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heavy metal issue, they felt it was a mute point; however, he has not yet receJveg the information on water quality. Therefore, he is not prepared to make a recommendation on the matter. Mr, Otter - gave a brief overview of the project which is scheduled to be operational Dy July, 1991; and that timetable is crucial. The system proposed is the best technology available today to treat Volatile Organic Compounds (VOCs) in the groundwater and meets ali quality standards by the federal and state governments. He went on to explain that the wter will De 95 percent treated at the time It Is being put into the City's storm sewer. The City wl]] 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 available technology available, and that is what they are going. Steve Kol]od~e. Engineer 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 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 this process, the amount would De so diluted that the MPCA is not concerned. Mr. Jankowsk] - didn't know what background level could be used for heavy metals other than the drinking water standards. There are many environmental concernsl however, the MPCA is responsible for seeing that what WMMt Goes will De adequate and proper. Mr. Otter - explained how the air stripping system works, noting that no heavy metals wi]] be removed in the process. Also, mercury has not been a proD]em in the landfill, though they wi]] 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 around the landfill. They have been carefully monitoring the grounc~water ]eve]sl and that wi]] be continually monitored, the anticipation being that there wi]] be about a one foot draw-gown on Sunfish Lake after about 1 1/2 years. They wI]] be able to aetermine the effect of the project after each month of operation. However, they anticipate there should De no wide spread d~aw-down or dryln~ up of private we]is in the area because the cone of depression from this operation w]]] only be what one might expect from an agricultural well. Mr, Otter - thought it may be possible 'that. the technology will change in ¢lve to ten yea~s: however, they have oes]gned the system CITY COUNCIL/DECEMBER ii, i990 Page 12 of 17