The Parks and Waterfront Department released an environmental study Wednesday on the proposed Harrison Street Skate Park nearly seven months after discovery of a chrome 6 groundwater plume halted work on the project.
The study, or Subsequent Mitigated Negative Declaration, explained that its intent was to “describe the re-design of the skate park in light of the Hexavalent chromium (chrome 6) found in the groundwater and to provide for public view of this information.”
The study reviewed actions the city has taken and solutions implemented since the discovery of the chrome 6 plume.
Since the Stop Work Order was issued for the 18,000-square-foot skate park in November, the city has spent at least $295,000 in cleanup and re-design fees. Ed Murphy, project manager for the skate park said the cost of city staff time has not been estimated yet.
One city commissioner said the additional costs could have been avoided had the Parks and Waterfront Department followed normal procedures.
“As soon as the skate park design called for digging nine feet down for the skate bowls, the city should have ordered a study of the groundwater,” said Community Environmental Advisory Commissioner LA Wood. “When you do things backward you end up spending more money and that so far has been the legacy of Harrison Field.”
Parks and Waterfront Director Lisa Caronna said her department went forward with the project based on a 1999 initial environmental study that did not indicate there was chromium 6 in groundwater below the construction site.
But the 1999 study did not consider the excavation of the skate bowls, which had not yet been planned.
“Let me just say that we had been involved with the site for four years before the project began and we did testing, testing and more testing,” Caronna said. “But we are not avoiding the fact that we made a mistake.”
The skate park is located at Fifth and Harrison streets immediately adjacent to the Harrison Soccer Field. The soccer field and skate park are flanked by Interstate 80, train tracks and a variety of industrial businesses.
Chrome 6 is a Class A carcinogen that is harmful if swallowed and especially dangerous if inhaled, according to Environmental Protection Agency. According to the study, the groundwater in the skate bowls contained levels of chrome 6 between 1,200 and 2,100 micrograms per liter.
A December study by the Emeryville-based SOMA Corporation determined that there was little threat to humans because the site had been closed off and there were no apparent pathways for human intake.
Problems for the skate park began last November when groundwater flowed into pits being excavated for the bowls. Bill MacKay, one of the owners of Western Roto Engravers Color Tech on Sixth Street, happened to be across the street from the site, noticed the water and immediately notified Toxics Management Department that the water may contain chrome 6.
MacKay suspected the presence of the chrome 6 because his company was responsible for the plume. He said he reported the plume to the city in 1990 and has since spent nearly $1 million to remove the responsible tanks from his shop and monitor the plume’s movement, which he regularly reported to the city.
Since the discovery, the city hired private toxic management contractors to haul away 45,000 gallons of contaminated water and another 80,000 gallons were stored next to the site in 20,000 gallon tanks where it was treated and released into a nearby storm drain, according to Hazardous Materials Supervisor Nabil Al-Hadithy.
Murphy said the clean up of groundwater was completed Thursday.
According to the study, the skate park design has been altered so the five bowls will be mostly above ground. In addition, Murphy said the excavated bowls were compacted with gravel, covered with thick sheet of plastic and will soon be covered with six-inches of concrete to assure the groundwater is completely sealed off from the surface area of the skate park.
“Ideally we’d like to have the park completed something this year,” Murphy said.
Two air quality studies are about to begin at Harrison within the next week. One will monitor airborne particulate matter generated by the heavy traffic on Interstate 80, diesel fuel emissions from trains and the garbage transfer station at Second and Gilman streets.
The other study will monitor the air over the park for chrome 6. Murphy said the results of the studies won’t be available for at least a year.
“We have spent more money evaluating the environmental conditions of this site and know less about it that any other site I know of,” Wood said.