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Source-linked reports with geographic coverage including Pennsylvania.

At least 469 records · Page 26Linked to original sources

Surface-water quality in Pequea Creek basin, Pennsylvania, 1977-79

A study of the Pequea Creek basin was conducted by the U.S. Geological Survey, in cooperation with the Susquehanna River Basin Commission and the EPA from February 1977 through March 1979. Pequea Creek drains an intensive agricultural area of 154 sq mi in southeastern Pennsylvania, and enters the Susquehanna River 30 mi north of the Chesapeake Bay. The study included measurement of streamflow and collection of water and bottom material samples from seven sites in the basin during selected base flows and storms. Water samples were collected daily at a site near the mouth of Pequea Creek, and analyzed for suspended sediment, nitrogen and phosphorus species, organic carbon, and pesticides. Some groundwater samples also were collected and analyzed for nitrate. Annual yields measured from the basin during the study period were 1,950 ton/sq mi for suspended sediment, 13.8 ton/sq mi for total nitrogen, and 1.8 ton/sq mi for phosphorus. These yields are five times higher than any previously measured in the Susquehanna River basin. The discharges of all constituents monitored increased with increasing flow, indicated that a large amount of material in the basin is available for transport to streams during storms. The large yields of nitrogen and phosphorus are probably caused by the intensive agriculture in the basin coupled with large applications of fertilizer and manure to farm fields. Chemical analyses of rainfall samples indicate that precipitation was not a significant source of nitrogen and phosphorus. Excluding nitrate, all constituents measured were transported mainly during storms. Nitrate concentrations during base flow were as high as 10 mg/L as N--the Environmental Protection Agency standard for domestic water supplies. Groundwater sampled from farm wells had nitrate concentrations up to 28 mg/L as N. The largest concentrations of herbicides detected in Pequea basin were for 2,4-D, atrazine, and simazine. The maximum concentrations observed during storms were 1.2, 24, and 5.4 micrograms/L, respectively. The insecticides chlordane and DDT had mean concentrations of 0.02 and 0.01 micrograms/L, respectively. Lindane, PCB, and heptachlor slightly exceed maximum limits during storms.

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Hydrogeology and ground-water quality at a land reclamation site, Neshaminy State Park, Pennsylvania

At Neshaminy State park, the most important aquifer is the informally named 'Trenton gravel' of Pleistocene age, which consists of poorly sorted sand and gravel. This is underlain by less permeable crystalline rock that limits the downward movement of water. Up to 5 feet of Holocene (or perhaps Pleistocene) alluvium consisting of clay and silt was deposited above the Trenton gravel, but much of the surficial material is dredge spoil, mostly sand and silt from the Delaware River. Normally, ground water discharges to the Delaware River and Neshaminy Creek. However, because the Trenton gravel is confined by the alluvium and is hydraulically connected to the Delaware River throughout its entire thickness due to channel dredging, hydraulic-head variations in the river are readily transmitted to wells. Thus, flow is toward the Delaware River and Neshaminy Creek at low tide, but the river and and creek recharge the aquifer as the tide rises. In September 1981 and October 1983, infertile dredge spoil from the Delaware River at Neshaminy State Park was mixed with composted sewage sludge and seeded to grasses to produce a soil product that has not adversely affected ground-water quality as of March 1985. Analyses for pH, specific conductance, nutrients, and heavy metals in ground water at the beginning of the study indicate that the chemistry of the ground water in the dredge spoil at the site differs from that in the Trenton gravel. Analyses of ground-water samples collected after the first two sludge applications (120 tons per acre and 450 tons per acre), indicate that no significant change occurred in the chemistry of the samples from the Trenton gravel, whereas organic nitrogen increased temporarily in ground water from the dredge spoil 6 months after the larger of the two sludge applications, but quickly returned to background levels. The lack of chemical change with time in the ground water implies either that little of the more than 100 inches of precipitation that fell from April 1983 through March 1985 reached the water table or, more likely, that a mechanism exists beneath the soil- factory site that retards or prevents the downard migration of contaminants.

