Pollutants still pouring into estuary

BY ALICE COWDREY

Heavy metal runoff from Richmond industry polluting two waterways that flow into the Waimea Estuary is well above levels lethal to aquatic life.

A report from Tasman District Council resource scientists urging heavier monitoring and investigation of the contamination sources will be considered on Thursday.

It shows the most filthy and heavily contaminated waterways are Vercoes Drain and Jimmy Lee Creek along Beach Rd, which have high levels of heavy metals, "well above levels lethal to aquatic life".

This was confirmed by the absence of any macro-invertebrates sensitive to these contaminants, said resource scientists Jenny Easton and Trevor James.

The report recommends the council investigate the industries that discharge stormwater into the waterways, inspect hazardous facilities, and introduce compliance inspections of contaminated waterways.

During the investigation, council compliance staff found petrol being illegally discharged from a coolstore into Jimmy Lee Creek. This was being followed up by council staff.

Mr James said that although levels of arsenic and lead in the estuary sediment had decreased, zinc concentrations had increased since 1996. These were from vehicle brake lining and emission runoff, reflecting higher traffic density in Richmond.

Sediment tested at the Dynea drain culvert, used by Nelson Pine Industries, also showed "extremely high" concentrations of zinc.

"The current theory is that although the roof surface itself is coated with steel, when holes were drilled for the fastenings, the filing debris, containing zinc and cadmium, have accumulated in the stormwater system," Mr James said.

Nelson Pine Industries research and environment manager Phillip Wilson said he was surprised by the zinc levels. About one-third of the water off the roof was treated at the site and then sent to Bell Island for further treatment, he said.

Tests comparing zinc levels at different spots in Jimmy Lee Creek showed that between Hill St and Beach Rd, the levels had increased five times.

Over the same area, lead levels had increased fourfold and levels of chrome had doubled.

The ecological health of Jimmy Lee Creek at Beach Rd was "very poor", and only "pollution-tolerant" species such as snails and worms were found there, Mr James said.

No mayflies, stoneflies or caddisflies were found, which was a bad sign, as these ate algae, he said.

The report shows the sediments in rural and residential catchments have low levels of contaminants.

Waimea Estuary management plan steering group chairperson and Tasman councillor Glenys Glover said it was a "general wish" of the council to improve the standards of the water flowing into the estuary.

Further monitoring was something practical that could be done, she said.

Environment and planning committee chairman Michael Higgins said the report was good because it spelled out the current situation.

He said the council had been taking a harder line with industries leaving behind messes.

"All the industries there and the council knows that we have got to get it right, and everyone is working towards that."

- © Fairfax NZ News