REPORT C4520 OCTOBER 2011
PRELIMINARY APPRAISAL REPORT (DESK STUDY) of EAST LEEDS HOUSING EXTENSION ALLOCATION, NORTH QUADRANT prepared for PERSIMMON HOMES YORKSHIRE, MR JOHN WILSON AND WHITE LAITH
REPORT C4520 REPORT FINAL NUMBER: STATUS:
REPORT PRELIMINARY APPRAISAL TYPE: REPORT (DESK STUDY)
REPORT OCTOBER 2011 DATE:
SITE: EAST LEEDS HOUSING EXTENSION ALLOCATION, NORTH QUADRANT PREPARED PERSIMMON HOMES FOR: YORKSHIRE, MR JOHN WILSON AND WHITE LAITH
PREPARED Sirius Geotechnical and Tel: 01132 649 960 BY: Environmental Ltd 4245 Park Approach Fax: 01132 649 962 Thorpe Park Leeds LS15 8GB
This report is written for the sole use of Persimmon Homes Yorkshire, Mr John Wilson and White Laith. No other third party may rely on or reproduce the contents of this report without the written approval of Sirius. If any unauthorised third party comes into possession of this report, they rely upon it entirely at their own risk and the authors do not owe them any Duty of Care or Skill.
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PRELIMINARY APPRAISAL REPORT (DESK STUDY)
of
EAST LEEDS HOUSING EXTENSION ALLOCATION, NORTH QUADRANT
Prepared for
PERSIMMON HOMES YORKSHIRE, MR JOHN WILSON AND WHITE LAITH
CONTENTS
EXECUTIVE SUMMARY
1. INTRODUCTION ...... 1
2. SITE DETAILS AND DESCRIPTION ...... 3
3. ENVIRONMENTAL SETTING ...... 5 3.1. Introduction ...... 5 3.2. Site History ...... 5 3.3. Published Geological Information ...... 8 3.4. Hydrology and Hydrogeology ...... 11 3.5. Landfilling and Waste Management...... 16 3.6. Radon Risk ...... 18 3.7. Other ...... 19
4. PREVIOUS INVESTIGATION FINDINGS ...... 21
5. PRELIMINARY CONCEPTUAL MODEL ...... 22
6. CONCLUSIONS AND RECOMMENDATIONS ...... 24 6.1. General ...... 24 6.2. Flood Risk ...... 24 6.3. Geotechnical ...... 24 6.4. Contamination Constraints ...... 25 6.5. Ground Gas ...... 25 6.6. Invasive Plants ...... 25
7. FURTHER INVESTIGATION ...... 26
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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TABLES
Table 2.1 Current Site Overview ...... 3 Table 3.1 Site History ...... 5 Table 3.2 Geological Summary ...... 9 Table 3.3 Surface Water Features ...... 11 Table 3.4 Groundwater Occurrence and Abstraction ...... 14 Table 3.5 Groundwater Vulnerability Status ...... 15 Table 3.6 Waste Management Activities ...... 16
APPENDICES
APPENDIX A FIGURES AND DRAWINGS
Drawing Title Scale No.