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Ground-water levels in the lower Paleozoic and Precambrian crystalline rocks, southeastern Chester County, Pennsylvania, July and August 1986

A water table contour map of the lower Paleozoic and Precambrian crystalline rocks of southeastern Chester County, Pennsylvania was constructed on the basis of water levels measured in 261 wells in July and August 1986, elevations of 11 springs that were flowing in July and August 1986, and water levels measured in 15 wells. Pre-1986 measurements were incorporated on the map to provide control in areas where more-recent data were not available. The area of crystalline rocks underlies Thornbury, Westtown, East Goshen, and West Goshen Townships, parts of East Whiteland and West Whiteland Townships; and West Chester Borough. Water table altitudes under natural conditions range from 544 ft. above National Geodetic Vertical Datum of 1929 (NGVD of 1929) near Immaculata College to 234 ft. above NGVD of 1929 near Cheyney College.

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Effect of urbanization on the water resources of eastern Chester County, Pennsylvania

The effects of human activity on the water resources of a 207-square-mile area of eastern Chester County was evaluated. The most serious consequence of urbanization is the contamination of ground water by volatile organic compounds, which were detected in 39 percent of the 70 wells sampled. As many as nine compounds were found in one water sample, and the concentration of total volatile organic compounds was as high as 17,400 ug/L (micrograms per liter). In the Chester Valley, volatile organic compounds are moving down the hydraulic gradient caused by quarry dewatering. Movement through the quarries reduces concentrations of these compounds and removes most of them. Phenol was detected in 28 percent of 54 wells sampled, with concentrations up to 7 ug/L. Metals, except for iron and manganese, and other trace constituents generally are not a water-quality problem. However, ground water in an area in Chester Valley has been contaminated by concentrations of boron as high as 20,000 ug/L and lithium as high as 13,000 ug/L. The ground water discharges to Valley Creek, where concentrations of boron are as high as 130 ug/L and lithium as high as 800 ug/L. Concentrations of chloride as high as 2,100 mg/L (milligrams per liter) were found in a well at a former highway salt storage site. Wells completed in carbonate rock downgradient from the Pennsylvania Turnpike had chloride concentrations as high as 350 mg/L. The base-neutral organic compounds bis(2-ethylhexyl) phthalate, di-n-butyl phthalate, and 1,2-dichlorobenzene, and the pesticides alachlor, aldrian, diazanon, DDD, DDT, dieldrin, methyl parathion, picloram, and 2,4-D were detected in a few water samples in low concentrations, However, these organic compounds do not present a widespread water-quality problem. Neither acid organic compounds nor polychlorinated napthalenes (PCN) were detected in ground water. The growth of public water and sewer systems has resulted in a significant interbasin transfer of water. Estimates for 1984 range from a net loss of 630 million gallons in the Valley Creek basin to a net gain of 783 million gallons in the Chester Creek basin. The quantity of wastewater discharged from treatment plants generally correlates well with the altitude of the water table and poorly with water use or precipitation, indicating substantial ground-water infiltration. Estimated ground-water infiltration to the West Goshen treatment plant for 1980-84 was 0.8 cubic feet per square mile, or 10 percent of the long-term average flow of Chester Creek. Estimated ground-water infiltration to the Valley Forge sewer system was as high as 4.9 million gallons per day. Dewatering operations at two active quarries in Chester Valley have lowered water levels locally and increased the range of the fluctuation of the local water table. The spread of the cones of depression caused by quarry pumping is limited by geologic and hydrologic controls. Pumping of high-capacity wells in Chester Valley has caused small local cones of depression and may have caused some reaches of Valley Creek or its tributaries to lose water. One of the greatest effects of human activity on the surface-water system has been the accumulation of organic compounds, particularly PCB and pesticides, on stream-bottom material. PCB, DDE, and dieldrin were found in bottom material from all eight streams sampled. Land-use changes in 10 selected subbasins were quantified and related to stream-benthic invertebrate diversity index. from 1970-80, the diversity index increased at all sites. Subbasins that had a greater change in land use had a greater increase in diversity index. The increase may be due to the banning of certain pesticides such as DDT, a decreasing use of pesticides in urbanizing subbasins, or flushing or burial of older pesticide-contaminated sediment.

