In 2015, the department promised to move it by 2020
The infrastructure minister has questioned the value of digging up the silt buried at Rockmount, which his department wants to leave in the ground.
In 2015, the DoI had promised the contaminated material from Peel Marina would only stay at the site off Poortown Road for five years.
It's now applied for permission to leave the silt in the ground, claiming moving it would cost around £500,000.
Tim Baker says with the material safely stored and monitored, he sees no reason to dig it up:
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