New Abandonment Technology New Materials and Placement Techniques

Abstract

Abstract Recent industry concerns related to the increasing number of idle wells in the United States prompted a search by Chevron Environmental Management Company (EMC) for more reliable and cost effective means of well abandonment technology. This paper presents the results of the search, laboratory research and field pilot testing conducted by EMC and the California Department of Conservation Division of Oil Gas and Geothermal Resources. Additionally, the cost analysis and future areas of research are addressed. The successful implementation of the abandonment techniques discussed in this paper show substantial savings on a per well basis while providing a reduction in future liability. Introduction The maturation of the oil and gas industry in the United States has resulted in a large number of idle and orphaned wells (IOGCC). At the 1999 SPE Environment Forum in Breckenridge, Colorado, the number one environmental, health and safety issue was the ever-increasing number of wells waiting to be abandoned, the increasing number of orphan wells and the lack of funding to significantly reduce the liabilities. Chevron Environmental Management Company (EMC), in an effort to address idle and poorly abandoned wells, formed a task force with the following objectives:Improve abandonment methodology, andReduce the cost by at least 30%. The EMC Task Force, located in the Bakersfield, California office of Chevron North American Producing Division, consisted of a wide variety of engineers, scientists, business specialists and regulators. The team was challenged with the task of abandoning 1700 wells in less than two years. The team was divided into two major divisions, the 1700 well team charged with well identification, methodology streamlining and implementation and the research team, charged with technology advancement. Research Team Methodology The research team began with an extensive regulatory review focused on California requirements, as well as broader government and accepted industry practices. The issues associated with current technologies were then identified. New technologies were reviewed and the most promising technology was then investigated through literature review, laboratory research and a field pilot study. Industry and Regulatory Standards American Petroleum Institute's Well Abandonment Guidance The American Petroleum Institute (API) has prepared a report entitled, "Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations". This document is accepted as the oil and gas industry's standard for executing environmentally sound abandonments, focusing on protection of freshwater aquifers from fluid migration and isolation of hydrocarbon production and water injection intervals. It is often cited by regulatory agencies as one of the key resources used in regulatory development. Two means in which wells can play a role in contamination are identified in the guidance document:The well becomes a conduit for fluid migration from the producing zone, freshwater aquifers and the surface; orSurface water seeps into the wellbore and migrates into an aquifer. Both opportunities for contamination can and have been minimized, in part, through the utilization of prudent completion and abandonment safeguards.