Peri Park Playground was shut down last week after fleas were found in the sand and wood chips, prompting concerns from parents and grandparents who frequent the park.
"It's really scary," said Fairfax resident and grandparent Debra Zibitt. "I'm afraid little children will go in there. It'll hurt their legs, they're so tender."
Town officials believe raccoons living beneath a nearby building are the likely source of the infestation.
Workers are currently sealing off access beneath the structure to prevent the animals from returning.
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"We have a worker now exposing the area and sealing the area," said Fairfax Building Official Mark Lockaby. "The raccoons can escape, but it doesn't let them back in."
Eliminating the fleas presents a unique challenge because Fairfax prohibits the use of pesticides on public property under a town ordinance. Instead, officials are pursuing a nontoxic treatment plan.
"It looks like we're going to use a company that steam cleans everything," Lockaby said. "They'll steam all the sand and chips, and that's supposed to kill the fleas."
Parents who visited the park Monday said they support the closure until the problem is resolved.
"Let's get out of here," said parent Kristin Raymaker. "We have a 3 year old and we definitely want to avoid fleas if we can."
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Officials with the Marin/Sonoma Mosquito and Vector Control District, which is not involved in the cleanup effort, say flea activity has been increasing this summer.
"Because of our humidity, things get warm, and it's a good environment for fleas to expand their terrain and increase their numbers quickly," said district manager Peter Bonkrude. He noted that female fleas can lay between 20 and 50 eggs per day, allowing populations to grow rapidly under favorable conditions.
After the steam cleaning process is completed, town staff will monitor the playground to ensure the fleas have been eradicated. If the treatment is successful, Fairfax officials say Peri Park Playground could reopen as early as Aug. 7.