ASHEVILLE - In a push to ramp up recycling the city started its Zero Waste AVL program in 2012, featuring blue single-stream recycling carts.

The bins meant residents no longer had to separate different types of recyclables and could toss in a wider range of materials.

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Still, there are materials the program doesn't accept, such as plastic grocery bags, styrofoam and hard plastics such as toys and flower pots. Those have been appearing with greater frequency, causing problems with processing machinery and hurting sales prices, said Asheville Solid Waste Director Jes Foster.

"Contaminants like plastic bags can get into loads of recycling that our vendor needs to sell, which can cause a load to be rejected or to earn a lower price," Foster said.

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Here's a list of things that shouldn't go into the blue city recycling bins: