LAND CONTAMINATION REPORT CRODA SITE, KILNHURST, ROTHERHAM
CONCEPTUAL MODEL AND PROPOSAL FOR SITE DEVELOPMENT
APRIL 2012
PREPARED BY: AMY LEE
Photograph by Paul Bechtold
CONTENTS INTRODUCTION
4
1. BASELINE INFORMATION 1.1 1.2 1.3 1.4 1.5
Location and Surrounding Landuses Geology and Landform History Current Site Condition Policy Context
4 4 4 8 8
2. CONCEPTUAL MODELS 2.1 Contamination Linkages 2.2 Pictorial Concept Model 2.3 Tabulated Concept Model
9 10 11
3. PROPOSALS FOR SITE DEVELOPMENT 3.1 3.2 3.3 3.4
Aims Policy Context Precedent Studies Site Devlopment Proposal Plan
SUMMARY CONCLUSIOON
LIST OF FIGURES & TABLES REFERENCES
12 12 13 14 16 16
3 17
LIST OF FIGURES Figure 1 Croda Site Location Current Ordnance Survey Plan Figure 2 Croda Site 1948 Historic Ornance Survey Plan Figure 3 Croda Site 1985 Aerial Photograph Figure 4 Source, Pathway, Receptor Linkage Figure 5 Pictorial Concept Model Figure 6 Gas Works Park, Seattle. Photo by David Van Horn 2009 Figure 7 Landscape Park, Duisburg Nord. Photo taken by TijsB 2010 Figure 8 Landscape Park, Duisburg Nord. Photo taken by TijsB 2010 Figure 9 Emscher Park, Germany. Photo by Morisius Cosmonaut 2009 Figure 10 Concept Plan Figure 11 Retained features of the site.
LIST OF TABLES Table 1 Tabulated Conceptual Model
Introduction This document looks at all the potential source, pathway and receptor linkages that may be present on the former Croda Hydrocarbons Ltd site and which need to be considered prior to development and details them in illustrated conceptual models in both pictorial and tabulated formats. An initial draft site development proposal is included for after remediation.
1. BASELINE INFORMATION 1.1 Location and Surrounding Landuses
The site is located between the towns of Kilnhurst and Swinton to the north of Rotherham and within the Dearne Valley. The River Don and the Dearne and Dove Canal run along the eastern side of the site and a railway line runs along an embankment passing the western side. The railway line divides the site from the towns of Kilnhurst and Swinton which comprise of some densely populated residential areas. There are several schools in the area including Kilnhurst Primary School and Dearne Valley College. Services close to the site include a caravan storage business to the north-west and a universal recycling facility to the south. Other than residential the other main land uses in the area include agricultural practices and recreation with many farmlands and golf courses on the outskirts of the towns. There are a number of designated woodlands and nature reserves such as Creighton Woods Nature Reserve and Piccadilly Woods to the west as well as those woodlands and wetlands associated with the River Don. The Dearne and Dove Canal is used for fishing and competitions with leisure and dog walkers also utilising the edges of the site. There is also another open body of water namely the Thrybergh Reservoir which lies to the south. See figure 1 for a current Ordnance Survey map of the site and its surrounding areas and uses, figure 2 for a 1984 historical Ordnance Survey map and figure 3 for the former site aerial photo.
1.2 Geology and Landform
The ground on site is indicated by a commissioned geology and ground condition document written by Sirius to consist of between 0.5 and 2.0m of Made Ground composed of silts, sands, gravels and demolition rubble which is thicker in the north than in the south of the site. This overlies between 1.0m and 5.0m of alluvial deposits and below this Upper Carboniferous Middle Coal Measures are present composed of layers of mudstone, siltstone, seat earth and coal in sequences up to 1500m in depth. Some of this UCMCM is exposed at the surface as weathered sandstones and mudstones. The landform is raised at the north-east due to the placement of fill materials, and the south-west area is about 6m higher than the rest of the site due to the a sandstone outcrop. The groundwater table is found in the alluvial deposit layer approximately 4.5m below ground.
