Hydrologic assessment, Eastern Coal Province Area 23, Alabama

Abstract

The Eastern Coal Province is divided into 24 separate hydrogic reporting areas. The division is based on hydrologic factors, location, size, and mining activity. Hydrologic units (drainage basins) or parts of units are combined to form each area. Area 23 is located at the southern end of the Eastern Coal Province, in the Mobile River basin, includes the Warrior, Cahaba, and edges of the Plateau coal fields in Alabama, and covers an area of 4,716 square miles. Each report is designed to be useful to mine owners and operators and consulting engineers by presenting information about existing hydrologic conditions and identification of sources of hydrologic information. General hydrologic information is presented in a-brief text and illustrations on a single water-resources related topic. Area 23, this report, is underlain by the Coker and Pottsville Formations and the pre-Pennsylvanian rocks. The Pottsville Formation contains coal beds and is overlain by the Coker Formation in the western and southern parts of the area. The pre-Pennsylvanian rocks crop out in two northeast-southwest trending belts or ridges along and near the eastern boundary where folding and faulting is common. The outcrop of rocks along the western ridge forms the divide between the Warrior and the Cahaba coal fields. The area lies in four river basins, the Black Warrior, Cahaba, Sipsey, and Buttahatchee. The Black Warrior River drains most of the Pottsville Formation with some outliers of the Coker Formation in the southern edge. The Sipsey and Buttahatchee Rivers are incised into the Pottsville Formation but drain, for the most part, the overlying Coker Formation. The Cahaba River flows over the Pottsville Formation in a valley between two ridges of pre-Pennsylvanian rocks. Area 23 has a moist temperate climate with an annual average rainfall of 54 inches and the majority of the area is covered by forest. The soils have a high erosion potential when the vegetative cover is removed. public supplies. The principal uses of water are for cooling water for thermoelectric power generation and for industrial and municipal supplies for the city of Birmingham. The U.S. Geological Survey operates a network of hydrologic data collection stations to monitor the streamflow and groundwater conditions. This network includes data for 180 surface-water stations and 49 groundwater observation wells. These data include rate of flow, water levels, and water-quality parameters. These data are available from computer storage through the National Water Data Exchange (NAWDEX). Hydrologic problems relating to surface mining are (1) erosion and sedimentation, (2) decline in groundwater levels, and (3) degradation of water quality. Average annual sediment yields can increase by four magnitudes in surface mined areas from 20 (tons/mi2)/yr from areas not affected by mining to 300,000 (tons/mi2)/yr from mined areas. Sediment yields increase drastically when vegetation is removed from the highly erosive soils and from unregulated surface mining operations. Decline in groundw...

Geohydrology and susceptibility of major aquifers to surface contamination in Alabama; area 6

“…The Pottsville Formation consists chiefly of sandstone, conglomerate, siltstone, and shale with beds of coal and underclay. It strikes northwest and dips to the southwest at 30 to 200 ft/mi (feet per mile) (Harkins and others, 1980). Large water supplies generally are not available from the Pottsville Formation and no municipal wells tap the Pottsville within the study area.…”

Hydrology of potential mining areas in the Warrior coal field, Alabama

“…Recent reports from this and related investigations provide information on the water resources of the area. Reports by Knight and Newton (1977), Puente and Newton (1979), and Harkins and others (1980) provide information describing water-related impacts resulting from surface mining in the Warrior Coal Field. Puente and others (1980) defined baseline conditions and basic hydrologic processes in the area of study and Puente and others (1981 ) described methods of estimating hydrologic conditions in mined and unmined areas in the Warrior coal field.…”

Hydrology of area 4, Eastern Coal Province, Pennsylvania, Ohio, and West Virginia

“…In low concentrations, trace elements provide a source of nutrients to plants and animals. As concentrations increase some trace elements can become toxic (Harkins, 1980). Although high concentrations may occur naturally, they are usually associated with the discharge of industrial wastes.…”