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represent a significant pollution risk because of the observed relatively small rate of discharge of mine water. The maximum observed discharge in recent yeazs has been reported as a trickle (possibly a few gallons per minute). The discharge has been observed to occur only when there has been recent surface runoff from rain or snowmelt. Apparently, surface runoff feeds the Bumped water in the old mine workings, periodically causing the water level in the mine to rise up high enough to dischazge out of the pipe that extends from the portal towazd the pond. From the portal pipe, the mine water dischazge collects in the pond and could pollute other waters if the pond discharged through its emergency spillway and if the mine water discharge volume comprised a large portion of the pond discharge. The mine water dischazge rate appears too small, however, to overcome the combined dilutional capacity of the water in the pond and the relatively large amount of runoff that would be necessary to cause the pond to discharge. During the Division's April 2001 inspection, the mine water dischazge was reported as a trickle and had pH of 3.6 and electroconductivity of 2600 nunhos/cm. The discharge flowed to the pond which contained a small pool of water and had pH of 5.1 and electroconductivity of 2000 mmhos/cm. The surface depression in the northwestern part of the site occasionally impounds surface runoff, resulting in a pool a few feet deep. This impoundment does not have an embankment and does not represent a safety or environmental hazard. The Coal Gulch site is not located neaz or above any urbanized areas, communities, occupied dwellings, schools, or other public or commercial buildings or facilities. Sediment and Erosion Control Function Most of the disturbed area is a flat valley bottom and is erosionally stable. Much of the runoff from the valley bottom is routed through the sediment control/mine discharge treatment pond. Some of the runoff from the valley bottom flows into the diversion ditch on the west side of the site. Runoff from a backfill slope east of the pond either flows into the pond or flows off-site directly into the ditch next to Highway 160. Gully erosion occurs where surface runoff has down-cut into the side slopes of diversion ditches on the west and east sides of the site, and on the steepest slopes of the backfill slope east of the pond. Sediment from gully erosion is routed to the ditch next to Highway 160. A sediment fan has been deposited near the middle of the flat valley bottom of the Coal Gulch site and appears to have come from the steep slope on the east side of the valley that extends up to the adjoining Arness-McGriffin Mine. Estimate of Continuing Safety, Health or Environmental Problems The Division believes that the safety, health, and environmental concerns at the Coal Gulch Mine are minimal and have been reduced to the extent possible. The site poses no imminent threats to human safety or the environment and none are expected to develop. Due to the location of the mine next to U.S. Highway 160, the site should be periodically inspected to ensure that there is no off-site impact from sediment transport and for monitoring the continuing function of the pond.