The benzene levels in well four, behind city hall, have increased in concentration since July. The water from well three, which contains small amounts of benzene, near the city garage on Railroad Street, is being treated and used as part of the city water supply.
The two wells were found to be contaminated in the fall of 1998.
With permission from the Minnesota Pollution Control Agency, water from well four is being discharged into the storm sewer system.
In November, a containment well was drilled by Casey's Convenience Store and put into use to pump contaminated water from the plume area into the sanitary sewe at a rate of 10 gallons per minute. This was a ploy to keep the contaminated water away from the other city wells.
In January, the test results from the containment well showed the benzene levels as high as 2,200 parts per billion. The level has since dropped to 600 parts per billion.
By pumping the contaminated well by Casey's and well four, the city is drawing the contamination away from wells five and six, which are located south of Highway 23 on the eastern edge of Paynesville.
"During my visit in December, I outlined some options for the city," Jim MacArthur, MPCA, said.
The following options were given to the council in December:
1) Continue to use the present wells but treat the water from well three with a striping tower (an aeration system) to help remove the contamination. Cost: about one-half million dollars.
2) Dig two new wells south of wells five and six. Cost: about one-half million dollars.
3) Dig two new wells and construct a new water treatment plant on the west end of Paynesville on the present airport site. Cost: about $1.6 million.
MacArthur said by going west of town, the chances of the water being contaminated by the same plume would be eliminated. "There is an active water supply at the airport site which flows west to east," he stressed.
"New wells south of wells five and six have the potential of being contaminated because of their location to the plume," MacArthur added.
Since that time, three test wells have drilled south of wells five and six. The first well (about 2,000 feet from the present wells) was found to be in the same aquifer and could pump 1,000 gallons a minute. The other two test wells were further south and found to be dry.
MacArthur suggested the council look at other possible well sites "The area south of the present wells is suitable, but is vulnerable to potential contam-ination," he added.
Gail Haglund representing the Minnesota Department of Health, informed the council if they kept their wells on the east edge of town, the monitoring wells dug last summer could be used as a sentinel system, providing early warnings if the contamination started migrating in that direction.
Ron Mergen, city public works director, told the city council that this is not a black and white issue. There is a lot to take into consideration before a decision can be made about the wells.
MacArthur reminded the council that the state petro fund will cover the cost of drilling new wells at the east side of town. If the city decides to drill on the west end of town, and construct a new water treatment facility, the city would be required to pay the difference (about a million dollars). The petro fund covers the least expensive option.
"How much is it worth to you to have safe drinking water?" Dave Niemen, Minnesota Rural Water, said.
"This is a complicated and serious issue. I encourage you to continue with caution. No matter where you decide to drill a well, do a detailed land use inventory, look at all the options until you are comfortable making a decision," Niemen added.
Mayor Jeff Thompson asked the experts from Rural Water, MPCA, and the Minnesota Department of Health attending the meeting how they would rate Paynesville's water supply.
MacArthur replied that since testing started at the treatment plant, no benzene contamination has been found in the treated water. All of the consultants agreed that the water was safe to drink.
Jim Norton, SEH hydrologist engineer, suggested the city do some samplings on the west end of the city to check out all their options.
He also informed the city of another funding source, Drinking Water Revolving Loan Fund. The deadline for the next application period is April 9.
In other business:
•The council approved an airport joint powers agreement with Paynesville Township.
According to the agreement, the two entities would split expenses not covered by federal and state funds 50-50.
"We tried to cover any and all foreseeable problems," Dave Pschong, airport committee member, said. The township will vote on the agreement at their March 22 meeting.