Publications

An ethanesulfonic acid metabolite of metolachlor (metolachlor ESA) was identified in soil-sample extracts by negative-ion, fast-atom bombardment mass spectrometry (FAB-MS) and FAB tandem mass spectrometry (FAB-MS/MS). Production fragments from MS/MS analysis of the deprotonated molecular ion of metolachlor ESA in the soil extract can be reconciled with the structure of the synthesized standard. Th

The geochemical transport of cyanazine and its metabolite cyanazine amide (CAM) was compared to atrazine and its metabolite deethylatrazine (DEA) at three sites in the Mississippi River basin during 1992 and six sites during 1993. The floods of 1993 caused an uninterrupted exponential decline in herbicide concentrations; whereas, in 1992 herbicide concentrations varied mostly in response to two di

Pesticide concentrations in ground water at Rocky Mountain Arsenal (RMA) near Denver, Colorado, were determined using solid-phase extraction (SPE) gas chromatography/mass spectrometry (GC/MS) procedures and enzyme-linked immunosorbent assay (ELISA) for cyclodiene insecticides and triazine herbicides. Matrix interferences resulted in inconclusive results for some GC/MS analyses due to baseline dist

A commercially available enzyme-linked immunosorbent assay (ELISA) plate kit for screening of cyclodiene insecticides (aldrin, chlordane, dieldrin, endosulfan, endrin, and heptachlor) was evaluated for sensitivity, cross reactivity, and overall performance using ground-water samples from a contaminated site. Ground-water contaminants included several pesticide compounds and their manufacturing by-

This volume contains 50 articles describing severe, widespread, or unusual flooding in 28 of the 50 States during 1990 and 1991. Each flood is described to an extent commensurate with its significance and the availability of data on the hydrology and the damages. Each article includes one or more maps showing the general area of flooding. Most articles include tables of data that allow comparison

A digital ground-water flow model was developed to simulate steady-state and transient effects of municipal well pumping from an alluvial aquifer on streamflow in the Republican River near Junction City, Kansas. Seepage survey results indicated that streamflow loss in the vicinity of the municipal well field ranged from 1 to 5 ft3/s (cubic feet per second). Simulations of May 1993 conditions indic

Water samples were collected from 175 wells in 12 Midcontinental States (Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, Wisconsin) from 1992 through 1994 to determine the spatial distribution of nutrients, pesticides, and volatile organic compounds in ground water, and to document the potential effects of the historic flooding that occur

A study of the distribution and transport of atrazine in surface water in the 1,117 square-mile Delaware River Basin in northeast Kansas was conducted from July 1992 through September 1995. The purpose of this report is to present information to assess the present (1992-95) conditions and possible future changes in the distribution and magnitude of atrazine concentrations, loads, and yields spati

During spring and summer 1993, record flooding inundated much of the upper Mississippi River Basin. The magnitude of the damages-in terms of property, disrupted business, and personal trauma was unmatched by any other flood disaster in United States history. Property damage alone is expected to exceed $10 billion. Damaged highways and submerged roads disrupted overland transportation throughout th

Median monthly atrazine concentrations detected in surface-water samples from the Big Blue River basin (1977-86) exceeded the U.S. Environmental Protection Agency health-advisory level (3.0 micrograms per liter) during May through September. Herbicide loads transported from the basin in 1986, expressed in tons and in percentage of amount applied, were alachlor (1.2 tons, 0.23 percent), atrazine (1

Median suspended-sediment concentrations ranged from 100 to 110 milligrams per liter for 3 stations on the Kansas River and from 4 to 110 milligrams per liter for 10 stations on tributary streams during May 1987 through April 1990. For tributary stream stations upstream from large reservoirs, concen- trations in the 90th percentile ranged from 240 to 3,200 milligrams per liter. The larger median a

Available surface water-quality data were used to provide an initial assessment of current water-quality conditions for 1978-86, define long-term trends in constituent concentrations, and relate current water-quality conditions and trends to human and natural factors in the lower Kansas River basin, Kansas and Nebraska. This basin drains 15,300 square miles of predominantly agricultural land and i