Charles A Cravotta, III, PhD, PG (Former Employee)

This report, prepared in cooperation with the Pennsylvania Department of Environmental Protection (PaDEP), the Eastern Pennsylvania Coalition for Abandoned Mine Reclamation, and the Dauphin County Conservation District, provides estimates of water budgets and groundwater volumes stored in abandoned underground mines in the Western Middle Anthracite Coalfield, which encompasses an area of...

Phosphorus from natural and human sources is likely to be discharged from groundwater to streams in certain geochemical environments. Water-quality data collected from 1991 through 2007 in paired networks of groundwater and streams in different hydrogeologic and land-use settings of the Piedmont, Blue Ridge, and Valley and Ridge Physiographic Provinces in the eastern United States were...

To investigate the interaction between methanogens and iron-containing minerals in anoxic environments, we conducted batch culture experiments with Methanosarcina barkeri in a phosphate-buffered basal medium (PBBM) to bioreduce structural Fe(III) in goethite with hydrogen as the sole substrate. Fe(II) and methane concentrations were monitored over the course of the bioreduction...

Excess phosphorus (P) inputs from human sewage, animal feeding operations, and nonpoint source discharges to the environment have resulted in the eutrophication of sensitive receiving bodies of water such as the Great Lakes and Chesapeake Bay. Phosphorus loads in wastewater discharged from such sources can be decreased by conventional treatment with iron and aluminum salts but these

Treatment with caustic chemicals typically is used to increase pH and decrease concentrations of dissolved aluminum, iron, and/or manganese in largevolume, metal-laden discharges from active coal mines. Generally, aluminum and iron can be removed effectively at near-neutral pH (6 to 8), whereas active manganese removal requires treatment to alkaline pH (~10). The treatment cost depends...

A variety of passive and semi-passive treatment systems were constructed by state and local agencies to neutralize acidic mine drainage (AMD) and reduce the transport of dissolved metals in the upper Swatara Creek Basin in the Southern Anthracite Coalfield in eastern Pennsylvania. To evaluate the effectiveness of selected treatment systems installed during 1995–2001, the US Geological...