SIOUX FALLS — Travis Entenman stood on the banks of the Big Sioux River in central Sioux Falls on an early April afternoon, watching the future flow.

High winds swept through Falls Park, the city’s namesake, as he spoke of downtown development and a master plan for the park that will showcase a stretch of the 419-mile-long tributary that weaves through South Dakota’s largest city.

“I’m hopeful that we can get the river to a place that the whole community can be proud of,” said Entenman, managing director of Friends of the Big Sioux River, a nonprofit that works to protect and restore the river and its watershed. “I think we’re trending in the right direction, but there’s a lot of work to do.”

Much attention has been paid to high levels of E. coli bacteria that make parts of the Big Sioux unsafe not just for drinking water but recreational uses, primarily the result of agriculture and livestock operations upstream.

But there are also concerns with water pollution from hazardous waste tied to the city’s meatpacking legacy. Looming directly to the north as Entenman unfurled his vision was Smithfield Foods, the sprawling pork slaughterhouse formerly known as John Morrell.

It’s hard to discuss the health of the Big Sioux River in these parts without mentioning Smithfield, which slaughters nearly 20,000 hogs a day and processes a daily flow of 3 million gallons of wastewater, containing varying levels of toxic materials.

How much waste does the processing plant dump into the Big Sioux? According to the Environmental Protection Agency’s most recent Toxic Release Inventory, which uses 2022 data, Smithfield ranked first nationally among 1,671 facilities within the food sector for total releases, with 4.9 million pounds.

Smithfield ranked seventh nationally among non-poultry animal slaughtering facilities for the amount of nitrate compounds released. The TRI tracks the waste management of toxic chemicals that “may pose a threat to human health and the environment.”

Treatment facility reduces waste

The good news is that conditions have changed since 2022, partly due to pressure placed upon Sioux Falls’ fourth-largest employer to curtail its toxic waste.

Smithfield went operational with a new $45 million wastewater treatment facility in May 2023, reducing the amount of nitrate compounds released into the river.

The company's nitrate discharge to the Big Sioux River was 47% lower in 2023 than it was in 2022, said Ray Atkinson, senior director of external communications for Smithfield, which is based in Virginia and owned by Hong Kong-based WH Group Limited.

"The new state-of-the-art wastewater project reinforces Smithfield's proactive approach to implementing sustainable systems that improve environmental quality and benefit the community," Atkinson said in a statement to News Watch.

"The $45 million investment we have made in Sioux Falls is one of the largest infrastructure projects to have a direct impact on water quality in the Big Sioux River and has significantly reduced nutrient discharges and improved water quality in the Big Sioux River basin."

The update was tied to a permit renewal in 2020 that signaled a new chapter in government regulation and public scrutiny of the slaughterhouse. Smithfield has been fined for ammonia and nitrate dumping over the past few decades but avoided significant action from state or federal authorities.

In addition to basic environmental concerns, influence plays a role.

Downtown Sioux Falls enhancements such as the Steel District and East Bank show developers are regarding the Big Sioux River as a valuable resource rather than an eyesore, which means more expectation of oversight.

“I think the general public is starting to pay more attention to water issues, which helps turn the tide,” said Entenman. “There’s also increased money in development going on in central Sioux Falls. People are putting millions and millions of dollars on the banks of the Big Sioux because they see it as a benefit for the community. And they don't want to live next to a polluted river.”

Smithfield fined for toxic releases

The South Dakota Department of Agriculture and Natural Resources (DANR) fined Smithfield $53,382 in 2018 for violations of its discharge permit stemming from a wastewater treatment failure. The breakdown allowed exceedingly high levels of ammonia – at one point more than 20 times the state-allowed daily limit – into the Big Sioux River.

Smithfield was also fined $44,000 in 2011 for consistent violations of permit limits, including 26 ammonia release violations in 2010.

Those penalties continued a trend of sanctions that environmental groups viewed as proverbial slaps on the wrist for a multinational company that reported $14.4 billion in revenue in 2023.

Though the Big Sioux River typically has enough volume to dilute the effects of toxic waste, violations of ammonia limits always raise red flags, said Jay Gilbertson, manager for the East Dakota Water Development District, which promotes conservation and proper management of water resources.

Ammonia can be mitigated by adding oxygen to convert it to nitrate, which is less toxic but still potentially damaging. Excess amounts of nitrogen can cause an overgrowth of plants and algae and can be harmful to infants and pregnant women if ingested by blocking the blood’s ability to carry oxygen.

New permit includes nitrate limits

The problem with Smithfield’s treatment system until recently was that, even with conversion, massive amounts of ammonia lead to troublesome levels of nitrates.

The EPA’s safety standard for nitrates in drinking water is 10 milligrams per liter.

Before its new wastewater treatment plant was operational, Smithfield’s nitrate dumping levels were “well over 100 (milligrams per liter), frequently over 200 and at times approaching 300,” said Gilbertson.

Those numbers, combined with earlier ammonia infractions and EPA reports, finally forced action. After two decades of having its permit with the state “administratively continued” every five years, meaning DANR guidelines stayed the same, the slaughterhouse finally faced a bona fide permit renewal in 2020.

Under the old permit, originally issued in 2000, there was no daily effluent limit for dumping nitrate into the Big Sioux. Smithfield was required to “monitor and report” levels of discharge, similar to how the Sioux Falls Water Reclamation Plant currently operates.

New treatment system unveiled

The new permit, which took effect July 1, 2020, gave Smithfield three years to get in compliance with an effluent limit for nitrates. That limit, which is currently in place, is a maximum of 50 milligrams per liter for a 30-day average and 88 mg/L daily.

Smithfield made its wastewater treatment plant upgrades to meet the new effluent limits by July 1, 2023. The new system takes the nitrates that were drawn from ammonia and uses a denitrifying system to biologically convert them to nitrogen gas, which is much less harmful.

Data from the EPA’s Enforcement and Compliance History Online (ECHO) shows that hazardous waste from the slaughterhouse has stayed below required limits since that time.

Atkinson told News Watch that Smithfield is currently operating at or below 40 milligrams per liter for nitrates on a monthly average and that the company's ammonia discharge has been reduced by about 60%.

Dana Munyon, a public affairs specialist with DANR, confirmed that “Smithfield has met the compliance schedule deadlines as required in the permit and no effluent violations of ammonia-nitrate have been reported during the current permit cycle."

This story was produced by South Dakota News Watch, a nonpartisan, nonprofit news organization. Read more in-depth stories at sdnewswatch.org and sign up for an email every few days to get stories as soon as they're published. Contact Stu Whitney at stu.whitney@sdnewswatch.org