PORTER | A metallic sheen was reported Wednesday afternoon on Lake Michigan in the area of Porter Beach.

Bruce Rowe, supervisory park ranger and public information officer for the Indiana Dunes National Lakeshore, confirmed that the Porter Fire Department was dispatched about 1 p.m. to Porter Beach.

Rowe said early indications are that the sheen is similar to one reported June 17 in the same area. However, he said it is too soon to know if it is the same substance.

Dan Goldblatt, spokesman for the Indiana Department of Environmental Management, said his office was aware of Wednesday's situation and that IDEM employees were at the lakeshore collecting water samples.

Goldblatt said Wednesday IDEM's investigation of the glittery film found floating near the Porter Beach shoreline June 17 is not complete. IDEM officials have the raw data back from the laboratory where the samples were sent, and IDEM employees are still analyzing that data, he said.

IDEM and U.S. Coast Guard representatives said the plume June 17 was 2 miles long and a half-mile wide, but quickly disappeared. It is unclear whether it dissipated or sank to the bottom of the lake.

Preliminary test results showed the substance to contain tricalcium orthophosphate, an anti-caking agent used as a food additive and in industrial products.

Swimmers on Wednesday were not asked to leave the water.

John is the Porter County editor for The Times. He is a Region native and graduate of Valparaiso University. He has worked for The Times since 1996 and previously worked for newspapers in Jasper and Newton counties.