Crook County residents fear mining company polluted their water. Here’s how Oregon investigated

Don Porfily first noticed the change in his tap water last March. Out of nowhere, it tasted bad, “like mud,” said the 84-year-old feed store owner.

He stopped drinking it. Then, the plumbing in his Central Oregon farmhouse went haywire. Spigots lost pressure. The washing machine broke and so did the fridge and the water heater. When Porfily lifted the lid of a toilet tank, he found a layer of thick black sludge.

He’s lived in the house for 26 years and has never seen anything like this.

His neighbors also grappled with mysterious calamities. Down the road at Ashley McCormick’s house, they went through three dishwashers in a year. At Billie Johnson’s dairy, a record number of calves had been born dead. Same story at Bryan Zednik’s place.

Now, at least a dozen residents in this agricultural valley near Prineville are worried about the safety of their only drinking water supply, which is pumped from the ground.

“A neighbor will tell a neighbor, and they’ll call and say, ‘You better come look: black in the toilet, taste in the water,” Porfily said.

He and others lay blame on a multi-billion-dollar construction materials company.

In 2016, Knife River Corporation leased 100 acres in the valley and started digging for rocks.

The company denies its sand and gravel pit is hurting the groundwater. It’s a titan in developing the West, with tens of millions in state contracts to build roads and bridges. Near McCormick and Byrd’s houses, it harvests materials used to make concrete. Knife River is nearly finished at the site but has plans to open a new mine nearby.

Neighbors are galvanized against this. Some say they’ve already witnessed broken promises from the company, all while state regulators have balked at groundwater complaints and ignored possible permit violations.

Neighbors feel the lack of oversight has effectively shifted the burden of proof from a huge corporation to a gaggle of local residents, a troubling dynamic that is now getting the attention of federal lawmakers.

A giant washing machine

People living near the mining operation, known as the Woodward pit, launched their own investigation last fall.

Porfily and others paid to have tap water samples analyzed at a lab. Results from a dozen homes near the mine show varying levels of manganese.

Depending on the concentration, this metal can cause a range of problems, from stained laundry to liver issues and neurological dysfunction.

In some wells, like Porfily’s and McCormick’s, the manganese levels were well above federal health advisory limits.

Knife River and state officials have said the element was there all along, a common geologic side effect of the volcanic eruptions that shaped the region. But residents and their advocates argue mining released previously undisturbed contaminants.

On a recent site tour, a leader from Knife River compared its operation to a giant washing machine.

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“We mine material from the field, and then we introduce it into this wash plant,” said South Central Division Vice President Chris Doan.

The wash plant scours dirt from the rocks so they can be sorted and shipped out to the company’s concrete mix plants, Doan explained.

“It goes into home foundations, slabs for buildings,” he said, “It goes into building roads and highways.”

The wastewater from the mining process ends up in a series of settling ponds. From there it evaporates, infiltrates back into the ground, or gets pumped back through the washing machine.

The Woodward pit is one of the company’s 51 mining permits in Oregon. Over the last decade, the company has been awarded nearly $57 million in state contracts, mostly through the Oregon Department of Transportation. Its footprint spans 14 states in all, with a reported $2.2 billion in annual revenue.

‘A mine in the middle’

Oregon regulators are now considering whether Knife River can expand in Crook County, population of 26,000.

If it’s permitted, the new pit would share ground with a determined opponent.

Dick Zimmerlee is a farmer who leases land inside the expansion area. He can see the existing mine from his house, and for the last two years has spent a lot of time and money trying to stop it from growing.

“It just chapped my backside that the Goliath could get away with running over everybody else,” Zimmerlee said.

At first, he was worried about the amount of water the company was allowed to take to run its rock washing machine.

“Now, that’s really the least of our problems,” Zimmerlee said.

He believes the land Knife River has already mined isn’t fertile for farming anymore, even though the company said it replaces any topsoil it removes. He accuses the company of digging deeper than its permit allows and burying things that disrupt the flow of water underground. Zimmerlee contends this caused drainage problems in his fields. He began to file numerous complaints with state regulators in 2021. Knife River has denied his allegations. In 2022, Zimmerlee too, found a black toilet tank.

He hired a hydrogeologist to assess the situation.

Jim Newton runs an engineering consulting firm out of Bend. He said until this site he’s always worked for mining companies, not opposing them.

“I’ve never worked for NIMBYs, to put it bluntly,” Newton said.

