Wynyard Point bioremediation works

01 February 2023 - 31 July 2023

Wynyard Quarter
Complete

The past, present and future of Wynyard Point...

Wynyard Point is an area that will be one of the most important regeneration projects in the city over the next 10-20 years.

Plans to regenerate Wynyard Point

Once an area underwater, Wynyard Point was reclaimed using fill material from a former gasworks site. The area had more recently been known as the ‘tank farm’ due to the range of tanks previously used to store petrol and liquid chemicals before they were transferred off site. The lease on the various sites were due to expire between 2022-2024, however, in advance of the 36th America’s Cup event, negotiations enabled the businesses to relocate elsewhere earlier than anticipated.

Work is currently underway to regenerate Wynyard Point into a major urban park surrounded by mixed use development. This is based on the work planned by the legacy urban regeneration agencies since 2005 and is now becoming a reality through the redevelopment lead by the Auckland Urban Development Office, on behalf of Auckland Council.

However, before any development could take place, the lessee of the site (Shell Ltd) was required to remediate the area from the previous uses on the site.

These works were carried out by a process called bioremediation and were:

managed and completed by Shell, in accordance with the approved resource consent conditions,
monitored by Shell and by Auckland Council Regulatory Services.

Contact details

Monitoring queries and complaints: Auckland Council Regulatory Services 09 301 0101

General enquiries

Monitoring queries and complaints

Site contamination

The northern end of Wynyard Point was formerly the Shell Wynyard Wharf facility. This site once homed 53 storage tanks and because of that the land was exposed to materials during the fuel handling processes.

Thorough site investigations were carried out by Tonkin and Taylor in 2020 and by ERM in 2021 to understand what contaminants are present and where. This work included soil and groundwater sampling and testing across the site via bores and excavations.

The findings of contamination were generally located in the upper one metre of soil and correlated with historical petroleum and chemical storage (hydrocarbons) and reclamation fill sourced from the gasworks site.

How does the bioremediation process work?

Site bioremediation was carried out by contractors appointed by Shell Ltd, in accordance with the resource consent that was granted by Auckland Council in August 2022.

As part of the process, excavated contaminated soil was sifted, turned and placed in large piles with pipes inserted inside to pump air and amendments in. This active process speeds-up the natural process of breaking down the contaminants (as shown in the image below). The soil is monitored to track progress. Once the soil is remediated to the required standard it is then spread back throughout the site.

This is the most sustainable method, as it minimises the need for vehicle transport for off-site disposal of impacted soil (except for a small amount of some material needing to be disposed of offsite), and the need to then import a bulk amount of new soil/fill in to replace it.

The bioremediation was completed in a targeted approach so that there was less disturbance and less risk to the immediate environment. The methodology had the support of technical experts in this specialist field.

The works were monitored by Shell and by Auckland Council Regulatory Services. Now that the works and subsequent monitoring has been completed, Shell Ltd.’s obligation of returning the land so that is suitable for future public use has been fulfilled.