By Shelley Topp
The Isaac Road Community Association has criticised the long wait for a dust monitoring programme at Yaldhurst quarries.
The association is opposing Christchurch Ready Mix Concrete’s proposal to build a large quarry near their Eyrewell homes in Isaac Road. Spokesman Bud Caldwell said Yaldhurst residents had been lodging complaints about the dust from the quarries near their homes for 25 years.
“It is hard to believe the council, ECan (Environment Canterbury) and the quarry operators have taken these complaints seriously, otherwise steps would have been taken before now,” he said.
“New Zealand, unlike Australia, does not have a minimal distance requirement between quarries and residences. Naively, the Resource Management Act relies on the ‘goodwill’ of the quarry operator to mitigate the effects of their activities. This self regulation is ineffective. With regards to Yaldhurst, that could be seen as 25 years of ineffectiveness.”
The Yaldhurst monitoring programme was announced in a joint statement by the Canterbury District Health Board (CDHB), Christchurch City Council and ECan, on March 10.
ECan senior manager service and delivery Brett Aldridge said nuisance dust had been a “long-standing” issue in the Yaldhurst area.
“Late last year some Yaldhurst residents came to us with their concerns about the health effects of dust coming from the quarries.
“We agreed it was important we get a good understanding about the potential for health effects the community has concerns about, and there was a need to really understand the scale and magnitude of the risk of dust to residents,” he said.
“We started a testing process, including taking samples from a resident’s property.”
The tests showed that dust containing crystalline silica had been coming from the quarries. Work Safe NZ has identified crystalline silica dust as a “dangerous air quality contaminant” in the extractive industry. “Respirable crystalline silica is dangerous and can cause serious lung disease and is known to contribute to lung cancer,” Work Safe NZ said.
The CDHB’s Medical Officer of Health Alistair Humphrey said that exposure to “unacceptable levels” of mined silica in the long term could have serious health effects. “If such exposure has been occurring in the past, it is important that it is ceased immediately,” he said.
Although “no resident had shown abnormal lung-function tests, some had been suffering from symptoms consistent with mined silica exposure,” he said.
A few days after the dust monitoring programme was announced, Dr Humphrey said during a Newstalk ZB radio interview with Chris Lynch that quarry dust contained fine, sharp particles of silica which were respirable and could get down into the lungs and cause serious long-term health problems like silicosis and certain types of cancers.
Silicosis was a “chronic inflammatory process,” in your lungs, Dr Humphrey said.
“It can kill you ultimately”.
However it could take 20 years to develop.
“So anybody going for a lung-function test, having been exposed to it in the short term is not likely to find any problems. But in the long term it will develop.”
ECan’s Mr Aldridge, who also took part in the radio programme, said during the interview that the dust monitoring programme was to determine the exposure levels.
“The experts tell me it will take a year to get a really conclusive view on that. But we will review it as we get results. If they are showing really high levels we will do something right away. What we have said is ‘no dust’ effectively’,” he said.
In the meantime Dr Humphrey has advised residents living near the Yaldhurst quarries to wear respiratory masks when outdoors at their homes.