This year, he drove to find 30 domestic wells in the immediate area of the Woodward pit, noting their GPS coordinates. He reviewed about a dozen available water test results. Then, Newton laid the data out on a map. He found a pattern in which homes have higher manganese concentrations.

“What’s different from one side of the map to the other side of the map? There’s a mine in the middle,” he said.

Newton theorizes that miners removed the earth’s filtration system: the sand and gravel beneath the topsoil. Pre-mining, anything on the surface would have to percolate through that natural filter. If you take out those layers, Newton said, the groundwater becomes more vulnerable.

“All of a sudden that layer above the aquifer is very thin and more permeable, you don’t have that advantage of additional material to filter out things like fertilizers, or really anything that hits the surface of the ground,” according to Newton.

State permits limited the mining depth at the Woodward pit to 20 feet below the surface, and according to Knife River’s planning documents, groundwater flooded the pit well above that, in some places at just 7 feet below ground. At its proposed expansion, the company expects to hit even more water.

Digging in the water table agitated manganese that had long been suspended as a solid in the ground, Newton said. The mining allowed it to dissolve in the aquifer. Picture dropping a lump of sugar into a glass of water, he said.

“You can see the crystals. There they are. Then, you give it a good stir and they’re gone. You can still taste the difference.”

Debate over manganese risks

Manganese is one of the most abundant elements on Earth, and an essential nutrient in food. But, too much of it can be toxic.

In 2011 and 2014, studies found exposure to manganese in drinking water was associated with poorer memory, attention and motor skills in children. In 2020, researchers drew a link between exposure during childhood and attention-deficit hyperactivity disorder.

The studies documented neurobehavioral differences when manganese concentrations ranged from 120 micrograms per liter to more than 400 micrograms per liter.

Ten of the 13 wells residents had tested near the mine were at or above that threshold. All of them were above concentrations known to give water a bad taste and leave stains.

Despite the growing concern over manganese, federal clean water laws don’t apply to it. In decades-old guidelines, the U.S. Environmental Protection Agency advises that at 50 micrograms per liter, manganese can cause aesthetic problems that could stop people from using it. The EPA says manganese is a health concern at or above 300 micrograms per liter.

Three of the 13 Crook County wells exceeded that benchmark.

Other countries and public health organizations have recently adopted much stricter health standards.

In 2019, Canada lowered its maximum acceptable concentration to 120 micrograms per liter. The World Health Organization is considering lowering its health-based guideline to just 80 micrograms per liter.

Oregon follows the EPA’s 2004 guidelines. Oregon Health Authority public health toxicologist Dave Farrer said in an email exchange that other countries have added “very large safety buffers,” based on studies that exposed animals to exponentially higher concentrations than any of the regulatory health limits for people.

Anyone who isn’t an infant could safely drink water with up to 1,000 micrograms per liter for up to a year, Farrer said. Above that level, “It would be best for no one to drink it even for a day.”

‘Not a home’

Don Porfily said he drank from his kitchen tap for 25 years, until last fall.

The water recently contained 1,120 micrograms of manganese per liter, nearly four times the EPA’s health advisory level. That’s according to lab testing of a May sample collected by OPB, which also revealed arsenic above the federal maximum contamination limit.

In a sample from Porfily last year, a different lab found lower levels of manganese, at nearly 500 micrograms per liter. By then, he had already stopped using the water for anything except flushing the toilet. He said the sprinklers don’t run anymore because the pipes are so clogged.

“I haven’t got any water to speak of in the house,” he said. “It’s not a home.”

When his neighbor Ashley McCormick first sent her own tap water sample to a lab, it found 400 micrograms per liter of manganese. She’s since spent thousands on a new well pump and a filtration system to make the water more usable for her family of five.

The costly system is online, but the smell and discoloration remain. Subsequent testing paid for by OPB showed tap water manganese concentrations still above the federal aesthetic contamination level, at 160 micrograms per liter.

Her family doesn’t drink it anymore. She even stopped bathing her three kids in it. The water leaves stains, she said, and recently one of her boys came down with severe hives that doctors couldn’t explain.

Experts say manganese isn’t readily absorbed through the skin, but at this point, McCormick is freaked out.

“We just take super quick showers,” she said.

She has considered selling. Though, as a real estate agent, she knows she’ll have to disclose the water problems. It was once her dream home. Now, she wonders, “Who’s going to want to buy it?”

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Byran Zednik is also feeling done. He raises cattle in the valley. After having to cut a bloated, dead calf from its mother’s womb piece by piece, killing both— he sent a blood sample from the mother to a lab. The blood showed manganese levels outside the normal range, according to a text from his veterinarian that Zednik shared. He wants to get out of the meat business and focus on raising crops.

