Crews installed two new monitoring wells at Roberto Clemente Park in Brentwood in an effort to gauge damage to groundwater caused by illegal toxic dumping.

The 60-feet deep monitoring wells will test samples to determine whether the groundwater is safe, as required by the state Department of Conservation.

Islip town officials say they have been frustrated with a lack of progress in getting the agency to clean up roughly 50,000 tons of construction debris at the park.

Town officials say three other monitoring wells were installed in September. Testing from those wells has come back with clean water samples. Islip Councilman John Cochrane says the hope is that water testing from the two new wells will also come back free of any contaminants. At that point, the town would hire a company to begin carting the toxic debris out of the park and replace it with clean fill.

Residents and civic leaders say they still do not know when the park will be open again to the public.

The DEC has not returned calls from News 12 to comment on the progress at Roberto Clemente Park.

The park is one of four sites in the Suffolk district attorney's investigation into illegal dumping in the Town of Islip and neighboring communities. Last month, six people were charged in connection with the dumping scandal.