1.3 History
The site was occupied by an independent tar works up until 1970 when the site became occupied by the former Croda Hydrocarbons Ltd till 1998. Croda had become one of the most notorious chemical plants in Europe in terms of dangerous contamination levels, importing 100,000 tonnes of bitumen by rail from Essex and working on a large scale to produce oils, tars and hydrocarbon polymer products for the chemical process and steel industries.
1.4 Current Site Conditions
The plant was divided into two compounds; the production plant to the north and the processing plant to the south. Most of the buildings have been demolished with some structural remnants remaining and large areas fenced off to the public. The site is vegetated by species which can tolerate the dry and damaged soil conditions and contains some habitat value and potential. There is evidence of some illegal activities and vandalism and the site is patrolled for public safety. The site is heavily contaminated by the following: -
Heavy metals including arsenic, lead and copper. Volatile Organic Compounds (VOC) including benzene, ethylbenzene and xylene. Asbestos and lime. Hydrocarbon polymers, oils and tars.
A waste disposal area/dumping lake lies on the edge of the site with an unknown concoction of different contaminants and waste. There is known to be large quantities of lime on site as well as sulphuric acid and products and by-products spilled in various locations and worry that the contaminants are breaking through the topsoil into the aquifers and water mobilising contamination buried on site. As well as the heavy contamination left behind by the history of the chemical plant there are known to be a number of underground foundations, basements, storage tanks and pipes in some areas of the site, some of which are believed to be dangerous through potential leakages and build up of VOCs which due to their location underground cannot be monitored. One of the main concerns to health is poisoning caused by lead pollution. Lead can be transported by air, soil, water and food and travel off site for long distances where it can remain in the topsoil for many years with potential to spread further. The most common pathway of lead poisoning is through the contamination of drinking water to surrounding residential areas and the health effects of exposure can be both acute and chronic, with the problems being particularly dangerous and severe for children.
1.5 Policy Context
The objectives set out in DETR Circular 02/2000, Contaminated Land and PPS23 Planning and Pollution Control promotes the identification and removal of contamination to avoid risks to human health and the environment. It encourages developments that provide an opportunity to remediate the land and create new uses which benefits the wider community. There are also several policies and guidance documents specifically dealing with contaminated land and its management. One of the most important guidance documents is the Contaminated Land Report (CLR11) written by the Environmental Agency, SEPA and DEFRA which outlines the ‘Model Procedures for the Management of Land Contamination’ to provide a framework for assessment, investigation, remediation and development of contaminated land in the UK. Since the site is in close proximity to residential areas and surface water courses there are measures which must be undertaken to prevent potential and possible harm. The site is currently designated for housing and waiting for planning permission to build around 300 houses. There is strong protest from former employees and residents due to local controversy over the health implications of the site and claims that it is not safe to build homes upon. However an application for other developments may be more welcomed such as forestry or amenity woodland if the community is well involved with the proposal from the outset.
2. CONCEPTUAL MODEL 2.1 Contamination Linkages Figure 4: Source, Pathway, Receptor Linkage.
A “contaminant” is a substance which has the potential to cause significant harm to a receptor. A “pathway” is a route by which the contaminant affects the receptor. A “receptor” is something that could be adversely affected by a contaminant. (Taken from Environmental Protection Act 1990: Part 2A Contaminated Land Statutory Guidance DEFRA). The conceptual model is used to identify potentially significant source, pathway and receptor linkages, otherwise known as contaminant linkages pre-development to inform development proposals. It is used as part of the risk assessment phase to determine if remediation measures should be taken. There is always an element of uncertainty when putting together information and so specialist help must be sought to ensure that all significant disciplines and areas are covered. The conceptual models illustrated in both pictorial (figure 5) and tabulated formats (table 1).
