The proposed natural gas pipeline would stretch from Siler City to Moncure in Chatham County.
Investigators said the deaths "appear consistent" with a murder-suicide, though the investigation remains active.
Also Monday, a grand jury returned 2nd-degree murder indictments on the man driving the boat and his girlfriend, the boat's owner
The documents say Quentin Kight admitted to driving the boat when it hit people swimming near an anchored boat, killing a child and injuring a woman.
The family of the 10-year-old girl who was killed in the incident released a statement Tuesday night.
A judge kept AnneMarie Flanigan's bond at $500,000 after she was deemed a flight risk.