Huge costs would be incurred dealing with 2 currently active landfills + 16 historical landfills for Heathrow runway
A report commissioned by Gatwick airport, in its bid to beat Heathrow in getting a new runway, says Heathrow’s north west runway plan would cost £500 million more than estimated because of the amount of potentially contaminated landfill that would have to be treated. The report by environmental consultancy RSK Group claims that Heathrow would have to launch one of the UK’s largest land clearance operations ever if it was allowed to build the runway. RSK claims the need to excavate and clear up to 9 million cubic metres of potentially hazardous landfill would increases the total cost from £18.6 billion to £19.1 billion. A report in June 2014 for Heathrow by Amec showed there are 2 current landfills and 16 historical landfills on the site, the detailed construction of which is not known. The operation to treat the landfill could not only risk releasing hazardous gases and other pollutants, but would also encourage vermin and birds – a key concern since this would take place near the existing airport. There are also risks to ground and surface water, and a Site Environmental Management Plan should be in place including details of emergency procedures to deal with incidents or unexpected contamination.
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Landfill clear-up ‘would add £500m’ to Heathrow runway cost, claims report commissioned by Gatwick
By JON REES, FINANCIAL MAIL ON SUNDAY
21.6.2015
Heathrow Airport’s plan for a third runway would cost £500million more than estimated because of the amount of potentially contaminated landfill that would have to be treated, according to a report commissioned by the airport’s rival Gatwick.
The report from environmental consultancy RSK Group was submitted to the Airports Commission – run by former Deputy Governor of the Bank of England Sir Howard Davies – which is due to announce this month which of the two airports should be allowed to expand.
The report claims that Heathrow would have to launch one of the UK’s largest land clearance operations ever if it was allowed to expand by building a third runway.
It claims the cost of excavating and clearing up to 9million cubic metres of potentially hazardous landfill would add £500million to the cost of the scheme, which the commission already reckons will cost £18.6billion.
Another scheme under consideration, called Heathrow Hub, envisages extending one of the two present runways, though this has not been proposed by the airport’s owner, Heathrow Airport Holdings, which is owned mainly by Spain’s Ferrovial and Qatar.
Any operation to treat the landfill could not only risk releasing hazardous gases and other pollutants, but would also encourage vermin and birds – a key concern since this would take place near the existing airport.
Heathrow Airport said all its proposals were fully costed: ‘Any brownfield development must meet stringent environmental standards. Heathrow’s proposals for expansion includes a detailed and privately funded remediation plan which meets the Commission’s sustainability requirements, whilst providing a once-in-a-generation opportunity to put the land to safe and productive use.’
Gatwick, owned by New York-based private equity firm Global Infrastructure Partners, wants to build a second runway in a £9.3billion scheme.
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The report by AMEC for Heathrow, on the issue of contaminated land is
“Geo-Environmental Assessment” (June 2014)
From this report, the
Non-Technical Summary
Heathrow Airport Limited (HAL) is proposing to expand the existing Heathrow Airport site to the north-west. The proposed development includes construction of a third runway, taxiways, stands, several new airport buildings,ancillary buildings and car parks. The proposed development area is large and the current land use across the area
can be summarised as:
• Industrial/ commercial estates, office buildings, agricultural land, recreational areas, car parks, hotels, an active landfill, gravel pits, residential areas, a major road (M25), petrol stations, an energy from waste plant, a British Pipeline Association (BPA) site and potentially a pipeline, a biodiversity site and surface water features; lakes and six water courses.
The ground conditions are considered to be similar across the development area in terms of solid geology with slight variations in the superficial geology. The general anticipated ground conditions comprise the following:
• Worked ground/ made ground/ Topsoil underlain by;
• Alluvium (where present), a Secondary aquifer, underlain by;
• Langley Silt Member (where present) underlain by;
• River Terrace Deposits (RTD) (where present), a Principal aquifer, underlain by;
• London Clay Formation.
As the development will be undertaken on mainly brownfield land the development will result in an improvement to high-value commercial land.
The main potential sources of contamination at the site are 2 currently active landfills and 16 historical landfills (some of which are partly within the site) which are present as a result of historical sand and gravel quarrying.
Given the number of landfills, the type of waste present and uncertainty over the landfill construction, there is a high likelihood that the Principal aquifer in the RTD, where present following quarrying, has been impacted by contaminants leaching from these landfills. There is also a possibility that surface water features have been impacted given their proximity to the landfills in some areas of the site.
In the current condition, prior to mitigation measures, there are anticipated to be low risks to current site users (those spending a considerable proportion of their time on-site, residents and workers) and low risks to off-site residents.
During the construction phase, risks to construction and maintenance workers are considered to be low based on the assumption that, as is standard practice, the workers will be wearing suitable Personal Protective Equipment (PPE), adopt best-practice site hygiene procedures and comply with site health, safety and environmental management plans.
There is the potential for spills and leaks from equipment and storage areas during the construction and operation phase of the development. In order to ensure low risks from spills and leaks to environmental receptors, including ground and surface water, a Site Environmental Management Plan should be in place including details of emergency procedures to deal with incidents or unexpected contamination.
During the operational phase it is assumed that mitigation measures will have been included in the construction process to reduce risks to human health and environmental receptors. Risks may include presence of ground gas, contaminated soils and groundwater and the potential creation of preferential pathways during construction works.
Outline recommendations for mitigation measures have been included in Section 5 of this report. These recommendations should be reviewed following completion of finalised development proposals, confirmation of foundation design, location of landscaped areas, river diversions and flood storage areas.