ATMOSPHERE AND RAIN
3. SITE DEVELOPMENT PROPOSALS 3.1 Aims
The site has the potential to form a green link from residential areas to the River Don through the restoration and revegetation of the site. The site can form a green corridor between Creighton Woods Nature Reserve and Piccadilly Woods to the west and the woodlands and wetlands associated with the River Don for migratory wildlife. Therefore the proposal for the site is to establish South Yorkshire Forest amenity woodland and community park for nature conservation and informal recreation whilst retaining as many structures as is possible to act as features and reminders of the sites history and create a truly unique place. Since parts of the site are already used for light recreation it should be reasonable to establish the rest of the site for this purpose. The site is in a strategic location and has the potential to be integrated into canal and river walk routes. This strategy aims to restore the site and change its perceptions to a place that the community is proud take ownership of and engage with as opposed to a place that they are ashamed to have.
South Yorkshire Forest Plan The South Yorkshire Forest is created and managed by the Countryside Agency and the Forestry Commission and spans across areas of Barnsley, Rotherham and Sheffield. Its objectives are to provide new habitat niches for local wildlife and benefiting the community through the creation of new landscape functions and opportunities for informal recreation as well as helping to boost investment and economical interest in the area.
3.2 Policy Context
There are several Planning Policy Statements (PPS) which are of relevance to the site proposals.
PPS9 Biodiversity and Geological Conservation PPS9 compliments the UK Biodiversity Action Plan. The main objectives are to conserve, enhance and restore the UK’s natural environment by sustaining and improving the quality and extent of green and open spaces and their habitats, processes and populations of naturally occurring species which they support, and the economical and social benefits that they promote. As part of the strategy the biodiversity and condition of the site will need to be monitored through the use of indictors such as by carrying out water and soil samples and identifying species. The site will need to be checked for protected or conservation species prior to development proposals being drafted. PPS14 Unstable Land The proposal should take into account the possibility of ground instability. Where major areas of unstable ground are unknown their general location should be made clear. There may need the judgement of a specialist to locate the known presence of underground structures on site. PPS23 Planning and Pollution Control The proposals should consider the possibility of encountering contamination during development and it is the responsibility of the developer after planning permission has been granted to remove all unacceptable risks to make the site suitable for its new use and hence not be determined as contaminated land under Part 11A of the EPA 1990.
contaminants from the soils into their tissue. This can be carried out in the initial establishment phase of planting using deep rooted species for several years before these plants are removed and the site is properly planted. Organic wastes and remediated/stabilised materials and soils can be reused on site. The site can still be fenced off until it is deemed uncontaminated and when woodland planting is reasonably established before allowing public use. There is also the option to cap the whole site prior to woodland planting. This will be an additional 1 – 2m depth of imported subsoil and layers of clay, fill, concrete, impermeable geotextile and mesh in that order above the Made Ground. This should ensure that wildlife and deep rooted species will not bring up contaminants, if still present after remediation, from soil depths. This will open up more opportunities for the types of plant chosen for the site and where they can be planted as well as remedy soil compaction.
Note on Management Management is integral to the design of this site. The site will be managed to the objectives set by South Yorkshire Forest and will be ongoing and dynamic as opposed to planted and left. There is of course always the possibility that the remediation is not entirely successful or contamination is brought back to the surface by deep rooted species and animals thus there is potential for different future receptors to be created if this proposal is to go ahead. This emphasises the need to routinely sample, monitor and assess the progress made and the conditions of the soils against set acceptable targets, i.e. as a minimum must not be determined as contaminated land under Part 11A of the EPA 1990 before, during and after development.
Summary The site is heavily contaminated and extensive surveying and risk assessments by specialists must be undertaken before development proposals and remediation techniques are implemented to break significant contaminator pathways to receptors. The main contaminants of concern are asbestos, heavy metals and VOCs located in various known and unknown areas of the site. Their remediation needs to be cost-effective and as a minimum the site must not be determined as contaminated land under Part 11A of the EPA 1990 to ensure public safety. The site has the potential to become a green link for wildlife and a light recreational space for the community and reimage itself as a place that the community is proud to take ownership of and can benefit from. The community must be involved with the design, planning and management from the outset so that the site is well managed for the long term. For the site to be a successful and sustainable green space it must be regularly monitored and assessed against strict targets for contamination and biodiversity to gain the community’s trust due to its notorious history and the local controversy surrounding it. There are many policies and documents to guide this process and precedent studies of good practice.
