OGW Tech MM 96.02 To: "William M Alley, Chief, OGW, Reston, VA "cc: "File WRD Archive, , Reston, VA " Subject: OGW Tech MM 96.02 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Thu, 08 Feb 1996 13:50:02 -0500 From: "Velvie E Stockdale, Office Automation Assistant, Reston, VA " In Reply Refer To: February 7, 1996 Mail Stop 411 OFFICE OF GROUND WATER TECHNICAL MEMORANDUM NO. 96.02 Subject: GROUND WATER -- Release of Open-File Report 95-424, "Methods of Conducting Air- Pressurized Slug Tests and Computation of Type Curves for Estimating Transmissivity and Storativity" by Earl A. Greene and Allen M. Shapiro The subject report provides a detailed discussion of the equipment and procedures for conducting and analyzing air-pressurized slug tests. In addition, the Fortran code AIRSLUG to generate type curves for estimating transmissivity (T) and storativity (S) from prematurely terminated air-pressurized slug tests is documented. An MS-DOS 3.5" formatted diskette with an ASCII listing and a compiled (.EXE) version of AIRSLUG is provided. The report also presents field examples where prematurely terminated air-pressurized slug tests have been conducted and interpreted. Air-pressurized slug tests provide a means of estimating formation properties without directly contacting the formation water. This may be beneficial at sites having contaminated formation water, where removing a column of water from the well or cleaning the equipment that comes in contact with formation waters may pose a health concern. Prematurely terminated air-pressurized slug tests are a special case of a slug test where the drawdown is terminated prior to reaching an equilibrium water level. Allen Shapiro and Earl Greene (Shapiro, A.M., and Greene, E.A., 1995, Interpretation of prematurely terminated air- pressurized slug tests: Ground Water, v. 33, no. 4, p. 539-546) developed a method of analyzing the recovery of a prematurely terminated air-pressurized slug test to determine the formation properties; a reprint of this paper is included with this memo. Prematurely terminating the air-pressurized slug test can significantly reduce the time needed to conduct the test, especially at low-permeability sites. We recommend that this report be brought to the attention of technical and management personnel concerned with ground-water hydrology. The Hydrologic Analysis Support Section (HASS) is handling the distribution of AIRSLUG within the Water Resources Division. To obtain the program for use on Data General computers, connect to hassrvares.er.usgs.gov/ by anonymous ftp. Then change the current directory to pub/GW. Retrieve files airslug.tar.Z and readme.airslug. If there are problems with installing the programs, contact HASS by electronic mail (wrdapp) or by telephone (Steve Regan 703-648-5896). Additional copies of the report are available from the authors. /s/ William M. Alley Chief, Office of Ground Water Distribution: A, B, PO, and S (memo only) DC (memo and report)