A low flow surface-water synoptic survey was completed throughout the Allegheny and Monongahela River basins on August 13-21, 1998. Of the 121 sites sampled, 119 sites were previously sampled in 1979-81 as part of the Coal Area Hydrology Studies established by the USGS in cooperation with the Office of Surface Mining. This historic sampling network was established to acquire and disseminate hydrologic information for the major coal areas of the Nation to aid mining companies and regulatory authorities in preparing and assessing permits. The data collected in 1998 will be compared to data collected in Areas 2, 3 and 5 in 1979-81 (Herb and others, 1981, 1981; Herb and others, 1983) to assess water-quality changes that have occurred in this region. The 121 synoptic sites were selected randomly and all sites were characterized by type and age of mining. The characterization was based on available coal-mining related databases in the region. A breakdown of the characterization follows:Deep Mining (only)
Two sampling strategies were used during this synoptic. Eighty-nine (89) standard sites were sampled for pH, specific conductance, and basic mine drainage (MD) indicators, including sulfate, chloride, and total and dissolved aluminum, manganese, and iron. Additionally, thirty-two (32) intensive sites were sampled to obtain more detailed water-quality data, including the standard site analyses plus calcium, magnesium, sodium, potassium, silica, fluoride, and dissolved solids. Field determinations for all sites included water discharge, pH, specific conductance, water temperature, and alkalinity. Also, chilled samples were sent to the USGS Ocala Service Unit for heated acidity determinations for all sites. Quality control included 16 replicate samples taken at 16 individual, randomly selected sites.
In addition, an ecological assessment was completed at the intensive sites. At each synoptic site a quantitative invertebrate sample was taken in riffle habitat following national protocols established for NAWQA. This included a 0.25 m square slack sampler with a 425 micron net and dolphin bucket (Cuffney and others, 1993, p. 21-22). Five samples were taken and composited per site. These samples were sent to the USGS National Water Quality lab for identification and enumeration. At each of the five sample sites per reach, instantaneous velocity at (0.6 of total depth), depth, embeddedness, and particle size were recorded. Stream width, bank width, canopy cover, and stream aspect were determined. Stream gradient was taken from topographic maps. Additionally, an embeddedness survey was conducted at each of the standard sites.
Detailed methodology and standardized protocols can be obtained by contacting our office and at the NAWQA Method and Guideline Protocol publications page. A map of the drainage basins and site locations of the standard and intensive synoptic sites is available for viewing: