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The agreements ified that where the Division and dSignal concurred that downhole <br />conditions precluded reac tng the salt cavern, the goal was to pl~to the deepest attainable depth, but <br />' a minimum of 25 feet below the top of bedrock. This objective assured protection of the unconsolidated <br />glacial aquifers that overlie bedrock, and could only be waived in the case of extenuating circumstances <br />if it became apparent that no further progress could be made. <br />Provisions for departures from the 32-hour time frame and/or the minimum plugging depth were <br />included in the agreement and were only invoked when well-specific circumstances or conditions <br />rendered further work towards the objectives futile or unreasonable. The most common situation where <br />departures were granted occurred in severe subsidence areas where wellbores were sheared by horizontal <br />earth movement associated with subsidence so that the portion of the wellbore below the shear zone had <br />been completely displaced and could not be located. <br />Another innovative regulatory approach was use of an on-site State inspector, or environmental <br />monitor, paid for by AlliedSignal. The monitor was present in the field full-time for all 136 well <br />pluggings that took place between 1993 and 1995. The Division and AlliedSignal concur that there were <br />many advantages of an on-site State inspector for this project, including the following: <br />1) The monitor was empowered with on-site decision-making authority on behalf of the <br />Division, saving the company rig and equipment standb}~ costs. <br />2) The monitor provided on-site one-stop-shopping for all Division of Mineral Resources <br />permits required for the project, increasing scheduling flexibility and further reducing <br />equipment downtime charges. <br />3) The monitor was experienced in well plugging techniques and regulatory requirements, <br />+~ and therefore provided technical recommendations to the company on well plugging <br />equipment, procedures, and materials, resulting in significant cost savings without <br />sacrificing environmental protection. <br />4) Pro-active project management involving constant and open communication among <br />Division of Mineral Resources central (Albany) office staff, reeional (Avon) office staff, <br />the on-site inspector, and AlliedSignal resulted in project completion, ahead of schedule <br />and within budget, without invoking formal dispute resolution procedures established in <br />the well plugging agreement. <br />The monitor's continuous presence on ine site teas especially beneficial to the company because <br />no other State well inspector was based within two hours driving time of the brine field. <br />Special plt<obitre pro6lerrrs turd irrnoi~atir~e solutiorrs.-"The task of well plugging in Tully Valle}• is <br />extremel}• complicated. Ever}• tt'ell is different. Unexpected developments are everyday occurrences" <br />(Yarosz, 1994). Yarosz (1994) further sumn•~arized plugging experience in Tully Valley as follows. <br />i\Such of the plugging procedure which has been applied in Tully has involved <br />adaptation of comentienal methods. Common practice has r.et been sufficient to deal <br />With some of the problems which have been encountered. The problems include: a lack <br />of reliable well records, inabilit} to matMain circulation with liquids. the age and resultant <br />14 <br />771 <br />.4 <br />