Groundwater for Once-Through Cooling

General Mills vs Minnesota DNR

The Minnesota Department of Natural Resources has been working for many years on a program to reduce the amount of clean, drinkable groundwater used for once-through cooling systems. This pumped groundwater is run through a building's air conditioning system one time, and then dumped into surface waters. General Mills, at its headquarters office complex in Golden Valley, was, up until 11-Jan-2001, not only 'not' planning to reduce usage, it actually had plans to 'increase' pumping. Currently, at this site, they pump about 250 million gallons per year, and they planned to increase this amount to about 350 mgy.

Minnesota state law requires all once through cooling systems (OTCS) of more that 5 million gallons per year to stop operation by the end of year 2010 - or at the end of the determined lifespan of their equipment, whichever comes first. General Mills (GM) had applied for a special exemption from this law, and wanted to operate for as many years into the future as they wished - possibly forever.

The DNR stood firm with the state law, and denied GM's request to continue this form of groundwater usage. The DNR believes OTCS is wasteful and unwise use of a valuable natural resource that should be protected for higher purposes and for future generations. The Met Council, Mpls Parks Dep't, Sierra Club, Mpls Planning Dep't and others agreed with the DNR and submitted letters of concern on the issue.

Stating that it should be not be denied a special exemption from the state law, General Mills actually filed a lawsuit against the DNR. Since its inception in 1989, the state law has been obeyed by approximately 70 firms, which have converted from OTCS to a more sustainable form of air conditioning. Many of us feel that a special exemption for General Mills would have been very unfair to these 70 firms that have done the right thing, and have played by the rules. It was good news to hear on January 11th that General Mills had decided to drop the lawsuit, and would convert from once through cooling.

One, and only one, firm, H.B.Fuller, has requested and received a special exemption from this state law. However, this one precedent is about 45 times more generous than was the General Mills plan. As a net benefit provision, GM would have provided about 27 acres for a public park nature preserve area within the City of Golden Valley. The H.B.Fuller nature park is 265 acres - 9 times larger. At approximately 70 mil. gal/yr, the H.B. Fuller pumping amount is 5 times smaller than the planned 350 mgy with General Mills. Factoring both the park size with the pumping amount, the General Mills offer was about 45 times weaker than the one prior exemption. The nature preserve, in and of itself, was a good idea, but not with the aquifer water pumping and dumping deal attached.

General Mills had offered to spend hundreds of thousands of dollars on park related improvements in and around this proposed public nature preserve in Golden Valley. There had also been talk of GM donating about 4 acres of public park land for ballfields. The City of Golden Valley had intervened in the lawsuit and had actually filed legal papers in support of General Mills.

The Golden Valley municipal water system is hooked into the City of Minneapolis river water system and does not rely on groundwater pumping. Thus Golden Valley may not have as much reason to be concerned about groundwater depletion as does a great number of municipalities in the Twin Cities area. Sixty-six municipalities in the metropolitan area rely on groundwater pumping for their public drinking water systems. This list of cities includes the near Golden Valley neighbors of St. Louis Park, Plymouth, Edina, Minnetonka, Hopkins, Orono and Brooklyn Center. This area is expected to continue to grow in population and development, so the demand for drinking water will undoubtably increase.

In the EAW, General Mills brushed off the concerns of their discharge causing any creek ecosystem degradation. However, many of us wanted an Environmental Impact Statement for a more indepth study of these issues.

Chlorine was confirmed in the EAW as a chemical added by General Mills to the OTCS water. General Mills had confirmed in other communications that they also add the chemical ortho-phosphate. Many of us felt that this omission, of any mention of the chemical additive ortho-phosphate, was a serious violation of the mission of the EAW. This begged the question, were any other chemical additives not mentioned in the EAW? I, for one, wanted to see credible research documentation proving that the OTCS discharge caused no harm to any of the creek ecosystem's plant or animal species, such as nymphs, mussels, crayfish, or blandings turtles.

Does thermal pollution cause any problems? The 50 degree aquifer water is heated in the process of passing through the air conditioning system. On very hot days, this water has been reported as high as 90 degrees F at the point of discharge. Usage of over 4 million gallons per day have been reported in very hot weather.

In addition, part of the discharge flows through stormwater runoff treatment ponds, reducing water retention time; thus reducing the pond's effectiveness in removing pollutants.


Please click on the items below to learn more about this issue. This list contains the most relevant comments on this issue that I have been able to obtain and digitize or link, thus far:


----- If you have any questions, comments or suggestions on this issue, or on this website, feel free to contact me, Dave Stack, stack@mninter.net , 329 Russell Av. N., Minneapolis, Mn, 55405 (612--377-4096).

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