All you need to know about contaminated land surveys in Manchester
Potentially hazardous substances have been left in the ground by the textile and dye works, heavy engineering, chemical, gas and brickworks that were built in the city during the Industrial Revolution. Manchester was a hub for the textile industry, specifically cotton, alongside manufacturing machinery and engineering. Pollutants include heavy metals such as lead and mercury which can contaminate soil and water, asbestos, radioactive contamination and volatile organic compounds released by solvents.
Anyone aiming to redevelop sites that may be affected by contamination must be aware of the steps they need to take, which include investigation and remediation to satisfy planning authorities.
Manchester City Council: contaminated land and the planning process
Brownfield redevelopment is a key part of the city’s development strategy. Redeveloping land affected by contamination comes with environmental risks and an enforcing authority will require evidence that the correct assessment procedure has been carried out. The relevant risk assessments must be conducted to ensure the safety of future site users.
Manchester City Council’s Contaminated Land Strategy identifies contaminated land and those responsible for improving it. Its contaminated land regime aims to make contaminated sites safe and keep a public register of remediated land.
Contaminated land: the legal framework
The Environmental Protection Act 1990 governs the management of contaminated land in England and Wales. It requires local authorities to identify and inspect potentially contaminated sites, assess whether a site presents risk of significant harm and ensure that appropriate remediation measures are taken.
Based on risk levels, land is placed into four categories, from category 1 being high risk requiring immediate action, to category 4, presenting no risk or an acceptable level of risk.
Land contamination and planning policy
The presence of contaminated substances is a material planning consideration where land may be affected by contamination. Contaminated land is defined in section 78A part ii a of the Environmental Protection Act 1990, as land that due to substances in, on or under it, may lead to the possibility of harm being caused. The principles apply also to areas where there is significant pollution of controlled waters or significant risk of such.
The responsibility for ensuring that development on contaminated land is safe rests with the developer, landowner, or both, according to Paragraph 197 of the National Planning Policy Framework (NPPF). Central to the NPPF is a presumption in favour of sustainable development, which states that planning policies and decisions should support the use of suitable brownfield land for development. Reusing brownfield sites aligns with the aims of reducing urban sprawl and preserving greenfield land.
Why is land contamination a planning issue?
Disturbing land that may be affected by contamination creates risk from exposing the pollutants. New pathways may be created to allow the contamination to spread and potentially affect new receptors such as people or watercourses.
Risk from contamination depends on:
- The source of pollutants.
- A pathway: a means for the contaminants to reach receptors, e.g. via inhalation or skin contact.
- A receptor: ecosystems or people that may be exposed to the pollutants.
Risk is reduced if one of these three elements is missing, i.e., contaminated land that’s inaccessible to the public creates a minimal threat.
Land Contamination Risk Assessment (LCRA)
While an important element of a planning application, a LCRA will rarely prevent a development from proceeding. However, failing to address contamination issues correctly could harm human health and/or the environment. A LCRA will comply with statutory guidance by showing that the contamination issue has been investigated, the plans will not create unacceptable risk and remediation work is viable.
The Environment Agency’s Land contamination risk management (LCRM) – GOV.UK guidelines lay out the stages for assessing contamination risks.
The process:
Phase I
This involves desk studies to investigate historic land use and identify potential sources of contamination and risk to current users and future receptors.
Phase 2
A site visit and ground investigations will take place, involving sampling and testing to identify the original source of any contaminants found, their risks and optimal remediation methods. This will be followed by remediation: a design strategy to clean up the site and mitigate risks from it. Remediation methods include:
- Excavation and removal of contaminated soil and replacement with clean soil.
- Soil treatment: pollutants are neutralised using chemical or physical or biological methods.
- Capping: a barrier is laid over the contaminated area such as concrete or clean soil.
- Groundwater treatment: on-site treatment of contaminated water or extraction for off-site treatment.
- Validation reporting: this will confirm that remediation has been carried out successfully to make the site safe. Additional information includes results of soil treating and analysis and a material management plan to show how materials will be handled during remediation works.
Submitting a contaminated land assessment by a competent geo-environmental consultant, should:
- Help the LPA to process an application efficiently and add appropriate conditions.
- Lessen chances of objections to a scheme.
- Reduce delays arising from environmental searches during a property sale.
- Minimise risk of future liabilities concerning the site.
- Protect the health of future site users.
Risks and opportunities
Contaminated land presents opportunities for regeneration schemes in city centres such as Manchester. By following statutory guidance, investigating risks on contaminated land and carrying out remediation correctly, planning applications can proceed through the planning system. The result can be the sustainable reuse of land to create new housing and viable communities.