Maryland Department of Natural Resources

Staff Profile

David C. Andreasen (Hydrogeology Program Chief)

B-3 Tawes State Office Bldg.
580 Taylor Avenue
Annapolis, MD 21401
(410) 260-8814
Email



Current Projects

  • Monitoring potential land subsidence related to groundwater withdrawals in Maryland's coastal plain aquifer system

    • Past Projects

  • Developing GIS system for visualizing groundwater-quality data using multiple, cross agency databases
  • Mapping the distribution of radionuclides (polonium-210, radium) in groundwater
  • Hydrogeology surrounding a Confined Aquatic Disposal site for placement of dredge material
  • Potentiometric surface maps for the Aquia, Magothy, Upper Patapsco, Lower Patapsco, and Patuxent aquifers
  • GIS system for storing and displaying hydrogeologic data for Maryland's coastal plain aquifer system (Maryland Coastal Plain Aquifer Information System)
  • Ground-water-flow models (MODFLOW) for water-supply management in the coastal plain aquifer system
  • Optimization modeling to evaluate efficiency of pumping schemes
  • Exploration through test-drilling programs in coastal plain sediments
  • Mapping saltwater intrusion
  • Estimating areas contributing recharge to well fields

    Education

    B.S., University of Maryland, College Park, Geology

    Reports

    Andreasen, D.C., and Hansen, H.J., 1987, Summary of hydrogeologic data from a test well (1,725 ft.) drilled in Tuckahoe State Park, Queen Anne’s County, Maryland: Maryland Geological Survey Open- File Report No. 87-02-3, 47 p.

    Mack, F.K., and Andreasen, D.C., 1991, Geohydrologic data for the Coastal Plain sediments underlying Broadneck Peninsula, Anne Arundel County, Maryland: Maryland Geological Open-File Report No. 92-02-6,70 p.

    Fleck, W.B., Andreasen, D.C., 1997, Geohydrologic framework, ground-water quality and flow, and brackish-water intrusion in east-central Anne Arundel County, Maryland, with a section on Potential for brackish-water intrusion in the Aquifer in the Annapolis area by Barry S. Smith: Maryland Geological Survey Report of Investigations No. 62, 136 p.

    Andreasen D.C., and Smith, B.S., 1998, Hydrogeology and simulation of ground-water flow in the Upper Wicomico River Basin and estimation of contributing areas of the City of Salisbury well fields, Wicomico County, Maryland: Maryland Geological Survey Report of Investigations No. 65, 87 p.

    Andreasen, D.C., and Mack, F.K., 1998, Evaluation of the geohydrology and water-supply potential of the lower Patapsco and Patuxent aquifers in the Indian Head-Bryans Road area, Charles County, Maryland: Initial Findings: Maryland Geological Survey U.S. Geological Survey Open-File Report No. 98-02-9, 50 p.

    Andreasen, D.C, 1999, Geohydrology and water-supply potential of the lower Patapsco aquifer and Patuxent aquifers in the Indian Head-Bryans Road area, Charles County, Maryland: Maryland Geological Survey Report of Investigations No. 69, 119 p.

    Andreasen, D.C., and Fewster, T.B, 2001, Estimation of areas contributing recharge to selected public-supply Wells in designated Metro Core areas of Upper Wicomico River and Rockawalking Creek Basins, Maryland: Maryland Geological Survey Open-File Report No. 2001-0214, 28 p.

    Andreasen, D.C., 2002, Hydrogeology, water quality, and water-supply potential of the Aquia and Magothy aquifers in Southern Anne Arundel County, Maryland: Maryland Geological Survey Report of Investigations No. 74, 110 p.

    Andreasen, D.C., 2003, Optimization of ground-water withdrawals in the Lower Patapsco aquifer, Waldorf, Maryland: Maryland Geological Survey Open-File Report 2003-02-17, 51 p.

    Andreasen, D.C., 2004, Optimization of ground-water withdrawals from the Lower Patapsco and Patuxent aquifers in the Bryans Road service area, Charles County, Maryland: Maryland Geological Survey Administrative Report, 24 p.

