Stack emissions are continuously monitored, as are all water discharges, and regulated under state and federal permits by the Pennsylvania Department of Environmental Protection. Nitrogen Oxides are controlled by combustion temperature control and by ammonia injection into the gas stream. Under the 2003 NOx transport rules, the plant has been able to market its NOx emission offsets to its ultra low NOx emission characteristics. About 320 tons of ash per day are produced from the combustion of waste coal, which is back hauled to the fuel sources for neutralization of acidic mining areas that are subject to remediation processes. Investigation of other uses for combustion ash is ongoing in the areas of cement component/road manufacture and agricultural lime, all of which are proving both feasible and safe.