Depth-dependent sampling to identify short-circuit pathways to public-supply wells in multiple aquifer settings in the United States |
| |
Authors: | Matthew K Landon Bryant C Jurgens Brian G Katz Sandra M Eberts Karen R Burow Christy A Crandall |
| |
Institution: | 1. U.S. Geological Survey, 4165 Spruance Road, Suite 200, San Diego, CA, 92101, USA 2. U.S. Geological Survey, Placer Hall, 6000 J St., Sacramento, CA, 95819, USA 3. U.S. Geological Survey, 2010 Levy Av., Suite 100, Tallahassee, FL, 32310, USA 4. U.S. Geological Survey, 6480 Doubletree Av., Columbus, OH, 43229, USA
|
| |
Abstract: | Depth-dependent water-quality and borehole flow data were used to determine where and how contamination enters public-supply wells (PSWs) at study sites in different principal aquifers of the United States. At each of three study sites, depth-dependent samples and wellbore flow data were collected from multiple depths in selected PSWs under pumping conditions. The chemistry of these depth-dependent samples, along with samples of the surface discharge from the PSWs, was compared to that of adjacent nested monitoring wells. The results of depth-dependent analyses from sites in Modesto (California), York (Nebraska), and Tampa (Florida) are summarized and compared. Although the exact mechanisms for transport of contaminants to the PSWs varied among these hydrogeologic settings, in all three settings the presence of wells or boreholes or natural preferential flow paths allowed water and contaminants to bypass substantial portions of the aquifer and to reach PSWs or depths in the aquifer more quickly than would have occurred in the absence of these short-circuiting flow paths. The chemistry and flow data from multiple depths was essential to developing an understanding of the dominant flow paths of contaminants to PSW in all three settings. This knowledge contributes to developing effective strategies for monitoring and protection. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|