Geology Reports⌕ Search

Geology topics

Allan D. Randall

Publications and source records attributed to Allan D. Randall.

At least 19 recordsLinked to original sources

Transmissivity estimated from brief aquifer tests of domestic wells and compared with bedrock lithofacies and position on hillsides in the Appalachian Plateau of New York

Procedures for undertaking and analyzing recovery from aquifer tests of 13 to 132 seconds (described in reports cited herein) were applied to 51 domestic drilled wells that penetrated bedrock outside major valleys in the part of the Appalachian Plateau of New York drained by the Susquehanna River. Transmissivities calculated from these tests ranged over three orders of magnitude in both the Catskill-Cattaraugus lithofacies (shales, mudstones, siltstones, medium to coarse sandstones, pebbly sandstones) and the Chemung-Hamilton lithofacies (shales, mudstones, siltstones, fine to medium sandstones). Median transmissivity values were 0.000425 foot squared per second (36.7 feet squared per day) in the Catskill-Cattaraugus lithofacies and 0.00055 foot squared per second (47.5 feet squared per day) in the Chemung-Hamilton lithofacies. The distributions of transmissivity values within the two lithofacies were likewise similar. The range and median values of transmissivity were also nearly the same on lower and midlevel hillsides and were only slightly greater on a few upper hillsides. Transmissivities estimated from such easily arranged and analyzed tests may be appropriate for estimating groundwater flux under the small gradients that prevail under natural conditions, but not under larger drawdowns and steeper gradients near clusters of domestic wells. Four of the 51 wells tested were also pumped for 10 to 32 minutes; analysis by the Theis recovery method yielded transmissivities consistent with the brief tests for 2 wells, but 7 to 9 times smaller for 2 wells. Transmissivity values estimated by the PICKINGmodel were not significantly different from values estimated by an automated application of the Picking method (PPC-Recovery) at a probability of 95 percent. Transmissivities calculated by either method from data for time intervals of 120 seconds or less may be of limited practical value because they apply only to a small volume of bedrock close to the pumped well.

New York↗

Estimation of low-flow statistics at ungaged sites on streams in the Lower Hudson River Basin, New York, from data in geographic information systems

A variety of watershed properties available in 2015 from geographic information systems were tested in regression equations to estimate two commonly used statistical indices of the low flow of streams, namely the lowest flows averaged over 7 consecutive days that have a 1 in 10 and a 1 in 2 chance of not being exceeded in any given year (7-day, 10-year and 7-day, 2-year low flows). The equations were based on streamflow measurements in 51 watersheds in the Lower Hudson River Basin of New York during the years 1958–1978, when the number of streamflow measurement sites on unregulated streams was substantially greater than in subsequent years. These low-flow indices are chiefly a function of the area of surficial sand and gravel in the watershed; more precisely, 7-day, 10-year and 7-day, 2-year low flows both increase in proportion to the area of sand and gravel deposited by glacial meltwater, whereas 7-day, 2-year low flows also increase in proportion to the area of postglacial alluvium. Both low-flow statistics are also functions of mean annual runoff (a measure of net water input to the watershed from precipitation) and area of swamps and poorly drained soils in or adjacent to surficial sand and gravel (where groundwater recharge is unlikely and riparian water loss to evapotranspiration is substantial). Small but significant refinements in estimation accuracy resulted from the inclusion of two indices of stream geometry, channel slope and length, in the regression equations. Most of the regression analysis was undertaken with the ordinary least squares method, but four equations were replicated by using weighted least squares to provide a more realistic appraisal of the precision of low-flow estimates. The most accurate estimation equations tested in this study explain nearly 84 and 87 percent of the variation in 7-day, 10-year and 7-day, 2-year low flows, respectively, with standard errors of 0.032 and 0.050 cubic feet per second per square mile. The equations use natural values of streamflow and watershed properties; logarithmic transformations yielded less accurate equations inconsistent with some conceptualized relationships.

