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Well SO~f 22-H-1 <br />• Procedure: <br />Four slug tests were run on well SODf 22 H-1 on September 3, 1982. Test <br />#1 was a falling head test using a 5.5 feet by 2.36 inch diameter slug. Test <br />p2 consists of recovery data after removal of the 5.5 foot slug. Since responses <br />were very fast in this well, the test was repeated using a larger slug. Test <br />... #3 is falling head response after inserting a 14.3 feet by 2.36 inch diameter <br />slug. Test #4 is the recovery of the well after removing the 14.3 foot slug. <br />Interpretation: <br />Early test data from all 4 slug tests are plotted together on one graph <br />using the Cooper et. al. type curve method (Figure IV-7). As seen in this data <br />plot, the points within the first 2 minutes of the tests represent over 95% <br />(H/Ho=0.05) of the wells response to the slug. Data from test #1 provide the <br />best fit with the type curve. The first 3 minutes of data from test #4 are <br />atypical, showing almost no response, then a sudden drop to nearly total re- <br />~:: • covery at t=3.67 min. Transmissivity is calculated primarily from test #1 data <br />at T=2283 gpd/ft. <br />Later test data are plotted using the line source method (Ferris $ Knowles). <br />Each test is plotted separately and transmissivity is calculated from the late <br />test data which fall on a straight line which passes through the origin of the <br />graph. Although earl}• test data were somewhat erratic, transmissivities cal- <br />culated from all four tests by the line source method are very consistent. The <br />average of four tests is T(ave)-776 gpd/ft. with a range from T(#2)=716 gpd/ft. <br />to T(#1)=859 gpd/ft. <br />Because of the differences in the two methods of calculating T, the line <br />source method usually estimates a lower value than the type curve method which <br />accounts for well storage. The difference seems to be approximately a factor <br />C::: <br />of 2 or 2.5. Examples of this are evident in data for wells SOM 1-H and SOM <br />C 76 A in which there are excellent matches of the data to both methods. Be- <br />cause well storage is important in determining transmissivity from a single well <br />a test, the value of T determined from the Cooper et. al. method is considered <br />zs ESA Geotechnical Consultants <br />