Sustainable Waste

Sweet potato fields in Eastern NC.
Bob Is Traveling / Flickr Creative Commons

Many farms spread human waste on cropland to fertilize it. In this case, the waste is called "biosolids". It can carry household chemicals that affect important bacteria, and that can hurt soil health.

The government has had a hard time regulating chemicals in biosolids, because the equipment that measured bacterial gases was very expensive.

But a new report from Duke University's school of engineering shows that bacterial reactions to chemicals can be assessed by changes in color. That's a cheaper test to administer.

Trash at a state landfill.
N.C. Division of Waste Management

The amount of garbage headed to the Wake County has dropped significantly in the past few years.

In 2009, the county buried 460,000 tons of garbage. That dropped to 400,000 last year.

Wake County Solid Waste Manager John Roberson says a number of factors impacted the reduction in waste going to the landfill: People bought and threw out less during the recession, recycling options improved, and commercial waste businesses disposed of garbage elsewhere.

Roberson says his division saw a $2 million drop in revenue over the past four years.

Raleigh has opened what it calls the nation's most sustainable solid waste services facility. The new operations center was built to LEED platinum standards - the highest level of sustainability certification. City manager Russell Allen says the building was constructed with re-used and recycled materials where possible. It includes solar panels and geothermal systems; and will have plug-in electric vehicles.

Orange County and UNC Chapel Hill are working together to make productive use of a landfill gas. Methane originates from the decomposition of organic materials such as food. The collaboration will collect methane from the county's landfill and use it to produce electricity using a generator at UNC. Ray DuBose is the director of UNC Energy Services. He says projects like these are not without precedent.