Geology topics

James G. Setmire

Publications and source records attributed to James G. Setmire.

4 recordsLinked to original sources

USGS1988

Trace elements and pesticides in Salton Sea area, California

Concentrations of numerous potentially toxic trace elements and pesticides were determined in water, sediment, and biota from the Salton Sea area in southestern California. Comparison of results with data from other studies in this area and from other areas, and with various water-quality standards or criteria, indicate that selenium probably is the principal contaminant of concern in the Salton Sea basin and that it probably is related to agricultural practices. Selenium is mobilized in the subsurface drainwater produced by agricultural irrigation and transported in ditches and rivers, some of which pass through or near the Salton Sea National Wildlife Refuge before entering the Salton Sea. Some selenium apparently is incorporated into the food chain. In response to the finding of elevated selenium residues in fish from the area by State agencies, the Imperial County Health Department has issued a health advisory restricting or prohibiting human consumption of fish from the Salton Sea and drains.

Conference Paper↗

USGS1984

Water quality in the New River from Calexico to the Salton Sea, Imperial County, California

The New River enters the United States at Calexico, Calif., after it crosses the international boundary. Water-quality data from routine collection indicated that the New River was degraded by high organic and bacterial content. Intensive sampling for chemical and physical constituents and properties of the river was done May 9-13, 1977, to quantify the chemical composition of the water and to identify water-quality problems. Concentrations of total organic carbon in the New River at Calexico ranged from 80 to 161 milligrams per liter and dissolved organic carbon ranged from 34 to 42 milligrams per liter; the maximum chemical oxygen demand was 510 milligrams per liter. Intensive sampling for chemical and biological characteristics was done in the New River from May 1977 to June 1978 to determine the occurrence of the organic material and its effects on downstream water quality. Dissolved-oxygen concentration was measured along longitudinal profiles of the river from Calexico to the Salton Sea. A dissolved-oxygen sag downstream from the Calexico gage varied seasonally. The sag extended farther downstream and had lower concentrations of dissolved oxygen during the summer months than during the winter months. The sag of zero dissolved-oxygen concentration extended 26 miles in July 1977. In December 1976, the sag extended 20 miles but the minimum dissolved-oxygen concentration was 2.5 milligrams per liter. The greatest diel (24-hour) variation in dissolved-oxygen concentration occurred in the reach from the Calexico gage to Lyons Crossing, 8.8 miles downstream. High concentrations of organic material were detected as far as Highway 80, 19.5 miles downstream from the international boundary. Biological samples analyzed for benthic invertebrates showed that water at the Calexico and Lyons Crossing sites, nearest the international boundary, was of such poor quality that very few bottom-dwelling organisms could survive. Although the water was of poor quality at Keystone Road, 36 miles downstream, it was able to support a benthic community. The April sample had more than 9,150 organisms on a multiplate sampler, 8,770 of which were of one species. Farther downstream at the Westmorland gage, the water quality, as indicated by the number and diversity of organisms, had improved over that at the Keystone site. The Alamo River at its outlet to the Salton Sea--the control site--had the greatest diversity of all the study sites. This diversity, when compared with the diversity at the Westmorland gage, indicated that the effects of the degraded water quality observed at the New River at Calexico are detected as far as 62 miles downstream. Standard bacteria indicator tests indicate that fecal contamination exists in the New River. Counts of fecal coliform bacteria ranged from 180,000 to 2,800,000 colonies per 100 milliliters for the 20-mile reach from Calexico to Highway 80, and fecal streptococcal bacteria ranged from 5,000 to 240,000 colonies per 100 milliliters.

California↗

USGS1980

Quality of urban runoff, Tecolote Creek drainage area, San Diego County, California

The quality of storm runoff from a 9.2-square-mile urbanized watershed, Tecolote Creek, San Diego County, Calif., was studied during nine storms from September 1976 through May 1977. Specific conductance reached 2,100 micromhos and total residue concentrations reached 2,770 milligrams per liter. The chemical oxygen demand concentration in 95% of the samples exceeded 50 milligrams per liter, a concentration that may be sufficient to cause severe oxygen depletion in areas of the receiving water, Mission Bay. Lead concentrations in all samples exceeded concentrations thought to affect some aquatic organisms. Median total nitrogen and total orthophosphorus concentrations were far in excess of concentrations known to cause nuisance growth of algae in lakes. Fecal coliform bacteria concentrations greatly exceeded recommended levels for primary contact recreation water. Concentrations of pesticides--heptachlor, malathion, chlordane, DDT, diazinon, and dieldrin--frequently exceeded the recommended maximums for marine or freshwater aquatic systems. Total loads of selected constituents are calculated and may be used to estimate the impact of runoff on the receiving water. (USGS)

Water-Resources Investigations Report↗

USGS1979

Water-quality conditions in the New River, Imperial County, California

The New River, when entering the United States at Calexico, Calif., often contains materials which have the appearance of industrial and domestic wastes. Passage of some of these materials is recognized by a sudden increase in turbidity over background levels and the presence of white particulate matter. Water samples taken during these events are usually extremely high in organic content. During a 4-day reconnaissance of water quality in May 1977, white-to-brown extremely turbid water crossed the border on three occasions. On one of these occasions , the water was intensively sampled. The total organic-carbon concentration ranged from 80 to 161 milligrams per liter (mg/l); dissolved organic carbon ranged from 34 to 42 mg/l, and the chemical oxygen demand was as high as 510 mg/l. River profiles showed a dissolved-oxygen sag, with the length of the zone of depressed dissolved-oxygen concentrations varying seasonally. During the summer months, dissolved-oxygen concentrations in the river were lower and the zone of depressed dissolved-oxygen concentrations was longer. The largest increases in dissolved-oxygen concentration from reaeration occurred at the three drop structures and the rock weir near Seeley. The effects of oxygen demanding materials crossing the border extended as far as Highway 80, 19.5 miles downstream from the international boundary at Calexico. Fish kills and anaerobic conditions were also detected as far as Highway 80. Standard bacteria indicator tests for fecal contamination showed a very high health-hazard potential near the border. (Woodard-USGS)

California↗