Issue Record. Revision Change Overview Reason for Change Date. Prepared By: Sarah Longstaff MSc Environmental Engineer.

Transcription

1 Phase I Land off Back Lane Dishforth David Holmes Properties Ltd Clint Harrogate HG3 3DR Sarah Longstaff BSc MSc Neil Taylor BSc CEng MIStructE MICE 10th December 2015 B20946/Phase 1

2 Issue Record Job Number: Prepared By: B20946 Checked By: Sarah Longstaff MSc Environmental Engineer Neil Taylor BSc (Hons) CEng MICE MIStructE Associate Date: 10 December 2015 Revision Change Overview Reason for Change Date i

3 CONTENTS 1 INTRODUCTION Sources of Information THE SITE Present Land Use SITE HISTORY Site History Summary GEOLOGY, HYDROLOGY AND HYDROGEOLOGY Geology Mining History Hydrology /Hydrogeology Soil Chemistry Arsenic Cadmium Chromium Lead Nickel INFORMATION HELD BY STATUTORY AUTHORITIES Landfill Sites Waste Management Facilities Contaminated Land Register Entries and Notices Local Authority Pollution Prevention and Controls Integrated Pollution Control (IPC) Authorisations Integrated Pollution Prevention and Control Permits (IPPC) Pollution Incidents Discharge Consents Contemporary Trade Directory Entries Fuel Sites Radon Environmentally Sensitive Areas Flooding Nitrate Vulnerable Zones... 5 ii

4 6 ADDITIONAL INFORMATION Services Site Investigation SUMMARY UK CONTAMINATED LAND LEGISLATIVE FRAMEWORK Legislation on Contaminated Land CONCEPTUAL MODEL General Potential On-site Sources of Contamination Potential Off-site Sources of Contamination Receptors Pathways Pollutant Linkages Risk CONCLUSIONS OF THE DESK STUDY RECOMMENDATIONS... 9 APPENDICES Appendix 1 ENVIROCHECK REPORT iii

5 DESK TOP STUDY REPORT B20946: Land off Main Street, Dishforth 1 INTRODUCTION This report is required to accompany a Planning Application for residential development on land on the outskirts of Dishforth. A proposed plan has not been provided at this stage. 1.1 Sources of Information Information on the above site has been obtained from a full Envirocheck Report centred on the site, examination of all the currently available historic maps of the site, and examination of the 1:50,000 British Geological Survey map of the area. Fig 1: Photograph showing view of proposed site looking towards Westlands Fig 2: Photograph showing view into site looking south toward the school Fig 3. Photograph showing view into site looking south west 1

6 2 THE SITE The site is an irregularly shaped area of land off Main Street, north west of Dishforth village. The northern two thirds of the site appears to be an arable field and the southern third a pasture with a rough track passing through the land. 2.1 Present Land Use The following observations were made: The southern third of the site is accessed via a grassed track off Grange Close. The site is rough grazing with hedgerows and sporadic mature trees along the boundaries. The northern part of the site is an arable field surrounded by mature hedgerows and sporadic trees. It is accessed from Main Street and slopes gently towards the east. The surrounding land uses are as follows: North West South East Road, with the A168 a further 100m to the north Arable land Arable land, residential properties and a school. RAF Dishforth is located 750m to the south. Residential properties, a road and a farm to the east of the road. 3 SITE HISTORY Examination of the published Ordnance Survey maps of the area revealed the following: Map Features Year Scale On-site Off-site :10,560 Farmland surrounded by hedgerows and sporadic mature trees. Road to the north, Methodist chapel to the north west of the road, residential properties to the east and south east, farmland to the south and west. No change. Virtually no change. Well located approximately 20m to the east :2,500 & 1:10, :2,500 No change. Virtually no change. Residential property built on north eastern boundary :10,560 No change. No change :10,000 No change. No change :10,000 No change. No change :2,500 No change. A168 to the north, substantial residential development in Dishforth village to the east and south east. School built to the south :10,000 No change. No change. 1993, 1994 & 1:2,500 No change. No change :10,000 No change. No change :10,000 No change. No change. 2

