MONITORING WATER QUALITY FOR HISTORICAL AND EMERGING IMPACTS, WASHINGTON COUNTY, PA

As pressure increases for energy resource exploration and extraction, water quality must be regarded with the utmost scrutiny, especially in areas of prior environmental stress. In southwestern Pennsylvania, a project is underway to acquire baseline water quality and monitor changes due to current impacts. Located near the California Borough, PA, data have been collected from local tributaries of the Monongahela River, the primary drinking water source for towns along its course, including Pittsburgh. Challenges to water quality exist due to historic coal mining, increased development, and the potential impact of shale gas exploration and extraction within the local watersheds. It is impossible to attain a water quality background before historic coal mining began, but the opportunity remains to acquire background data before drilling activities mature in the area. The area of study, primarily within Washington County, is characterized by hill and valley topography with numerous streams and a humid continental climate. Land use and cover varies from localized, sporadic commercial and residential development, especially along the Monongahela River, intermixed with agriculture and forest. Our target stream, Pike Run, responds quickly to precipitation, generating concern for the ability of the stream to dilute contaminants, especially during low-water level times between rain events. Conductivity, temperature, water level, and precipitation data in four different watersheds were collected. Our primary variable, conductivity, tells little by itself, but may indicate stresses to the health of a stream, especially when compared to flow (and precipitation). Conductivity values for Pike Run have been measured as high as 1200 µS/cm and have averaged 680 µS/cm for the last 14 months. Based on EPA recommendations, these consistently high values are troubling compared to other streams. When considering precipitation events, conductivity decreases, indicating normal dilution. However, rapid rebound of values to above-acceptable levels is the norm.