POLICE are ‘assisting’ Guernsey Water in an investigation into a bitumen spill that has polluted borehole supplies near the airport.

The incident happened at Lagan Construction’s south compound in November.

But Guernsey Water has only this week admitted that there has been contamination.

However, the utility said it had not posed a health threat to anyone who drank the water.

Guernsey Water added that water storage was at capacity and none was being transferred to the reservoir.