New York↗

Hydrogeology of the Susquehanna River valley-fill aquifer system in the Endicott-Vestal area of southwestern Broome County, New York

The village of Endicott, New York, and the adjacent town of Vestal have historically used groundwater from the Susquehanna River valley-fill aquifer system for municipal water supply, but parts of some aquifers in this urban area suffer from legacy contamination from varied sources. Endicott would like to identify sites distant from known contamination where productive aquifers could supply municipal wells with water that would not require intensive treatment. The distribution or geometry of aquifers within the Susquehanna River valley fill in western Endicott and northwestern Vestal are delineated in this report largely on the basis of abundant borehole data that have been compiled in a table of well records. Early in deglaciation, meltwater deposited sand and gravel in channels within or beneath the decaying ice and as narrow terraces along the valley walls. These ice-contact deposits vary widely over short distances from clean (free of silt) and highly permeable to clogged with silt and poorly permeable, but collectively constitute the principal aquifers in Endicott and Vestal. Some ice-contact deposits form a buried ridge, deposited in a meltwater channel within the ice sheet, that approximately underlies the Susquehanna River and (or) its north bank from Endwell westward to Nanticoke Creek and has been tapped by several municipal and industrial wells. Similar but thinner ice-contact deposits discontinuously underlie the valley floor to the south in Vestal, and a smaller buried ridge of ice-contact deposits is likely beneath or west of Nanticoke Creek south of West Corners. As deglaciation continued, a large lake developed; thick deposits of gray silt with red clay layers are continuous north of the Susquehanna River from Endwell to West Endicott, and similar deposits are present discontinuously elsewhere. Late in deglaciation, meltwater deposited highly permeable pebbly sand atop the valley fill, generally atop lacustrine silt. The saturated thickness of this surficial sand is seldom great enough to support large-capacity wells, but where it directly overlies ice-contact deposits it facilitates recharge from precipitation and infiltration of river water to the deeper aquifers. Three localities in Endicott were identified where thick ice-contact deposits capable of supporting municipal supply wells are documented by test wells or extrapolated to be present from nearby data and depositional history. Chemical analyses of water samples disclosed no contaminants in these localities when sampled, but the presence of contaminants or natural high iron a few thousand feet away from each locality is documented.

New York↗

Low flow of streams in the Susquehanna River basin of New York

The principal source of streamflow during periods of low flow in the Susquehanna River basin of New York is the discharge of groundwater from sand-and-gravel deposits. Spatial variation in low flow is mostly a function of differences in three watershed properties: the amount of water that is introduced to the watershed and available for runoff, the extent of surficial sand and gravel relative to till-mantled bedrock, and the extent of wetlands. These three properties were consistently significant in regression equations that were developed to estimate several indices of low flow expressed in cubic feet per second or in cubic feet per second per square mile. The equations explain 90 to 99 percent of the spatial variation in low flow. A few equations indicate that underflow that bypasses streamflow-measurement sites through permeable sand and gravel can significantly decrease low flows. Analytical and numerical groundwater-flow models indicate that spatial extent, hydraulic conductivity and thickness, storage capacity, and topography of stratified sandand- gravel deposits affect low-flow yields from those deposits. Model-simulated discharge of groundwater to streams at low flow reaches a maximum where hydraulic-conductivity values are about 15 feet per day (in valleys 0.5 mile wide) to 60 feet per day (in valleys 1 mile wide). These hydraulic-conductivity values are much larger than those that are considered typical of till and bedrock, but smaller than values reported for productive sand-and-gravel aquifers in some valley reaches in New York. Differences in the properties of till and bedrock and in land-surface slope or relief within the Susquehanna River basin of New York apparently have little effect on low flow. Three regression equations were selected for practical application in estimating 7-day mean low flows in cubic feet per second with 10-year and 2-year recurrence intervals, and 90-percent flow duration, at ungaged sites draining more than 30 square miles; standard errors were 0.88, 1.40, and 1.95 cubic feet per second, respectively. Equations that express low flows in cubic feet per second per square mile were selected for estimating these three indices at ungaged sites draining less than 30 square miles; standard errors were 0.012, 0.018, and 0.022 cubic feet per second per square mile, respectively.

