Callaghan sought help with deadly gas
Callaghan Innovation last year sought help from the New Zealand Defence Force to deal with the storage of potentially lethal hydrogen sulphide gas at its site in Lower Hutt.
According to partially redacted communications released under the Official Information Act, Callaghan sought the intervention of then Defence Minister Andrew Little.
The institute had been seeking a solution since October 2022. In a February 17, 2023 letter from then Callaghan chair Pete Hodgson to Little, Hodgson asked for help from the Explosive Ordnance Disposal (EOD) squadron “in the packaging of one of three cylinders of hydrogen sulphide (H2S) gas”.
“This request is highly unusual, as indeed is the need,” Hodgson wrote.
The packaging would be in the form of a cylinder overpack Hodgson understood was held by the EOD.
The EOD was established as part of New Zealand’s response to domestic explosive disposal incidents and provides chemical, biological, radiological and explosive capability.
Callaghan wanted outside help because although it had arranged for its own overpack to be manufactured, its delivery was between four to six months away, if not more.
Although the EOD had advised that its remit was to respond only to emergencies, Hodgson asked Little to step outside that remit on this occasion.
Hodgson wrote to Little again on May 3 after not getting a reply to his earlier letter. He stated that Callaghan expected to receive the cylinder overpack it had ordered by midJuly or soon after that.
“Assuming we are then able to dispose of the H2S gas, we would be open to others using such an overpack [rest of sentence redacted].”
Little replied on May 12, declining the request. He stated that the EOD didn’t have a suitable pack available but had been helping Callaghan Innovation have its own one built.
He noted that Callaghan had wanted the Defence Force’s (NZDF) support
“to deal with a hazardous substance in the care of Callaghan Innovation at a Wellington site”.
Callaghan’s main facility is located at Gracefield in Lower Hutt.
Little’s letter stated that a multiagency team had carried out an inspection of Callaghan’s site on December 14, 2022. The team included WorkSafe, the EOD, Defence Technology Agency, and Fire and Emergency NZ (Fenz).
“The outline findings indicated that the nature of the risk and the remedy does not constitute an emergency immediate response task for
NZDF, EOS or Fenz and it does not preclude the use of commercial and industrial options which are currently available through vendors within NZ,” Little wrote.
A full report was being prepared by WorkSafe.
Callaghan has now decided to neutralise the gas on-site in the coming weeks.
Callaghan Innovation stated the gas was bought in 2002 by Callaghan Innovation’s predecessor at the Gracefield site, the former crown research institute (CRI) Industrial Research Limited (IRL).
It was used to investigate resistance to corrosion in materials used for geothermal energy production. Last month RNZ reported, based on leaked documents, that hazardous goods storage was “not up to scratch” in some of its laboratories. Hydrogen sulphide is a heavier-than-air gas that is produced in several industrial processes and is often present in oil and gas wells.
It smells of rotten eggs at low concentrations.
However, at 100 parts per million (ppm), the gas quickly overpowers the sense of smell. It is highly combustible and explosive. According to the United States Occupational Safety and Health Administration (OSHA), death can occur after 48 hours at 100ppm. Above 500 ppm, a person will collapse in five minutes with death after 30 to 60 minutes. Death is nearly instant at higher concentrations.
In the event of a leak of H2S gas at its Gracefield site, Callaghan staff would be the ones most at risk.
The nearest residential houses are several hundred metres away on the other side of the Waiwhetu Stream.
Surplus to requirements
Callaghan Innovation chief executive Stef Korn said in a statement one of the three gas cylinders that the H2S was stored in was showing signs of ageing.
They had been deemed surplus to requirements in a site-wide audit of hazardous substances in 2017.
“Since the hazardous substances audit, we have been pursuing a number of avenues for the safe removal and disposal of the gas from our site, but we have not been able to find an appropriate solution outside of Callaghan Innovation.”
The cylinders were stored in a dedicated bunker with a comprehensive system in place to monitor for abnormal levels of the gas.
Korn said a plan had been developed by Callaghan in consultation with Fenz and the Hutt City Council, along with WorkSafe and an independent consultancy, to safely neutralise the gas on-site.
This was expected to be carried out on site in the next few weeks.
Korn said he was confident that Callaghan’s health and safety systems, processes and people would ensure its staff would be kept safe while the H2S gas remained on site and during the neutralisation process.