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A detoxified and newly designed Harrison Street Skate Park project may soon be rolling again after the discovery of contaminated groundwater halted construction last November. 

The City Council will consider a request from the city manager for $115,000 to complete the clean up of contaminated groundwater and $50,000 to hire designers to develop new skate park plans. Lisa Caronna, director of Parks and Waterfront, said if the funds are granted the new plans could be ready for review this month. 

The skate bowls, nine-foot-deep concrete skating areas, were being excavated last November when the carcinogen chromium 6 was discovered in groundwater that had seeped into the bowls. Construction was stopped and the City Council approved emergency funding of $100,000 for the removal and treatment of the water. 

Some 120,000 gallons of contaminated water was removed from the site and another 80,000 gallons are currently being stored in four enclosed tanks adjacent to the site, according to Hazardous Materials Supervisor Nabil Al-Hadithy. 

Al-Hadithy said some of the additional $115,000 being requested from the City Council will be used to treat the groundwater in the tanks with iron sulfate, which will render the chromium 6 into a benign form known as chromium 3 or metallic chromium.  

Once treatment is complete, the groundwater will be released into the sanitary sewer system. The city is in contract with the environmental engineering company SECORE Inc. to carry out the groundwater treatment. 

Al-Hadithy said the treatment plan was complex to design. “It really was a great deal of work,” he said. “We worked with outside chemists and chemical engineers to develop the plan.” 

In addition to treating the groundwater in the bowls with bisulfate, the bases will be filled with crushed rocks and sealed off. Al-Hadithy said the bisulfate treatment would provide an added margin of safety. 

“Once completed there will be no route of exposure,” Al-Hadithy said. “It will be double and triple sealed.” 

City officials would like to have the work completed as soon as possible. According to a staff report, Harrison Field, immediately north of the skate park, is scheduled to open for adult soccer teams on Feb. 18. Youth soccer is scheduled to begin on March 11. 

The soccer field use does not depend on the decontamination of the skate park area. 

A temporary fence has been erected around the skate park site and signs have been posted in English and Spanish, warning soccer players to not enter the construction site. 

Because of the contaminated groundwater plume beneath the skate park, the design will have to be changed. The Parks and Waterfront Department has requested $50,000 to redesign the bowls so they rest above ground. 

Caronna said the city will hire a skate park designer and a structural engineer to create the new design. She said the two excavated bowls on the east side of the park will probably not be re-designed. 

“We should be able to save about 50 percent of the work already done,” Caronna said. “But the two bowls to the west will probably have to be raised.” 

The estimated cost of the Skate Park is $400,000, which is only $20,000 more than the original budget according to the staff report prepared by the city manager. 

However, if the cost of the toxic clean up is added to the overall cost of the skate park, the project is about $235,000 over its original budget.