7 3.1 Site History Summary The historic map study shows that the site has been undeveloped since the earliest available map (1854). The village and road network has gradually developed since this time with the majority of the development post There appears to have been little redevelopment within the village. 4 GEOLOGY, HYDROLOGY AND HYDROGEOLOGY 4.1 Geology Examination of the published geological map of the area indicated that the site is underlain by Devensian Till which is part of the Vale of York Formation (British Geological Survey GeoIndex). This is a sandy clay, clayey sand and clay with gravel and boulders, with interbedded sand, gravel and laminated clay. The underlying bedrock is the Sherwood Sandstone Group. There are no records of mass movement or artificial ground close to the site. A borehole located on the northern side of the site indicates that the Till is 1.7m thick and confirms the presence of the Sherwood Sandstone beneath this. The British Geological Survey have indicated the following regarding ground hazards: Potential for collapsible ground stability hazards very low; Potential for compressible ground stability hazards no hazard; Potential for ground dissolution stability hazards no hazard; Potential for landslide ground stability hazards very low; Potential for running sand ground stability hazards very low; and Potential for shrinking or swelling clay ground stability hazards very low. 4.2 Mining History The site is not located in an area that might be affected by coal mining. 4.3 Hydrology /Hydrogeology The Envirocheck report indicates that the site is located on a Principal Aquifer with the superficial deposits classified as a Secondary Aquifer B. The Environment Agency define a Principle Aquifer as: layers of rock or drift deposits that have high intergranular and/or fracture permeability - meaning they usually provide a high level of water storage. They may support water supply and/or river base flow on a strategic scale. The Environment Agency define a Secondary B Aquifer as predominantly lower permeability layers which may store and yield limited amounts of groundwater due to localised features such as fissures, thin permeable horizons and weathering. These are generally the waterbearing parts of the former non-aquifers. The groundwater vulnerability has been assessed as of intermediate leaching potential (I1), defined as soils which can possibly transmit a wide range of pollutants. The site is not located in a source protection zone. 3

8 The nearest surface water feature is located 238m north west of the site. The nearest licensed groundwater abstraction is located 218m to the east of the site at The Gables. Groundwater is abstracted from the Sherwood Sandstone aquifer and is used for general farming and domestic purposes. There are a further seven licensed groundwater or surface water abstractions between 440m and 1000m from the site. These are for agricultural supplies, abstracting water from the Sherwood Sandstone aquifer, Soppa Gutter or Mother Syke Drain. 4.4 Soil Chemistry British Geological Survey (BGS) soil chemistry data sheets were obtained which present information on the topsoil concentration of five potentially harmful elements (PHEs) which under certain circumstances can pose a significant health risk to plants, animals and humans Arsenic The estimated Arsenic values for the site are less than 15mg/kg. The recommended Soil Guideline Value (SGV) for residential end use is 32mg/kg Cadmium The estimated Cadmium values for the site are less than 1.8mg/kg. The recommended Soil Guideline Value (SGV) for residential end use is 10mg/kg Chromium The estimated Chromium values for the site are 20 to 40mg/kg. The recommended Soil Guideline Value (SGV) for residential end use is 200mg/kg Lead The estimated Lead values for the site are less than 150mg/kg. The recommended Soil Guideline Value (SGV) for residential end use is 450mg/kg Nickel The estimated Nickel values for the site are less than 15mg/kg. The recommended Soil Guideline Value (SGV) for residential end use is 130mg/kg. 5 INFORMATION HELD BY STATUTORY AUTHORITIES This section details any relevant information held in the registers maintained by statutory bodies as identified in the Envirocheck Report. 5.1 Landfill Sites There are no landfill sites within 1000m of the site. 5.2 Waste Management Facilities There are no waste management facilities within 1000m of the site. 5.3 Contaminated Land Register Entries and Notices The Envirocheck Report does not identify any Contaminated Land Register Entries and Notices within 1000m of the site. 4

