The Sunnyvale Sun
News
Toxic cleanup plan set to begin in downtown
By Cody Kraatz
Officials tried to soothe fears about a toxic plume under Sunnyvale's downtown, and detailed an interim cleanup plan on Nov. 1. About 10 residents came to the meeting, and some said they were still anxious.
"My mom's in real failing health right now. I'm wondering if I should get her out of there," said Jamie Mclane during the meeting. She lives at S. Sunnyvale and Iowa avenues and voiced unease about dust from the construction downtown.
Mclane was not satisfied with answers about PCE's health risks.
"It didn't really clue me in," she said of the meeting. "I'm going to go look on the Internet about the long-term and short-term effects."
The chemical, perchloroethylene, or PCE, came from three dry cleaners that were located in the eastern part of the Town Center redevelopment project, where concentrations are highest, more than 30 years ago.
The groundwater throughout the downtown is contaminated, but the vapors that seeped from the water into the soil and now into the air is the main concern.
"We don't see levels here at this site that would cause acute effects," said Stephen Hill, chief of toxic cleanup with the state Regional Water Quality Control Board, which will oversee and approve the cleanup. "We're mainly concerned about long-term exposure."
Officials emphasized that the pollution will not affect Sunnyvale's drinking water, which comes from elsewhere, but that the groundwater must be cleaned up because it is an important resource.
People can be exposed to PCE by working at dry cleaners, wearing dry cleaned clothes or using such chemicals as shoe polish.
Short-term exposure to high levels, not the case in Sunnyvale, can cause respiratory irritation, vomiting, dizziness and death. Long-term exposure can cause cancer, damage to the central nervous system and harm a developing fetus.
Cleanup plan
The developer's consultant designed a $1 million interim cleanup plan focused on the soil vapors. Future cleanup costs are uncertain, according to those involved.
Pending anticipated RWQCB approval in December, 29 dry wells will suck out the vapors, two carbon granule filters will clean them and a number of monitoring wells will remain under W. Washington Avenue and S. Sunnyvale Avenue to keep an eye on the plume.
Installation has already begun and the wells would operate for three to six months. The system will be mostly underground and all soil will be sealed in drums onsite.
The city and developer will split costs equally up to $2 million, but the city's share grows along with the price tag, up to 85 percent of costs above $4 million.
"These systems will be out of the ground and gone before development [of that part of the Town Center redevelopment] starts," said the consultant, Philip Smith of Treadwell & Rollo.
The scope of the groundwater problem is not fully defined, but cleanup set to begin in early 2008, probably by injecting a carbon source or bacteria into the ground to digest the PCE.
"This is an impressive amount of work that's been done in a relatively short amount of time," said David Weingaertner, a chemist with some experience in environmental cleanup, during the meeting.
His wife, Laurie Hughes, a Charles Street Gardens coordinator and Sunnyvale Cool Cities Team member, asked him to come so the groups would have an expert at the meeting.
The public can comment on the plan to the Regional Water Quality Control Board until Nov. 19. For contact information or to learn more, visit GroundWaterFacts.inSunnyvale.com.