Scientific Investigations Report↗

Recharge to Shale Bedrock at Averill Park, an Upland Hamlet in Eastern New York - An Estimate Based on Pumpage within a Defined Cone of Depression

Water levels beneath parts of Averill Park, a residential hamlet in an upland area of till-mantled shale bedrock in east-central New York, have declined in response to increased withdrawals from new wells. Similar experiences in many upland localities in the northeastern United States have resulted in awareness that the rate of recharge to bedrock can be an important constraint on the density of new development in uplands. Recharge at Averill Park was calculated on the basis of careful estimation of pumpage within a defined cone of depression. The data-collection and recharge-estimation procedures documented herein could be applied in a variety of upland localities in support of community-planning studies. Static water levels measured in 145 wells at Averill Park during the late summer of 2002 defined a 0.54-square-mile cone of depression within which ground-water discharge took place entirely as withdrawals from wells. Rates of withdrawal were estimated largely from surveys in similar neighborhoods a few miles away served by public water supply. Comparison of the water-level measurements in 2002 with measurements on other dates revealed localized declines that could be attributed to new housing developments or commercial demands, but also demonstrated that water levels in 2002 within the cone of depression had stabilized and were not declining persistently over time. Therefore, the current withdrawals were equated to recharge from infiltrating precipitation. Recharge within this area was estimated to average 104 gallons per day per acre, equivalent to 1.4 inches annually, and was sufficient to sustain a residential population of 1.9 persons per acre. This recharge rate is much lower than rates estimated from streamflow records for upland watersheds elsewhere in the northeastern United States. This rate is an average of an unknown larger rate in the 30 percent of the study area where bedrock is discontinuously overlain by less than 30 feet of till and an unknown smaller rate in the remainder of the area where bedrock is overlain by thick till in the form of drumlins. The spatial variation in rate of recharge is inferred from the fact that high heads and strong downward gradients in bedrock, and very hard water with high chloride concentrations caused by winter highway runoff, are largely restricted to the area of discontinuous, thin till. Wells less than 180 feet deep and distant from highways typically yield water of moderate hardness (50-170 milligrams per liter as calcium carbonate) that is caused by dissolution of limestone fragments in the till. Some wells that are more than 180 feet deep yield very soft water (0-50 milligrams per liter) with high pH and high sodium concentrations resulting from ion exchange within the bedrock. Nearly all wells in some areas of thick till yield very soft water. Most wells near the center of Averill Park yield less than 3 gallons per minute. The likelihood of obtaining an additional 2 gallons per minute or more by drilling deeper than 200 feet is calculated to be about 25 percent. Most wells west and southwest of the center yield at least 3 gallons per minute, and the liklihood of obtaining an additional 2 gallons per minute or more by drilling deeper than 200 feet is about 50 percent.

Scientific Investigations Report↗

Analysis of minimally disruptive brief pumping tests of domestic wells completed in bedrock in the Appalachian Plateau of New York

One normal episode of pump operation in domestic wells drilled into bedrock in New York typically lasts about 1 minute and lowers the water level about 1 meter. Measurement of water levels in the pumped well before and during pumping and recovery can be completed in 2 to 3 hours and requires negligible disturbance of the well, so can be easily arranged. Such a test involves less turbulent flow or well loss than longer tests, and can be conveniently analyzed by a new computer program. Tests of 25 wells completed in shale, siltstone, or sandstone in the Appalachian Plateau of New York have been analyzed by this program and by two alternative methods, all of which yield similar transmissivity values and are equally insensitive to storativity.