9 5.4 Local Authority Pollution Prevention and Controls There are no Local Authority Pollution Prevention and Controls within 1000m of the site. 5.5 Integrated Pollution Control (IPC) Authorisations There are no Integrated Pollution Control (IPC) Authorisations within 1000m of the site. 5.6 Integrated Pollution Prevention and Control Permits (IPPC) There are two Pollution Prevention and Control Permits (IPPC) within 1000m of the site. These have both been granted to a piggery located 877m to the east of the site. 5.7 Pollution Incidents There have been three pollution incidents within 1000m of the site. The first two were located 532m and 537m east of the site at Dishforth Sewage Treatment works and were discharges of oils into the Soppa Gutter. The third incident was 904m north west of the site and was a minor incident associated with the A Discharge Consents There are 11 discharge consents within 1000m of the site. The closest consent was located 236m to the north of the A168 and consented a trade discharge into a freshwater stream / river. This has been revoked. The next closest discharges have been granted to Yorkshire Water for the discharge of sewage effluent into the Soppa Gutter. This flows to the south east and away from the site. All other discharge consents are over 500m from the site. 5.9 Contemporary Trade Directory Entries There are four contemporary trade directories within 1000m of the site. The closest is a cabinet maker located 147m to the east. Airequip Automotive is located 171m to the east and A1 Tractors (two entries) are located 240m to the south east Fuel Sites There are no fuel stations with 1000m of the site Radon The site is situated in an area in which the British Geological Survey states that less than 1% of homes are above the action level. No radon protection measures are necessary in the construction of new dwellings or extensions Environmentally Sensitive Areas Flooding The agency and hydrological (flood) map shows that the site is not in an area that is affected by flooding from rivers or seas Nitrate Vulnerable Zones The site is located within a nitrate vulnerable zone for both surface and groundwater. This would only be applicable to agricultural usage of the site. 5

10 6 ADDITIONAL INFORMATION 6.1 Services These have not been examined as part of the Phase 1 report. Enquiries should be made to ensure that the site can be fully serviced and that there are no restrictions or easements across the site which would impede the proposed development. 6.2 Site Investigation No intrusive investigations have been undertaken. 7 SUMMARY From the historical map study, examination of information held by the statutory authorities and appraisal of site conditions from Google Earth, the site appears to have been farmland since the 1850s. The village of Dishforth has expanded since this time to border the site to the east and south. A new A road has been built just over 100m to the north of site. The site is located on low permeability Till deposits but the Sherwood Sandstone aquifer is located at relatively shallow depth below this. This is utilised as a groundwater source for nearby farms, but the site does not lie in a source protection zone. The site is not located in a flood zone. There does not appear to be any sources of contamination on the site or from the surrounding area. 8 UK CONTAMINATED LAND LEGISLATIVE FRAMEWORK 8.1 Legislation on Contaminated Land This section provides a conceptual model and qualitative assessment of the potential risks posed to human health and environmental receptors from potential on-site and off-site sources of contamination. The assessment is presented as a source-pathway-receptor model in accordance with Part IIA of the Environmental Protection Act Part IIA of the Environment Protection Act, 1990, which was enacted by section 57 of the Environment Act 1995 and the associated Contaminated Land (England) Regulations (SI 2000/227) was introduced on 1 April It created a new statutory regime for the identification and remediation of land where contamination poses and unacceptable risk to human health and environment. Part IIA provides a statutory definition of contaminated land: any land which appears to the Local Authority in whose area it is situated to be in such a condition by reason of substances in, on or under the land, that significant harm is being caused, or that there is a significant possibility of significant harm being caused, or that pollution of controlled waters is being or is likely to be caused. To determine whether land falls under the Part IIA definition of contaminated land the site should be evaluated in the context of a risk based framework. The assessment of contaminated land is typically a two-phase process which is initially based on a qualitative assessment of the likelihood of complete pollution linkages, with a quantitative element which seeks to determine the degree and the significance of the harm. Land is only defined as Contaminated Land if a significant pollutant linkage is present. 6

