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Lawrence A. Eccles

Publications and source records attributed to Lawrence A. Eccles.

8 recordsLinked to original sources

Dissolved organic carbon (DOC), an index of organic contamination in ground water near Barstow, California

The alluvial aquifer underlying and adjacent to the Mojave River near Barstow, California, has been subjected to degradation from percolation of industrial and municipal wastes for more than 60 years. Effluents discharged to the aquifer have contained high concentrations of both organic (detergents, oil and grease, phenols, humic compounds, and others) and inorganic (chromium, chloride, phosphates, and others) substances. The concentration of dissolved organic carbon (DOC), as determined by a wet combustion technique, has been shown to be a definitive parameter in identifying ground water affected by waste disposal. DOC concentrations ranged from 0.1 to 0.8 milligram per liter in the nondegraded ground water and exceeded 6 milligrams per liter in the ground water affected by the waste discharge. The general distribution of DOC in the degraded ground water has been defined both areally and vertically. The vertical distribution of DOC and other constituents indicates that two plumes of degraded water occur at different depths. A comparison of the areal distribution of DOC and detergents (as MBAS) suggests that some organic compounds may have been adsorbed by the aquifer sediments.

California↗

Ground-water quality along the Mojave River near Barstow, California, 1974-79

The quality of ground water in the alluvium along the usually dry Mojave River near Barstow, Calif., has been monitored since 1974. Degradation has occurred as a result of wastewater discharge and irrigation return. Characteristics of the degraded ground water include concentrations of dissolved solids exceeding 1,000 milligrams per liter, odor threshold numbers exceeding 5, dissolved organic carbon exceeding 2.0 milligrams per liter, chloride exceeding 250 milligrams per liter, phenols exceeding 1 microgram per liter, and methylene blue active substances exceeding 0.20 milligram per liter. Large flows in the river during the winters of 1977-78 and 1978-79 recharged the aquifer with water from storm runoff. The ground-water-quality monitoring data showed that few changes in the concentration and distribution of chemical constituents occurred between 1974 and 1977, but between 1977 and 1979 there were overall decreases in most constituents and in odor. The monitoring data also showed that between 1977 and 1979 the degraded ground water spread and moved downgradient, whereas prior to 1977 it had been generally confined to an area between Barstow and the U.S. Marine Corps Supply Center. (USGS)

Water-Resources Investigations Report↗

Ground-water quality in the upper Santa Ana River basin, southern California

The principal ground-water quality problems in the Santa Ana River basin, as determined from two samplings (1968-69 and 1977-78), are high concentrations of dissolved solids in general and nitrate-nitrogen in particular. The distribution of dissolved solids exceeding 800 milligrams per liter was smaller in area in 1977-78 than in 1968-69. Distribution of nitrate-nitrogen exceeding 10 milligrams per liter was larger in area in 1977-78 than in 1968-69. Concentrations of dissolved solids and nitrate-nitrogen decreased with depth. The network of wells used in the 1977-78 sampling program provides only a general appraisal of overall quality for most of the upper Santa Ana River basin. It is not adequate for detailed appraisals of specific problem areas because it lacks sufficient areal coverage and construction information for the wells sampled. (Kosco-USGS)

California↗

Pesticide residues in agricultural drains, southeastern desert area, California

A study is being made to determine the occurrence and distribution of pesticides in the agricultural drains for approximately 3/4 million irrigated acres in the southeastern desert area of California. This report describes the results of the first year of sampling and analyzing (1) water in the drains , (2) bed material in the drains, (3) water from field tile-drainage lines, and (4) irrigation tailwater and water in the drains directly exposed to drift from aerial application of pesticides. Residues of almost all the pesticides selected for monitoring were found in water in the drains. Examination of the data to determine the probable source of pesticides indicated generally slight concentrations from bed material in the drains, usually no detectable concentrations from field tile-drainage lines, and apparently large concentrations from irrigation tailwater and drift from aerial application. (Woodard-USGS)

