Feeding "The Big Pig" and saving the planet

She's a lactose-intolerant vegetarian — and the kids at Covington's Crestwood Elementary School know just how finicky she is. Every day at lunchtime, they sort her chow, putting leftovers like cookies, bread and fruit into paper-bag-lined buckets.

She's bEARTHa, the first Earth Tub composting system in a King County school. And three dutiful fifth-graders tend to her daily after they've eaten.

The bEARTHa boys — Zach Barlow, Christopher Katsafanas and Evan Sullivan — meet at the gym, gather the food scraps into a larger container, weigh and record its contents, then pour the mishmash into bEARTHa after checking the temperature of the compost inside. It's a repetitive chore that one of the boys says is worthwhile. "To keep trash and stuff from going into the landfill," Evan said.

Through a partnership between King County's Solid Waste Division and Crestwood, bEARTHa arrived in 2004 as part of the county's three-year pilot program for on-site food-waste composting. Other organizations are testing different composting methods.

Crestwood, one of five organizations using an Earth Tub in this program, has helped show that the bEARTHa system is the easiest to use and most effective for medium-scale composting, said Kinley Deller, the county's waste-diversion specialist. The county paid for 75 percent of the system's initial cost, but this year the school takes ownership of bEARTHa, which students call "The Big Pig." The Earth Tub, made by Green Mountain Technologies, is an enclosed system for composting food waste and looks like a giant round Tupperware container — the size of a hot tub — with a rotating lid.

For several minutes, the boys spin bEARTHa, mixing the new scraps with the decomposing mound, while a mechanical shaft also turns. They may add woodchips or water to get the proper consistency. For the process to work well, the materials need to be moist but not soggy. The contents "cook" inside the tub — bEARTHa works best at 120 to 140 degrees — until they're removed and bagged as compost at the end of the school year. The school then sells the compost back to the community for gardening. To keep bEARTHa from smelling up the area outside the cafeteria, there's a biofilter, a plastic trash can with wood chips and some finished compost, that pulls air out of the Earth Tub with a small fan.

"One of the things we had to convince the little kids of is that they have to eat first — before they feed bEARTHa," said Crestwood principal David Staight. "They get so excited."

bEARTHa fits in well with the school's rigorous recycling effort; Crestwood joined the county's Green Schools program in 2002. In seven months, the school reduced water use by 60 percent — 172,040 gallons — by installing low-flow toilets, no-water urinals and a rain barrel, said program manager Dale Alekel.

Crestwood students recycle cellphones, printer cartridges, cardboard boxes, lunch trays, milk cartons, water bottles, aluminum cans, paper and even plastic grocery bags.

But the roots of Crestwood's movement go back further.

Longtime Crestwood physical-education teacher Wendy Shol — who now works at Bellevue's Bennett Elementary School — championed bEARTHa's arrival. In 1996, she founded the school's Defenders of the Planet environmental club.

"In order to help save the environment, we need to teach the kids at a young age the do's and don'ts for recycling and composting and conserving," she said. "Because they, then, become the teachers to help the adults change their habits."

Judy Chia Hui Hsu: 206-464-3315 or jhsu@seattletimes.com