11 A pollutant linkage must comprise the following: Source - a contaminant at a concentration capable of causing adverse health or environmental effects. Receptor - there must be a human or environmental receptor present, which may be at risk of harm or impact from the source. Pathway - there must be an exposure pathway through which the receptor comes into contact with the contamination source. Each of these elements can exist independently but they create risk only when they are linked together, so that a particular contaminant affects a particular receptor through a particular pathway. The responsible authority then needs to consider whether the identified pollution linkage: is resulting in significant harm being caused to the receptor in the pollutant linkage; presents a significant possibility of significant harm being caused to that receptor; is resulting in the pollution of controlled waters, which constitute the receptor; or is likely to result in such pollution. If a pollutant linkage is demonstrated, then the Part IIA legislation provides powers for remedial action to be enforced by the Local Authority in whose area the contaminated land is situated. 9 CONCEPTUAL MODEL 9.1 General This section uses information the sources noted in section 1.1 to provide a conceptual model and qualitative assessment of the potential risks posed to human health and environmental receptors from potential on-site and off-site sources of contamination. The assessment is presented as a source-pathway-receptor model in accordance with Part IIA of the Environmental Protection Act Potential On-site Sources of Contamination The potential on-site sources of contamination are those relating to the use of chemical fertilisers and pesticides by the farmer. 9.3 Potential Off-site Sources of Contamination The potential off-site sources of contamination are those relating to the use of chemical fertilisers and pesticides by the farmer. 9.4 Receptors The primary receptors, considered to be potentially at risk from any identified contamination are as follows: Human Health Construction workers during the redevelopment phase; Residential end users; and Adjacent school. 7

12 Controlled Waters Groundwater stored within the Major Aquifer underlying the site. Surface waters are not considered as a receptor due to the distance to the nearest watercourse. 9.5 Pathways Potential contaminant migration pathways considered relevant to the site are: Human Health Ingestion of contaminated soils and dust particles; Direct physical contact with near surface soils and contaminated dust particles; Inhalation of wind blown contaminated dust; Inhalation of vapours and gases, migrating vertically into the atmosphere; and Inhalation of vapours and gases, migrating vertically into buildings and accumulating in confined spaces. Controlled Waters Contaminants impacting groundwater underlying the site via vertical leaching mechanisms. 9.6 Pollutant Linkages A 'pollutant linkage' describes the relationship between a contaminant, a pathway and a receptor, a 'pollutant' being the contaminant in a pollutant linkage. A contaminant, pathway and receptor must all be present for a pollutant linkage to exist, which forms the basis for determination that a piece of land is Contaminated Land. There is a source of contamination present at the site from pervious agricultural usage which could affect the identified Receptors. This should be assessed by further testing of the near surface. 9.7 Risk The risk in this case is expected to be LOW in terms of contamination. Soil chemical testing will determine the risk (if any) to the proposed development. If elevated levels are found then it is likely that a clean capping layer in soft landscaped areas will reduce the risk to an acceptable level for residential end use. 10 CONCLUSIONS OF THE DESK STUDY A review of the historic maps highlights that the site has been undeveloped since the 1850s. Potential on-sites sources of contamination are present on the site. Potential off-site contamination sources are not present. The soil chemistry data sheets show estimated natural values for Arsenic, Cadmium, Chromium, Lead and Nickel in the top soil to be below the recommended SGVs for residential end use. There are no landfill sites within 1000m of the site. The site overlies a major aquifer. 8

13 The agency and hydrological (flood) map shows that the site is not in an area that is affected by flooding from rivers or seas. No radon protection measures are necessary. Active pollutant linkages at the site are considered to be present. 11 RECOMMENDATIONS 1. Trial pits will be required to determine the near surface soils and depth to suitable foundation for the proposed structure. If the subsoils are granular in nature it may be necessary to investigate the site by boreholes to obtain SPT values for assessing the allowable bearing pressures. 2. Samples of near surface soils should be taken and tested to determine whether a pollutant linkage exists. The testing suite should include for assessing the levels of chemical fertilisers and pesticides. 3. Soils at proposed foundation level should be tested for sulphates and ph, in order to determine the concrete classes of buried concrete. 4. Should clay soils be encountered, then these should be tested for Plasticity Index and Moisture Content. 5. During construction and reduced level dig, careful observation should be made to identify any signs that the soils could be contaminated in terms of appearance or odour. Should this be encountered, then the Engineer must be informed immediately. 6. Should any soils be imported on to site, then these should come from a supplier who can provide necessary testing certificates or the soils should be sampled and tested, to verify that the soils are suitable for their intended use. 9