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Map showing slope movements in the Oak Forest Quadrangle, Greene County, southwestern Pennsylvania

This map is the first example in the eastern United States of a 1:24,000-scale 7.5– minute quadrangle map that identifies areas with slope—stability problems in detail. Such a map enables the user to make a rapid evaluation of the potential for mass movement. Furthermore, detailed slope movement inventory of this type can serve as a framework for statistical analyses of several factors that cause slope failures, such as the effects of bedrock lithology, soil and slope characteristics, and precipitation. Planners, engineers, soil scientists, geologists, and elected officials should find the map useful in the assessment of slope hazards and planning for future land use. Final evaluation of any site within the quadrangle should be based on an examination by a soils engineer or an engineering geologist. Field investigations in the springs of 1981 and 1982 and the fall of 1981 involved nearly 60 days of traverses. The foot traverses were supplemented by the interpretation of the land surface on vertical black-and-white aerial photography flown in January and February of 1973 at a scale of nearly 1:24,000. Earlier aerial photography flown in June and July 1939 at a scale of 1:20,000 and more recent but significantly smaller scale photography (1:80,000) flown in June 1977 supplied additional documentation. More than 1,200 active or recently active and 900 older slope movements were identified. The geologic map of the Oak Forest quadrangle (Roen, 1972) is one of several geologic maps at a scale of 1:24,000 in eastern and central Greene County. Stone (1932) wrote an earlier report of the geology and mineral resources of Greene County. A series of reconnaissance landslide maps at 1:24,000 scale based mainly on aerial photographic interpretation included Greene and adjacent counties (Hackman and Thomas, 1978). Selection of the Oak Forest quadrangle for a more comprehensive study of the slope movements was based on the existence of a recent geologic map (Roen, 1972), sizeable tracts of both forested and non-forested land, nearby precipitation record stations, a large number of pipelines which could offer pertinent data, and good accessibility of terrain from secondary roads. Finally, Hackman and Thomas (1978) showed that the area was representative of any quadrangle in the northern part of the Dunkard basin in its distribution and density of slope movements. The quadrangle is located about 65 km southwest of Pittsburgh, Penn. (fig. 1). Three distinct drainage systems (north, east, and south trending) are represented within the quadrangle (fig. 2).

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Statistical analyses of flood frequency, low-flow frequency, and flow duration of streams in the Philadelphia Area, Pennsylvania

Flood frequency, low-flow frequency, and flow-duration characteristics were computed for 26 stream-gaging stations in and near Philadelphia. Data were obtained from 21 continuous-recording stations and five stations that were initially continuous-recording stations, but which were subsequently converted to crest-stage stations. The annual peak flows were fitted to the three-parameter log-Pearson Type III distribution to develop the flood- frequency characteristics. The range of the reported annual recurrence intervals for flood-frequency depends on record length. Low-flow frequency characteristics for various numbers of consecutive days were also defined by fitting data to the log-Pearson Type III distribution. Standard analyses of daily discharges produced the duration curve characteristics. Results of these analyses are tabulated.

