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Mary Martin

Publications and source records attributed to Mary Martin.

6 recordsLinked to original sources
USGS1998

Ground-water flow in the New Jersey Coastal Plain

Ground-water flow in 10 aquifers and 9 intervening confining units of the New Jersey Coastal Plain was simulated as part of the Regional Aquifer System Analysis. Data on aquifer and confining unit characteristics and on pumpage and water levels from 1918 through 1980 were incorporated into a multilayer finite-difference model. The report describes the conceptual hydrogeologic model of the unstressed flow systems, the methods and approach used in simulating flow, and the results of the simulations.

Delaware, New Jersey↗
USGS1987

Ground-water-withdrawal and water-level data used to simulate regional flow in the major coastal plain aquifers of New Jersey

The report documents groundwater withdrawal and level data for the major aquifers of the New Jersey Coastal Plain. These data have been used in the Regional Aquifer System Analysis flow model of 10 major aquifers in the New Jersey Coastal Plain. Groundwater withdrawal data from more than 1,400 wells are tabulated by year for 1956 through 1980. Total yearly withdrawals for 171 public supply and industrial purveyors for 1918 through 1955 are documented. Best estimates are given for percentages of total withdrawals by aquifer for the 1918 through 1955 data. Groundwater withdrawal data is also tabulated yearly from 1918 through 1980 by county for each aquifer. Long-term hydrographs for 89 Coastal Plain wells provide information on water level fluctuations over time. Potentiometric maps showing earliest recorded water levels in Coastal Plain aquifers delineate prepumping conditions. Groundwater withdrawals from the Coastal Plain have increased from less than 50 million gal/day in 1918 to more than 350 million gal/day in 1980. In response to these increased withdrawals, groundwater levels have been steadily declining. In some areas where wells once flowed freely, water levels are now 100 to 200 ft below land surface. (USGS)

Water-Resources Investigations Report↗
USGS1984

Simulated ground-water flow in the Potomac aquifers, New Castle County, Delaware

Flow in three aquifers of the Potomac Formation in New Castle County, Delaware, was simulated. Results of the calibrated flow model show the maximum transmissivity of the lower aquifer is between 1,000 and 1,500 square feet per day; the middle aquifer, between 3,000 and 3,500 square feet per day; and the upper aquifer, between 5,000 and 6,000 square feet per day. Vertical leakance values for the three confining beds are similar and range 1 x 10 to the (1-8) power per day in downdip areas and .01 per day in subcrop areas. A storage coefficient of 0.00056 was used for each aquifer. A specific storage value of 0.000006 per foot was used for each confining bed. Estimated storage coefficients were not changed during calibration. Changes in water levels resulting from five scenarios of future pumpage were evaluated. Results of these simulations show: (1) the reduction in pumpage at Amoco causing a 120 foot local recovery of heads; (2) water levels generally will change less than 25 feet if there is no change in pumpage; (3) proposed pumpage in western Delaware may cause drawdowns below the tops of the aquifers; and (4) expected increases in pumpage would cause the greatest head decline, about 40 feet, in the lower aquifer at Getty. (USGS)

Water-Resources Investigations Report↗