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Daniel J. Fitzpatrick

Publications and source records attributed to Daniel J. Fitzpatrick.

4 recordsLinked to original sources

Geohydrologic characteristics and simulated response to pumping stresses in the Sparta aquifer in East-Central Arkansas

A finite difference digital model of the Sparta aquifer system in Arkansas was developed to aid in assessing the geohydrologic characteristics of the aquifer as well as the impact of withdrawals on water-level declines in the aquifer. The model consists of two layers. The Cockfield aquifer, represented by layer 1, was modeled as a constant head surface. The Sparta aquifer is represented by layer 2. The base of the Sparta aquifer was modeled as a no-flow boundary. The model boundaries to the north, south, and east in Mississippi were represented by specified heads, while boundaries to the west in Louisiana were represented as no flow. The model period of 1989 to 1985 was divided into 25 stress periods. Appropriate aquifer withdrawals were assigned to each stress period. Calibrated hydraulic conductivities of the Sparta aquifer, ranged from 1 to 35 ft/day. Calibrated hydraulic vertical conductivities of the Cook Mountain confining unit ranged from 0.0003 to 0.000009 ft/day. The calibrated storage coefficient of the aquifer was 0.0001. More than 80% of the recharge to the aquifer came from vertical leakage and from direct recharge on the outcrop. Greater than 90 % of outflow from the aquifer was from pumpage or leakage to rivers. Theoretical pumping schemes to the year 2005 indicated that virtually no change to the potentiometric surface occurred when 1985 pumping rates were extended to 2005. Doubling of pumpage over the entire study area resulted in additional water-level declines of up to 130 ft.

Water-Resources Investigations Report

Altitude of the potentiometric surface and changes in water levels in the Sparta-Memphis aquifer in eastern and southern Arkansas, spring 1986

The Sparta-Memphis aquifer is a major source of industrial and public water supplies as well as a source of water for agricultural purposes in eastern and south-central Arkansas. The potentiometric-surface map for this aquifer, compiled from wastewater level measurements made during spring 1986, indicates a generally eastward and southward hydraulic gradient. The potentiometric surface also shows three major cones of depression resulting from groundwater withdrawals for industrial and public supplies; one centered in Columbia County, one in Union County, and one in Jefferson County. The water level change maps for the Sparta-Memphis aquifer for the period between spring 1981 and spring 1986 show large areas of both rise and decline in water levels across the study area. Largest rises occurred in parts of Jefferson, Columbia, and Phillips Counties, whereas largest declines occurred in parts of Union County. (USGS)

Water-Resources Investigations Report

Maps showing altitude of the potentiometric surface and changes in water level of the Sparta sand and Memphis sand aquifers in Eastern Arkansas, spring 1983

The Sparta Sand and the Memphis Sand aquifers are a major source of industrial and public water supply and a minor but locally significant source of water for agricultural purposes in eastern and south-central Arkansas. The potentiometric surface map for this aquifer, compiled from water-level measurements made during the spring of 1983, indicates a generally southward potentiometric gradient. The potentiometric surface also illustrates the existence of three major cones of depression; one centered in Columbia County, one in Union County, and one in Jefferson County. Within the cones of depression, the majority of water withdrawn is utilized for industrial and public supply. The water-level change map for the Sparta Sand and the Memphis aquifer for the period between the springs of 1982 and 1983 shows overall a rise in water levels across the study area, including the cones of depression in Jefferson and Union Counties; however, water levels within the cone depression in Columbia County generally declined.

Arkansas

Hydrologic data from monitoring of saline-water intrusion in the Cape Coral area, Lee County, Florida

As a result of declining water levels and saline-water intrusion in the Cape Coral area, the U.S. Geological Survey in cooperation with the City of Cape Coral established a monitoring well network in Cape Coral and adjacent areas in 1978-79. The network was designed to provide indication of lateral movement of saline water in the upper part of the Hawthorn Formation; to provide trends in water levels; and to provide background data from: (1) the aquifer in the upper part of the Hawthorn Formation; (2) the aquifer in the lower part of the Hawthorn Formation and upper part of the Tampa Limestone; and (3) the surficial aquifer. The monitoring well network consists of 77 wells. Data collected in this network since 1978, as well as data collected from selected wells in the network prior to 1978, are compiled in this report. These data include water-quality data from 69 wells, water-level data from 29 wells, and lithologic logs from 18 wells. Other data compiled in this report include municipal pumpage and rainfall data supplied by the City of Cape Coral.

Florida