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heavy metal issue, they felt it was a mute point; however, he has not yet recelved the information on water quality. Therefore, he Is not prepared to make a recommendation on the matter. Mr, Otter - gave a brief overvlew of the project which is scheOuled to be operational by July, 1991; and that timetable is crucial. The system propose~ is the best technology available today to treat Volatile Organic Compounds (VOCs) in the groundwater and meets all quality standards by the federal and state governments. He went on to exp]aln that the wter will be 95 percent treated at the time it ls being put into the Clty's storm sewer. The Clty will not be a party to the NPDES permit and will not be obligated to do any monitoring or recording because of that permit, as that has been verbally agreed to by the PCA. They have done water quality testing on the Mississippi River on several occasions and found no VOCs, but that can vary depending on the types and times of discharges into the river. Their requirements are to meet the Federal standards using the best aval]ab]e technology available, and that is what they are ~oing. Steve Ko])od~e. Enolneer for WMMI - reviewed some technical aspects of the project, that basically the PCA Is looking at "no net effect to the river". They are doing what they have been told to do, and that Is to use the best available technology to remove VOCs to the 95 percent removal standard. Mr. Hart]ey also explained that the ground water has naturally occurring heavy metals that discharge Into the river. If some are discharged to the river through thls process, the amount would be so diluted that the MPCA is not concerned. Mr. J~Dkowck.i - didn't know what background level cou]d be used for heavy metals other than the drinking water standards. There are many environmental concerns; however, the MPCA is responsib]e for seeing that what WMMI does will be adequate and proper. Mr. Otter - explained how the air stripping system works, noting that no heavy metals will be removed in the process. Also, mercury has not been a problem in the landfill, though they will continue to monitor and submit the results to the City, county, and MPCA. He then responded to a question on draw-down on the aquifers aroun~ the landfill. They have been carefully monitoring the Groundwater ]eve]s; an~ that wl]] be continually monitored, the anticipation being that there will be about a one foot draw-down on Sunfish Lake after about 1 1/2 years. They will be able to determine the effect of the project after each month of operation. However, they antlclpate there should be no wlde spread draw-down or drying up of private wells in the area because the cone of depression from this operation wi]] only be what one might expect from an agricultural well. Mr. Otter - thought it may be possible that the technology wi]] change in five to ten years; however, they have designed the system CITY COUNCIL/DECEMBER ii, 1990 Page 12 of 17