Geology Reports⌕ Search

Geology topics

G.C. Huffman

Publications and source records attributed to G.C. Huffman.

12 recordsLinked to original sources
USGS2000

Simulation of ground water flow in the Glaciofluvial, Saginaw, Parma-Bayport, and Marshall Aquifers, Central Lower Peninsula of Michigan

A steady-state finite difference model was developed to simulate ground-water flow in four regional aquifers in Michigan’s Lower Peninsula. The Glaciofluvial, Saginaw, Parma-Bayport, and Marshall aquifers were simulated as layers 1 through 4, respectively, in the model. Separately calculated vertical conductances input to the model were used to simulate the intervening Till/“Red Beds”, Saginaw, and Michigan confining units, respectively. The model domain was laterally bound by a continuous specifiedhead boundary, formed from Lakes Michigan, Huron, St. Clair, and Erie, together with the St. Clair and Detroit River connecting channels. The model was developed to quantify regional ground-water flow in the aquifer systems using independently determined recharge estimates. The flow model showed that groundwater heads and flows in the Glaciofluvial aquifer are controlled by local stream stages and discharges, resulting in localized flow cells accounting for 95-percent of the overall model water budget. Simulation of recharge to an unspecified water table also enabled the estimation of ground-water discharge to three Great Lakes. A computer diskette contains all MODFLOW and MODFLOWP input files, as well as digital model surfaces and several Fortran processing routines used to construct the surfaces. The diskette also provides the data used for calibration and sensitivity analysis.

Michigan↗
USGS1996

Geohydrology and contamination at the Michigan Department of Transportation maintenance garage area, Kalamazoo County, Michigan

A leaking underground storage tank was removed from the Michigan Department of Transportation maintenance garage area in Kalamazoo County., Mich., in 1985. The tank had been leaking unleaded gasoline. Although a remediation system was operational at the site for several years after the tank was removed, ground-water samples collected from monitoring wells in the area consistently showed high concentrations of benzene, toluene. ethylbenzene, and xylenes--indicators of the presence of gasoline. The U.S. Geological Survey did a study in cooperation with the Michigan Department of Transportation, to define the geology, hydrology, and occurrence of gasoline contamination in the maintenance garage area. The aquifer affected by gasoline contamination is an unconfined glaci'a.l sand and gravel aquifer. The average depth to water in the study area is about 74.7 feet. Water-level fluctuations are small; maximum fluctuation was slightly more than 1 foot during August 1993-August 1994. Hydraulic conductivities based on aquifer-test data collected for the study and estimated by use of the Cooper-Jacob method of solution ranged from 130 to 144 feet per day. Ground water is moving in an east-southeasterly direction at a rate of about I foot per day. Leakage from perforated pipes leading from the underground storage tanks to the pump station was identified as a second source of gasoline contamination to saturated and unsaturated zones. The existence of this previously unknown second source is part of the reason that previous remediation efforts were ineffective. Residual contaminants in the unsaturated zone are expected to continue to move to the water table with recharge, except in a small area covered by asphalt at the land surface. The gasoline plume from the perforated pipe source has merged with that from the leaking underground storage tank, and the combined plume in the saturated zone is estimated to cover an area of 30,000 square feet. The combined plume is in the upper 20 feet of the saturated zone. The relative distribution of benzene, toluene, ethylbenzene, and xylenes indicate that factors such as sorption, solubility, and susceptibility to microbial degradation are affecting the movement of the combined plume. Given these factors, the plume is expected to move at a rate of less than 1 foot per day.

Michigan↗
USGS1986

Ground-water data for Michigan 1985

Water levels, locations, depths, and aquifers tapped are given for 113 observation wells. Tabulated data include extremes of water levels for calendar year 1985 and for the period of record, pumpage of most major ground-water users in the State, and water-quality data from selected wells. The largest reported user of ground-water, the city of Lansing, pumped 7.9 billion gallons from the Saginaw Formation and glacial deposits in 1985.

Michigan↗
USGS1983

Ground-water data for Michigan 1982

Water levels, locations, depths, and aquifers tapped are given for 117 observation wells. Tabulated data include extremes of water levels for 1982 and for the period of record, pumpage of most major ground-water users in the State, and quality data on selected wells. The largest reported user of ground-water, the city of Lansing, pumped 8.2 billion gallons from the Saginaw Formation and glacial deposits.

