Analysis of the silt from Peel harbour showed the material does have levels of metals which are higher than normal - but in line with where it came from.
That's according to Chief Executive of the Department of Environment, Food and Agriculture Richard Lole.
Earlier this week the Department of Infrastructure started dredging the silt from Peel harbour and transporting it to a specially lined dumping area at Poortown.
The move sparked anger from Peel residents after a number of spills on roads in the town, and German Commissioners are due to host a public meeting on the issue tomorrow (Thurs) evening.
Infrastructure Minister Phil Gawne has admitted the department could have explained itself better.
Speaking on Today's Talking Heads programme, Mr Lole said the analysis of the silt was carried out last year to see if it was safe to dispose of the material at sea.
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