Transport for NSW says the discovery of cancer-causing coal tar in Hunter Street will not affect the cost or timing of light rail construction.
The tar, which gives off a pungent smell when dug up, was widely used as a binding agent in asphalt during the 1970s and 1980s, especially in Sydney and Newcastle.
It is classified as a carcinogen under Safe Work Australia guidelines, and the International Agency for Research on Cancer lists it among 120 “Group 1” substances which cause cancer in humans.
The National Cancer Institute says occupational exposure to coal tar or coal-tar pitch is associated with an increased risk of skin cancer and that other types of cancer, including lung, bladder, kidney and digestive tract, have been linked to the substance.
A Hunter Street shop owner told the Newcastle Herald that he was not aware of coal tar being found but the air “absolutely stank of tar” in the first two or three days of work outside his store this month.
He said he had seen a black, wet substance in the material dug up outside his shop and had felt slightly nauseous at the end of each day.
Unions NSW spokesman Peter McPherson said the discovery of far more “nasties” than predicted had prompted fresh negotiations between head contractor Downer EDI and the state government over the cost of the light rail project.
But a Transport for NSW spokesperson denied that an excess of contaminants had brought Downer and the government back to the bargaining table.
The spokesperson said the discovery of coal tar had been “expected” and had not affected the 2.7km light rail’s price tag, which stands at $290 million, not including $200 million to shut down and repurpose Newcastle's heavy rail corridor.
This odour occurs when the coal tar asphalt is milled and the friction heat from the milling machine releases coal tar fumes.- RMS website
Asked what measures contractors were taking to ensure the safe removal of contaminants, the spokesperson said: “All handling of coal tar is undertaken in accordance with NSW Health and NSW Environment Protection Authority guidelines.”
Mr McPherson said Unions NSW was happy with the way the contaminated material had been handled and disposed of.
He said contamination had been an issue for both the Supercars and light rail civil works. Construction tenders of this nature typically allowed for an amount of contamination handling, but both projects had revealed far more contaminants than forecast.
He said civil works for the light rail had been delayed at the start, but the same finish date, September this year, remained in the contracts. He stressed that the September date was for the finish of civil works, not necessarily the entire project.
Hunter transport engineer Ron Brown supplied the Herald with a photograph of what he identified as viscous coal tar dripping off a slab of excavated concrete in Hunter Street.
He said coal tar was still visible in the street on Wednesday.
The NSW Roads and Maritime Services website says coal tar “may still exist as a road surface layer but is more commonly found as a discreet subsurface layer overlaid by more modern bitumen asphalt”.
“The most obvious way most Roads and Maritime workers identify the presence of coal tar asphalt, as distinct from bitumen, is the distinctive odour it gives off when heated,” it says.
“This odour occurs when the coal tar asphalt is milled and the friction heat from the milling machine releases coal tar fumes.
“Cancer risk can be managed with appropriate work processes and personal protective equipment.”
The RMS says the chemicals that make up coal tar have been found to cause serious skin irritation and photosensitisation, increasing the risk of sunburn, if protective equipment is not used.
The agency, after a risk assessment in 2007, decided that excavated coal tar must be taken to a licensed landfill and not re-used for any purpose, although the risk to the public when coal tar was re-used in road construction was “negligible”.
The website directs workers to stop work immediately if they find coal tar, wash exposed skin, apply sunscreen and wear overalls, impervious gloves, safety glasses and respirators.
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