Droamz   C. La Follet
  Acdrney Goneal

  Gerald 5 W~lcox



23 West Wminbo Avenue                                        De"yAdony
GO
NO" Addee P.O. Box 7357
ldloon, WISC 5ln 53707-757

    Mr. Howard S. Drucke $iller, Director
    Bureau of Environmental Analysis & Review
    Department of Natural Resources
    P.O. Box 7921
    Madison, WI 53707

         Re: DEIS Comments

    Dear Mr. Druckenmiller:

         The following are additional DEIS comments for the record
    based on comments made orally at the hearing and on comments
    filed by other participants in the DEIS public comment period.

                      Contaminant Transport Modeling

--aN     As an alternative to the modeling presented in the DEIS, the
(39DNR should re-run the model with conservative assumptions for
    each parameter.   The present modeling really represents a "best
    case" contaminant transport picture since seven (7) of the nine
    (9) variables chosen in the modeling are the least conservative
variables.      In addition, contingency measures should be proposed
(328)for ground water contamination from the project site, especially
  -the MWDF.

                                   MWDF

         The design of the facility depends on neutralizing the acid
    generation potential of the tailings by the addition of lime. No
 recalculation is included on how much lime or water treatment
 (329)sludge would be necessary to prevent acid formation. What is the
 \..Zvolume of lime, either added lime or as part of the water
     treatment sludges, would be necessary to assure the ph would
     remain above 4?



-l



    Mr. Howard S. Druckenmiller
    July 3, 1986
    Page 2



    plan to insure that acid conditions are not generated in the
    tailings other than by monitoring of the leachate? By the time
    the leachate is monitored, significant acid formation could
    already have taken place.

         What possibility is there of piping in the bentonite-amended
O soil liners under the MWDF, reclaim ponds, and other project
    facilities?  Piping failures are common problems which can lead
    to ground water contamination.

         If, for some reason such as less than expected mine inflow,
t the water treatment plant does not produce the expected volume of
3  sludges  with  neutralizing  capacity,  will   the  applicant  be
    required  to  provide   additional  lime?    How  will   the  acid
31conditions in the tailings mass be monitored during operations?
   H _Ias any calculation been done to estimate whether the expected
   sludge volume would neutralize the tailings? How much lime would
be required and would this amount of lime change the sizing
V_ requirements of the ponds?

         The public should be informed that if the ph drops in the
    tailings mass, the waste and leachate would be incompatible with
Othe bentonite-amended soil liner.      Furthermore, acid conditions
   would result in the classification of the waste as hazardous.
   Since the design does not meet federal requirements for hazardous
   waste containment, the generation of acid in the tailings could
   render the design ineffective to prevent leachate from reaching
   the ground water, especially during operations.

         The DEIS does a very poor job of explaining the concept of
(directing precipitation to the tailings pond perimeters so it
bwill infiltrate the outer edge of the tailings mass. What is the
    purpose of this infiltration since standard design practices call
    for directing water away from the facility after closure? What
,-is the potential impact on embankment stability of having this
(i7)water directed into the embankments? This represents a change
\.-from the applicant's original closure water handling plan.    What
    is the reason for the change?

         Since the MWDF can will have to remain an effective barrier



mLon wLis not occur*JIn.   1   Lne  n glue p% uu
bbitbecllxu could become established which would
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WailruA. Arb
AsaatNtAlony Oewal
(605) 2665
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JUL  7 1986



July 3, 1986



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