Developing Contaminated Land Within Stirling A guide to developing land which may be contaminated Introduction Part IIA of the Environmental Protection Act 1990 (Part IIA) came into force on the 1 April 2000. It introduced a new regime specifically to address the legacy of contaminated land, including its identification and remediation. In broad terms, it applies where land is causing unacceptable risks to people or the environment. This is assessed on the basis of the current use and circumstances of the land. It is the Council’s duty to ensure that owners and developers of potentially or known contaminated sites in its area carry out the necessary investigations and put forward proposals for dealing with any contamination in a responsible and effective manner. Examples of potentially contaminative uses of land are attached in Appendix A. Planning Applications and Contaminated Land Land contamination is also a material consideration for the purpose of town and country planning. Before granting Planning permission, the Council as Local Planning Authority will ensure that full account is taken of the condition of the land concerned and that appropriate remediation is carried out to deal with unacceptable risks. It is the Government’s intention that any land that has been developed through the planning process should not be able to meet the definition of contaminated land under the terms of Part IIA. When a development is proposed, it is necessary to consider the risks from any contamination present on the basis of the new use/ development and circumstances of the land. In Stirling, planning applications which are considered for potential land contamination issues are screened against the Council’s Contaminated Land Database. Where a development is proposed on land which appears to the Council to be potentially contaminated it will inform the developer of this at the earliest opportunity. It is however the responsibility of the developer to ensure that contaminated land issues are appropriately considered, that remediation takes place if necessary, and that the land is safe and “suitable for use” (ie cleaned up to a level that is appropriate for the proposed end use). For example a commercial site surrounded by hardstanding may not require to be cleaned up to the same standard as a site proposed for domestic gardens. Where a potential source of contamination is identified, a Phase I investigation (Desk Study) will be required of the applicant (See Site Investigation Guidance which follows). Once your Phase I investigation is complete, it will be audited by a Contaminated Land Officer, who will advise if supplementary information is required. Should the Phase I investigation show a negligible risk of ground contamination, no further action will be necessary. However, if a risk is identified, a Phase II investigation (sampling & analysis) may be required, followed by remediation and validation as necessary (See Site Investigation Guidance which follows). (It should be noted that in some cases, remediation activities themselves may constitute ‘development’ within the meaning given within Section 26 of the Town and Country Planning (Scotland) Act 1997, and therefore require planning permission). Where contamination has occurred or is suspected, the Council will expect a suitable site investigation to be carried out. Building Control Warrant Applications and Contaminated Land Where development works are not subject to the requirements of the Planning Regime, the Building Standards (Scotland) Regulations 2005, made under the Building (Scotland) Act 2003, provide powers to require measures to be taken to protect the fabric of new buildings, and their future occupants, from the effects of contamination. Regulation 16(1) states that sites and ground immediately joining sites shall be prepared or treated in order to provide protection from harmful or dangerous substances. In Stirling, all building warrant applications which do not have associated planning applications are addressed for contaminated land issues. However, where developments are subject to planning and building warrant applications, contaminated land issues will normally be addressed through the planning process. When screening building warrant applications for potential land contamination issues, the site is screened against the Council’s Contaminated Land Database. Where a potential source of contamination is identified, a Phase I investigation (Desk Study) will be required of the applicant. Once your Phase I investigation is complete, it will be audited by a Contaminated Land Officer, who will advise you if supplementary information is required. Should the Phase I investigation show a negligible risk of ground contamination, no further action will be necessary. However, if a risk is identified, a Phase II investigation (sampling & analysis) may be required. The purpose of this type of investigation is to identify the nature and extent of any contamination in order that a risk assessment may be carried out. (See Site Investigation Guidance which follows). Where contamination has occurred or is suspected, the Council will expect a suitable site investigation to be carried out. Site Investigation Guidance A contaminated land site investigation is a phased approach to determining whether a significant risk exists from the type and extent of any contamination in, on or under a site. (Every site will not necessarily require each Phase to be carried out). It involves characterising your site on a conceptual model which is updated as you carry out research (Phase I), sampling and analysis (Phase II). Where contamination is identified, a risk assessment requires to be carried out to determine whether the contamination is likely to have an impact on human health, controlled waters or the environment. Conceptual Model A Conceptual Model is a representation of the