OLIVIA — By most measures, this past year was an “extremely challenging year” for the Southern Minnesota Beet Sugar Cooperative and its shareholders, according to Sagar Sunkavalli, the co-op's manager of environmental affairs.
Producers harvested 2.37 million tons of sugar beets last year, and sliced 2.22 million tons of them, in comparison to a record 3.67 million tons harvested one year earlier. Producers saw an average yield of 20.2 tons per acre, compared to 30.6 tons per acre the prior year.
There was a silver lining in it all, according to Sunkavalli in a report he made Tuesday to the Renville County Board of Commissioners. Thanks to continued investments in improved wastewater processing at the factory in Renville and operational changes, the cooperative’s environmental compliance was among its best ever.
It had no violations for stormwater discharges from any of its 13 remote beet piling sites, according to Sunkavalli.
It continued to improve the quality of the water it discharged from its factory site into Renville County Ditch 45, the headwaters of Sacred Heart Creek. It lowered the average conductivity of the discharged water, a measure of the dissolved minerals or salinity of the water.
Sunkavalli said the reduced harvest certainly was a factor, but overall, he said improvements in operations and processing and a commitment to meeting environmental standards played the biggest roles. At the remote beet sites, staff literally hand-picked stray sugar beets to prevent stormwater issues.
At the sugar factory, the cooperative has improved its ability to segregate water in processing beets. The factory captures more sugar from the beets to use as product rather than allowing it to enter the wastewater treatment plant and ponds, where it contributes to treatment costs.
“It’s in our best interest,” said Sunkavalli. “We can’t be losing product.”
Saving 1 percent of the sugar content that might otherwise be lost from a 3 million-ton harvest can represent 30,000 tons of pure sugar, he said.
The cooperative is also removing more of the soil that arrives with the sugar beets, preventing it from reaching the treatment system and adding to costs by helping bacteria grow.
The cooperative also continues to help keep soil and the phosphorus that binds to it in the fields of producers and out of waterways. It continues to see nearly 90 percent of its producers participate in planting a cover crop in the spring.
Last year's cover crops earned the cooperative 16,350 phosphorus trading credits, as compared to 6,500 credits it is required to earn by the Minnesota Pollution Control Agency. It is unable to sell the credits since the demand for them exists in the lower Minnesota River watershed, and not in the upper watershed where the sugar beets are grown.
The cooperative was not violation-free last season. Sunkavalli said despite investing in chemicals to control hydrogen sulfide emissions from its wastewater storage ponds, the cooperative exceeded the 30 to 50 parts per billion threshold for emissions 20 times. That’s a 78 percent reduction from the average over the past five years, but up from 13 last year.
The cooperative continues to seek an amendment to its permit to discharge more water into County Ditch 45, in part to better manage its retention ponds. Sunkavalli said it is asking to increase its allowed daily discharge from 2.3 million gallons to 3.6 million gallons, and extend the discharge period into April. It currently is allowed to discharge from September through March.
The cooperative experienced significant interruptions in its ability to discharge into the waterway in January due to the severe cold. It invested thousands of dollars to remove snow and ice from the ditch, but with limited success, according to Sunkavalli.
The cold winter did have its advantages. The consistent cold kept beets frozen at the piling sites, reducing juicing issues, he said.
Overall, Sunkavalli said the cooperative continues to meet environmental standards for the watershed. The cooperative pays for a company to monitor the aquatic life in the county ditch and Sacred Heart Creek. It has found no measurable effects of cooperative discharges on the aquatic life since discharges into the system began in 2005.
The cooperative is required to provide an annual report on its environmental compliance as part of an agreement allowing it to discharge into County Ditch 45.