Cedar Grove Composting’s third annual “Compost Days” are running now through April 15 in Marysville and Arlington, as well as the rest of Snohomish and King counties, to reward the region’s residents for diverting 350,000 tons of food and yard waste from landfills in 2012.

Those in Snohomish County can join the scavenger hunt to find “Corey,” the compostable apple core, whose secret codes will appear on posters at 15 participating Snohomish County retail locations, including the Fred Meyer at 9925 State Ave. in Marysville, as well as the Haggen stores at 3711 88th St. NE in Marysville and 20115 74th Ave. NE in Arlington.

A map of Corey locations can be found online at www.compostdays.com.

Those who find Corey will win coupons for free bags of compost and a chance to participate in the “Big Dig” event, digging through a school bus-sized pile of compost for up to $1,000 in prizes, happening at the Lynnwood Fred Meyer on March 30 from noon to 4 p.m.

“By having their food scraps and yard debris collected for composting, Puget Sound residents prevented more than 350,000 tons of organic material from being sent to the landfill last year,” said Tim Croll, solid waste director with Seattle Public Utilities. “That’s equivalent to eliminating a 100-mile-long train full of garbage from being sent to the landfill. Thanks to their efforts, we are keeping gardens, yards and parks in our communities green and healthy.”

Cedar Grove Composting will donate more than 60 yards of compost from the Lynnwood and other upcoming “Big Dig” events for community gardens, as part of their ongoing commitment to make generous compost donations to community gardens and organizations throughout the Puget Sound.

“We’re so proud that our communities are at the forefront of composting,” said Candy Castellanos, public education and outreach manager for Waste Management. “When you put your food scraps, food-soiled paper and yard waste in your food and yard waste carts, you make compost. Compost reduces water use and the need for chemical pesticides, while boosting the fertility and growing power of the soil in your yards, gardens and farms.”

“With more plastic, paper, cardboard and aluminum being recycled by residents than ever before, food scraps and food-soiled paper are the largest contributors to area landfills,” said Pat McLaughlin, director of the King County Solid Waste Division.

For more information on “Compost Days,” log onto www.compostdays.com.