KEY POINTS:
A major civil contracting company has been stung by a $750 fine after an attempt to use an environmentally friendly road sealing product in the Waitakere Ranges came unstuck.
Run-off from the new product drained into a stream in the sensitive Waitakere Ranges Heritage Area when sealing gangs were caught out by unexpected downpours of rain.
The Auckland Regional Council waded in with an abatement notice. This called on Fulton Hogan to stop illegal discharge to ground or natural water courses in the Auckland region.
ARC pollution response manager Nigel Clarke yesterday said the abatement notice followed five incidents of run-off from the water-based bitumen emulsion product in the past six months.
In two cases, the product had run-off O'Neills Rd and reached natural waterways. The road is inside the boundary of the new Waitakere Ranges Heritage Act.
Mr Clarke said the discharges did not kill fish in the stream.
The company had assured the council it could manage use of the product elsewhere in the region.
ARC environmental committee chairwoman Dianne Glenn said: "This was a significant event. An abatement notice and infringement notice are not issued lightly. They are first debated by management and council."
Instead of the water-based product, in Waitakere the company has gone back to using a traditional type, which uses kerosene additives.
Fulton Hogan North Harbour regional manager Trevor Moir said the company was "caught out" by rain, shortly after spraying the bitumen and applying stone chips.
He explained the emulsion product as bitumen suspended in water as a delivery mechanism. The water evaporated, leaving just the bitumen on the ground. The heavy downpours triggered run-off, though it only contained a small amount of inert bitumen and no detectable chemicals.
Mr Moir said the ARC infringement was at the lower end of the penalty scale showing that run-off was not significant.
"We dobbed ourselves in to the Pollution Hot Line. That is duty of care. We are responsible if we breach resource management rules. You are not allowed to discharge anything into the natural environment."
He said recent spills highlighted the need for strict management regimes and these were now being implemented on sites.
"We are working with the ARC, which will review our work procedures so it is comfortable with our processes and controls."
Waitakere was a high-risk area for the water-based product.
