The United States has become a nation of marginal oil and gas wells. Well abandonments have become commonplace, and each decline cycle in the price of oil and gas brings on a new round of well abandonments. Yet, we know that the majority of oil and gas resources in developed areas are still in the reservoirs. The plugging and abandonment (P&A) of oil and gas wells because of economic conditions is a byproduct of our market economy, and is a "fact of life" in our business. Typically, a well is abandoned because it has fallen below its economic limit, an arbitrary production rate depending, in part, on the present price of oil and gas.

Economic forces are not alone in dictating well abandonment. The timely abandonment of wells is prompted by state regulatory agencies, who must rigidly enforce abandonment statutes for environmental and bonding reasons.

The dilemma brought on by P&A is the damage usually done to the well which precludes inexpensive future access to the reservoir. This is mainly because of damage resulting from the salvaging of casing strings in the well at the time of abandonment. Most oil and gas producing states either allow or even require the recovery of casing during well abandonment. While of questionable economic value, this procedure is commonplace and virtually eliminates future reentry into the wellbore.

This paper discusses the rationale and economic considerations inherent in the P&A process. It suggests a means for regulating the abandonment of oil and gas wells without removing casing strings, while satisfying concerns of environmental damage downhole.

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