A study of the Bruce Village water wells reflects a bio-film is present and is the cause of a manganese build up in the village’s water.
During the Jan. 4 Bruce village meeting, Larry Gotham of presented a 12-page report to the trustees of a recent test of the village’s water wells conducted by Water Quality Investigations.
A sample collected on Nov. 10 contained a manganese concentration of 1,100 per liter in Well #3. A sample collected on Nov. 25 resulted in the same contamination level. The village trustees were notified on Dec. 7 of these levels and issued a warning following the notification.
Well # 1 in the Village of Bruce tested 500 and 540 on each of the days samples were collected for Well #3.
According to the notice, water in the village of Bruce contains manganese exceeding the U.S. Environmental Protection Agency’s health advisory level of 300 micrograms per liter. Manganese levels in well water vary throughout Wisconsin and are typically below 50 micrograms per liter.
According to Wisconsin Department of Health Services, manganese levels over 300 µg/L pose an immediate health risk for sensitive groups. When manganese levels are above 300 µg/L, people over the age of 50 and infants less than 6 months old should stop using the water for drinking and preparing foods and beverages that use a lot of water. Manganese at these levels also poses a long-term health risk for everyone.
During a Dec. 15 special meeting, Bruce Village trustees voted to take Well 3 offline. Doing this, brings the manganese level to 500 to 520, where Well 1 tested in November.
Bruce Fire Chief Jim Locke said his concerns with turning Well #3 off are the icy road in the winter and the timeframe for turning the well back online in the event of a fire. Alone, Well #1 is not strong enough to meet the needs of a large structure fire. Having Well #3 off during the summer is less critical, according to Locke.
In the event of a structure fire, Well #3 will be turned online to help maintain water levels for the fire. If Well 3 is brought back online, the Village will be required to post notices for seven days to not drink the water. After seven days, manganese levels should return to that of Well #1.
Locke requested to allow two or three people to have keys and training to turn Well #3 on and off in the event of a fire. Darlene Wundrow, Village Employee, is currently the only person with this access and it would be important in the event of a fire to ensure quick action can be taken.
In 1991, the village experienced the same problem with the water.
Well 3 was built in the early 1980’s and at that time tested 40 microns of manganese.
According to a 12-page report of results from Water Quality Investigations, the nutrient conditions in the aquifers for both wells are causing a thick and unstable biofilm formation in the wells. The biofilm is in the borehole and gravel pack regions of both wells, and while it is naturally occurring, it is likely causing microbial induced corrosion of the steel casing and minerals in the aquifers.
This corrosion is causing manganese to be added to the water pumped from the wells.
“This biofilm develops slowly over time to cause microbial induced corrosion of aquifer minerals and of the steel well casing and pump column, which adds manganese and metals to water pumped from the wells,” according to the report.
The biofilm is causing a nitrification in the well and is causing a biological process that converts ammonia or proteins to nitrate. The nitrate reacts as an acid which is causing a corrosion of metal surfaces and is partially responsible for corrosion in the wells and aquifer minerals, according to the report.
Data in the report indicate that the “nitrifying biofilms need copper, zinc and iron to support their metabolism, which promotes biofilm to cause corrosion of these minerals if not in the water.”
Results of the test indicate that controlling the presence of the biofilm in Well #3 will reduce nitrate and manganese concentrations in water pumped from the well. “Data also suggest a correlation between biofilm in the wells and lead and copper corrosion in the Village’s premise plumbing system,” according to the report.
Gotham told village trustees during the January meeting that five steps will need to be taken to correct the situation.
First, the a plan to rehabilitate both wells will need to be developed. The plan will need to include who to chlorinate, clean, rehabilitate the wells, as well as measuring the volume of water and how long water is left in the well. The wells will need a thorough cleaning.
Second, the developed plan will need to be submitted to the Department of Natural Resources for approval. The DNR will have 90 days to review the plan, but the village, according to Gotham, may have to submit a time extension to allow time for the plan to be approved.
Once approved, the village will need to hire a well driller to rehabilitate the wells. At this time the cost to rehabilitate the wells is unknown. In 1991 the cost to rehabilitate one well was approximately $20,000 however other corrective work was done at that time.
Village trustees and Gotham are anticipating completing a similar process, however it will be more in depth and a long term maintenance will be kept up with to avoid this problem in the future.
Each of the two wells will be rehabilitated separately.
The fourth step will be to develop a plan to correct the problem of copper and lead concentrations in the water. A unidirectional flushing of the water distribution system will help control the copper corrosion, according to the report.
The final step is to develop a long range plan to maintain the wells. One possible example that could be done to maintain the wells is to chlorinate the wells every one to two years.
According to the DNR manganese is a naturally-occurring and essential element in small amounts for healthy bones, for the body to produce glucose, proper development and to heal wounds.
“Manganese may be in your water if it has a rust color, causes staining of faucets, sinks or laundry, or if it has an off taste or odor. Wisconsin has set a groundwater quality enforcement standard for manganese of 300 micrograms per liter (µg/L),” according to the DNR.
Exposure to high levels of manganese can affect the nervous system, reproduction systems and can impact proper function in the kidneys.
People over the age of 50 and infants less then six months old are the most sensitive to these effects. In older adults, high levels of manganese may cause a disorder similar to Parkinson’s disease. In infants, exposure to high levels of manganese may affect brain development and impact learning and behavior, according to the DNR.
In other news, trustees approved the purchase of a portion of a property for $10,000 as part of the North Main Street reconstruction project. The purchase will be for the Coleman Street lift station. The purchase is for .92 acres of land.
The next Village of Bruce board meeting will be held 7 p.m., Monday, Feb. 1 at the Bruce Village Hall.