SAN DIEGO -- The city of San Diego is looking for places to put trash in the event local landfills fill up, and one idea is to place garbage in residents' back yards.

City Environmental Services workers are conducting a study at the Miramar Landfill to see what types of food services items -- like plates, cups and spoons -- decompose the fastest. So far, results look good.

After only two weeks, items like clear plastic cups had nearly disintegrated and plastic plates looked flimsy. In 10 weeks, workers hope the items will be decomposed enough to add them to compost piles. San Diego residents can take the compost for free and use it in their yards.

However, it's not just any kind of plastic plate that can be used. The city is investigating the use of bioplastic items. Bioplastics are made primarily from corn starch, which degrade much faster than traditional plastic.

If successful, the city can add the items to its compost pile and keep it out of the Miramar Landfill. The landfill is expected to be full by 2019. The city can extend that lifespan by recycling more and using more in compost.

"We make compost mostly from yard waste, wood waste, green waste," said city recycling specialist Ken Prue. "Then we also take in food waste from institutional settings."

Those institutions include San Diego State University, Marine Corps Recruit Depot, the San Diego Convention Center, Point Loma Nazarene University, PETCO Park and SeaWorld. The city hopes to recommend food service items that can also be added to the compost. It could prevent the landfill from filling up too quickly.

The study is costing the city only $350.