MINNEAPOLIS (WCCO)– The Minnesota Pollution Control Agency was under fire in a hearing Tuesday for approval of a water quality permit requested by PolyMet last year.

An attorney for the MPCA denied any wrong-doing, but challengers argue that the permit was issued despite concerns, and that those records were destroyed.

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PolyMet wants to build a copper-nickel mine in St. Louis County, and despite being awarded permits, they have been in and out of court ever since.

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“We didn’t destroy documents. If there was something that was relevant to this proceeding, we did not destroy it. And certainly if there is something that should have been in the administrative record under the regulatory boundaries that we’ve talked about, they saved that document,” a member of MPCA’s legal team said.

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The judge has asked each legal team to put together their final arguments, and the trial will continue Wednesday.