“We’re selling our cows because we’re not going to pass that into the meat,” he said.

Reluctant regulators

The problem for homeowners around the Woodward pit mining site is that there is no data on manganese levels before the mine opened. Real estate transactions in Oregon don’t require such tests, and without that information, it’s difficult to say if all the broken appliances, dead cattle and hives are attributable to Knife River.

State regulators have relied on this lack of data to dismiss complaints against the mining company, too. To independently assess the complaints, OPB reviewed hundreds of public records detailing the state response and spoke to key officials, geologists, Knife River representatives, eight residents living near the mine, and an independent expert on manganese.

Private wells in Oregon are not regulated. It’s a homeowner’s responsibility to know what’s in their drinking water, said Oregon Department of Environmental Quality spokesperson Laura Gleim.

Still, per DEQ rules, mining sites are not allowed to degrade groundwater. The agency can bring enforcement actions against polluters. Since 2015, DEQ has issued more than $330,000 in penalties against Knife River and one of its subsidiaries for water quality violations, including a $20,822 fine last year related to the Woodward pit.

But when it comes to investigating complaints about water pollution by mining operations, DEQ passes responsibility to a different state agency, one that has much closer ties to the mining industry.

The Oregon Department of Geology and Mineral Industries employed geologist Bob Houston for more than 20 years before he became an environmental manager for Knife River in November 2021.

The hire wasn’t unusual, Houston said.

“When I was in the [DOGAMI] role, we did have some staff that retired and then went back to private consulting,” he said. “There’s a boundary there that our integrity and our professionalism won’t cross.”

This year, DOGAMI officially concluded that the Knife River’s Woodward pit is not responsible for contaminating groundwater.

State records show DEQ staff didn’t initially agree with DOGAMI’s assessment.

“We lack critical evidence to prove/disprove contamination from the mining activities,” DEQ Water Quality Permitting Manager Mike Hiatt wrote in a Jan. 25 email to a supervisor.

By then, key DOGAMI staff had already made up their minds. They’d been aware of various grievances about the mine for a year before allegations of groundwater contamination surfaced.

Since December 2021, neighbor Zimmerlee filed complaints on a variety of issues and repeatedly pressed DOGAMI for a site inspection, to no avail. Instead, the agency asked Knife River to respond.

DOGAMI shelved that complaint without drafting a formal response to Zimmerlee, according to records reviewed by OPB.

Feeling ignored and frustrated, Zimmerlee bypassed DOGAMI last October and went directly to DEQ with water quality concerns. But, the environmental agency kicked the complaint back to DOGAMI.

Its staff was immediately dismissive, their emails show. They did not want to investigate at all, saying Zimmerlee did not include enough new information or evidence that Knife River was to blame. They said the metals turning up in local water test results – manganese and in some cases aluminum — aren’t associated with sand and gravel mining.

A history of complaints

Zimmerlee wasn’t the only neighbor to contact state regulators about the Woodward pit.

Karen Mikulski lives across the street, and she wrote to officials in November 2021 to allege Knife River dumped “hundreds of truckloads of concrete and asphalt” into the mine as filler. Mikulski also said she saw a hose pumping water from a pit into a nearby stream.

Within days of receiving the account, DOGAMI staff virtually met with Knife River representatives.

At that online meeting, the company reportedly said a few neighbors were organizing to oppose the expansion, and “their objective is to portray [Knife River Corporation] as bad operators,” according to notes DOGAMI staff took.

The company’s environmental manager Jeff Steyaert admitted water from a pit had flowed to a creek, though only for a fraction of the time Mikulski said she witnessed it. The admission would lead to a $20,822 DEQ fine.

Knife River also acknowledged burying concrete debris in the mined farmland, a possible violation of its permit.

In an interview this month, Knife River Northwest Technical Services Manager Matt Ropp initially denied the company had buried construction materials in the mine until confronted with DOGAMI records obtained through a public records request.

“I was not aware of that,” Ropp said.

In a subsequent email, he confirmed that staff buried 8,000 cubic yards of concrete — roughly 31 million pounds — in the Woodward pit between June and August of 2019.

DOGAMI spokesperson Alex Lopez acknowledged that burying the debris was “clearly inconsistent” with Knife River’s operating permit, but said any regulatory action would be DEQ’s responsibility, not his agency’s.

The agency’s hydrogeologist Bob Brinkmann said that, generally, it’s on mining operators to make sure they follow the rules.