New York↗

Hydrogeology and water quality of the Clinton Street-Ballpark Aquifer near Johnson City, New York

The Clinton Street-Ballpark aquifer, in the Susquehanna River valley in southern Broome County, N.Y., supplies drinking water to the Village of Johnson City near Binghamton. The hydrogeology and water quality of the aquifer were studied in 1994-95 to identify the source area of 1,1,1-trichloroethane, which was detected at the Johnson City Camden Street wellfield in 1991. The aquifer is generally 100 to 150 ft thick and consists primarily of ice-contact deposits of silty sand and gravel that are overlain by outwash deposits of sand and gravel. These two types of deposits are separated by lacustrine silt and clay of variable thickness into an upper and a lower layer of the aquifer. The coarse deposits form a single aquifer in areas where the lacustrine deposits are absent. Synoptic water-level surveys indicated that ground water moves from upgradient areas flanking the aquifer boundaries toward two major pumping centers?the Anitec wellfield in Binghamton and the Camden Street wellfield in Johnson City. Areas contributing recharge to municipal and industrial wells in the aquifer were delineated by a previously developed groundwater- flow model. The residence time of ground water within the area contributing recharge to Johnson City well no. 2 in the Camden Street wellfield was estimated to be less than 6 years. 1,1,1-Trichloroethane, trichloroethene, and their metabolites were detected in ground water at several locations in and near Johnson City. Relatively high concentrations of 1,1,1-trichloroethane were found in ground water about 3,000 ft north of the Camden Street wellfield. The suspected source is an area bordered on the south by Field Street, on the north by Harry L. Drive, on the east by New York State Route 201, and on the west by Marie Street. A trichloroethene metabolite, cis-1,2-dichloroethene, appears to be migrating westward from U.S. Air Force Plant 59 toward the Camden Street well-field, 1,000 ft southwest of the plant, although this compound has not been detected in water pumped by municipal wells, possibly because it has become diluted by ground water from other locations within the contributing area to the wells.

Open-File Report↗

Mean annual runoff, precipitation, and evapotranspiration in the glaciated northeastern United States, 1951-80

Two maps, compiled at 1:1 million scale, depict mean annual runoff, precipitation, and evapotranspiration in the part of the United States east of Cleveland, Ohio and north of the southern limit of glaciation. The maps are mutually consistent in that runoff equals precipitation minus evapotranspiration everywhere. The runoff map is based on records of streamflow from 503 watersheds in the United States and southernmost Canada, adjusted to/1951-80 and supplemented by records of precipitation at 483 stations. Precipitation at each station was partitioned into point estimates of runoff and evapotranspiration, which were constrained such that the evapotranspiration estimates varied smoothly across the region and decreased with increasing latitude and altitude, and the runoff estimates were consistent with measured runoff from nearby watersheds. A point estimate of runoff was allowed to equal mean runoff in a nearby watershed, or to be somewhat higher (or lower) if a compensating departure from mean watershed runoff could be inferred in distant parts of the watershed on the basis of altitude or regional trends. Then,precipitation contours were drawn to parallel runoff contours but differ from them by the magnitude of nearby estimates of evapotranspiration. These maps may slightly underrepresent mean precipitation and evapotranspiration in areas of high relief, because most precipitation stations in such areas are in valleys. Map accuracy is evaluated. The maps and text are designed to be printed as 34x53 inch plates; they may not be legible if printed in their entirety at appreciably smaller scales. The Arc/Info coverages from which these maps were prepared are available at the Water Resources National Spatial Data Infrastructure Node : ofr96395_eva , ofr96395_pre , and ofr96395_run (evapotranspiration, precipitation, and runoff). Descriptors: *Annual Runoff, *Areal precipitation, *Runoff, *Evapotranspiration Precipitation, Rainfall, New York, New England, Northeast

Open-File Report↗

Effects of surficial geology, lakes and swamps, and annual water availability on low flows of streams in central New England, and their use in low-flow estimation