site and surrounding area. It is a simplified description of the environmental conditions and its purpose is to identify potential sources of contamination, receptors which may be affected by contamination (for example, humans, water courses, the environment) and pathways which may link the two (for example the food chain, drinking water supply, inhalation of dust). A Conceptual Model is usually a mixture of pictures, diagrams and text and it is used to provide a vision of the site. It is important that your conceptual model is updated regularly during your site investigation. Phase I (Desk Study) A Phase I investigation is the research which should always be carried out before any sampling or analysis is undertaken. Its purpose is to identify whether the site has been subject to contaminative uses as well as considering potential receptors and pathways. Examples of the information which should be looked at when carrying out a Phase I investigation includes the following: Site history – previous and current uses of the site and neighbouring land. Geology, hydrology and hydrogeology. Local Authority and SEPA Records including current and historic licences and consents. Site Walkover. Etc. Once gathered, this information can be used to aid the design of the Phase II investigation. A checklist against which the contents of Phase I investigations will be assessed is attached in Appendix B. For further information on Phase 1 investigations see more detailed Phase I investigation Section overleaf. Phase II (Intrusive Investigation) There are three types of Phase II Investigation - Exploratory, Main and Supplementary. An Exploratory Investigation may be used to obtain an indication that your Conceptual Model is generally correct before carrying out a Main Investigation. This is likely to involve limited sampling and analysis of one or more of the following: soil, surface water, ground water and soil gas. An Exploratory Investigation can be used to confirm information suggested by the Conceptual Model for example, location of underground tanks. Non intrusive techniques, for example for locating below ground structures may also be employed during the Exploratory Investigation to provide further information to aid the Main Investigation The Main Investigation will involve more extensive collection and analysis of soil, water and gas samples. Its purpose is to obtain all the necessary information for the assessment of human and environmental risks. It should enable a full assessment of risks to be carried out along with the design of remediation works and quantification of costs. A review of the outcome of the Main Investigation may identify aspects where there is a deficiency in information. In this case a Supplementary Investigation may be carried out for example, to improve the accuracy of costs of remediation work. A Supplementary Investigation will be designed to produce quite specific information. A checklist against which the contents of Phase II investigations will be assessed is attached in Appendix B. For more detailed information on Phase II investigations see overleaf. Phase III (Remediation Strategy/Validation Report) Remediation is the action taken to decontaminate a site or reduce the contamination to an acceptable level. Examples of types of remediation are as follows: Removal of contaminated soil to an appropriate landfill site with any void created replaced, if necessary, with uncontaminated soil. Containment of contamination, for example, lining and capping of the site. Treatment by chemical, physical or biological processes to destroy, remove or make safe contaminants. A Remediation Statement will require to be submitted for approval before any works commence. It is a document detailing the objectives, methodology and procedures of the proposed remediation works. Following remediation a Validation Report must be submitted, demonstrating that the remedial actions have been carried out satisfactorily and remediation targets achieved. Ongoing monitoring of sites containing contamination or of those which have been remediated may also be necessary. Omitting any significant part of the above process is likely to considerably delay the Planning/Building Control Process. For further information/advice please contact Stirling Council Environmental Health Section (Contaminated Land) on 01786 432193/2247. Use of Consultants Depending on the type/extent of the contamination and the nature of the site being investigated, the specialist methods/materials required for site investigation may require the use of Consultants/Specialist analytical laboratories. Care should be taken in appointing such persons to ensure they have the necessary skills/experience to carry out the work to the required standards and that they carry the necessary indemnity insurance. Stirling Council will not recommend individual consultants or companies. Useful References Appendix C contains some references which should be of use in providing information on Site Investigations. Detailed Site Investigation Guidance Phase I Reports Preliminary Investigation A comprehensive preliminary investigation should always be carried out before any systematic sampling or analysis is undertaken. Its principal aim is to obtain information in order to: Evaluate the likelihood of finding contamination, its nature and its extent. Evaluate the environmental setting of the site and to identify sensitive receptors. Provide information from which likely contaminant-pathway-receptor linkages can be identified; Determine the requirements for further investigation (if any); Identify any special procedures and precautions that will be necessary during subsequent sampling and examination of the site. The following two steps are the basis of the preliminary investigation. 