    Andreasen, D.C., 2004, Optimization of ground-water withdrawals from the Lower Patapsco and Patuxent aquifers in the Bryans Road Service Area, Charles County, Maryland: Maryland Geological Survey Administrative Report, 21 p.

    Andreasen, D.C., 2006, Optimization of ground-water withdrawals from the Upper Patapsco, Lower Patapsco, and Patuxent aquifers in the Anne Arundel County, Maryland: Maryland Geological Survey Report of Investigations No. 77, 107 p.

    Duigon, M.T., Andreasen, D.C, Curtin, S.E., Gerhart, J.M., Smigaj, M.J., Yeskis, D.J., and Smith, M.A., 2006, The Maryland State observation-well network—Recommendations for the design of an optimum network: Maryland Geological Survey Open-File Report (unpublished)

    Staley, A.W., Bell, S.C., Andreasen, D.C., and Bolton, D.W., 2009, Hydrogeologic data for the Coastal Plain sediments northwest of Ft. Meade, Maryland: Maryland Geological Survey Administrative Report 09-02-04, 56 p.

    Raffensperger, J.R., Fleming, B.J., Banks, S.L., Horn, M.A., Nardi, M.R., and Andreasen, D.C., 2010, Simulation of groundwater flow to assess future withdrawals associated with Base Realignment and Closure (BRAC) at Fort George G. Meade, Maryland: U.S. Geological Survey Scientific Investigations Report 2010-5186, 48 p.

    Drummond, D.D., Andreasen, D.C., Staley, A.W., and Bolton, D.W., 2011, Hydrogeologic data from eight test- well sites on the Maryland Eastern Shore: Maryland Geological Survey Basic Data Report No. 23, in preparation.

    Curtin, S.E., Andreasen, D.C., and Staley, A.W., 2012, Potentiometric surface and water-level difference maps of selected confined aquifers of Southern Maryland and Maryland’s Eastern Shore, 1975–2011: U.S. Geological Survey Scientific Investigations Report 2012–5165, 36 p.

    Andreasen, D.C., Achmad, G., and Staley, A.W., 2012, Maryland Coastal Plain aquifer information system: Hydrogeologic framework: Maryland Geological Survey Open-File Report No. 12-02-20, 121 p.

    Andreasen, D.C., Keeney, L., and Bolton, D.W., 2014, Hydrogeology of the Port of Baltimore Confined Aquatic Disposal Pilot Project Area, Masonville, Maryland: Maryland Geological Survey Open-File Report 14-02-01, 43 p.

    Bolton, D.W., Quinn, H.A., and Andreasen, D.C., 2014, Compilation and review of GIS-based ground-water quality data from multiple databases for Garrett County, Maryland: Maryland Geological Survey Administrative Report 14-02-02, 14 p.

    Staley. A.W., Andreasen, D.C., and Curtin, S.E., 2014, Potentiometric surface and water-level difference maps of selected confined aquifers in Southern Maryland and Maryland's Eastern Shore, 1975-2013: Maryland Geological Survey Open-File Report 14-02-02, 29 p.

    Andreasen, D.C., 2015, Preliminary investigation of elevated radioactivity in groundwater in Charles County, Maryland: Maryland Geological Survey Open-File Report 15-02-02, 70 p.

    Andreasen, D.C., 2016, Establishment of a land subsidence-monitoring network to assess the potential effects of groundwater withdrawals in Southern Maryland: Maryland Geological Survey Open-File Report 16-02-01, 38 p.

    Andreasen, D.C., 2016, Land subsidence monitoring at Arnold, Broad Creek, and Crofton Meadows well fields in Anne Arundel County, Maryland: 2016 survey: Maryland Geological Survey Administrative Report 16-02-01, 13 p.

    Andreasen, D.C., 2016, Hydrographs and tables showing ground-water level records for selected observation wells in Anne Arundel County, Maryland and hydrograph showing surface-water flow in Sawmill Creek, 2016 Report: 2016 survey: Maryland Geological Survey Administrative Report 16-02-02, 46 p.