Michigan↗
USGS1981

Ground-water data for Michigan, 1980

The purpose of this report is to make available the 1980 records of water levels and related data for the principal aquifers of the State. This report is written for municipalities, industries, institutions, consultants, drillers, hydrologists and other people interested in the ground-water resources.

Michigan↗
USGS1977

Ground-water data for Michigan, 1976

The purpose of this report is to make available the records of water levels in principal aquifers of the State through 1976 and to compile related data, such as records of ground-water pumpage. Also included in the report are data on municipal, public, and industrial water-supply facilities. Records of water levels in areas of heavy pumpage and in areas where changes are principally due to natural influences are illustrated or tabulated to allow comparison between these types of water-level fluctuations. Water levels and related data provide a record for the evaluation of available ground-water supplies. The long-term records serve as a framework to which short-term records may be related. This report is written for persons, municipalities, industries, institutions, consultants, drillers, and hydrologists interested in the groundwater resources of the State.

Michigan↗
USGS1971

Summary of ground-water hydrological data in Michigan in 1970

The purpose of this report is to make available the records of groundwater levels in principal aquifers of the State through 1970 and to compile other related data, such as records of ground-water pumpage, data on municipal, public and industrial water-supply facilities, and the effects of precipitation on ground-water levels. Records of water levels in areas of heavy pumpage, and in areas where changes are principally from natural influences, are illustrated or tabulated to allow comparison between these types of water- level fluctuations. The water levels and related data provide a day-to-day record for the evaluation of available ground-water supplies. The long-term records serve as a framework to which short-term records may be related. This report is written for those persons, municipalities, industries, institutions, consultants, drillers, and hydrologists interested in the ground-water resources of the State.

Michigan↗
USGS1970

Summary of ground-water hydrological data in Michigan in 1968

The purpose of this report is to make available the records of groundwater levels in the principal aquifers of the State through 1968 and to compile other related data, such as records of ground-water pumpage, data on municipal, public and industrial water-supply facilities, and the effects of precipitation on ground-water levels. Records of water levels in areas of heavy pumpage and in areas where changes are principally from natural influences are illustrated or tabulated to allow comparison between these types of water-level fluctuations. The water-levels and related data provide a day-to-day record for the evaluation of available ground-water supplies. The long-term records serve as a framework to which short-term records may be related. This report is written for those persons, municipalities, industries, institutions, consultants, drillers and hydrologists interested in the groundwater resources of the State.

Michigan↗
USGS1970

Summary of ground-water hydrological data in Michigan in 1969

The purpose of this report is to make available the records of ground-water levels in the principal aquifers of the State through 1969 and to compile other related data, such as records of groundwater pumpage, data on municipal, public and industrial water-supply facilities, and the effects of precipitation on ground-water levels. Records of water levels in areas of heavy pumpage, and in areas where changes are principally from natural influences, are illustrated or tabulated to allow comparison between these types of water-level fluctuations. The water levels and related data provide a day-to-day record for the evaluation of available ground-water supplies. The long-term records serve as a framework to which short-term records may be related. This report is written for those persons, municipalities, industries, institutions, consultants, drillers, and hydrologists interested in the ground-water resources of the State.

Michigan↗
USGS1965

Summary of ground-water conditions in Michigan in 1964

The purpose of this report is to make available records of groundwater level changes in the principal aquifers of the State during 1964 and compile other related data, such as ground-water pumpage, data on municipal, public and industrial water supply facilities, and the effects of precipitation on ground-water levels. Records of water level changes in areas of heavy pumpage and in areas where changes are principally from natural influences are illustrated or tabulated (table 2) to allow comparison between these two types of water-level fluctuations. The water-level and related data prOvide a day-to-day evaluation of available ground-water supplies. These long-term records serve as a framework to which many short-term records collected during an intensive investigation may be related. This report is written for those persons, municipalities, industries, institutions, consultants, drillers and hydrologists interested in the_groundwater resources of the State.

Michigan↗