Brownfield in Scotland: plenty of drivers for change
Things are on the move as far as brownfield in Scotland is concerned – with drivers including the new planning regime NP4, the Vacant and Derelict Land Commission and an environmental disaster which nearly always concentrates minds.
21 February 2020
At Environment Analyst's Brownfield Land Scotland Conference, Gordon Thomson from Lichfields said new housing targets had been included in the new planning regime NP4 stemming from the Planning (Scotland (Act 2019) and the system is more streamlined and helps the fight against climate change.
The big change is that local authorities prepare the Regional Spatial Strategies – either on their own or in partnership. The Scottish Government then prepares the Statutory Development Plans and the National Planning Framework. The local authorities and National Park Authorities prepare Local Development Plans, and new too are community bodies preparing local place plans.
Thomson asked though: Can more be done to ensure that the re-use or re-development of brownfield land is considered before new development takes place on greenfield sites? And: Are there circumstances where it would be appropriate for developers to be asked to provide evidence that development on brownfield land is not viable?
He said there are changes had already been implemented including: Masterplan Consent Areas; Meaning of Development; Pre-Application Consultation; Proposal of Application Notices; Assessment of Health Effects; Schemes of Delegation; Departures from Development Plans; Duration of Permission Conditions; Completion Notices; Declining to determine applications; and Infrastructure Levy. A significant omission is the third party right of appeal. Some of the changes have already been implemented.
But there is still time to put in ideas including in the areas of housing waste, green infrastructure, energy, town centres, climate change, flooding, transport and derelict land.
Vacant and derelict land
Alison McKay from Leapmoor said there was 11,000+ hectares of Vacant and Derelict Land in Scotland comprising 3,500 + sites. She described as a large, diverse and fragmented amount of land with huge potential with one third of Scotland’s population living within 500m of derelict site. But since figures were kept, and although some the land had been used, the amount of vacant and derelict land hasn’t changed.
Maybe that is set to change with important drivers including climate change, reducing inequalities, improving health and wellbeing and inclusive growth. Some of the sites seem ripe for housing, particularly with targets in the NP4. Some of the sites could be used for renewable energy generation – particularly as they are close to existing populations – and the drive to local and distributed energy. Others are seen as centres for green infrastructure with parks and urban greenspace while some are seen as allotment spaces. And all these could attract investment in one form or another.
Ms McKay described one such transformation in the Shettleston Growing Project established in 2018 where raised beds were brought into a derelict space and became an important and integrating focus for the local community.
An audit of the current situation revealed that the problem may not be as big as people think – but that a themed approach is required. Although there is a lack of market demand, a wide range of funding pots are available.
The Task Force aims to make better use of data to focus on problematic sites with potential; embed a joined up approach to prioritising sites in policy and funding; demonstrate effective delivery and change policy to support it; and embed a socially responsible approach to land use to stop sites becoming derelict.
Some ground-breaking reports have been produced: Assessing the Impact of Vacant and Derelict Land on Communities, from Peter Brett Associates LLP, was released in September 2019. Available qualitative and quantitative data was compiled and followed up by community workshops – with scoring criteria along the lines of health, economy, environment and community and the impact of VDL.
Ryden undertook a review of funding sources for the re-use of vacant and derelict land in October and found that some funding is available for all sizes and types of project and applicable to a wide range of applicant organisations including local authorities, charities, community organisations or business/property owners. But the sources usually don’t cover the whole project costs.
Research on the costs and benefits of VDL, is due from BIGGAR Economics, in Spring 2020. It will assess (and where possible quantify) the full benefits of bringing sites back into use and quantify the full costs of allowing dereliction to persist.
In terms of an environmental disaster - it was the incident at Gorebridge which lasted between September 2013 and September 2014. For over a century CO2 at high concentrations has been recognised as a workplace hazard particularly in mining.
During April 2014, several cases of ill health were reported to be affecting some residents in the former mining area of Gorebridge, Midlothian. Twenty two residents were hospitalized and ultimately 64 Houses demolished at a cost of £6m, several court cases resulted from the incident.
RSK's director of Geosciences Tom Henman, and managing director of RSK@Sterling Andrew Gunning explained the starting point for the RSK research, commissioned by the Scottish Government were the recommendations in the NHS Lothian IMT report which related to Scotland–wide building standards issues and by implication public health issues, which need to be addressed without delay. As such, they said, the project was more forward looking and did not consider specific liabilities around Newbyres Crescent and Gore Avenue, Gorebridge. The research project was fact-finding and included ‘options to consider’ in the final report.