Conclusion The information in this document was given as specialist knowledge and documents and every attempt has been made to ensure that this information has been interpreted and analysed correctly, it should however not be seen as correct and specialist input and further surveying and assessments will need to be undertaken before design decisions are made.
References
Blacksmith Institute, 2011. The Worldâ&#x20AC;&#x2122;s Worst Toxic Pollution Problems Report 2011 [pdf] Available at: <http://www.worstpolluted.org/files/FileUpload/files/2011/WorldsWorst-Toxic-Pollution-Problems-2011-Report.pdf> [Accessed 11th April 2012]. Contaminated Land: Applications in Real Environments, 2009. Integrated Remediation, Reclamation and Greenspace Creation on Brownfield Land [pdf] Available at: <http://www.forestry.gov.uk/pdf/SUBRIM_bulletin_11.pdf/$FILE/SUBRIM_bulletin_11.pdf> [Accessed 14th April 2012]. DEFRA, 2012. Environmental Protection Act 1990: Part 2A Contaminated Land Statuary Guidance [pdf] Available at: <http://www.defra.gov.uk/publications/files/ pb13735cont-land-guidance.pdf > [Accessed 11th April 2012]. Department of the Environment, 1990. Planning Policy Guidance: Development of Unstable Land [pdf] Available at: <http://www.planningapplications.co.uk/ppg14_unstableland.pdf> [Accessed 11th April 2012]. Environment Agency, 2004. Model Procedures for the Management of Land Contamination: Contaminated Land Report 11 [pdf] Available at: <http:// publications.environment-agency.gov.uk/PDF/SCHO0804BIBR-E-E.pdf> [Accessed 11th April 2012]. Gleeson Homes and Regeneration, 2011. Former Croda Bitumen Site, Swinton Kilnhurst. Environmental Statement Part 2 Technical Paper 2: Geology and Ground Conditions. [pdf] Available at: <http://roam.rotherham.gov.uk/PlanNet/documentstore%5CGY%20AND%20GROUND%20CONDITIONS_01_1.PDF > [Accessed 12th April 2012]. Grant, A., Lange, E., Morgan, P., 2012. Course Content, LSC305 Land Contamination, Restoration and Revegetation [online via internal VLE], University of Sheffield. Available at: <https://vle.shef.ac.uk/webapps/portal/frameset.jsp?tab_tab_group_id=_2_1&url=%2Fwebapps%2Fblackboard%2Fexecute%2Flauncher%3Ftype%3DCourse%26id%3D_8530 _1%26url%3D> [Accessed 10th April 2012]. Langford, H., 2012. Guided walk around the site with talk. [site visit] (Personal communication, 16th Febuary 2012). Office of the Deputy Prime Minister, 2005. Planning Policy Statement 9: Biodiversity and Geological Conservation [pdf] Available at: <http://www.planningapplications.co.uk/pps9.pdf> [Accessed 11th April 2012]. Office of the Deputy Prime Minister, 2004. Planning Policy Statement 23: Planning and Pollution Control [pdf] Available at: <http://www.planningapplications.co.uk/pps23_planningandpollution.pdf> [Accessed 11th April 2012]. Ordinance Survey. 2012. University of Sheffield, 1:1.2500. EDINA Digimap [online] Available through: University of Sheffield Library [Accessed 13th April 2012]. South Yorkshire Forest, 2011. South Yorkshire Forest Plan 2002 [pdf] Available at: <http://www.syforest.co.uk/downloads/S_York_Forest_plan.pdf> [Accessed 12th April 2012].