Two environmental groups say an unlined coal ash pond just outside of Harrodsburg, Ky., is leaking toxic contaminants into the surrounding surface and groundwater, causing a potential threat to nearby residents.The coal ash is produced by the the E.W. Brown power plant, owned by Louisville Gas and Electric and operated by Kentucky Utilities. The Sierra Club and EarthJustice said a previously unreleased document from the Kentucky Department of Environmental Protection shows that it's discharging a “highly contaminated ‘orange-colored’ water” through a drain pipe.LG&E has not yet responded to requests for comment. We'll update with their response when we get it.Update 5:35 p.m.: Here's LG&E's response: We’ve been in communication with the Division of Water about the drain tiles in the ash pond dam structure. We are extending our full cooperation in addressing the conditions. We've assessed the situation and it does not impact public drinking water sources or Lake Herrington. As part of our previously submitted landfill permit, we are implementing a plan of action to construct a new catch basin and pump system that will connect to our existing water treatment processing system and through an existing Kentucky Department of Environmental Protection monitoring point. We’re committed to strict compliance with applicable environmental laws and regulations, and minimizing the impact of our operations on the surrounding community.Coal ash is the toxic byproduct of burning coal and contains heavy metals and chemicals, such as mercury, arsenic and boron.“This is a site that should have never held coal ash in the first place, or if it did it should have been in a secure landfill with modern technologies," said Nachy Kanfer is the deputy director of the Sierra Club’s central region. "LG&E knows this is an unlined pit and L&GE knows this is an inappropriate place to store coal ash and as a result we have this discharge taking place.”The pond contains at least 26 million tons of coal ash and is located a quarter of a mile from the Herrington Lake recreational area, the Sierra Club alleges.“The coal ash storage facility has already contaminated the ground water below," Kanfer says. "We found evidence from the Kentucky DEP knows of nine different springs and surface water sampling points with high levels of boron contamination north of the site, two of which exceed EPA health levels for children.”The pond is located a quarter of a mile mile from the Herrington Lake recreational area .