Equations developed by multiple-regression analysis of data from 49 drainage basins in Massachusetts, New Hampshire, Rhode Island, Vermont, and southwestern Maine indicate that low flow of streams in this region is largely a function of the amount of water available to the basin and the extent of surficial sand and gravel relative to the extent of till and fine-grained stratified drift. Low flow per square mile from areas of surficial sand and gravel is consistently much greater than that from areas of till and bedrock, but flood plains and alluvial fans seem to contribute less low flow per square mile than do other types of surficial sand and gravel. The areal extent of lakes and swamps also correlates negatively with low flow in multiple-regression equations, presumably because intense evapotranspiration from these localities consumes water that would otherwise become streamflow. The annual minimum 7-day mean low flows that occur during summer and fall at 2-year and 10-year recurrence intervals (7Q2 and 7QIO) were selected as indices of low flow and were adjusted to a common base period, 1942-71. Central New England was divided into a region of high relief that com- prises much of New Hampshire, Vermont, and western Massachusetts, and a region of low relief that generally lies to the east and south but also includes the Lake Champlain lowland of Vermont. In the high-relief region, mean basin elevation proved to be the most significant index of the amount of water available. In the low-relief region, mean annual runoff per square mile was more significant than elevation, particularly when multiplied by the areal extent of sand and gravel and that of till. Dividing the areal extent of sand and gravel by stream length improved the fit of regression equations for the low-relief region. Regression equations were developed that explained at least 95 percent of the variation in 7QIO within both the high-relief and the low-relief data sets. Equations proposed for practical application were reasonably consistent with the statistical assumptions of least-squares analysis and yielded 7Q2 and 7QIO values with standard errors of 1.9 and 1.4 cubic feet per second, respectively, for the high-relief region and 2.2 and 1.6 cubic feet per second for the low-relief region. When error was expressed as a percentage of each observed value, median errors were about 25 percent for 7Q2 in both regions, and about 25 and 55 percent for 7QIO in the high-and low-relief regions, respectively. The equations do not apply to basin segments that are substantially affected by urbanization, stream regulation, or ground-water withdrawals, and may not be appropriate where basin characteristics fall outside their range in the data set or where the geologic and topographic maps needed for measurement of basin characteristics are unavailable, or are of small scale or mutually inconsistent.

Connecticut, Maine, Massachusetts, New Hampshire, ↗

Aquifer model of the Susquehanna River valley in southwestern Broome County, New York

A finite-difference model of ground-water flow within stratified drift in the 14-mile reach of the Susquehanna River valley from Binghamton west to the Tioga County line (including Johnson City, Endicott, and Vestal) has been developed. Outwash is the most permeable and extensive type of stratified drift in the valley but has only small saturated thickness except where it is downwarped beneath ice-block depressions. The outwash is commonly underlain by extensive beds of silt and clay deposited in proglacial lakes. Older ice-contact deposits are also extensive and provide the largest yields to wells but are highly variable in thickness and commonly siltier than the outwash. The ice-contact deposits seem to occur mainly as ridges that parallel the axis of major valleys and are buried beneath later lacustrine and outwash sediments. The model simulates horizontal flow in two layers; the upper layer generally represents outwash, and the lower layer generally represents older ice-contact deposits. The model also simulates vertical flow between those layers through the beds of silt and clay or, where the two aquifer layers are in direct contact, through sand and gravel. The model has been calibrated to reproduce observed water levels that represent steady-state conditions. Aquifer properties, recharge from several sources, river stage, and pumpage from several municipal and industrial well fields were calculated from data collected largely in 1981. Major streams were treated as constant specified heads in the upper layer. Data are available to refine the calibration.

New York↗

Ground water in Dale Valley, New York

Dale Valley is a broad valley segment, enlarged by glacial erosion, at the headwaters of Little Tonawanda Creek near Warsaw , New York. A thin, shallow alluvial aquifer immediately underlies the valley floor but is little used. A deeper gravel aquifer, buried beneath many feet of lake deposits, is tapped by several industrial wells. A finite-difference digital model treated the deep aquifer as two-dimensional with recharge and discharge through a confining layer. It was calibrated by simulating (1) natural conditions, (2) an 18-day aquifer test, and (3) 91 days of well-field operation. Streamflow records and model simulations suggest that in moderately wet years such as 1974, a demand of 750 gallons per minute could be met by withdrawal from the creek and from the aquifer without excessive drawdown at production wells or existing domestic wells. With reasonable but unverified model adjustments to simulate an unusually dry year, the model predicts that a demand of 600 gallons per minute could be met from the same sources. Water high in chloride has migrated from bedrock into parts of the deep aquifer. Industrial pumpage, faults in the bedrock, and the natural flow system may be responsible. (Woodard-USGS)

