Well Testing In Alberta — 1990s Style

Abstract

Abstract This paper presents the highlights of a new guide for well pressure and deliverability testing in Alberta. The guide was developed by a joint Industry-ERCB committee to reduce test costs, improve test quality, and clarify testing regulations. New requirements define quality pressure survey methods, and the minimum number of tests that should be run for prudent reservoir management. Relief from testing is provided for advanced depletion, small reserves, low permeability, heavy oil, low productivity, and reduced spacing. In addition, testing costs are reduced by accepting pressures from shut-in wells, acoustic methods, and drill-stem tests, under certain conditions. Operators can choose the type of deliverability test they run: single- vs multi-point. Tests can be scheduled to optimize field operations. The new well testing environment for the 1990s should become less regulated but this requires that the operating industry be committed to quality testing in accordance with the new guide. The industry, the ERCB, and the public stand to gain from this new approach to data gathering. Introduction In 1989, it cost over $250 million dollars to run pressure and deliverability tests for Alberta's oil and gas wells. This cost is expected to increase significantly, throughout the 1990s, as more wells are needed to supply existing and new markets for oil and gas. The time has come to ensure that we get the most from future testing dollars by carefully examining our data needs and test procedures. The Energy Resources Conservation Board (ERCB) has a mandate(1) to provide for the gathering and dissemination of information regarding the energy resources of Alberta. Accordingly, it developed regulations(2), as early as 1961, for the taking and reporting of well tests. The purpose of these regulations is to ensure adequate quality pressure and deliverability data, for use in engineering and economic studies of Alberta's oil and gas pools. Over the years, these regulations were revised a number of times in response to the changing needs of the ERCB, and the operating industry. In 1987, a joint Industry-ERCB technical committee (the committee) was formed to review the ERCB's well testing regulations. The review has resulted in the development of a new guide for well testing(3). A draft of the new guide was distributed to several industry associations: IPAC, CPA, SEPAC, and CIM, for their comments. Their responses suggest that the guide was well received but that further effort is needed to clarify its contents. The ERCB decided to release a first edition of the guide in the second quarter of 1990. This was done to give both the ERCB and the industry an opportunity to work with the revised requirements, and benefit from them without delay. The ERCB has asked the committee for a review of well testing under the new guide in mid-1991. Any problems encountered can be addressed in a second edition of the guide. Assuming no major problems remain, the ERCB will formally adopt the second edition or the guide as part of its regulations.