Firefighters discover toxic chemical

NASTY SURPRISE: A firefighter douses silage that spontaneously combusted, sparking a blaze that destroyed a 50m by 20m storage shed on a farm northeast of Dargaville.PHOTOS/DARGAVILLE FIRE BRIGADE

A fire safety officer is urging farmers to ensure toxic chemicals stored on their property are logged with officials to prevent potential harm to firefighters after 120,000 litres of a hazardous substance was discovered during a large shed fire on a farm near Dargaville.

Northland fire safety officer Craig Bain said a firefighter's job was dangerous enough without having to deal with large amounts of unexpected hazardous chemicals.

Mr Bain said that under the Hazardous Substances and New Organisms Act (HaSNo), farmers had to log quantities of hazardous chemicals.

But, he said, when firefighters turned up to fight a large blaze at a farm shed on Hoanga Rd, northeast of Dargaville on Tuesday, they discovered 600, 200-litre drums of tetraamminecopper sulfate in the shed.

Mr Bain said the fire was believed to have been caused by silage in one end of the roughly 50m by 20m 10-bay shed spontaneously combusting. Firefighters spent almost six hours bringing the fire under control after being called out just after 5pm, with embers igniting pallets at the site at 5.30am yesterday, sparking another almost two-hour call-out to dampen down the flames.

"It's a real concern for us. Farmers are supposed to log these hazardous substances under HaSNo so that when we are on our way there we can check to see what substances there may be. Also, this sort of stuff needs to be stored properly with a bund around it so if there is a spill it won't leak into the waterways," Mr Bain said.

He said there was no bund to contain the chemical - which while not flammable or combustible is highly toxic to fish, bees and some other species and is deemed a potential environmental hazard - and as some of the containers were melting firefighters had to use a nearby digger to form a trench to contain the leaking substance.

"They had to block one end of the ditch with dirt to stop the stuff leaking into the Wairoa River, which wouldn't have been very good for the fish there," Mr Bain said. "We always err on the side of caution when we get to [fires] but it can be very very dangerous if we are greeted by hazardous chemicals we didn't know were there. Some of these [hazardous substances] can cause major problems so it's important that we are aware when large quantities like this are being stored there."

WorkSafe New Zealand has been informed of the situation and is investigating, he said.

Mr Bain said despite the chemicals firefighters did a great job on the fire.

Dargaville chief fire officer Jeff Palmer said the lack of water at the farm hampered efforts to put out the blaze.

Water tankers were brought in from Paparoa, Hikurangi and Marsden Point to keep up the water supply while firefighters from Dargaville, Te Kopuru, Whangarei, Ruawai and Kamo, used the farm's swimming pool to fight the flames. Whangarei Fire Station's hazardous chemical unit was also used.

"We managed to save a forklift and some other implements using the swimming pool, but we'd just almost get it under control then we'd run low on water and the thing would take off again," he said.

A WorkSafe spokesman confirmed the organisation is investigating the Dargaville farm fire and had issued a hazardous substances compliance order in relation to the chemicals.