    Pope, J.P., Andreasen, D.C., McFarland, E.R., and Watt, M.K., 2016, Digital elevations and extents of regional hydrogeologic units in the Northern Atlantic Coastal Plain aquifer system from Long Island, New York, to North Carolina: U.S. Geological Survey Data Series 996, 28 p., http://dx.doi.org/10.3133/ds996.

    Staley, A.W., Andreasen, D.C., and Curtin, S.E., 2016, Potentiometric surface and water-level difference maps of selected confined aquifers in Southern Maryland and Maryland's Eastern Shore, 1975-2015: Maryland Geological Survey Open-File Report 16-02-02, 30 p.

    Andreasen, D.C., 2017, Effects of projected (2086) groundwater withdrawals on management water levels and domestic wells in Anne Arundel County, Maryland: Maryland Geolgical Survey Open-File Report 17-02-01, 19 p.

    Andreasen, D.C., 2017, Land subsidence monitoring at Arnold, Broad Creek, and Crofton Meadows wells fields in Anne Arundel County, Maryland: Fall, 2016 survey:Maryland: Maryland Geolgical Survey Administrative Report 17-02-04, 19 p,

    Andreasen, D.C., 2018, Land subsidence monitoring to assess potential effects of groundwater withdrawals from coastal plain aquifers in Maryland: Fall, 2017 survey: Maryland Geological Survey Administrative Report 18-02-03, 19 p.

    Gemperline, J.M., VanDerwerker, T.J., and Andreasen, D.C., 2018, Effects of increased withdrawals from the Aquia aquifer on the Mayo Peninsula, Anne Arundel County, Maryland with an evaluation of water quality: Maryland Geological Survey Report of Investigations 84, 57 p.

    Journal Papers

    Andreasen, D.C., and Fleck, W.B., 1997, Use of bromide:chloride ratios to differentiate potential sources of chloride in a shallow, unconfined aquifer affected by brackish-water intrusion: Hydrogeology Journal, vol. 5, no 2., pp. 17-26

    Plummer, L.N., Eggleston, J.R., Andreasen, D.C., Raffensperger, J.P., Hunt, A.G., and Casile, G.C., 2012, Old groundwater in parts of the upper Patapsco aquifer, Atlantic Coastal Plain, Maryland, USA: Evidence from radiocarbon, chlorine-36 and helium-4: Hydrogeology Journal, Vol. 20, No. 7

    Andreasen, D.C., Nardi, M.R., Staley, A.W., Achmad, Grufron, and Grace, J.W., 2016, The Maryland Coastal Plain Aquifer Information System: A GIS-based tool for assessing groundwater 8 resources, in Wessel, G.R., and Greenberg, J.K., eds., Geoscience for the Public Good and Global Development: Toward a Sustainable Future: Geological Society of America Special Paper 520, p. SPE520-15.

    Miller, K.G., Browning, J.V., Sugarman, P.J., Monteverde, D.H., Andreasen, D.C., Lombardi, C., Thornburg, J., Ying Fan, and Kopp, R.E., 2017, Lower to mid-Cretaceous sequence stratigraphy and characterization of co2 storage potential in the mid-Atlantic U.S. Coastal Plain: Journal of Sedimentary Research, v. 87, pp. 609–629

    Potentiometric Surface Maps

    PRELIMINARY MAP SHOWING THE POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1984. Mack, F.K., Wheeler, J.C., Curtin, S.E., and Andreasen, D.C., U.S. Geological Survey Water-Resources Investigations Report No. 85-4338, 1985, 1 p.

    THE POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER, 1985. Mack, F.K., Wheeler, J.C., Curtin, S.E., and Andreasen, D.C., U.S. Geological Survey Water Resources Investigations Report No. 87-4029, 1987, 1 p.

    POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND DURING THE FALL OF 1986. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigations report No. 87-4214, 1987, 1 p.

    POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND DURING THE FALL OF 1987. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigation Report No. 89-4012, 1989, 1 p.

    POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND DURING THE FALL OF 1988. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigations Report No. 90-4037, 1990, 1 p.

    POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1989. Mack, F.K., Curtin, S.E., Andreasen, D.C., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigations Report No. 91-4094, 1991, 1 p.

    POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1990. Mack, F.K., Curtin, S.E., Andreasen, D.C., and Wheeler, J.C., U.S. Geological Survey Open-File Report No. 92-459, 1992, 1 p.

    POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1991. Curtin, S.E., Andreasen, D.C., and Mack, F.K., U.S. Geological Survey Open-File Report No. 93-652, 1993, 1 p.

    POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1993. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 94-390, 1994, 1 p.

    POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1994. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 95-743, 1995, 1 p.

    POTENTIOMETRIC SURFACE OF THE AQUIA AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1995. Curtin, S.E., Andreasen, D.C., and Mack. .K., U.S. Geological Survey Open-File Report No. 96-620, 1996, 1 p.

    PRELIMINARY MAP SHOWING THE DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE AQUIA AQUIFER OF SEPTEMBER 1982 AND SEPTEMBER 1984 IN SOUTHERN MARYLAND. Mack, F.K., Wheeler, J.C., Curtin, S.E., and Andreasen, D.C., U.S. Geological Survey Water Resources Investigations Report No. 85-4339, 1985, 1 p.

    DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE AQUIA AQUIFER IN THE SPRING OF 1979 AND FALL OF 1986 IN SOUTHERN MARYLAND. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigations Report No. 87-4215, 1987, 1 p.

    THE DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE AQUIA AQUIFER OF SEPTEMBER 1986 AND SEPTEMBER 1988 IN SOUTHERN MARYLAND. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigations Report No. 90-4039, 1990, 1 p.

    THE DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE AQUIA AQUIFER OF SEPTEMBER 1982 AND SEPTEMBER 1990 IN SOUTHERN MARYLAND. Mack, F.K., Curtin, S.E., Andreasen, D.C, and Wheeler, J.C., U.S. Geological Survey Open-File Report No. 92-463, 1992, 1 p.

    THE DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE AQUIA AQUIFER OF SEPTEMBER 1982 AND SEPTEMBER 1993 IN SOUTHERN MARYLAND. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 94-394, 1994, 1 p.

    THE DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE AQUIA AQUIFER OF SEPTEMBER 1982 AND SEPTEMBER 1995 IN SOUTHERN MARYLAND. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 96-624, 1995, 1 p

    THE POTENTIOMETRIC SURFACE OF THE MAGOTHY AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1985. Mack, F.K., Wheeler, J.C., Curtin, S.E., and Andreasen, D.C., U.S. Geological Survey Water Resources Investigations Report No. 87-4025, 1987, 1 p.

    POTENTIOMETRIC SURFACE OF THE MAGOTHY AQUIFER IN SOUTHERN MARYLAND DURING THE FALL OF 1986. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C¸ U.S. Geological Survey Water Resources Investigations Report No. 87-4216, 1987, 1 p.

    POTENTIOMETRIC SURFACE OF THE MAGOTHY AQUIFER IN SOUTHERN MARYLAND DURING THE FALL OF 1987. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigations Report No. 89-4013, 1989, 1 p.

    POTENTIOMETRIC SURFACE OF THE MAGOTHY AQUIFER IN SOUTHERN MARYLAND DURING SEPTEMBER 1988. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigations Report No. 90-4040, 1990, 1 p.

    POTENTIOMETRIC SURFACE OF THE MAGOTHY AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1989. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigations Report No. 91-4093, 1991, 1 p.

    POTENTIOMETRIC SURFACE OF THE MAGOTHY AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1990. Mack, F.K., Curtin, S.E., Andreasen, D.C., and Wheeler, J.C., U.S. Geological Survey Open-File Report No. 92-460, 1992, 1 p.

    POTENTIOMETRIC SURFACE OF THE MAGOTHY AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1991. Curtin, S.E., Andreasen, D.C., and Mack, F.K., U.S. Geological Survey Open-File Report No. 93-653, 1993, 1 p.

    POTENTIOMETRIC SURFACE OF THE MAGOTHY AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1993. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 94-391, 1994, 1 p.

