CHEYENNE — The Cheyenne Board of Public Utilities has identified Goat Systems LLC, the contractor working on the Meta data center campus under construction in the High Plains Business Park, as the source of emissions that introduced Cupriavidus gilardii bacteria into the city’s wastewater treatment system.
Frank Strong, manager of BOPU’s engineering and water resources department, told the Wyoming Tribune Eagle on Thursday that the contamination was discovered during routine testing in February.
According to the National Institutes of Health, Cupriavidus gilardii is a rare type of bacteria that occurs naturally in the environment, such as soil and water. Although it is usually harmless in nature, it can sometimes act as an opportunistic pathogen, meaning it mainly infects people who are already sick or have a weakened immune system.
As a result, BOPU temporarily suspended Cheyenne’s recycled water irrigation program, permanently revoked Meta’s wastewater discharge rights, and adopted a new policy prohibiting the discharge of wastewater from data centers using closed-loop cooling systems and fill-and-flush systems, which includes circulating treated water to remove debris, flux residue, and scale in the pipes, draining it, and refilling the loop with fresh coolant.
A Meta spokesperson told the Wyoming Tribune Eagle in an email Thursday that Meta supports the efforts of its prime contractor Fortis to resolve the BOPU issue.
“When the board reported that it had detected the substance in municipal wastewater rather than public drinking water, Fortis immediately stopped discharging industrial wastewater and began transporting it off-site,” the spokesperson wrote.
“Fortis also began its own water testing with an independent environmental specialist, which found no traces of the substance.
“Meta is committed to being a good neighbor to Cheyenne, including by protecting local water resources, and will continue to encourage cooperation between Fortis and the board of directors until this situation is resolved.”
Construction water is identified as a source
Strong said Goat Systems discharges fill and flush water into the city sewer system, and that the discharged water already contains Cupriavidus gilardii.
“As soon as we found out about the bacteria and then where it came from, we shut it down immediately,” Strong told WTE.
However, Strong said he doesn’t know where the bacteria came from. All BOPU officials know is that the water released by Goat Systems contained it. According to him, this water was purchased from BOPU.
Betsy Hale, CEO of Cheyenne LEADS, said she wanted to emphasize that the incident occurred during construction of the Meta facility and not while operating the data center, which is not yet online.
Hale also emphasized that Cupriavidus gilardii occurs naturally.
“It wasn’t something they created during construction,” Hale said. “It’s already there. It entered the system at a level that was monitored, detected and needed to be corrected.”
Bacteria detected during routine testing
Strong said BOPU did not specifically test for Cupriavidus gilardii. This was most likely discovered when staff performed routine fecal testing for bacteria.
“It’s not something we typically test for,” Strong said. “…We actually had to go through a whole process to figure out what it was.”
He noted that the incident was very unusual.
“We haven’t seen these bacteria before,” Strong said. “We are not aware of any other discharges of fill and flush water into our system.”
Because there is little information about the bacteria and its potential health effects, BOPU has taken what Strong says is a cautious approach.
He said Internet searches suggest there may be health risks for people with weakened immune systems, although information about the bacteria is limited.
Instead of immediately resuming water treatment operations, Strong said officials suspended the city’s water reuse system while more testing was done.
Why was the reuse system closed?
Strong emphasized that the incident did not impact drinking water in Cheyenne.
Instead, the city’s water recycling system was deployed, distributing treated wastewater to irrigate parks, golf courses and other public green spaces.
Strong said he was concerned that spraying treated water could infect people in green spaces.
“The concern we have with our reuse system is that we put it in an aerosol and then spray it on the grass, and that increases the potential for health problems,” Strong said.
Because of this possibility, BOPU has decided not to operate the recycled water system until testing confirms the absence of bacteria.
Officials have since tested both wastewater treatment plants and both sites came back negative, Strong said.
Recycled water irrigation has resumed and Strong said BOPU will continue to monitor the system.
Some bacteria have entered Crow Creek.
Although the recycled water system was shut down, Strong said the wastewater treatment plant was unable to remove bacteria from all wastewater.
As a result, some of the bacteria went through the purification process and ended up in Crow Creek.
Strong said officials believe the public health risk from the release is low because the bacteria occurs naturally and people are generally not exposed to Crow Creek in the same way they might be exposed to irrigation sprinklers.
New policy for data centers
In response to the incident, BOPU announced Thursday that it will no longer accept industrial wastewater discharges associated with fill-and-flush operations or closed-loop cooling systems used by data centers.
Erin Lamb, BOPU’s administrative and public affairs coordinator, said the decision will primarily impact future projects.
“I don’t think we have any other data centers that use fill-and-scrub technology right now,” Lamb said. “I think we have people willing to do it, but I think all modern data centers (use) evaporative cooling. I think this closed-loop system is pretty new for reducing water consumption.”
Strong said BOPU’s concerns extend beyond the bacteria Cupriavidus gilardii.
Closed-loop systems may contain glycol and other chemicals that municipal wastewater treatment plants are not designed to handle, Strong said.
Instead, BOPU now requires industrial companies using closed-loop cooling systems to construct separate collection systems so that any water from the cooling equipment or associated floor drains is directed to storage tanks rather than to the city sewer system.
Existing data centers are largely unaffected
Strong said BOPU is not aware of any previous power dumps from existing data centers.
He said Microsoft’s new facilities use evaporative cooling rather than closed-loop systems.
As for the Meta campus, Strong said the project involves multiple phases using different cooling technologies.
The first phase of construction uses a closed-loop cooling system, while the second phase will use evaporative cooling.
Investigation ongoing
Lamb said she and other BOPU officials understand the public’s interest in learning more about the incident, but noted they first need to verify the source of the contamination before releasing information.
“We understand the frustration and the public’s desire to know all this information,” Lamb said, “but we had to go through a process to make sure everything was done correctly.”
WTE requested additional records related to the incident through a public records request. BOPU officials said the request is being processed through the agency’s legal department.
So far, Strong said subsequent testing has found no remains of Cupriavidus gilardii at any of the city’s wastewater treatment plants. The recycled water system is back online, and Strong said officials will continue routine sampling while enforcing new discharge limits.
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