| Abstract: | Drawdown and recovery data from two aquifer tests in central Nassau County, NY were used to calculate aquifer characteristics by several methods to aid in predicting the response of the aquifer system to stress. The first test, on May 12, 1978, entailed pumping the Magothy aquifer for 12 hours; the second on July 30-31, 1985, entailed pumping the upper glacial aquifer for 24 hours. Drawdown and recovery data from both tests were analyzed through analytical solutions and curve-matching procedures, and the resulting hydraulic values were used as initial values in a finite-element radial-flow numerical model to simulate the observed drawdowns and recoveries. Storativity values obtained by all methods were consistent with published estimates; but hydraulic conductivity values were higher than published estimates. The simple analytical solutions and curve-matching procedures gave reasonable values of most terms quickly, but the greatest confidence is in the estimates made with the finite-element model. These estimates for the Magothy aquifer were: horizontal hydraulic conductivity of 100 ft/d; ratio of horizontal to vertical conductivity, 5; and specific storage, 0.0001. Estimates for the upper glacial aquifer were: horizontal hydraulic conductivity, 380 ft/d; ratio of horizontal to vertical hydraulic conductivity, 2.5; and specific yield, 0.15. (USGS) |
| Genre: | USGS Numbered Series |
| ProdID: | 29211 |
| Citation Author: | Prince, K. R.; Schneider, B. J. |
| Citation Contributing Office: | |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | - |
| Citation Editor: | |
| Citation End Page: | |
| Citation Issue: | |
| Citation Keywords: | |
| Citation Language: | ENGLISH |
| Citation Larger Work Title: | |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | vi, 43 p. :ill. ;28 cm. |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | U.S. Geological Survey ;
Books and Open-File Reports Section [distributor], |
| Citation Series: | Water-Resources Investigations Report |
| Citation Series Code: | WRI |
| Citation Series Number: | 87-4211 |
| Citation Search Results Text: | Estimation of hydraulic characteristics of the upper glacial and Magothy aquifers at East Meadow, New York, by use of aquifer tests; 1989; WRI; 87-4211; Prince, K. R.; Schneider, B. J. |
| Citation Start Page: | |
| Citation Volume: | |
| Citation Year: | 1989 |
| Type: | citation/reference |
| Text: | Estimation of hydraulic characteristics of the upper glacial and Magothy aquifers at East Meadow, New York, by use of aquifer tests; 1989; WRI; 87-4211; Prince, K. R.; Schneider, B. J. |
| URL (THUMBNAIL): | http://pubs.usgs.gov/wri/1987/4211/report-thumb.jpg |
| URL (DOCUMENT): | http://pubs.usgs.gov/wri/1987/4211/report.pdf |
| Date Other: | Sat, 1 Jan 1994 00:00 -0600 |
| Publisher: | U.S. Geological Survey ;
Books and Open-File Reports Section [distributor], |
