PERMFILE54123

• Permit No: M1999002
• IBM Index Class Name: Permit File
• Doc Date: 6/18/1999
• Doc Name: OBJECTORS EXHIBITS
• Media Type: D
• Archive: No

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~' 1) The safety ~rd of unplugged wells at the surface been completely removed.
2) One hundred sixty-seven potential sites for dumping of liquid waste have been eliminated.
3) Depending on the plugged depth of each well, the potential for aquifer contamination E
caused by mixing of groundwaters in open wellbores has been either greatly reduced or
eliminated at every unsheared well plugged below bedrock. Success in sealing the
displaced portion of sheared wells is uncertain.
4) The possibility of surface water entry to the brine caverns or other soluble formations via
open wellbores has been eliminated, and access to the cavern or other soluble formations
through wellbores from shallow aquifers has been greatly reduced.
For the period of time during which such statistics were tracked (1993-1995), successful plugging
to the top of the salt cavern required an average of 18 hours of progress-yielding work, as described
above. This result demonstrates the adequacy of the 32-hour time frame for defining a reasonable effort
to realize the plugging goal in wells where conditions were such that plugging to the cavern was likely
to be achieved.
SUNLIL4RY e
The various unique aspects of solution mining and its aftermath in Tully Valley combine to tell
an interesting and educational story. Operations in Tully Valley commenced concurrently with the
nineteenth-century salt boom in western New York, and continued for many decades after most of the
early evaporation plants closed down. The high demand for brine to supply Solvay's soda ash plant
motivated the implementation of several inventive but untested techniques to maximize salt recovery.
One of these methods, roof padding, evolved into standard industry practice and is successfully executed
at modem facilities to control cavern size and shape and create stable caverns. Unfortunately, the grand
scale and uncontrolled nature of salt extraction using the roof padding, wild brining, and "simulated
horizontal drilling" techniques In Tully Valley resulted in significant and damaging subsidence, sinkholes,
and groundwater impacts.
Equally interesting and educational is the story of well plugging in Tully Valley. Myriad
challenges were presented by the number, age, and condition of the wells and the effects of subsidence.
Success at meeting the challenges required dedication, imagination and flexibility on the part of the
operator, contractors and regulators. All involved parties agree that the environmental objectives of well
plugging were achieved to the maximum extent practicable.
\~any lessons can be teamed by examining the history of the Tully Valley brine field, from
startup through plugging of the last well. With respect to well construction, timely plugging, and
controlled cavern development, today's solution miners demonstrate mastery of these lessons.
Nevertheless, vigilant attention to all matters related to design and development of stable caverns and
to timely plugging of depleted wells is necessan• on the pan of both industry and regulators to
successfully prevent unforeseen recurrence elsewhere of problems and impacts similar to those seen in
Tully Valley. "
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