Blenheim drinking water not at risk

Tests show Blenheim’s drinking water is not at risk, as a new investigation is launched into the use of banned, toxic firefighting foam at two air force bases.

Blenheim’s water supply was tested as quickly as possible last week after the New Zealand Defence Force said it had found levels of soil and water contamination at Woodbourne and Ohakea air bases from the historic use of the firefighting foam.

Marlborough District Council water experts sampled three wells at the water treatment plant on the corner of Middle Renwick Rd and Colemans Rd and a fourth at Bomford St.

Engineer Stephen Rooney said they had looked for the agents known as PFOS/PFOA in the foams used in fire drills at the base. None were found.

‘‘We also undertake sampling to show compliance with the Drinking Water Standards for NZ,’’ Rooney said. ‘‘We test for e.coli daily in the Blenheim water supply. We also take samples to show the water chemistry from all of the wells.’’

Nelson Marlborough Health medical officer of health Stephen Bridgman said they were pleased the council arranged to test the town’s drinking water supply. ‘‘This result gives us reassurance about the current drinking water supply.’’

PFOS and PFOA chemicals were ingredients used in firefighting foams, but use of all foams containing them was banned in New Zealand in 2006 due to their toxicity. There were worries the chemicals could contaminate water.

Property owners around Woodbourne and Ohakea were told on December 7 Defence staff wanted to take water samples from wells, drains or streams on their properties for testing. They were offered alternative drinking water while tests were conducted. In addition to risks to Blenheim’s 25,000 residents, about 90 properties near Woodbourne were affected and 70 at Ohakea.

On Wednesday, the Environmental Protection Authority said it had joined other organisations in determining where and when the chemicals were used, and how far the chemical runoff had spread.

The authority’s investigation would look into whether the foams were still being used, or were still held at airports and other places, and how and where they were stored.

‘‘Provided these foams are appropriately stored, they pose no immediate risk to people or the environment,’’ EPA spokesman Michael Pearson said.

The testing of private water sources by Defence on some properties neighbouring the base was also continuing.