“It’s like you have a driver’s license. You’re supposed to know what the law is and not speed excessively,” Brinkmann said.

Knife River responds

Knife River said it began quarterly monitoring of two residential wells near the Woodward pit before it opened in 2016. Those tests have shown the water is safe, according to Knife River, but neighbors and their experts say the wells aren’t actually located in areas where groundwater would flow from the mining site.

Last year, the company hired a water quality consultant, Amber Hudspeth, to summarize its data in a memo to DOGAMI. Hudspeth found the monitored wells hadn’t changed much in seven years.

She concluded that the manganese and aluminum turning up in other water tests was naturally occurring and the result of volcanic geology, or possibly related to historical land uses.

There has been gravel mining in this area before, and the Woodward pit is partially located on the site of a defunct lumber mill. Hudspeth also pointed to the presence of manganese in the city of Redmond’s well water supply, 20 miles away.

DOGAMI geologist Brinkmann agreed with the company’s conclusions. He said in an interview that the data show a pattern linking metals in groundwater to certain well depths.

Knife River geologist Bob Houston added another theory to the mix in a recent email to OPB. Houston said there are wells throughout Crooked River Basin with warm temperatures, according to DOGAMI data, and that geothermal activity could cause dissolved minerals to appear in water tests.

Knife River and state officials have also pointed out that Zimmerlee’s house isn’t in the path of the groundwater’s flow, yet he reports manganese detections and a black toilet tank.

When Hudspeth tested Zimmerlee’s water in 2022, she found much lower levels of manganese and aluminum than his own samples had shown. OPB’s 2023 testing did not find concerning levels of either metal.

“I don’t know that Knife River, as a private business, is the correct party to go beyond our operations in order to try to figure out why a person’s toilet is stained,” said Knife River’s Matt Ropp.

He encouraged people with concerns to bring them directly to the company, instead of regulators.

“We do our best to try to manage our operations and, and to communicate with our neighbors in order to minimize impacts to them,” Ropp said.

OPB asked Ropp if, as a way to restore goodwill with the neighbors opposing the expansion, the company would consider paying for residential water filtration systems without admitting fault.

Ropp said no: “I am not fond of the idea of buying people off.”

The price of non-disclosure

Adam Mikulski came to Knife River with concerns about its Woodward pit before it opened in 2016.

State records suggest those negotiations led the company to pay for a new well at Mikulski’s house, across the street from the pit. The driller initially listed Knife River as the owner of the well. The company’s name was later crossed out of the paperwork and replaced with Mikulski’s.

Knife River monitors that well now, and its data was used to support dismissing the recent groundwater complaints.

Mikulski won’t discuss the deal, he said, because of a non-disclosure agreement.

That didn’t stop his wife Karen from contacting DOGAMI in 2021 to report the company for illegal dumping, resulting in the DEQ penalty.

The agencies’ response left Adam Mikulski feeling cynical.

“They just take [Knife River’s] word for it and, and they don’t come out and check,” he said of the regulators.

DOGAMI has not sent an inspector to the site since June 2021, before the complaints began.

Mikulski said he regrets initially going directly to the company because there is no public record of his concerns, nor the promises made to smooth them over.

Lately, DOGAMI appears to be rethinking its conclusions.

On June 5, the geologist working for local residents, Jim Newton, got an email from the DOGAMI’s Executive Director and State Geologist Ruarri J. Day-Stirrat. It asked Newton to come to a closed-door meeting in Portland at the end of June.

The purpose is to discuss the manganese in Crook County’s water. Knife River and Hudspeth are also invited.

“There will be no other participants,” Day-Stirrat wrote to Newton. “I expect a series of slides laying out your data, your hypotheses, and a discussion of solutions based on your hypotheses.”

Meanwhile, two U.S. Senators want to shift the responsibility and expense of providing answers away from the local residents and their paid consultant.

On June 7, Democratic Sens. Ron Wyden and Jeff Merkley sent a letter to the EPA’s top Administrator Michael Regan, saying they “have a particular concern about a mine in Oregon that is currently seeking an expansion,” and calling on the agency to examine the groundwater allegations as soon as possible.

In an interview, Merkley, a former state lawmaker, questioned the thoroughness of DOGAMI’s conclusions, and the state agency’s objectivity in investigating the industry.

“I know from my time in the state legislature that DOGAMI is basically often an advocate for mining,” Merkley said.

He wants the EPA to do an independent investigation of the Woodward pit operation and its proposed expansion.