A riverfront property owner says he's been left with thousands of dollars in cement blocks with nowhere to put them. That's after P.E.I.'s Environment Department denied his proposal to have shoreline protection installed, citing concerns it would have a "detrimental effect" on a salt marsh at the corner of his property. "All I'm doing is trying to protect my property," said Mark Keizer, who lives with his wife along the Hillsborough River in Mermaid, with a view toward Charlottetown Harbour.