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K.C. Bastian

Publications and source records attributed to K.C. Bastian.

4 recordsLinked to original sources

Detection of persistent organic pollutants in the Mississippi Delta using semipermeable membrane devices

From semipermeable membrane devices (SPMDs) placed in five Mississippi Delta streams in 1996 and 1997, the persistent organic pollutants (POPs) aldrin, chlordane, DCPA, DDT, dieldrin, endrin, heptachlor, mirex, nonachlor, and toxaphene were detected. In addition, the insecticides chlorpyriphos, endosulfan, and hexachlorocyclohexanes were detected. Two low-solubility herbicides not detected commonly in surface water, pendimethalin and trifluralin, were also detected.

Science of Total Environment↗

Occurrence of cotton herbicides and insecticides in playa lakes of the High Plains of West Texas

During the summer of 1997, water samples were collected and analyzed for pesticides from 32 playa lakes of the High Plains that receive drainage from both cotton and corn agriculture in West Texas. The major cotton herbicides detected in the water samples were diuron, fluometuron, metolachlor, norflurazon, and prometryn. Atrazine and propazine, corn and sorghum herbicides, were also routinely detected in samples from the playa lakes. Furthermore, the metabolites of all the herbicides studied were found in the playa lake samples. In some cases, the concentration of metabolites was equal to or exceeded the concentration of the parent compound. The types of metabolites detected suggested that the parent compounds had been transported to and had undergone degradation in the playa lakes. The types of metabolites and the ratio of metabolites to parent compounds may be useful in indicating the time that the herbicides were transported to the playa lakes. The median concentration of total herbicides was 7.2 μg/l, with the largest total concentrations exceeding 30 μg/l. Organophosphate insecticides were detected in only one water sample. Further work will improve the understanding of the fate of these compounds in the playa lake area.

Science of Total Environment↗

Surface water-ground water interaction: Herbicide transport into municipal collector wells

During spring runoff events, herbicides in the Platte River are transported through an alluvial aquifer into collector wells located on an island in the river in 6 to 7 d. During two spring runoff events in 1995 and 1996, atrazine [2-chloro-4-ethylamino-6-isopropylamino- s -triazine] concentrations in water from these wells reached approximately 7 µg/L, 70 times more than the background concentration in ground water. Concentrations of herbicides and metabolites in the collector wells generally were one-half to one-fifth the concentrations of herbicides in the river for atrazine, alachlor [2-chloro-2′-6′-diethyl- N -(methoxymethyl)-acetanilide], alachlor ethane-sulfonic acid (ESA) [2-((2,6-diethylphenyl) (methoxymethyl)amino)-2-oxoethane-sulfonic acid], metolachlor [2-chloro- N -(2-ethyl-6-methylphenyl)- N -(2-methoxy-1-methylethyl)acetamide], cyanazine [2-((4-chloro-6-(ethylamino)-1,3,5 triazin-2-yl)-amino)-2-methylpropionitrile], and acetochlor [2-chloro- N -(ethoxymethyl)- N -(2-ethyl-6methyl-phenyl) acetamide], suggesting that 20 to 50% river water could be present in the water from the collector wells, assuming no degradation. The effect of the river on the quality of water from the collector wells can be reduced through selective management of horizontal laterals of the collector wells. The quality of the water from the collector wells is dependent on the (i) selection of the collector well used, (ii) number and selection of laterals used, (iii) chemical characteristics of the contaminant, and (iv) relative mixing of the Platte River and a major upstream tributary.

Journal of Environmental Quality↗

Microtox(TM) characterization of foundry sand residuals

Although foundry residuals, consisting mostly of waste Sands, represent a potentially attractive, high-volume resource for beneficial reuse applications (e.g. highway embankment construction), prospective end users are understandably concerned about unforeseen liabilities stemming from the use of these residuals. This paper, therefore, focuses on the innovative use of a microbial bioassay as a means of developing a characterization of environmental suitability extending beyond the analytical coverage already provided by mandated chemical-specific tests (i.e., TCLP, etc.). Microtox(TM) bioassays were conducted on leachates derived from residuals obtained at a wide range of facilities, including: 11 gray and ductile iron foundries plus one each steel and aluminum foundries. In addition, virgin sand samples were used to establish a relative 'natural' benchmark against which the waste foundry sands could then be compared in terms of their apparent quality. These bioassay tests were able to effectively 'fingerprint' those residuals whose bioassay behavior was comparable to that of virgin materials. In fact, the majority of gray and ductile iron foundry residuals tested during this reported study elicited Microtox(TM) response levels which fell within or below the virgin sand response range, consequently providing another quantifiable layer of Support for this industry's claim that their sands are 'cleaner than dirt.' However, negative Microtox(TM) responses beyond that of the virgin sands were observed with a number of foundry samples (i.e. four of the 11 gray or ductile iron sands plus both non-iron sands). Therefore, the latter results would suggest that these latter residuals be excluded from beneficial reuse for the immediate future, at least until the cause and nature of this negative response has been further identified.

Waste Management↗