Mixed use affordable housing project moves ahead

SANTA CRUZ >> The County Board of Supervisors on Tuesday passed a measure that will give the State Department of Finance more time to review a mixed-use affordable housing project poised to be built at 1500 Capitola Road.

The project would include 57 affordable housing units, a Dientes dental clinic, as well as a Santa Cruz Community Health facility. The development is also slated to include a public plaza and community garden.

The property, which is currently owned by the Santa Cruz County Redevelopment Successor Agency, is pending sale to MidPen Housing, a nonprofit developer that specializes in building affordable housing.

Tuesday’s extension comes after the county voted to reduce the price of the 3.7 acre parcel in a November board meeting by more than $2 million because of environmental concerns. High levels of dry cleaning solvents and petroleum byproducts have been found in soil vapor and groundwater at the 1500 Capitola Road. site.

Weber Hayes & Associates, an environmental consulting firm retained by the county, has documented one such contaminant — tetrachloroethylene, or PCE — in soil vapor at levels ranging from 100,000 micrograms per meter cubed, to 1.5 million micrograms per meter cubed.

Those soil gas detections are orders of magnitude beyond state board residential and commercial health and safety standards, which are 15 and 67 micrograms per meter cubed, respectively.

PCE is a known human carcinogen, and exposure over the long term is linked to neurological disorders, various cancers, and kidney diseases. While no residents live on the development property currently, it still poses a risk to future community members.

“If people are exposed to even very low levels of PCE chronically, meaning you’re breathing it every day in your home, it’s harmful to your health,” Jim Wells said, a geologist with L. Everett & Associates, and an expert in soil vapor contamination.

PCE has also been detected in groundwater beneath 1500 Capitola Road property; In at least one sample the contaminant was found at 192 parts per billion, more then 38 times the state board’s threshold. Benzene has also been found in soil gas at 330 micrograms per meter cubed,

which exceeds the California Department of Toxic Substances Control benzene ambient air standard by over 300 times.

“Vapor intrusion is this phenomenon whereby toxic chemicals that are spilled into the ground, usually as liquids, volatilize, and then those gases waste up through the soil and they can seep into buildings,” explained Wells.

The contaminated vapor moves through small spaces between soil grains.

“If you go out and water your garden, how does that water get into soil?” Wells said. “It’s seeping through those pore spaces. Soil gas is the air that’s filling up the spaces between interconnected soil particles.”

Contaminated vapor can also sneak into buildings through utility lines, or cracks in a building foundation.

The high levels of PCE likely stem from a dry cleaner that operated at

1600 Capitola Road in the 60s and 70s, though the water board is still actively investigating the source of the contamination, Dan Niles an engineering geologist with the Central Coast Regional Water Quality Control Board told the Sentinel.

“All the evidence that has been gathered so far points to a release from a former dry cleaner, that has migrated from that dry cleaner under the development property,” Niles said.

Before the construction of the mixed-use property could begin, the redeveloper, likely to be MidPen, would be required to implement engineering controls that suck contaminated soil vapor out from underneath the property, and redirect the air outside, preventing it from entering the building.

Throughout the construction process, the developer would need to pay for monitoring and testing to confirm if one such system lowers PCE concentrations to levels that aren’t harmful to human health, according to the water board. While these controls can be effective

in the interim, Wells said in the long term, the system doesn’t replace a cleanup of the toxic chemicals in groundwater and soil.

“These mitigation systems are going to help — they’re going to reduce exposure to indoor air by some level — but it’s not going to solve the underlying problem,” Wells said.

And it might be years until a cleanup happens.

The former dry cleaner, which now operates as a laundromat, sits directly to the east of the proposed affordable housing site at 1500 Capitola Road. The state water board has ordered the former dry cleaner owners to investigate contamination on their property and in adjacent areas. If charged with cleanup, those owners may be responsible for also mitigating contamination at 1500 Capitola Road.

But it’s still early — at this point it’s still unclear where funds would come from for a cleanup. According to Wells, these remediating dry cleaning sites can take decades, or longer.

And building the neighboring affordable housing development before fully investigating the contamination in the area at large, is risky, Wells said.

“There needs to be a more thorough investigation to fully understand the nature and extent of contamination on the redevelopment site, as well as the source area, on the dry cleaning side, because how do we know there’s not a wave of even worse contamination making its way in groundwater?” Wells said.

While the 1500 Capitola Road site is currently unoccupied, to the east lies the Live Oak Elementary School, a supermarket and residential neighborhoods.

At this point, the impact of the historic use of dry cleaning solvents to drinking water supply, soil, and air in those areas is unknown, according to Dan Niles with the state board. Those investigation results will be forthcoming.

“We’re anxious to see what the data shows,” Sheila Soderberg, with Central Coast Water Board said.