Surface seals have been used as the primary method for underground coal fire abatement in the western United States. The effectiveness of a surface seal can take years to determine. By the time there is evidence that a surface seal has failed, the integrity of the seal may be lost. The U.S. Bureau of Mines funded investigators who utilized probes to monitor underground temperatures at 13 surface seal coal fire abatement projects completed in Montana. Nine of the projects were completed in the 1950's, and the Bureau had recorded temperature readings in test holes when construction was completed. The four other projects were constructed in the 1980's. Temperatures were monitored before construction, during construction, and after construction for periods ranging from 1 to 5 years. Possible correlations between fire activity as determined by temperature measurements and variables before, during, and after construction were determined. Monitoring temperatures through boreholes using permanently placed probes appears to be an effective means of determining the condition of an underground coal fire. The correlation drawn may aid in determining early, relatively inexpensive, remedial actions for surface seals when the temperature readings indicate fire activity has not been controlled. Also, to illustrate the considerations involved when specifying soil seal parameters, a cost-effectiveness study was performed for a hypothetical site.