Florence could cause an environmental disaster in North Carolina, where waste from hog manure pits, coal ash dumps and other industrial sites could wash into homes and threaten drinking water supplies.

Two decades ago, a Category 2 hurricane caused dozens of hog manure pits to flood as millions of gallons of untreated sewage spilled out. Florence is forecast to make landfall in the same region as a much stronger storm.

North Carolina has roughly 2,100 industrial-scale pork farms containing more than 9 million hogs.

The Environmental Protection Agency says it will be monitoring nine toxic waste cleanup sites.

Also of concern are more than two dozen massive coal ash pits operated by Duke Energy.