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Delano begins the process of removing carcinogens from the soil downtown

Posted: 4:58 PM, Jun 29, 2022
Updated: 2022-06-29 19:58:53-04
Soil Cleanup in Delano

DELANO, Calif. (KERO) — Back in 2008 that the Central Valley Regional Water Quality Control Board found the carcinogen tetrachloroethylene, also known as PCE, in downtown Delano's groundwater. That’s according to the Center on Race, Poverty & the Environment, a "national environmental justice organization providing legal, organizing, and technical assistance to grassroots groups in low-income communities and communities of color."

According to the Centers for Disease Control and Prevention's Agency for Toxic Substances and Disease Registry, tetrachloroethylene "is used as a dry cleaning agent and metal degreasing solvent. It is also used as a starting material (building block) for making other chemicals and is used in some consumer products."

Much of the tetrachloroethylene released into the air comes from the dry cleaning industry. Some Tetrachloroethylene may be released from dry-cleaned or consumer products. Tetrachloroethylene breaks down very slowly in the air and so it can be transported long distances in the air.

Contamination of soil can occur when tetrachloroethylene at a waste disposal site seeps out of the waste and into the soil. Tetrachloroethylene may evaporate quickly from shallow soils or may filter through the soil and into the groundwater below. It is generally slow to break down in soil because it is lipid soluble, which makes it absorb or bind to soil.

If you are exposed to tetrachloroethylene, continuously, over a long period of time, you may also be at a higher risk of developing certain types of cancer.

“PCE, when experienced very chronically, does has very severe impacts as both a carcinogen and also causes respiratory issues so there’s an immediate concern about making sure that the indoor air in these buildings that we can be comfortable that it returns to safe levels,” explained Ingrid Brostrom, the assistant director for Center on Race, Poverty & the Environment.

If you are exposed to tetrachloroethylene, continuously, over a long period of time, you may also be at a higher risk of developing certain types of cancer.

If you breathe in air containing a large amount of tetrachloroethylene, you may become dizzy or sleepy, develop headaches, and become uncoordinated; or you may become unconscious. Some people have died after being exposed in tanks or other small spaces, or after intentionally breathing in a large amount of tetrachloroethylene.

People who are exposed for longer periods of time to lower levels of tetrachloroethylene in air may have changes in mood, memory, attention, reaction time, or vision. Animals exposed to tetrachloroethylene have shown liver and kidney 6 effects, and changes in brain chemistry, but we currently do not know what these findings mean for humans.

Tetrachloroethylene may have effects on pregnancy and unborn children. Studies in people are not clear on this subject, but studies in animals show problems with pregnancy (such as miscarriage, birth defects, and slowed growth of the baby) after oral and inhalation exposure to tetrachloroethylene.

Starting Wednesday something is being done about it.

"Decades later, we’re finally seeing some cleanup start. And I really attribute it to the increased attention from community members who really pushed this as a priority," said Brostrom. "This is a lesson on long delay.”

On Wednesday, crews began using a soil vapor extraction system to remove the pollutants from the soil under downtown Delano.

According to the Environment Protection Agency, soil vapor extraction "involves drilling one or more extraction wells into the contaminated soil to a depth above the water table, which must be deeper than 3 feet below the ground surface. Attached to the wells is equipment (such as a blower or vacuum pump) that creates a vacuum. The vacuum pulls air and vapors through the soil and up the well to the ground surface for treatment."

The process traps PCE within charcoal. The charcoal, which sits within several green containers, will have to be changed out every week to remain effective.

“We are also concerned that there is PCE in the top layers of the groundwater and that is also at extremely high levels, thousands of times above the state standards. So the concern is that if it does reach the municipal water supply, that’s going to be very hard to remove, and very dangerous for folks and extremely expensive,” said Brostrom.

It’s what prompted the center and the Delano Guardians to reach out to Mayor Bryan Osario. He says a year ago they formed a community advisory group to ask the California Department of Toxic Substances Control to work more closely on decision-making with the group of community residents.

“I would like to acknowledge that this process has taken many years, but the good thing is that we’re moving in the right direction," said Osario.

According to the DTSC the bulk of the contamination exists between 11th and 9th Street in downtown Delano. They’re expecting to reach safe levels in the next five to ten years. They're hoping to also build A second soil vapor extraction system by the end of the year.

“We really want to make sure we’re putting these in the right place, at the right depths, and investigating the right things," explained Ryan Mitchum, an engineering geologist. "So although it has taken a while, we’re confident in our investigation now that we are ready and at a point where we can make these decisions and put in these remedies where they’ll be the most effective.”


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