Oceans-ESU - Site Development for Sainsbury's Millennium Store, Greenwich

Job title: Sainsbury's Millennium Store
Industry: Retail development
Clients : Sainsbury's Supermarkets
Sites: Beside the River Thames, Greenwich, London, England

Oceans-ESU were appointed by Sainsbury's Supermarkets as environmental consultants for the development of their new Greenwich site. The Millennium Store project offers a good example of how we can work effectively to provide solutions and support from the earliest stages of a project.

The project included:-

Special project characteristics
The high profile project had a number of special characteristics:-

Oceans-ESU developed a comprehensive environmental management solution for the site, which included:-

This revealed that the area was previously used as a sports field and had been in close proximity to gas works, fuel research sites and other heavy industry, so a degree of ground contamination could be expected.
The site had previously been remediated as part of a wider project, so that over 17,000 m³ of typical gas works contaminated materials were removed from the site. These works were overseen and approved by the Environment Agency to render the site safe for its intended use as a retail development.

Since the planned works required re-contouring (and bearing in mind the previous nature of contamination) a site survey was required. This revealed some areas where traces of contamination associated with the gas works could still be found.

A separate aspect of the environmental assessment identified the potential for ground gas (methane) within the region. This was confirmed by results obtained from a number of installed bore-holes, due to the site being situated on top of the old Greenwich marshes.

The short timescales and high profile of the project led to a recommendation to protect the building from the methane using a gas proof membrane and vent layer - designed to dilute any gas underneath to under 1% volume. This was fixed to the outside of the building to prevent methane build-up underneath the structure and to minimize any associated risk to the public. Due to the complex nature of the floor slab and the combined heat and power under-floor heating, the methane protection layer was specially designed - and may well be the first of its kind.

The methane defenses work hand-in-hand with an in-store detection system and external system, which is remotely monitored via modem at Oceans-ESU head offices.
Any changes or fluctuations in methane levels in or below the store set off alarms on a computer system so that an investigation can be launched immediately and act before the gas builds up to dangerous levels.

As part of the ongoing contract between Oceans-ESU and Sainsbury's, Oceans-ESU will be monitoring the methane levels within the store, providing emergency call-out support, should any methane be detected.

Specialists in reed bed technology, Oceans-ESU have applied their solutions worldwide to solve effluent treatment problems in domestic and industrial situations.

It was decided to create a natural wetland garden area, utilizing the rainfall from the roof for irrigation. The rain falling on the roof picks up pollutants, so the first stage of the design was to flow the water through a reed bed, where the pollutants are filtered out and treated.
This leaves a purified rainwater stream that flows into the lagoon area.
Around the edges of the lagoon emergent plants are placed. The plants and lagoon areas provide habitat for aquatic wildlife, as well as a pleasant and interesting landscape feature.The provision of this wetland area also reflects the previous wetland habitat that naturally occurred in the area.

The Millennium Store project offers a good example of how we can work effectively to provide solutions and support from the earliest stages of a project.