Mill Valley Students Suffer With Stench Of Neighboring Sewage Plant

MILL VALLEY (KPIX 5) - A Marin County middle school has a smelly problem. Parents say the foul-smelling fumes coming from a nearby sewage plant is making their kids feel sick.

The Mill Valley Sewage Treatment Plant was built back in 1954. In 1972, the local school district constructed Mill Valley Middle School, right across the street.

"It smells like raw sewage or an outhouse that hasn't been taken care of in quite some time," said parent Linda Moll.

Students are used to some days being a bit fragrant, but lately the smell has gotten worse. Plant manager, Mark Grushayev says that's happening, ironically, because of a major renovation project that includes replacing an old carbon filter exhaust system for removing odors.

"Everybody's transitioning now to this new technology which is bio-towers…really considered to be state of the art," said Grushayev.

When the new bio-tower is completed on the site there should actually be less odor, but now, with the building opened up for construction, more unfiltered air is being released. The rotten egg smell comes from hydrogen sulfide, created in the sewage treatment process.

When KPIX 5 visited, there were places inside the plant where there was no smell, but in front of the school it smelled like rotten eggs.

"Some days are really bad, some days are OK," says Moll. "This is actually pleasant."

The air is being monitored every day and results have shown no toxic levels of gasses. It is just enough to be a huge nuisance. Grushayev says the odor reduction part of the project has been moved up to accommodate the school and he thinks things should improve. Still, he can't guarantee that there won't be any smell because it is a sewer plant.

"What I'm committing to is to provide best effort from the staff to contain…and make sure that we're not offending anyone with emissions from this facility," said Grushayev.

The new odor-filtering tower should be completed by the end of 2018.