The Edmonds School Board met for a study session Thursday night to discuss infill options for artificial turf fields as the district prepares to replace fields at Meadowdale and Mountlake Terrace high schools this summer.

Turf fields are typically filled with crumb rubber, but the health effects of using crumb rubber has recently come into question by activists, both locally and nationally. After some community members protested the Edmonds School Board’s decision to use crumb rubber infill on sports fields at the Woodway Campus, the Edmonds City Council last summer passed an 18-month ban on public athletic fields made with the material.

Federal organizations, like the Environmental Protection Agency and Centers for Disease Control and Prevention, have started analyzing crumb rubber to determine if carcinogens inside the materials can be absorbed by athletes.

While no study conclusively says crumb rubber is harmful to humans, there is no dispute that harmful chemicals are present in the rubber, which causes concern for some.

“The reason we’re doing this is because of the health concerns that have been raised,” Board Member Carin Chase said. “While we’re moving forward, it is good to keep in mind that the whole reason we’re looking at this is because those concerns have been raised and we need to take them seriously.”

In light of this, the school board met with design experts to discuss what those alternative infill products would be. No decisions were made Thursday night regarding what fields will actually be made of, as that decision will be made once construction companies bid on the projects.

By the end of the meeting, the board was most interested in receiving bids with crumb rubber infill as a baseline and three alternative infill products for comparison: a sand and cork mixture, crumb rubber coated in polyurethane, and a natural product that is typically a mix of coconut, rice husks and cork, but varies by the company.

Compared to the crumb rubber, each of the alternatives would be more expensive. Cost estimates were provided by two representatives for DA Hogan and Associates, an engineering and landscape company that specifically designs outdoor athletic fields, though the actual cost is expected to vary depending on the bid from a construction company. Based on the estimate, however, a sand and cork infill mixture would cost about $60,000 more per field than a crumb rubber field. A coconut and sand mixture would cost about $100,000 more per field, and a polyurethane coated rubber field would cost about $50,000 more per field.

Each alternative material has additional drawbacks. For example, organic infill made from coconut, rice husks and cork needs to be kept wet. If the field’s moisture content is not maintained at 40 percent, the field’s warrantee is voided. That means more maintenance labor would be needed to water the field, even in the summer time, not normally a district practice. It also means that, although there are not any visible puddles on the field, it would be wet if someone were to sit or fall on it.

This is the kind of field that was recently installed in the South Kitsap School District. Edmonds School District officials visited the field to see how it was performing and how it is maintained.

“We saw a man rolling around in a motorized wheelchair on the field, and you could visibly see water spraying out from beneath his chair,” Matt Finch, project manager with the Edmonds School District, said.

That could be a problem for the Edmonds School District.

“We don’t even water our grass fields in the summer,” Superintendent Nick Brossoit said. “They die.”

The district is facing budget concerns. The cost of maintaining the fields could be a bigger problem than the initial cost of purchasing the materials.

“We’re nickel and diming the general fund, so I really want to know what kind of hit we’re making on the general fund because that’s teachers and other core costs,” Board Member Ann McMurray said.

It would also require more brushing to stay level than crumb rubber. It also compacts faster than crumb rubber, so more infill would likely need to be added over the years.

Sand is too hard of a material to be used as infill by itself, but it can be used alongside other products. In sand and cork fields, a layer of sand is put down first followed by a layer of cork. The sand stabilizes the “grass” and the cork is a more forgiving surface for athlete impact.

This mix is the only organic infill option that does not require irrigation. It is also relatively inexpensive compared to other alternative infill products.

However, it also raises some concerns.

“It’s not nearly as dense as rubber, so I think it will be displaced easier so you’ll be brushing it more,” Dave Anderson, of DA Hogan and Associates, said. He also said it might be more difficult for athletes to find their footing on this infill.

It is also a very new material, so its long-term durability has yet to be seen.

“Whenever I consider a new product, I always ask to see someone who has had it in use for at least three years,” Ed Peters, capital projects director for the Edmonds School District, said. “I feel a lot better if it’s been through several cycles of use.”

With this type of field, they may not be able to find a field that is even that old to see how well it is holding up.

With both of these organic materials, there is also a question of how well they may feed microorganisms like bacteria.

“Bacteria is going to be more likely, in general, to grow on something that is organic versus something that is not organic,” Elisabeth Black, with EBM Consulting, said.

Meanwhile, polyurethane-coated crumb rubber acts mostly the same as crumb rubber and requires the same low level of maintenance, but at a slightly higher cost. The benefit is the coating may contain the chemicals found in the crumb rubber.

Other materials were also discussed at Thursday night’s meeting, but the board was not interested in them by the end of the night mostly because of cost concerns.

Capital projects employees will move forward with creating a bid form that asks for prices of fields with each of the four infill options. Meanwhile, district officials will also work to create an estimate of how much maintenance will cost each year. A decision on what the district uses will come after the bids have been submitted.

–By Natalie Covate