OLIVIA, Minn. — The Southern Minnesota Beet Sugar Cooperative met all of its environmental requirements in the 2019-20 harvest and processing campaign, despite it being one of the most challenging ever.
The harvest started later than any other. A wet, cold and muddy harvest meant higher volumes of water, soil and organic matter in the plant’s wastewater system. The late harvest also resulted in more partially frozen beets being lifted, adding to the challenges of storage at the cooperative’s 13 remote piling stations.
The cooperative managed to keep within the environmental parameters of its permit through it all, Sagar Sunkavalli, environmental engineer and the cooperative’s manager of environmental affairs, told the Renville County Board of Commissioners on Tuesday. He presented the cooperative’s annual report on environmental compliance, a requirement placed on the cooperative since it began discharging into County Ditch 45, or Sacred Heart Creek.
The report came as the Minnesota Pollution Control Agency opened public comment on a new permit for the cooperative’s operations. It has followed 11 years of negotiations between the agency and cooperative.
Southern Minnesota Beet Sugar Cooperative member-growers harvested 2.81 million tons of sugar beets last year, or roughly 98 percent of the crop. The factory in Renville sliced 2.61 million tons, according to information provided by Sunkavalli. He noted the cooperative was fortunate, as many other sugar processors in Minnesota and North Dakota were unable to harvest as large a proportion of the crop due to the wet conditions.
The challenges continued after the harvest. County Ditch 45 froze in mid-winter, and it was not possible to open it up, forcing the cooperative to hold more of the processed water on site. Overall, the plant treated 595 million gallons in the wastewater treatment plant and applied 55 million gallons on land through irrigation systems.
While the volumes at the plant were higher than normal due to the conditions, they were well below what would be expected. Steps taken to improve how water with high organic content is segregated from water with a lower organic content allows it to operate the wastewater treatment plant more efficiently, according to Sunkavilli.
The 2019-20 processing campaign continued until April 19, or about two weeks later than usual.
The cooperative continues to reduce the amount of phosphorus reaching the Minnesota River through its spring cover crop program. Since 2005, the practice is estimated to have kept 250,000 pounds of the nutrient out of waterways. The cooperated earned 14,632 phosphorus credits from the MPCA last year for it.
In response to questions from the commissioners, Sunkavilli said the possibility of a fall cover crop program is on the company’s radar, but not planned. There are currently no incentives for it from regulators, he explained.
The engineer reported that bio-monitoring performed by the cooperative in County Ditch 45 has shown that since discharges began in 2005, the cooperative has not had a measurable impact on organic life in it.
The most significant environmental compliance issue last season proved to be hydrogen sulfide emissions from the water storage ponds at the factory site. There were emissions that exceeded the standard of 30 to 50 parts per billion due to the high volume of water and organic matter at the site, Sunkavilli reported. He said the problem was exasperated by a number of days with little wind, which otherwise serves to dilute the gas.
The permit now open for public comment will allow the cooperative to increase its daily discharges into County Ditch 45 by 30 percent, from 2.3 million gallons to 3.6 million gallons. It would also allow discharges to continue into April, with the discharges to stop when water temperatures reach 13 degrees Celsius. It’s the point at which fish begin spawning.
County Board chair Bob Fox noted that there was “standing room only” in 2004 when the commissioners held a public hearing on the permit that moved the factory’s discharges into County Ditch 45. The cooperative’s management of its discharges have apparently improved. Commissioner Rick Schmidt, who represents the area, said he received “zero” complaints in the last year from landowners along it.
The MPCA will host an informational meeting on WebEx on the new permit at 4 p.m. Tuesday, Sept. 1. A public notice on the MPCA web page includes instructions on how to participate.