1 Data collection, which again is in two parts. a) Desk study, which should cover the following topics: The history of the site and adjoining areas. Particular attention should be paid to the nature of any industrial process or other activities on the site that could have been potentially contaminative or could have modified the ground structure to create migration pathways; Any previous desk study or site investigation; The geological, geochemical, hydrogeological, hydrological, archaeological and ecological setting of the site; Potential receptors of contamination (for example, current and intended users, trespassers, surface waters, groundwaters, nearby water abstractions, property); The proximity of any licensed or unlicensed waste disposal sites or other sources of contamination, including hazardous gases, that could have an impact on the site; The existence of naturally occurring harmful materials such as radon or naturally enhanced concentrations of harmful substances; The presence of any mining activities; Any constraints on an intrusive site investigation (access or height limitations, underground services or obstructions, noise, working hours etc). Information pertaining to the desk study would include, for example, historic maps, aerial photographs, documentary records held by current/former landowners, interviews with local residents etc. The Local Authority may be able to provide information on previous site remediation, historic environmental nuisances, conditions of planning consents, closed landfill sites and private water abstractions. The Scottish Environment Protection Agency (SEPA) may be able provide information on groundwater and surface water quality, pollution incidents, Integrated Pollution Control (IPC) and Integrated Pollution Prevention and Control (IPPC) authorisations, groundwater abstraction licences, operational and closed landfill/waste treatment sites and “special sites”. Other organisations who may provide useful information would include British Geological Survey, Health and Safety Executive, Fire Authorities, Water Authorities, Petroleum Officer, Coal Authority, National Radiological Protection Board, Local Community Councils and Heritage Associations. b) Site Reconnaissance. A visit should be made to the site, neighbouring land and the local area, with the purpose of: Validating the information collected during the desk study; Collecting additional information about the site, its environs, and any potential contaminants, pathways and receptors; Record observations of aspects of the site not revealed by the desk study; Assist in the planning of any subsequent phases of field investigation (taking into account any constraints to assess). Where possible, the site visit should be in the company of someone familiar with the site and photographs of salient features should be taken where possible. A reconnaissance visit may not always be necessary, for example where the site is fully developed and useful information will not be derived. In some cases, clients may not require site visits. In such cases, the agreed specification for the preliminary investigation should clearly state that a reconnaissance visit is not included in the work to be carried out. 2 Interpretation and Reporting The information from the desk study and reconnaissance visit should be collated and evaluated to formulate an initial conceptual model, which should identify: Potential types and depths of contaminants; The likely vertical and horizontal stratification of natural and manmade layers beneath the site; Strata variability (occurrence and thickness) in different areas of the site, and their relevant permeability, both vertically and horizontally; Potential migration routes (including airborne dispersions); The presence of service trenches, drainage runs, underground storage tanks, former foundations, and any other physical features which might influence the occurrence or migration of contamination; The occurrence of any biological, chemical or physical processes that might affect contaminant concentrations and migration (including natural attenuation); The characteristics of groundwater bodies beneath the site, groundwater levels and flow directions; The presence of surface water bodies on, or adjacent to the site; Other potential receptors. The conceptual model should be refined following further investigations. Where the existence of adequate site investigation information has been revealed by the preliminary investigation, a quantitative, or semi-quantitative, risk assessment can be undertaken. The risk assessment should include the following aspects: Identification of contaminants, pathways and receptors; Estimation of the likelihood, nature and extent of exposure to a hazard; and the risk of adverse effects; Assessment of the likely pollutant linkages and the degree of risk; Evaluation of the need for controlling the estimated risk. The findings of the preliminary investigation should form the basis upon which the requirement for, scope of, and phasing of, subsequent investigations are decided. It should be completed by the issue of a report including presentation of the conceptual model. Phase II Reports Exploratory Investigation This may involve the collection and analysis of soil, surface water, groundwater and soil gas samples dependent on the information required appropriate to the objectives. An exploratory investigation may be used to obtain an indication that the initial conceptual model is generally correct before carrying out a main investigation to provide detailed confirmation. Where the conceptual model identifies the likelihood of localised contamination and the direction of groundwater flow is a “guestimate” an appropriate strategy would be to carry out an intrusive exploratory investigation to provide information on the actual presence of contaminants and groundwater flow and quality. Hence, targeted sampling is normally undertaken. Alternatively non-intrusive investigation