As construction workers prepare to pour the foundation for a new Target store in Davis, a citizens oversight group is sounding the alarm about a recent discovery of a hazardous substance nearby.
Recent groundwater samples from an area 100 feet east of the planned location for the Target building revealed the presence of trichloropropane (TCP), a synthetic chemical that the U.S. government considers a hazardous substance.
The samples were taken on the Target property, which sits directly east of an EPA Superfund cleanup site on Second Street in East Davis. The Superfund site was established after the Frontier Fertilizer company illegally dumped pesticides and other chemicals during the 1980s, contaminating soil and groundwater in the area.
Pamela Nieberg, president of the Frontier Fertilizer Superfund Oversight Group, sent a letter to the Environmental Protection Agency requesting more investigation into the discovery. The samples came from outside the Superfund site, where TCP has already been detected. The oversight group is concerned that the chemical could be coming from a different source, or that the contamination is spreading in an unexpected way that could harm Target employees or nearby residents.
“It is an issue of determining the extent and probable source of the TCP contamination, possible health impacts in the neighborhood and how to remediate if necessary,” Nieberg said.
The oversight group is calling for further groundwater sampling before the foundation is laid for the Target building.
“Once the slab is poured, that sampling will be difficult if not impossible,” she said.
EPA officials said they did not believe the discovery was enough to stop the Target project from moving forward.
“While it is our intention to further investigate the TCP found in this area, we believe that this additional investigation can occur either before or after the Target store is constructed,” said EPA project manager Bonnie Arthur.
TCP is a synthetic chemical that is typically used in the manufacture of other chemicals, according to the federal Department of Health and Human Services. In high doses, TCP exposure causes eye and throat irritation in humans. Other research has shown that extremely high TCP exposure in mice and rabbits caused damage to internal organs, but these results have not been reproduced in humans. It is not classified as a cancer-causing substance.
In a letter to the oversight group, Arthur noted that TCP has only been found in two of 40 groundwater sample locations on the Target property, neither of which were at the location of the building itself. Over ten years of sampling have shown that there is not enough of the chemical present to be considered a health risk to the community, she said.
The EPA is requiring Target to install a vapor barrier beneath the building to prevent any chemical vapors from entering the building through the foundation. Target has also built new monitoring wells to make up for wells that are being displaced by the new development.
A Target representative told the Davis Enterprise that it expects the new wells to be able to detect the contamination’s movement, noting that there are more wells now than there were before.
Construction on the foundation of the building is slated to begin this month, and Target expects the store to open in October.
JEREMY OGUL can be reached at email@example.com.