SAN TAN VALLEY — On certain days, when the air moves the right way, residents living in neighborhoods near the Johnson Utilities wastewater treatment plant off Hunt Highway rush to shut their windows, pull their kids inside, and plug their noses to avoid the putrid stench that descends upon their homes.

Despite their efforts, they cannot shut it out and are sometimes even woken up at night by the smell. One resident described the stench as like the inside of a porta-potty in the heat of summer at the end of a three-day music festival.

While residents were warned that they would be living near a wastewater treatment facility and that odors might be an issue, they didn’t know that Johnson Utilities had received 108 violations for releasing higher concentrations of hydrogen sulfide gas than is allowed by federal law.

“You acknowledge that you’ll be living in a community next to a sewage treatment plant,” said Matt O’Connell, who lives near the facility. “But there was no indication in that disclosure that Johnson Utilities had over 100 hydrogen sulfide violations, which is a poisonous gas, over the course of two years. I think those are two very different things: smelling something that’s not harmful versus hydrogen sulfide gas.”

According to Occupational Hazards and Safety, acute exposure to high levels of hydrogen sulfide gas is a well-recognized hazard, but the effects of long-term chronic exposure are not well studied.

O’Connell has organized other residents to petition Pinal County, specifically the Board of Supervisors, to take further action on the issue which they feel has not been adequately addressed. The petition currently has 2,035 signatures.

While the county says that Johnson Utilities has only registered one violation (Jan.14) since July 24, residents say that the odor has only continued to get worse.

Mike Sundblom, director of Pinal County Air Quality, said there is no mechanism with which the county could take action against the utility outside of violations for hydrogen sulfide gas emissions. For the 108 violations between 2015 and 2017, the county settled on Aug. 21 with Johnson Utilities for $20,000 and an agreement that the utility would file a plan to change operations at the plant to keep hydrogen sulfide emissions within the legal limit.

The county could have fined Johnson Utilities $10,000 per violation, up to $1,008,000, but they would have had to take the case to court, and instead settled for $20,000.

“We are not focused on just fining people to fine people,” Sundblom said. “We want them to get into compliance.”

Johnson Utilities did get into compliance for hydrogen sulfide levels after the settlement except for the one violation in January that the county plans to address. Sundblom acknowledges that the smell may be worse, but said that the agency can’t do anything about odor.

“We don’t have a specific rule that odor can’t be above a particular level, and that’s the difficulty with odor,” he said.

The county does not test for any other gas concentrations.

“Hydrogen sulfide is the one thing we have a direct number to regulate that is an indicator of how things are operated at the facility,” Sundblom said.

In response to continuing complaints and the petition, Sundblom and other county officials met with affected residents on Jan. 19. Residents reported that different areas are hit with the smell at different times depending on a variety of factors. This led them to raise concerns that the monitoring may be faulty because it relies on monitoring hydrogen sulfide levels for a single site. That site is the maintenance facility for the golf club at Oasis owned by Johnson Utilities, even though the treatment plant has 28 open air treatment ponds.

“We believe it’s still representative of the general population in that area. We can’t be in all places at all times with monitoring,” Sundblom said.

Nevertheless, the air quality department still plans to add a monitor at an additional location in response to public demand. There is currently no time frame for when this will be added.

Sundblom encourages residents to file complaints with the Arizona Corporation Commission, the regulating body that Johnson Utilities answers to.

“It’s not that we have turned a blind eye to their concerns,” he said. “We are doing what we can on our side.”

Residents who are afraid that the stench invading their homes might be harmful to their health, instead of merely gross, feel that more needs to be done. They have set up a system to report and record odor complaints as they come in online. Since Jan. 13, 215 complaints have been submitted.

“It’s overwhelming. It’s like you’re not even breathing in oxygen,” O’Connell said. “It makes you nauseous and, you know, my wife’s pregnant and I don’t know the implications. And I asked the county this, I said the odor that we are smelling, can you guys say to everyone here today that you know for sure that this odor that we’re smelling is not a hazardous gas? And they couldn’t answer that question.”