Portions of an existing active treatment system were utilized and new components were installed to convert the Sanborn treatment system from active to passive in late 2004.  These improvements lowered annual treatment costs from over $31,000 to less than $10,000 (~2/3 decrease in annual treatment costs).  The capital improvements designed by BMI cost about $85,000 to construct with a payback period of about 4 years.  Cost estimates and approach used to establish trust fund were provided by BMI.  The pebble quicklime system and related settling ponds were left in place to accommodate future maintenance, as needed.  To date, other than routine inspections and monitoring, there has been essentially no maintenance performed on the system which is now over 12 years of continuous operation.  Acidic metal-laden mine drainage has been successfully treated to meet permit compliance requirements since installation.

 Harbison-Walker Refractories Company
SMP #4475SM10
Woodward Township, Clearfield Co., PA
Bruce Hamilton, Environmental Engineer
(bhamiliton@thinkhwi.com; 412-375-6820)
2004 Completion Date