techniques may be employed to locate below ground structures or other features of the site prior to intrusive examination as part of the main investigation. It may become apparent following the exploratory investigation that, for example, the contamination is greater or more complex than anticipated. In such cases, the information obtained is likely to be inadequate to make decisions with the necessary degree of confidence, and it will be necessary to review the initial conceptual model and the requirements of the risk assessment. Further investigations may be required to refine the conceptual model and provide robust information for the risk assessment. The review of the exploratory investigation may allow a decision to be made that no further investigation is required, or, alternatively, the information may be used to design the main investigation. The sampling strategy for the exploratory investigation should identify the following: The objectives of the investigation and the possibility of zoning the site; The location, pattern and number of sampling points; The depths from which samples should be collected, the samples to be collected and any monitoring requirements; The methodology by which samples should be collected, stored and preserved, taking into account any off-site analysis to be undertaken; Any safety measures needed to protect personnel or the environment. The following should be taken into account; The potential heterogeneity of distribution of contaminants; Ensuring the sample submitted to the laboratory is representative of the location and depth from which it was taken; Although water bodies tend to be more homogeneous in composition than soil, stratification can still occur in groundwater and surface waters; Soil gas samples can be representative of a large zone, however the ability of soil gases to migrate in all directions should be borne in mind; The possibility of creating routes for migration during sampling. Either targeted or non-targeted soil sampling may be carried out dependent on the conceptual model. Exploratory investigations can place greater emphasis on the confirmation of suspected sources of contamination by targeted sampling, with limited non-targeted sampling to allow consideration of general areas of the site. When sampling groundwater, information on groundwater flow will help decide the best locations and depths for monitoring wells. A phased approach can then be implemented in which flow patterns are first established and then further monitoring wells installed where they are considered most likely to produce useful information. Where there is no clearly defined source, groundwater monitoring wells should be installed on a non-targeted basis. However, where a potential source is known, monitoring wells should initially be installed directly underneath. Where there is possibility of soil gas contamination, it is necessary to determine its composition and migration potential. Again, monitoring well locations should be determined based on the conceptual model and may be targeted or non-targeted. Subsequent monitoring wells can then be positioned on the basis of the information from the initial installations. The direction of possible migration both vertically and laterally, should be given consideration, and spacing determined given the nature of the strata. Main Investigation This will involve the collection and analysis of samples of soil, surface water, groundwater and soil gas in order to obtain all the information necessary for the assessment of human and environmental risks. The detail required will depend upon the objectives of the investigation. This will require a carefully designed investigation, which should take into account the information developed in the earlier stages of investigations and the objectives at this stage of the work. The further information and data should enable a full assessment of the risks presented by the contamination and also enable any containment or remedial actions to be properly designed with more accurate quantification of the costs. During the subsequent assessment of risks and hazards, all possible migration routes relevant to the contamination should be considered and a four dimensional picture (in space and time) of the contamination established. These requirements should be borne in mind when designing the main investigation, since to reach defensible conclusions, detailed knowledge of physical and chemical soil properties and of the local hydrology is essential. The amount and nature of the information required from the main investigation will vary depending on the nature of the site, the possible requirements for remedial action and the confidence required in the decision making process. The main investigation may involve some further targeted sampling points, for example, at areas of specific concern or to achieve delineation of contamination confirmed/detected in the exploratory investigation. However, the greater proportion of sampling points are normally non-targeted. Supplementary Investigation A review of the main investigation may still identify aspects where there is a deficiency of information, and, hence, a supplementary investigation will be required. This will be designed to produce quite specific information and will therefore utilise targeted sampling. When considering remedial options, it should be borne in mind that each method is likely to have its own data requirements and a supplementary investigation will be necessary to product this additional data. The ongoing monitoring of groundwater and ground gas wells is also sometimes classed as supplementary investigation. The situation may arise where the results of monitoring as part of the main investigation indicate that longer term monitoring will be beneficial in enabling a better assessment of the risks to be achieved. Validation sampling carried