Gas Environmental Programme

Powerco says a challenging pipeline refurbishment the firm completed in Tawa earlier this year is an example of the results its international best practice environmental management system is delivering.

The main gas pipeline into Wellington crosses the Porirua Stream in Tawa where it is suspended under a road bridge and about 400 mm above KiwiRail’s electrified lines.

Powerco’s Takapu Aerial Crossing Refurbishment project involved inspecting the approximately 45-year-old pipe to assess whether it needed to be repaired or replaced.

Powerco says the complex and potentially hazardous work had to be carried out safely while also minimising any potential pollution to the stream and the surrounding environment. Any major incident, such as an uncontrolled gas release, could have caused serious harm to workers, cut gas supplies into Wellington during Christmas, and damaged or shut the North Island main trunk rail line.

Contractor NSB Protective Coatings carried out the work which involved removing the pipe’s steel casing and its yellow protective coating, repainting the 45-metre length of pipe and refurbishing its steel casing and brackets.

Powerco says the work was carried out within an all-encompassing wrapping within the scaffolding erected for the job. That screening enclosed all debris from the work and ensured that all contaminants were safely removed to a landfill.

The work was completed in January and a review showed that all consent conditions were met and that NSB had complied with Powerco’s environmental management system. The review also provided recommendations on how to conduct similar projects in the future.

Powerco has employed an environmental advisor within its health safety environment and quality team for the past seven years.

It is also the only gas pipeline operator in New Zealand to have gained certification for its environmental practices through membership of the independent Enviro-Mark programme. It has achieved the Gold standard and aim is to achieve Enviro-Mark’s Diamond standard – the highest possible level – by June 2016.

Powerco says the environmental management system aims to develop work practices and culture that minimise risks to the environment.

Examples of other initiatives undertaken include the under-grounding of four of the company’s district regulator stations (DRS) in order to improve the visual environment and reduce noise pollution.  Another eight stations are being considered for undergrounding.

Powerco has also employed young artists from the Wellington City Mission to paint above-ground DRS buildings.

The company’s Gas Hub arm was spending up to $400 a month cleaning up graffiti on the bare concrete structures. This artwork has created attractive public amenities which also double as an advertisement for the gas network.

Powerco says its focus on sustainable practice now runs through wide range of the company’s activities.

On the network it is building up a large amount of data on the environmental performance of its equipment, at a range of locations; across the company it is aiming to halve its waste per person by the end of next year.

The Environmental Initiative of the Year award category is sponsored by Transfield Worley Power Services