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Results of a preimpoundment water-quality study of Swatara Creek, Pennsylvania

The water quality of Swatara Creek prior to impoundment by the proposed Swatara Creek Reservoir in south-central Pennsylvania was studied from July 1981 through October 1982. The report, done in cooperation with the Pennsylvania Department of Environmental Resources (PaDER), Bureau of State Parks, presents information on existing water-quality conditions. A discussion of possible water-quality conditions in and downstream from the planned impoundment is also included. Precipitation measured near the study area at Lebanon, Pennsylvania from October 1981 through September 1982 was 8 percent below normal. Streamflow for the same period at Swatara Creek at Harper Tavern just downstream from the study area was 15 percent below the average annual flow. Swatara Creek above Highway 895 has been degraded by acid mine drainage. The main inflow to the planned impoundment has 2.1 times the discharge of Lower Little Swatara Creek--a forested and agricultural basin that is also tributary to the proposed impoundment. During the 1982 water year, 17,400 tons of suspended sediment were transported from the study area. About 46 percent of the annual load was transported during 3 days of high flow. Inflows to the planned impoundment from both Lower Little Swatara Creek and Swatara Creek above Highway 895 were poorly buffered. Measured concentrations of alkalinity and acidity were usually less than 10 mg/L (milligrams per liter) and 5 mg/L as CaCO3, respectively. The inflows contain high concentrations of nutrients and metals that would probably stratify in a reservoir. Maximum concentrations of dissolved nitrate and total phosphorus were 2.6 mg/L and 0.31 mg/L, respectively. At Lower Little Swatara Creek; these concentrations are well above those needed for growth of algae. Maximum observed concentrations for total recoverable iron, aluminum, and manganese at Swatara Creek above Highway 895 at Pine Grove were 100,000 ug/L (micrograms per liter), 66,000 ug/L, and 2,300 ug/L, respectively. Large increases in metal concentrations along with simultaneous decreases in pH and increases in acidity confirm that mine drainage continues to degrade the water quality of Swatara Creek and may have a large impact on water quality of the planned impoundment. Iron, lead, copper, and zinc concentrations periodically exceeded the U.S. Environmental Protection Agency (U.S. EPA) criteria for freshwater aquatic life. Concentrations of manganese and lead also exceeded the U.S. EPA criteria for domestic water supplies and human health, respectively. The water quality of the Swatara Creek Reservoir will depend on characteristics such as (1) the detention time of water in the lake, (2) the timing and extent of thermal and chemical stratification, (3) sedimentation, and (4) the chemical loading and concentrations in the lake. Each of these characteristics may depend in part, on streamflow. The impoundment will act as a sediment trap and thus reduce the concentrations of total phosphorus, iron, aluminum, lead, copper, and zinc immediately downstream from the impoundment. Large storm discharges and releases from the hypolimnion of the reservoir to attain the winter-pool level may contain low oxygen concentrations and elevated concentrations of iron, aluminum, lead, copper, and zinc. Unless conservation releases from the multi-level release gates are carefully controlled, low dissolved-oxygen levels and high metal concentrations may degrade the downstream water quality and be detrimental to the aquatic community.

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Occurrence of nitrate and herbicides in ground water in the upper Conestoga River basin, Pennsylvania : water-quality study of the Conestoga River headwaters, Pennsylvania

Nitrate-nitrogen and herbicide ground-water data is being collected by the u.s. Geological Survey as part of the nationwide Rural Clean Water Program designed to determine the effects of agricultural-management practices on water quality. Data collected from September 1982 to October 1983 · in the 188-square mile intensively farmed upper Conestoga River basin indicates high nitrate and detectable herbicide concentrations in ground water are closely associated with agricultural practices and carbonate geology. Maximum nitrate-nitrogen concentrations from 42 wells and one spring ranged from 37 to 40 milligrams per liter in the agricultural areas, and 12 to 19 milligrams per liter in the nonagricultural areas. Median concentrations of nitrate generally were three times higher in wells that penetrated carbonate rock than in wells that penetrated noncarbonate rocks. More than 40 percent of the wells in the carbonate and agricultural areas had dissolved-nitrate concentrations that exceeded 10 milligrams per liter as nitrogen, the criterion established by the U.S. Environmental Protection Agency as excessive for drinking water. Atrazine, simazine, alachlor, and metolachlor were found almost exclusively in the agricultural and carbonate areas. Water-quality data collected before and after installation of terraces, manure storage, and nutrient and herbicide management practices is valuable in determining the effectiveness of these agricultural practices, and will provide useful information to protect agricultural land, local water supplies, the Conestoga and Susquehanna Rivers and ultimately the Chesapeake Bay.

