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Research about Saunders County, Nebraska

Source-linked reports with geographic coverage including Saunders County, Nebraska.

2 recordsLinked to original sources

Tapwater-contaminant mixtures and risk in a biofuel-facility impacted private-well community

We assessed private-well drinking water (DW) at the point of use ( i.e. , tapwater, TW) within a rural Nebraska community around a state-closed biofuel facility, which used pesticide-treated corn seed as feedstock for ethanol production. Organic (485), inorganic (34), and microbial (13) analytes were assessed at 15 locations in June 2022, to evaluate the relative contribution of facility-consistent pesticides (seed-treatment fungicides and insecticides) to overall TW-contaminant exposures and predicted human-health risks. Thirty-three organics (12 pesticides) and 28 inorganics were detected, the former including the fungicide sedaxane, insecticide chlorantraniliprole, and multiple neonicotinoid insecticides/degradates, all consistent with seed treatment and respective biofuel-facility waste. Assessment of pesticides only at extant point-of-use (POU) treatment taps at three sites demonstrated complete elimination of all TW-pesticide detections. Based on detection of maximum pesticide concentrations in a home located downstream along a creek capturing facility runoff, pesticides only were assessed in January 2023 again at this home and at three adjacent locations, confirming results at the former and documenting decreasing TW-pesticide concentrations, including neonicotinoids, with increasing distance from the creek. Human-health DW benchmarks are not available for many detected pesticides, including the detected fungicide and insecticides, but precautionary screening levels were exceeded frequently due to multiple inorganics. The results indicate that exposures to multiple (median: 4.5; range: 1–7) co-occurring TW contaminants of potential human-health concern are common, warranting consideration of point-of-entry or POU treatment(s) throughout the community to reduce or eliminate unrecognized exposures to TW contaminants, including facility-associated pesticides in down-gradient locations. More broadly, results emphasize the importance of continued characterization of private-TW exposures, employing a environmentally informative analytical scope, to identify and mitigate risks of unrecognized exposures in private-well-dependent rural communities.

Nebraska

Availability of water in eastern Saunders County, Nebraska

The sand and gravel deposits of Quaternary age constitute the most important ground-water reservoir and are the source of nearly all the water pumped from wells in the area. An estimated 3.5 million acre-feet for good quality water is stored in these deposits and an additional 1.5 million acre-feet is stored in the underlying Dakota Sandstone. Even larger quantities are stored at greater depths in the Paleozoic dolomites and sandstones, but the water is of poorer quality. Pumpage for irrigation since 1956 is estimated to have ranged from about 2,500 acre-feet (1962) to about 6,000 acre-feet (1957). The town of Wahoo annually pumps about 460 acre-feet, and other towns pump an estimated total of 180 acre-feet. In 1963 the City of Lincoln pumped 27,000 acre-feet from its well field alongside the Platte River in the southeast corner of the area; since then pumpage has increased and probably is likely to continue to do so. Pumping at Lincoln city well field induces recharge from Platte River. The quantity of ground water pumped to date is very small compared to the amount of water stored in the rocks. Furthermore, most of the ground water withdrawn has been replaced by infiltrating precipitation and by influent seepage from the Platte River. The large quantity of ground water in storage in addition to the flow of the Platte River indicates that the water resources of the area, if managed properly, can be developed much more extensively without appreciably depleting the supply.

Nebraska