out to confirm the efficiency of remediation may incorporate some targeted sampling, located at areas of specific remediation, but will generally be non-targeted. APPENDIX A Examples of Potentially Contaminative Uses of Land Examples of the wide range of industries that might contaminate the land they are sited upon include: Smelters, foundries, steel works and metal processing and finishing installations Coal and mineral mining and processing, both deep mines and opencast Heavy engineering and engineering works; e.g. car manufacture, ship building Military/defence related activities Electrical and electronic equipment manufacture and repair. Gasworks, coal carbonisation plants, power stations. Oil refineries, petroleum storage and distribution sites Manufacture of organic and inorganic chemicals including pesticides, acids/alkalis, pharmaceuticals, solvents, paints, detergents and cosmetics Rubber industry including tyre manufacture Munitions and explosives production, testing and storage sites Glass making and ceramics manufacture Textile industry including tanning and dyestuffs Paper and pulp manufacture, printing works and photographic processing Timber treatment Food processing industry and catering establishments Railway depots, dockyards, garages, road haulage depots, airports Landfill storage and incineration of waste Sewage works, farms, stables and kennels Abattoirs, animal waste processing and burial of diseased livestock Scrap yards Dry cleaning purposes All types of laboratories Examples of other uses/types of land which might be contaminated: Radioactive substance used in industrial activities not mentioned above (e.g. gas mantle production and luminising works) Burial sites and graveyards Agriculture – excessive application or use in sensitive areas of fertilisers, pesticides, herbicides or fungicides Disposal of sewage sludge Natural contamination by radioactivity (including radon), concentrations of certain metal ions in excess, methane production in former coalmines etc. The DOE Industry Profiles contain more information on the likely types of contaminants expected from particular industrial and commercial sectors. These are not exhaustive in either covering all uses that have the potential to cause contamination or in covering all forms of contamination likely from a particular sector but will provide a useful starting point. APPENDIX B Phase I Reports – Checklist Please note: This list is not exhaustive. It is not always necessary for all the information on this checklist to be included in reports. Some information may not be relevant to your site. Type of information Site History Large scale OS maps (25” County Series + 1:2500 maps) Small scale OS maps (6” County Series + 1:10,000 maps) 1:1250 maps (certain urban areas only) Other maps Trade directories Aerial photographs Environmental Setting Geological maps (e.g. 1:10,000; 1:50,000; Applied Geology) Mining information Groundwater vulnerability maps Source Protection Zones Surface water bodies (including classification) SSSIs Regulatory Authorities SEPA – Groundwater River quality within 250m of site Discharge to controlled water within 250m of site Discharge to sewer consents within 250m of site Prosecutions under Water Resources Act 1991 within 250m of site Records of pollution events on/in vicinity of site Aquifer classification of geological strata underlying site including whether within Source Protection Zone Nearest surface water body, classification & distance from site Abstraction wells within 3km including source of water, purpose and quantity of water SEPA – Public Registers of IPC Processes + Radioactive Substances IPC Authorisations – Part A processes within 250m of site Radioactive substances authorisations within 250m of site Licensed waste disposal sites within 250m of site Public registers of IPC process + radioactive substances Trade effluent discharge consents within 250m of site Enforcements and prohibitions within 250m of site Prosecutions within 250m of site Revocations of authorisation within 250m of site SEPA – Waste Landfill sites and waste disposal sites within 250m of site (minimum ideally 500m) of site Waste transfer stations within 250m of site Closed landfill sites within 500m of site Register of scrap metal dealers Hazardous substance authority register site within 500m of site Type of waste accepted by those sites Planning (Hazardous Substances) Act 1990 consent sites within 250m of site Planning (Hazardous Substances) Act 1990 enforcements within 250m of site Local Authority Planning Department Planning history of site Vacant and Derelict Land surveys Environmental reports for record of remedial measures necessary as part of planning permission Information on locations for storage of hazardous materials Environmental Health Department Record of waste disposal licences (pre 1 April 1996) Records of closed landfill sites (pre 1 April 1996) Records of current pollution problems associated with closed landfill sites Application, authorisations, compliance and enforcement action under Part I of EPA 1990 including Part B Processes (pre 1 April 1996) Control of Major Accident Hazards (COMAH) Sites Trading Standards Flammable material held on site Petroleum storage tanks Notifiable installations Pipelines within notifiable distances Records of accidents and incidents involving petroleum HSE Records of accidents and incidents Emergency response records Previous Reports Previous work (site investigation, remediation etc.) carried out on site Previous reports available for review Previous reports summarised, taken into account and referenced Walkover Site layout Areas of potential contamination identified Inclusion of surrounding area visited Photographs Interviews Conceptual Model Conceptual model included Justified by results presented Any uncertainties discussed and objectives of Phase II identified Interpretation