Odors come after storm-caused power outage at plant
Officials hope foul smell will subside now that damage from recent rain has been repaired
Clear days after the rain early this month brought folks in El Segundo outdoors, the city's mayor said at a recent City Council meeting, but the air smelled bad.
And residents say it still does.
That's because the Hyperion Water Reclamation Plant was remedying some damage caused by those recent storms at the facility. The odor though, mostly caused by hydrogen sulfide, is something that the community has dealt with since a massive sewage spill three years ago at the plant.
Heavy rain on Feb. 4 and 5 caused an overflow of about 1 billion gallons of water into Hyperion, which overwhelmed the facility's pumping system, El Segundo officials reported at the Feb. 6 council meeting. Hyperion is meant to handle a maximum of 800 million gallons.
The storm caused a power outage in the truckloading facility, which affected some of the equipment, said Tonya Shelton, spokesperson for Los Angeles Sanitation and Environment, the agency that oversees Hyperion. Repairs were completed Feb. 17, however, and Hyperion crews performed pre-storm assessments to prepare for this week's rain.
Shelton said that intermittent, increased odors are emitting from the plant due to the rain damage and a slowdown of the water treatment process, from the primary tanks to the secondary clarifiers. Los Angeles Sanitation and Environment, the agency that runs Hyperion, expects the smells to subside in a week or two following the repairs, she added.
To immediately relieve the site, though, Hyperion on Feb. 5 discharged treated water through its 1-mile outfall pipeline for 45 minutes, city officials said, the maximum time allowed under the plant's operating permit.
The 1-mile outfall gates are otherwise used monthly as required by the permit for preventative maintenance, Shelton added.
Hyperion had to use that 1-mile outfall, too, when it discharged 17 million gallons of raw sewage into the ocean in July 2021. During
that incident, the plant became backed up and flooded with raw sewage, nearly crippling the region's largest and oldest wastewater reclamation facility and plaguing the surrounding community.
On Feb. 5, though, Hyperion also flared off biogas to counteract the rain damage, LASAN said in a recent notice.
The week following the incident, El Segundo residents continued to call Hyperion to report ongoing stench, and complain in a
Facebook group for the surrounding community that it smells so bad, people are itching, have watering eyes and are gagging.
City officials said that Hyperion staff was making extra efforts to reduce odor release during repairs.
Other projects that were already underway and mandated in an order of abatement by the South Coast Air Quality Management District to quell the hydrogen sulfide odors, meanwhile, are to be complete by June.
To prevent raw sewage from spilling during the recent overwhelm, according to an LASAN's notice, Hyperion turned back on Primary Battery Tank D, which was shut off in December so that its cover can be replaced by the June deadline outlined in AQMD's order. The tank, one of four of which remove solid debris from the wastewater, was since put back offline, LASAN said in the notice.
Cleaning of the battery began this week and is set to continue through June 6, and by the end of that month, Hyperion is to finish putting the new lid on. Covers on the other three tanks were replaced last year.
But the cleaning schedule's intermittent nature, El Segundo City Manager Darrell George said, leaves a significant window within which odors may or may not waft through the city.
AQMD also issued two notices of violation to Hyperion on Jan. 28 and Jan. 30 for excessive odors.
George said that AQMD officials told him that the odors on those days came from the washing of Battery D. Doors were left open in multiple buildings where loading takes place, areas that George said are “pretty stinky.”
The problem, though, George said, was that the city didn't find all that out directly from Hyperion itself.
El Segundo got a flurry of complaints from residents on those violation days, he added, and soon after, AQMD reported the NOVs to the city.
That's also when LASAN officials told George about the equipment damage and subsequent outfall relief.
“We've made it known they need to continue to be transparent with us,” George said.
Hyperion did notify L.A. County Public Health about the damaging activity, Councilmember Carol Pirsztuk said at the meeting, but the people need to be notified just the same. And, she added, it would go a long way for the community to be able to know ahead of time when cleaning, maintenance and other things that cause odor will take place.
AQMD, meanwhile, extended Hyperion's order of abatement from the end of January to Aug. 30 so that its hearing board can review the fixes one last time after everything is complete in June.