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Metal contamination in wildlife living near two zinc smelters

Wildlife in an oak forest on Blue Mountain was studied 10 km upwind (Bake Oven Knob site) and 2 km downwind (Palmerton site) of two zinc smelters in eastern Pennsylvania, USA. Previous studies at sites near these smelters had shown changes in populations of soil microflora, lichens, green plants and litter-inhabiting arthropods. The 02 soil litter horizon at Palmerton was heavily contaminated with Pb (2700 mg kg −1 ), Zn (24 000 mg kg −1 ), and Cd (710 mg kg −1 ), and to a lesser extent with Cu (440 mg kg −1 ). Various kinds of invertebrates (earthworms, slugs and millipedes) that feed on soil litter or soil organic matter were rare at, or absent from, the Palmerton site. Those collected at Bake Oven Knob tended to have much higher concentrations of metals than did other invertebrates. Frogs, toads and salamanders were very rare at, or absent from, the Palmerton site, but were present at Bake Oven Knob and at other sites on Blue Mountain farther from the smelters. Metal concentrations (dry wt) in different organisms from Palmerton were compared. Concentrations of Pb were highest in shrews (110 mg kg −1 ), followed by songbirds (56 mg kg −1 ), leaves (21 mg kg −1 ), mice (17 mg kg −1 ), carrion insects (14 mg kg −1 ), berries (4·0 mg kg −1 ), moths (4·3 mg kg −1 ) and fungi (3·7 mg kg −1 ). Concentrations of Cd, in contrast, were highest in carrion insects (25 mg kg −1 ), followed by fungi (9·8 mg kg −1 ), leaves (8·1 mg kg −1 ), shrews (7·3 mg kg −1 ), moths (4·9 mg kg −1 ), mice (2·6 mg kg −1 ), songbirds (2·5 mg kg −1 ) and berries (1·2 mg kg −1 ). Concentrations of Zn and Cu tended to be highest in the same organisms that had the highest concentrations of Cd. Only a small proportion of the metals in the soil became incorporated into plant foliage, and much of the metal contamination detected in the biota probably came from aerial deposition. The mice from both sites seemed to be healthy. Shrews had higher concentrations of metals than did mice, and one shrew showed evidence of Pb poisoning; its red blood cell ALAD activity was greatly reduced, one kidney contained acid-fast intranuclear inclusion bodies, and the other kidney had 280 mg kg −1 Pb (wet wt). The livers from two cuckoos from Palmerton had elevated Pb concentrations (18 and 25 mg kg −1 , wet wt). Most of the songbirds seemed to be healthy.

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Trap efficiency of a sediment-control pond below a block-cut coal mine in Fayette County, Pennsylvania

The U. S. Geological Survey determined the efficiency of a pond constructed to control sediment from a surface coal mine site by measuring runoff and sediment loads at the inlet to and discharge from the pond during storms. The pond is below a 17.9-acre block-cut coal mine in Fayette County, Pennsylvania and has a permanent pool capacity of 60,000 cu ft. The capacity at the principal spillway and the emergency spillway are 128,900 and 175,500 cu ft, respectively. The pond is equipped with a 3-inch flow control valve, used by the mine operator to regulate the pond stage between the permanent pool and the principal spillway. Data were collected during five moderate storms when the 3-inch control valve was intentionally opened. The ration between the quantity of water in the pond at the start of the storm and the quantity to runoff to the pond was calculated for each storm. The ratios were 3.6, 2.5, 8.6, 2.9, and 1.5 for the five storms. The measured trap efficiencies were 98.1, 92.8, 99.6, 99.1, and 98.2%, for the five storms. (USGS)

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