Gasworks site original use
The site was used for gas production and storage from 1818. Gas production stopped in 1860 but the site continued to be used for gas storage in up to seven large gas holders over the entire site.
From 2012, gas was stored in underground mains. The gasholders are no longer in use, though two remain on site. A small part of the site remains in use for gas infrastructure and would be retained if the site is developed.
Potential for contamination
Former industrial sites can contain harmful substances such as:
- oils and tars
- waste metals
- organic compounds and gases
These can be leftover from or created by the previous activities on site.
Land is affected when there are polluting substances in, on or under the land. This may mean that there are substances left in buildings or on land, or that the substances are buried in the ground. These can harm human health or cause water pollution.
Because the site was used for the production and then storage of gas, it could be contaminated.
The applicant’s Environmental Impact Assessment (EIA) Scoping Report states that the developers did an initial assessment for the owner of the site prior to submitting their planning application. You can find more information on contaminated land and the planning process on gov.uk.
About Environmental Impact Assessments (EIA)
Environmental Impact Assessments (EIA) form part of the planning application process. We use them to test developments which could have ‘significant effects’ on the environment.
The aim of the EIA is to protect the environment. It does this by ensuring that when making decisions on planning applications, planning authorities like us have full knowledge of the likely significant environmental effects.
It's a formal procedure which the applicant must do to first agree with us whether the project should be subject to an EIA (the EIA screening process). If it does, then the applicant should then seek our agreement as to which environmental effects to assess and how (the EIA scoping process). An EIA is then carried out and the results submitted with the planning application in an Environmental Statement.
You can learn more about EIAs on gov.uk.
EIAs and the Gasworks site
As part of the planning application to redevelop the Gasworks site, the developer has to submit information showing how the site can be cleaned up safely. This will include:
- investigating what contamination is on the site and where
- quantifying existing and future risks
- demonstrating how developers will prevent it from harming people or the environment.
Some initial work is already complete. This includes:
- a desktop review of historic uses
- borehole data
- groundwater sampling
The Gasworks scheme is an ‘EIA development’ because it has the potential for significant environmental effects (within the meaning of the EIA Regulations). The scope of information to be submitted as part of the EIA was agreed through a Scoping Opinion issued by the Council on 19 November 2020.
The applicants planning application will need to identify what the risks are of contaminants reaching people and the environment, and crucially, how this risk would be mitigated during any redevelopment.
It is the applicant’s responsibility to show that the development can come forward safely and address issues of contamination and environmental impact.
'Special site' status
A ‘special site’ is a site identified under the Contaminated Land Regulations 2006,. The effect of this is that the Environment Agency becomes the enforcing authority. They are then responsible for environmental clean-up.
The Gasworks site has not been identified as a ‘special site’.
Risks of contaminated sites to human health and the environment
The risk of contamination depends on the site conditions and nature of the contamination. It can also depend on any ‘linkages’ between the contamination (the ‘source’) and people/the environment.
For there to be harm to human health, there needs to be a source of contamination at a concentration that could cause harm. There have to be people present, and there needs to be a pathway of exposure (breathing in dust/gas, drinking contaminated water etc.).
A site may therefore be contaminated, but if there are no ‘pathways’, there will be no risk to human health.
A contaminated site can harm habitat and species if there is a source of contamination at a concentration enough to cause harm and where there is a pathway of exposure. This could include examples such as wildlife consuming contaminated plants or water.
Ensuring that the Gasworks development is safe
The applicant has to set out in the planning application how the development can come forward without putting human health at risk from any contamination on the site. They have to consider risks, both during the redevelopment and following completion of construction.
They will assess the level and type of contamination on the site now, the increased risks of dispersal the development may create, and how they will prevent this.
How our planners will know if the measures the applicants propose will work
Planning officers will consult with a range of specialists, including:
- the council’s Environmental Health specialists
- an externally appointed Contaminated Land specialist
- the Environment Agency
- Public Health England
- the council’s Director of Public Health
These experts will assess the information in the planning application and provide comments on it, including whether they agree the developer’s approach is safe.