An analysis of private potable water well data was conducted for seven single family residential developments in southern Chester County, Pennsylvania. Background data were available for 165 wells within the communities when the wells were first drilled in the 1980s and early 1990s. Sampling of 75 wells within these same communities was performed in 2006 to determine whether conversion of the land to residential housing along with the use of conventional on-lot septic systems had resulted in elevated concentration of nitrate-nitrogen in the drinking water aquifer. The data indicate that prior land use influenced the occurrence of nitrate-nitrogen in the drinking water aquifer. The median nitrate-nitrogen concentration for the 165 wells in the background dataset was 2.9 mg/L. One hundred-seven of those wells were drilled on land previously used for active agricultural purposes. The median nitrate concentration in these wells was 3.8 mg/L. Of 48 wells drilled on forested land, the median nitrate concentration was 1.1 mg/L, approximately 3.5 times lower than those drilled on active agricultural land. The median nitrate concentration in the 2006 sampling dataset was 3.6 mg/L, an increase of 0.7 mg/L. The data indicate that conversion of the land has not resulted in contamination of the drinking water aquifer with respect to nitrate-nitrogen. Likewise, the data suggest that the conversion has not resulted in significant improvements to overall water quality.

Geologic and geochemical investigations and a survey of mines and prospects indicate that those parts of the Chuckwalla Mountains Wilderness Study Area (chiefly in the Red Cloud Canyon and Corn Springs Wash vicinities) that are intruded by propylitically altered mafic dikes with spatially associated quartz veins and shear zones have moderate or high potential for the presence of undiscovered low-to medium-grade gold, silver, and tungsten resources in vein deposits. High stream-sediment concentrations of molybdenum strongly suggest that parts of those areas intruded by the dikes also contain molybdenum-bearing minerals and thus have moderate or high potential for the presence of undiscovered molybdenum resources. However, there has been no recorded production of molybdenum in the region and any resources that may be present in the study area are likely to be significant only if the mineralized quartz veins and shear zones are manifestations of an extensive subsurface quartz-vein stockwork system. All areas with moderate or high potential for gold, silver, tungsten, or molybdenum resources also have low potential for the presence of undiscovered copper and lead resources. Low potential for the presence of undiscovered tin and thorium resources exists in the north part of the wilderness study area. Sand, gravel, and stone suitable for construction materials are found in the study area, but similar or better quality materials are abundant and accessible outside the area. No new mineral occurrence was located during this study.

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