Water-Resources Investigations Report↗

Ground-water pollution by nitrogen compounds at Olean, New York; progress report, June 1977

Ground water in an area in Olean, New York contains high concentrations of nitrogen compounds, which are being slowly flushed from the aquifer as the ground water flows toward a nearby well field where it is pumped out. Construction and regular use of a new production well in the area of nitrogen-rich water would temporarily increase the rate of nitrogen removal by causing more rapid flow of water from the silty upper part of the aquifer downward to the more permeable lower part, and by reducing the distance the water must flow through the lower part to the nearest point of withdrawal. After such a well had been in use for several months and the system had adjusted to the new conditions, the rate of further nitrogen removal would depend on the rate at which nitrogen compounds are leached from the soil by infiltrating precipitation. Alternative techniques for speeding the flushing of the aquifer include artificially increasing the amount of infiltration, changing the rates of withdrawal from existing production wells, and pumping shallow low-yield wells in the area of nitrogen-rich water. (Woodard-USGS)

Open-File Report↗

Infiltration from tributary streams in the Susquehanna River basin, New York

As tributary streams in the Susquehanna River basin leave narrow upland valleys and enter larger valleys floored with permeable stratified glacial drift, they lose water by infiltration through streambeds. The infiltration rate is generally slow near the point of entering a larger valley, but farther downstream it is much faster and is approximately constant per unit distance along a given stream. A conservative average value of infiltration rate in the downstream reach is 10 liters per second per 100 meters of channel. Infiltration from these streams is little influenced by stream width, depth, or temperature and seems to be controlled by permeability distribution beyond the streambed in the alluvium or underlying glacial drift rather than by permeability at the streambed. Hydraulic conductivity of earth materials near each of the streams studied was calculated by applying models that describe steady-state saturated flow into isotropic materials with various boundary conditions. Hydraulic conductivities of 4 to 41 meters per day were obtained; 13 meters per day is suggested as a conservative average value for silty gravel alluvium in the Susquehanna River basin.

New York↗

Ground-water hydrology and subsurface migration of radioisotopes at a low-level solid radioactive-waste disposal site, West Valley, New York

Burial trenches for disposal of solid radioactive waste at West Valley, N.Y., are excavated in till that has very low hydraulic conductivity (about 5 x 10 to the minus 8th power centimeters per second). Fractures and root tubes with chemically oxidized and (or) reduced soil in their walls extend to 3 to 4.5 meters below natural land surface. Preliminary simulations of pressure heads with a digital model suggest that hydraulic conductivity is an order of magnitude greater in the fractured till near land surface than at greater depth. Hydraulic gradients are predominantly downward, even beneath small valleys. The upper part of a body of underlying lacustrine silt is unsaturated; in the lower, saturated part, slow lateral flow may occur. In the older trenches, water began to build up in 1971, overflowed briefly in 1975, and was pumped out in 1975-76. Water levels rose abruptly during major rainstorms in mid-1975, indicating rapid infiltration through cracks in the cover material. The new trenches have maintained low, stable water levels, perhaps because of thicker, more compact cover and less waste settlement; pressure heads near these trenches are low, locally approaching zero, perhaps because of slight infiltration and limited near-surface storage. Peak tritium concentrations in test-hole cores (generally 0.00001 to 0.001 microcuries per milliliter) were found within 3 meters of land surface and are attributed to surface contamination. Concentrations declined rapidly with depth within the fractured till; secondary peaks found at about 9 meters in three holes are attributed to lateral migration from trenches. Other radioisotopes were detected only near land surface. Samples from the walls of shallow fractures revealed no accumulation of radioisotopes. (Woodard-USGS)

Open-File Report↗