Water-Resources Investigations Report↗

Distribution of dissolved nitrate and fluoride in ground water, Highland-East Highlands, San Bernardino County, California

In the Highland-East Highlands area of southern California, concentrations of nitrate in water from many wells exceed the U.S. Environmental Protection Agency 's and the California Department of Health 's recommended limit for public water supplies. The nitrate standards for public water supplies in the study area are commonly met by blending the high-nitrate water with low-nitrate water before distribution; however, some of the low-nitrate water sources have fluoride concentrations that exceed the optimum level, or in a few cases exceed the maximum level recommended by the California Department of Health. Nitrate-nitrogen concentrations in the study area are generally between 1 and 20 milligrams per liter. In general, nitrate-nitrogen concentrations exceeding 10 milligrams per liter are found in water from wells perforated at depths of less than 500 feet. (Woodard-USGS)

California↗

Distribution of nitrate in ground water, Redlands, California

Wells producing water with nitrate as nitrogen concentrations in excess of 10 milligrams per liter are common throughout the Redlands, Calif., area. Nitrite as nitrogen concentrations in water from the saturated part of the aquifer ranged from much greater than 20 milligrams per liter at the water table to less than 5 milligrams per liter at depths of 300 feet below the water table. This depth dependence suggests that the major source of nitrate is a generalized area-wide infiltration of high-nitrate water downward from the surface through the unsaturated zone. The nitrate concentration in water from individual wells is dependent primarily upon depth and well construction--particularly aquifer seal and aquifer penetration--and secondarily upon well location. Nitrate concentrations of water in wells are increased by heavy pumping which causes high-nitrate water near the water table to be pulled deeper. (Woodard-USGS)

Water-Resources Investigations Report↗

Sources of arsenic in streams tributary to Lake Crowley, California

Lake Crowley is the largest single source of water for the city of Los Angeles. More than 50 percent of the water entering the Los Angeles-Owens River aqueduct flows through Lake Crowley. Arsenic enters Lake Crowley primarily from hot springs in Long Valley. Sixty percent of the arsenic discharged to Lake Crowley is from hot springs in Hot Creek Gorge. The hot-spring water containing about 1,000 micrograms per litre of arsenic blends with the water flowing in the creek and is usually diluted to a concentration of about 200 micrograms per litre; additional dilution occurs downstream. About 75 percent of the arsenic in Hot Creek is discharged from only two springs. The remaining sources of arsenic in the gorge are poorly defined seepage and flow from numerous small springs. Other sources of arsenic in Long Valley are from either high volume and low-arsenic concentration springs, such as the springs at Hot Creek Fish Hatchery, or high-concentration and low-volume springs, such as those found in the vicinity of the Alkali lakes. These other sources individually are small in comparison with the source in Hot Creek Gorge. It seems unlikely that arsenic from these sources could cause the arsenic concentration in Lake Crowley to exceed the Environmental Protection Agency's recommended criterion (limit) for a public water supply.

California↗

Occurrence of dissolved organic carbon in selected ground-water samples in the United States

A study of nonvolatile DOC (dissolved organic carbon) in ground water was conducted to establish base levels of naturally occurring dissolved organic materials. Samples of ground water were obtained at 100 sites in 27 States. Samples were pressure filtered at the time of collection and immediately frozen on dry ice. DOC concentrations were determined by wet oxidation of organic carbon to carbon dioxide which was measured by an infrared analyzer. The DOC concentrations ranged from less than the 0.1 mg/l limit of detection to 15 mg/l. Concentrations of DOC were directly correlated with specific conductance and alkalinity, but did not correlate with pH. The DOC mean concentration was 1.2 mg/l; however, the DOC median value was lower at 0.7 mg/l. Differences in DOC concentration for various types of consolidated rock aquifers were slight; for example, median DOC values for sandstone, limestone, and crystalline rock aquifer types ranged from 0.5 to 0.7 mg/l. No difference was found in the median DOC concentration between shallow (<200 ft; 61 m) and deep (>200 ft) sand and gravel aquifers.

Journal of Research of the U.S. Geological Survey↗