plains country. It is very arid and it's quite flashy, so it can be very muddy. The quality of the Powder River is quite different than that of the Tongue River. About one thousand individual discharge permits for coal bed methane (CBM) have been permitted in Wyoming. Each permit has about 10, outfalls. Companies tend to over permit. They will permit a site for ten outfalls, and they may only build three outfalls. If they get more water than they expected, they may build a couple more. If they get less water, then three outfalls may be sufficient Thus, it is a slightly misleading picture. Each permit is looked at rather closely. The vast majority of the discharges permitted are discharges to either onstream reservoirs, the equivalent of stock ponds, or off channel reservoirs. The permits are based on the downstream uses. The NPDES program has grown significantly since the late 1990s. There are six people on staff just to permit CBM. Another 6-8 staff go out and monitor. There are approximately 1800 total permits in Wyoming, and about 1000 are for CBM. Of the 1800, about 500 are conventional water and gas permits. All of these are subject to stormwater control. Of the entire area of discharges, there is about 100 cfs of water. It is spread out, and much is not going directly down drainages. Much of the water goes into the various reservoirs. Water is disposed of by putting it in in-channel reservoirs. Secondly, is off-channel reservoirs, and then direct discharge. Only about 2% of the total is injected. A very small percentage is subsurface irrigation. Off-chamlel ponds must be out of the natural drainage and cannot get anything into them except that which falls directly from the sky. They may be lined or unlined depending on the groundwater situation. On-channel are basically like stock ponds. It is all very site specific. There is a large seam of shallow coal extending for about 100 miles outside Gillette, Wyoming. The coal generally dips to the west at about one degree. The coal that is deeper is not economical to get into. Montana has developed numeric standards for the two parameters of concern with the CBM, (1) salinity and (2) sodium absorption ratio. Wyoming only has a narrative standard, which states that the water quality cannot be of such quality that there will be a significant decrease in agricultural production. In some ways we believe that is a better approach than a straight numeric standard because you can adapt the effluent limits to the individual situation. You may have a situation where the soil is very compact, or really loose and you're going to have a different number. The problem is that you'rl~ fighting battles every time. In some cases, they are going to be more restrictive, or in some caSt:s less restrictive. We're doing it in a very labor intensive way. Two main concepts: (1) our relationship with Montana and how that is affecting us; and (2) our local situation within Wyoming. 3