    POTENTIOMETRIC SURFACE OF THE MAGOTHY AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1994. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 95-744, 1995, 1 p.

    POTENTIOMETRIC SURFACE OF THE MAGOTHY AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1995. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 96-621, 1996, 1 p.

    THE DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE MAGOTHY AQUIFER OF SEPTEMBER 1982 AND SEPTEMBER 1984 IN SOUTHERN MARYLAND. Mack, F.K., Wheeler, J.C., and Curtin, S.E., Andreasen, D.C., U.S. Geological Survey Water Resources Investigations Report No. 85-4337, 1985, 1 p.

    THE DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE MAGOTHY AQUIFER IN THE FALL OF 1975 AND FALL OF 1986 IN SOUTHERN MARYLAND. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigations Report No. 87-4217, 1987 1 p.

    THE DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE MAGOTHY AQUIFER OF SEPTEMBER 1986 AND SEPTEMBER 1988 IN SOUTHERN MARYLAND. Mack, F.K., Andreasen, D.C., Curtin, S.E., and Wheeler, J.C., U.S. Geological Survey Water Resources Investigations Report 90-4038, 1990, 1 p.

    THE DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE MAGOTHY AQUIFER OF SEPTEMBER 1975 AND SEPTEMBER 1990 IN SOUTHERN MARYLAND. Mack, F.K., Curtin, S.E., Andreasen, D.C., and Wheeler, J.C., U.S. Geological Survey Open-File Report No. 92-464, 1992, 1 p.

    THE DIFFERENCE BETWEEN THE POTENTIOMETRIC SURFACES OF THE MAGOTHY AQUIFER OF SEPTEMBER 1975 AND SEPTEMBER 1993 IN SOUTHERN MARYLAND. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 94-395, 1994, 1 p.

    POTENTIOMETRIC SURFACE OF THE UPPER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1990. Mack, F.K., Curtin, S.E., Andreasen, D.C., and Wheeler, J.C., U.S. Geological Survey Open-File Report No. 92-461, 1992, 1 p.

    POTENTIOMETRIC SURFACE OF THE UPPER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1991. Curtin, S.E., Andreasen, D.C., and Mack, F.K., U.S. Geological Survey Open-File Report No. 93-654, 1993, 1 p.

    POTENTIOMETRIC SURFACE OF THE UPPER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1993. Curtin, S.E., Mack F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 94-392, 1994, 1 p.

    POTENTIOMETRIC SURFACE OF THE UPPER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1994. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 95-745, 1995, 1 p.

    POTENTIOMETRIC SURFACE OF THE UPPER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1995. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 96-622, 1996, 1 p.

    POTENTIOMETRIC SURFACE OF THE LOWER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1990. Mack, F.K., Curtin, S.E., Andreasen, D.C., and Wheeler, J.C., U.S. Geological Survey Open-File Report No. 92-462, 1992, 1 p.

    POTENTIOMETRIC SURFACE OF THE LOWER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1991. Curtin, S.E., Andreasen, D.C., and Mack, F.K., U.S. Geological Survey Open-File Report No. 93-655, 1993, 1 p.

    POTENTIOMETRIC SURFACE OF THE LOWER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1994. Curtin, S.E., Andreasen, D.C., and Mack, F.K., U.S. Geological Survey Open-File Report No. 95-746, 1995, 1 p.

    POTENTIOMETRIC SURFACE OF THE LOWER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1995. Curtin, S.E., Andreasen, D.C., and Mack, F.K., U.S. Geological Survey Open-File Report No. 96-623, 1996, 1 p.

    POTENTIOMETRIC SURFACE OF THE LOWER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1993. Curtin, S.E., Mack, F.K., and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 94-393, 1994, 1 p.

    POTENTIOMETRIC SURFACE OF THE LOWER PATAPSCO AQUIFER IN SOUTHERN MARYLAND, SEPTEMBER 1994. Curtin, S.E. and Andreasen, D.C., U.S. Geological Survey Open-File Report No. 95-746, 1995, 1 p.