All sources, pathways and receptors identified All pollutant linkages identified Stated purpose of the report met Issues requiring site investigation identified Site investigation constraints identified Objectives of site investigation identified Site investigation health and safety issues identified Phase II Reports – Checklist Please note: This list is not exhaustive. It is not always necessary for all the information on this checklist to be included in reports. Some information may not be relevant to your site. Type of information Phase I Outputs Have the findings of Phase I been used to develop the objectives and strategy for Phase II? Has a copy of the client/contractor brief been included in the Phase II report? Phase II Strategy Is the aim of the investigation clearly defined? Is there a stated sampling strategy and what is it based on? (E.g. professional judgement, statistically derived etc.) Has sampling been undertaken as laid out in the sampling plan? (if not, why not e.g. obstructions) Are sampling locations clearly marked on a site plan? Were sampling locations surveyed? Are there stated procedures for sampling, handling, storage, collection and transport? Has a chain of command procedure been followed? Is there a clear analytical strategy drawn from conceptual site model to justify the analysis carried out on each sample? Characterisation of Site Site investigation data What type of ground investigations were carried out? (E.g. boreholes, window sampling, trial pits etc.) Have logs been included and of what quality? (E.g. soil and rock descriptions as BS5930) Have photographs been included? Is reinstatement suitable to prevent creation of new pathways? Field Tests What field tests were carried out? (E.g. hydrogeological tests, chemical tests, gas tests) Are reasons for testing stated? Were appropriate testing methods used? Was appropriate equipment used? Was equipment calibrated? Have results been reported adequately? Laboratory Analysis What type of laboratory tests were carried out? Was an accredited laboratory used? Are sample preparation and analytical methods reported? Are the laboratory results provided in a readable format? Are the results authorised by a lab supervisor? Is a lab interpretation of the results given? Results Have ground conditions been described? Have groundwater conditions been described? Have chemical results been described? Have variations in chemical results at depth and across the site been described? Have plots of variations in chemical results at depth and across the site been described? Have descriptive statistics of variations across the site been described? Conceptual Model Has a conceptual model been included? Is it justified by the results presented? Have generic guideline values been used? Have measured concentrations been compared with appropriate generic guideline values? Were the guideline values used correctly? Was the reasoning for use stated? Are all the contaminants covered by guideline values? What contaminant concentration was used for comparison (e.g. average, maximum, 95 UCL)? Are there any contaminants of concern not covered by guidelines? Are there any contaminants of concern where guideline values used are not appropriate? Do any of the contaminant levels exceed the guideline values? Site Specific Assessment Criteria (SSAC) Have SSAC been determined? If not, should they have been? Conclusions Interpretation of exceedance of assessment criteria Have the tests in Contaminated Land Report 7 (CLR7) been used to assess the significance of exceeding the guideline values? How has the extent of vertical and lateral contamination been determined? Are conclusions justified by data presented? Have uncertainties been identified? Recommendations Are recommendations provided for all issues identified in report? Are recommendations justified by data collected and conclusions drawn? APPENDIX C Recommended references This list is not exhaustive or exclusive, but indicates the more relevant guidance and information available. British Standard BS 10175:2001 Investigation of potentially contaminated sites – Code of Practice ISBN 0580 330907. Department for Environment, Food and Rural Affairs and the Environment Agency (2002). CLR7 Assessment of Risks to Human Health from Land Contamination: An Overview of the Development of Soil Guideline Values and Related Research. Environmental Agency. ISBN 1857 057325. Department of the Environment, Transport and the Regions and Environment Agency (2000). Model Procedures for the Management of Contaminated Land. Contaminated Land Research Report No11, London: DETR (in press). DoE Industry Profiles (1995) (Various titles). A list of the industries addressed can be viewed at http://www.defra.gov.uk/environmental/landliability/pubs.htm DoE Report CLR2 (1994 – 2 volumes). Guidance on preliminary site inspection of contaminated land. DoE Report CLR3 (1994) Documentary research on industrial sites. DoE Report CLR4 (1994) Sampling Strategies for Contaminated Land. Environment Agency Technical Report P5-066/TR (2000 – 2 volumes) Technical aspects of site investigation. ISBN 1 85705 5446 and ISBN 1 85705 5454 Environment Agency Technical Advice to Third Parties on Pollution of Controlled Waters for Part IIA of EPA 1990 Environment Agency Technical Report P5-066/TR (2000) Secondary model procedure for the development of appropriate soil sampling strategies for land contamination. Environment Agency and NHBC. Guidance for the Safe Development of Housing on Land Affected by Contamination. R and D 66. ISBNO-11- 310177-5. Scottish Executive. Planning Advice Note 33: Development of Contaminated Land. Scottish Executive Circular 1/2000 Environmental Protection Act 1990. SNIFFER (Scotland and Northern Ireland Forum for Environmental Research) Method for Deriving Site Specific Human Health Assessment Criteria for Contaminants in Soil (2003).