Richard N. Downer

Re: Technical Meeting, November 7, 2001, with EPA and their consultants.

New to the discussions were Phil Leonhardt and Don Reynolds representing Shepard Miller Consulting Environmental and Geotechnical Engineers and Scientists of Fort Collins, Colorado; Robert Seal, II and Jane Hamsham representing the U.S. Geological Survey in Reston, Virginia and Robert Hedin representing Hedin Environmental of Pittsburgh, Pennsylvania.

In addition the following were present: Mike Young, Bill Lovely, Frank Bergstrom, Scott Foster, Scot Acone, Jeremy Picard, Richard Downer, Cindy Cook and Sherwood Reed.

The discussions were a free wheeling "round-table" amongst engineers and scientists. No new technical information came out. I reminded all present that the cover thickness (translated "truck traffic") continued to be a major community concerns. The EE/CA will continue to hold all options for thickness and material types open.

A brief discussion ensued about the exact nature of diversion ditches. Phil Leonhardt described the practice used on several western mine sites. The ECE/CA as written covers all options for ditches, both as described by Phil and imagined by myself.

Don Reynolds mentioned the Hardpan cover and distributed two journal papers which discussed the technique. As I understood his remarks, only laboratory experiments have been carried out to date. He admitted that pilot studies on Elizabeth Mine tailings would be necessary. He did not have longevity data. Nor, did he have actual data on the self-healing aspects of the Hardpan cover. I think the option will be left in the EE/CA, but I did not get the impression that there were any strong advocates around the table.

The discussions kept wandering back to the impact of TP-3 on the cost of the cleanup and Cindy Cook kept reminding us that the Historic Preservation Process was still being played out between ANR and the SHPO.

Overall, I expect few technical changes to the EE/CA as currently written. The EE/CA’s intent is to include all possible options for later study during the design phase. I am not aware of any new capping technologies or stability reinforcement techniques that have not been mentioned in the EE/CA. I believe the EE/CA is currently flexible enough to cover all future envisioned water diversion ditches, capping techniques and stability reinforcement options.

Woody Reed has already commented on the ALD’s and SAP’s.

Richard N. Downer, P.E

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