This CD contains a 125-page comprehensive study of the hydrogeology of Cedar Valley, Utah County, located in north-central Utah. The report includes 72 figures; two plates, one of which is a potentiometric map of the basin-fill, bedrock, and several perched aquifers; and seven appendices of data. Field investigations included groundwater chemistry sampling, regular water-level monitoring, and multiple-well aquifer testing. The field data were incorporated into a 3D digital groundwater flow model using MODFLOW2000. Seventy percent of the recharge to the Cedar Valley aquifer system is from precipitation in the Oquirrh Mountains. Groundwater generally flows from west to east and exits the aquifer system mostly as interbasin flow through bedrock to the northeast and southeast. The groundwater model showed a 39-year (1969-2007) average recharge to the Cedar Valley groundwater system of 25,600 acre-feet per year and discharge of 25,200 acre-feet per year. A significant volume of precipitation recharge (perhaps 4300 acre-feet per year) does not interact with the basin-fill aquifer but travels within bedrock to discharge to adjacent valleys or as bedrock well discharge. 125 pages + 2 plates

This study is an investigation of the feasibility of an aquifer storage and recovery project using the existing water supply infrastructure of the city of Millville, Utah. The project involved injecting water from a public water supply spring into a public water supply well. Geochemical analysis indicates that the major ion chemistry of the spring water is very similar to that of the principal aquifer, however, the spring water would likely cause minor geochemical changes in the groundwater due to oxidation. The study also showed that the injection well had elevated nitrate concentration which is likely due to septic systems in the area. Overall, the pilot tests showed that injection of water for storage would not be detrimental to the principal aquifer, which has significant storage abilities beyond the capacity of Millville’s water system; however elevated nitrate in the aquifer is a problem that should be addressed.

The City of Millville, located in a prime location for aquifer storage and recovery (ASR), is having issues with elevated nitrate in the Glenridge well, a public water supply sourced from the Cache Valley principal aquifer. To alleviate high nitrate, the city performed an initial injection and pumping test using the Glenridge well. Millville injected water from Garr Spring, another public water supply source of which they own water rights, into the Glenridge well for one week at a rate of 500 gallons per minute. They then pumped the well while monitoring geochemistry to determine the effects on the Cache Valley principal aquifer system. The pre-injection nitrate concentration in the Glenridge well was 7.65 mg/l nitrate as nitrogen, and the nitrate concentration after pumping more than 172% of the volume of water injected was 6.52 mg/l nitrate as nitrogen. There is likely some dispersion of the injected spring water via advection in the aquifer.

Radon is a radioactive gas of geologic origin that is an environmental concern because of its link to lung cancer. Radon is derived from the decay of uranium, and can accumulate indoors in sufficient quantities to pose a health hazard to building occupants. Although the influence of non-geologic factors such as construction type, lifestyle, and weather is difficult to measure, geologic factors that influence indoor-radon levels can be quantified to assess the hazard potential. Geologic factors that influence indoor-radon levels have been studied for three areas in northern Utah to indicate where indoor radon may be a hazard and radon-resistant techniques should be considered in new construction. The three areas include the lower Weber River area in Davis and Weber Counties, Tooele Valley in Tooele County, and southeastern Cache Valley in Cache County. These areas all lie in the depositional basin of Pleistocene Lake Bonneville, and display common geologic characteristics which affect their potential for radon hazards. A numerical rating system was used to assess and map the relative radon-hazard potential in the three study areas. A high-hazard potential was typically found along range fronts where uranium concentrations are higher, ground water is deep, and soils are permeable. Although soil-gas and indoor-radon concentrations broadly correlate to mapped hazard potential, the correlation is imperfect because of atmospheric contamination of soil-gas samples, the presence of locally anomalous concentrations of radon which are beyond the resolution of the sampling grid or map scale, and the effects of non-geologic factors which are not considered in this geologic assessment. 56 pages + 1 plate

Existing and impending water shortages argue for improving water quantity and quality management. Groundwater Optimization Handbook: Flow, Contaminant Transport, and Conjunctive Management helps you formulate and solve groundwater optimization problems to ensure sustainable supplies of adequate quality and quantity. It shows you how to more effecti