PUNTA GORDA — Charlotte County Commissioner Bob Starr said he plans to tell the federal agency conducting a study on phosphate-mining impacts to expand its scope to encompass urban and agricultural impacts, as well as those from strip mining, on the Charlotte Harbor estuary.

Russell Schweiss, spokesman for the Mosaic phosphate-mining company, said his company intends to comment that the study should use more accurate data to calculate a maximum potential drawdown of Horse Creek and other streams due to the mining. That’s because the study assumes the mines discharge no water, but in reality they do, he said.