RSK conducted a detailed process of literature review, stakeholder engagement, primarily with local authority staff in Scotland, and consultation with key technical experts with detailed knowledge of the issues.
The main objectives were to investigate similar past incidents in Scotland; what guidance is available on mine gas mitigation? and consideration of the eight building standards related recommendations in the Gorebridge IMT report.
Specific questions RSK were asked to consider included:
Is the current mine gas risk assessment process adequate?
Is the current risk assessment process fit for purpose particularly in terms of taking account for future potential changes?
Is there enough emphasis in the current mine gas risk assessment process on the potential for other interventions?
Are current mitigation processes sufficiently precautionary?
In determining the need for mitigation measures, is the current scope for interpretation of the guidance open to developers at present appropriate?
Would the simplest and most appropriately precautionary solution be to require mandatory gas risk mitigation measures in all new residential and similar developments in former coalfields?
Research also included looking at the scale of the problem and factors impacting gas generation and migration from old mine workings including the role of meteorological pressure and rising groundwater levels. The uncertainty of future climate scenarios adds to the drive for a more precautionary approach.
Key standards and guidance were also looked at including BS 8576:2013, BS 8485:2015+A1:2019, CIRIA C735, Local Authority Guide to Ground Gas, and CL:AIRE technical bulletins, e.g. RB17, TB17-18.
In breakout groups three issues covered: Lessons from the IMT Report and how they might influence a more precautionary approach to public health issues? Energy efficiency factors and construction techniques – are they a factor? Risk assessment processes – are they robust?
In terms of the expert consultation ten experts were selected covering: ground gas risk assessment, mitigation design, installation and verification, and air tightness.
They were asked to answer questions on: an assessment of the effectiveness and limitations of the current mine gas risk assessment and mitigation design process and identification of any possible improvements; the effect of different residential construction techniques on mine gas migration; and any suitable mitigation measures that could be implemented for existing properties found to be affected by mine gas, as opposed to demolition of the properties.
In terms of the adequacy of mine gas risk assessment process they concluded that standards and guidance based on CSM and lines of evidence approaches are robust for ground gas. Supplementary guidance would be valuable specifically to cover mine gas related issues. But longer-term changes and the impact of cumulative developments are not well covered.
On are current mitigation processes sufficiently precautionary? The experts said yes - where gas risk assessment is appropriate. But lack of enforcement and gaps in knowledge were identified as concerns.
The question on: Is the drive to improve the energy efficiency/air tightness of modern properties a potential factor contributing to the retention of mine gas emissions in a property brought a mixed answer. In newer buildings, due to improved airtightness standards, gases can enter a property are more likely to be retained, however the ingress of gas itself will also be reduced.
Would the simplest and most appropriately precautionary solution be to require mandatory gas risk mitigation measures in all new residential and similar developments in former coalfields? A range of views were expressed. Some felt that if the gas risk assessment process is followed and implemented correctly then mandatory mitigation would be unnecessary and could be counter-productive e.g. insufficiently precautionary. Others felt a minimum level of protection would address uncertainties and create a ‘level playing field’.
The recommended options for consideration by the Scottish Government were:
The use and enforcement of model planning conditions as well as changes to Scottish Planning and Building Standards and guidance to cover adequate assessment of mine gas (including worst-case conditions)
Further research and preparation of supplementary technical guidance relating to the assessment of risks to new and existing developments, specifically from mine gas
Include consideration of mine gas issues/constraints at local development planning stage, especially regarding large-scale developments and consideration of cumulative effects
Improve co-ordination and communication between planning, Building Standards and EHO/CLO staff in some local authorities and provide additional budgets for training or external specialist support where needed
Further research to assess the long-term effectiveness of granular fill and perforated pipe ventilation below slab construction as utilised in modern housing construction in areas where there is a high likelihood of mine gas emissions
Consider further the implementation of mandatory mitigation measures in former coal/oil shale mining areas
Closer liaison with Northumberland County Council to share expertise and knowledge
Validation of the experience and qualifications of those designing mine gas mitigation measures is required by developers during the procurement process to appoint consultants
The research team concluded that more robust enforcement, risk assessment and mitigation, will help to prevent further instances of ill-health in residential buildings from CO2 associated with abandoned mine workings.