The clank and moan of chains knocking against tetherball poles provides a lonely soundtrack for the empty playground at Yakima's Hoover Elementary. Near a sign that urges kids to "Read More this Summer," the monkeybars emerge from bare dirt. Pink ribbon flutters around     exposed sprinkler heads, and off to the side of a soccer goal sits a two-story mountain of dirt covered with black plastic and sandbags. In the soil underneath the tarp are levels of arsenic nearly four times Washington's threshold for requiring cleanup; there's lead there, too, at nearly three times the threshold.

Over the past five years, Washington's Department of Ecology has overseen remediation of 20 out of the 35 schools in the central part of the state where lead and arsenic levels exceed state cleanup standards. Here, construction crews are removing 1,135 tons of soil to be taken to a local landfill. By the time school resumes this fall, they will have put a barricade of geotextile fabric on the bare ground and capped it with clean dirt and grass sod. The price tag for just this one school: $239,000.

"That's an expensive lawn," says Mark Dunbar of the state's Department of Ecology as he picks up a long-buried white-and-blue marble from the denuded playground, reminding me to wash my hands after I touch it. "But what's the cost of just one cancer treatment these days? It's cheap insurance compared to that."

Even here, though, the scope of inquiry is limited. The Ecology Department decided to test only for lead and arsenic in schoolyards, rather than DDT and other legacy pesticides, because it's cheaper and because the agency didn't want to overwhelm the public, says Valerie Bound, the agency's regional section manager for toxic cleanup.

"When you know it's an old orchard, how far do you want to open the door? Once you have the lab results, you can't really ignore them," says Bound. "The scope of the problem is so large. You can't really clean everything up. You just have to prioritize."

The tests are expensive -- $100 to screen for a suite of pesticides and $20 per heavy metal, such as lead or arsenic. The cost underscores how difficult it is for homeowners to discover what might be lurking in their soil, since doing so requires separate tests of multiple samples from different places around their yards.

A composite of five soil samples taken from the Comptons' yard by High Country News revealed levels of DDE, a DDT breakdown product, at 0.6 parts per million -- roughly half of the EPA's cancer risk threshold -- and arsenic at 4.7 ppm, seven times the safe level in Washington and 67 times the levels recommended by California's environmental health agency. This is fairly normal in central Washington, where background levels of naturally-occurring arsenic are 5 ppm. Still, that's not much consolation for a pregnant mother. And because the samples taken were combined and tested as one owing to the cost, the pesticide levels are only an average of the sampled sites. So now the Comptons have new questions: Are there hotspots in their yard where pesticides exceed safe levels, perhaps due to a spill or an old storage area? Or is most of the yard relatively clean?

"This is worrisome," says Compton, after she receives the test results; it's late summer, and she and her son have been digging in the dirt for days. Even though the test came back within a zone deemed safe by government experts, she worries that future standards will be much stricter. Already California has set levels that are far more protective, based on the most recent research. (See "Backyard poisons?" this page.) So Compton has decided to be proactive, within reason. The only failsafe solution -- removing the topsoil -- runs a prohibitive $950,000 an acre. Instead, next spring Compton will build raised garden beds, line them with an impermeable barrier and fill them with clean soil. (See "How to play safe in the soil," facing page.)

Set against the onslaught of toxic chemicals in our world, legacy pesticides are just another problem to contend with. Possible threats lurk everywhere, from the kitchen-sink cabinet filled with household cleaners to the flame retardant-impregnated mattresses in the bedrooms. "I can't live my life completely freaked out about these things," Compton says. "You can only protect your kids, and yourself for that matter, from so much. You're always going to be living with a certain amount of uncertainty."

Even so, the urge to protect is strong. On a warm summer night, Compton and 13 other moms hover around a picnic table at Yakima's Franklin Park. It's piled high with baking soda, apple cider vinegar and vegetable glycerin.

"I know we all want to do something, to take action," Suzanne Noble, a local special-ed teacher, tells the small group, which meets monthly to discuss how to reduce their kids' exposure to toxic chemicals. Today's lesson, taught by Noble, is on how to make your own cleaning products.

Children bounce in and out of their mother's laps, distracted by the Fisher-Price toys scattered on the ground. Two little girls race each other across the grass, their hair flying in their eyes. They stop at the finish line -- a pine tree -- and roll down a slight incline, holding their bodies as straight as Tootsie Pops. At the bottom of the hill, one of them wipes her face, smearing mud and snot, and laughs into the evening.

This story is funded in part by a grant from the Fund for Investigative Journalism and by contributors to the High Country News Enterprise Journalism Fund.