C4520/01 Site Location Plan 1:25,000
C4520/02 Site Features 1:10,000
C4520/03 Preliminary Conceptual Site Model NTS
NTS: Not to Scale
APPENDIX B GROUNDSURE REPORT
APPENDIX C CORRESPONDENCE
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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EXECUTIVE SUMMARY
Introduction Sirius Geotechnical and Environmental Ltd (Sirius) were commissioned by Persimmon Homes Yorkshire, acting on behalf of themselves, Mr John Wilson and White Laith, to undertake a preliminary investigation (desk study) of land referred to as “East Leeds, North Quadrant”, located in the Seacroft area of Leeds. Sirius were also commissioned to provide the related parts of an EIA, which will follow in a separate report. Proposals are for the development of the area for residential purposes and ancillary support uses. Site Details The site is a rotated “L” shape (orientated west to east in the north and north to south is the east) and has an approximate area of 94 hectares. The majority of the site is relatively flat and level, although the ground falls to the south and west in the south of the site (adjacent to Grimes Dike). Historically the site has been occupied by open farm land with some areas of trees and a few buildings, and this remains so today. There has been limited demolition of former buildings on site, and the filling of small former ponds. Ground surface comprises vegetated fields across the vast majority of the site. There are some areas of hardstanding, for instance in locations of existing buildings, and some areas of woodland. The western boundary of the site is formed by the A58 road, and the south eastern boundary by the A64 road. Red Hall Lane and Skeltons Lane form the southern boundary of much of the north of the site. Elsewhere, site boundaries are variously formed by hedges and wooded areas, open land and housing. The area around the site generally contains residential housing to the south and west and open fields to the north and east. A fuel filling station is located close to the north western site boundary. Many mature trees and bushes are present within the site and along site boundaries. Site History The earliest maps reviewed here (1891 to 1893) show the site predominantly as farm land with localised farm buildings. There have been little changes to the site layout over time, although some buildings have been demolished and ponds etc have been infilled. Potentially contaminative sources identified in the vicinity of the site include an electricity sub station at Bramley Gardens and electricity transformers on poles in various locations at the site, filled ponds and possible made ground (including at the site of the former Providence Farm) and the potential use of herbicides, pesticides, fuels and lubricants etc associated with farm activities. In addition, there has been some filling of off-site land within 250m, and a fuel filling station is located close to the north west of the site. Anticipated Based on published geological mapping for the area and information in the Ground GroundSure report, drift geological deposits comprising Till are present across the Conditions vast majority of the site. A small area of Head is present in the south west of the site (adjacent to Grimes Dike), and the land to the east of this is shown as not containing drift deposits. The solid geological deposits comprise sandstones, mudstones and siltstones of the Millstone Grit Group and the Lower Coal Measures. Faults are present across the site. Based on the history of the site and our experience of similar sites, it is considered likely that a layer of made ground may be present at the locations of current and former buildings, infilled ponds etc.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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Mining & Review of information contained with the GroundSure Report has shown no former Quarrying mining or quarrying activities at the site or in the immediate vicinity. BGS mapping indicates that part of the site however lies in an area of possible shallow coal workings, annotated with “shallow hollows” on the 1:10,000 scale geological plan. Foundations The nature and depth of foundations will be dependent on the detailed site geology, including: • Thickness of any made ground; • Presence of worked coal deposits; • Presence and extent of basements, underground storage tanks and other underground features; • Bearing capacity of the natural strata; • Groundwater levels; and, • Proximity to trees where potentially shrinkable soils are present. At this stage, where gradients allow, shallow spread foundations are generally anticipated. It is recommended that a site investigation is carried out to confirm foundation requirements. Contamination The preliminary conceptual site model indicates that pollutant linkages are possible to a variety of receptors. Potential heavy metals, organic and inorganic contaminants and asbestos fibres within the made ground and shallow soils may pose a potential risk to construction workers, site end users and controlled waters. Extensive remediation is not anticipated. It is recommended that a site investigation is carried out to address these matters. Gas Risk Based on the information currently available, it is considered that there is potential for ground gas generation, accumulation and migration to occur as a result of the presence of filled ground (on and off site) and from possible shallow coal workings. It is recommended that a site investigation is carried out to address these matters. According to the BGS, radon protective measures are not required for the site. Further Works The following ground investigation works should be undertaken to confirm foundation design and determination of any contamination constraints: • Trial pits to investigate near surface soil and groundwater conditions and allow recovery of soil samples for testing. • Soakaway testing within selected trial pits to determine the suitability of soakaways as part of a SUDS for the site. • Drilling of cable percussive or window sample boreholes to prove sufficient natural strata for founding purposes for the proposed development. To include Standard Penetration Tests (SPTs) in order to provide geotechnical data for the underlying strata. • Installation of gas and groundwater monitoring wells in selected boreholes. • Drilling of rotary open boreholes to investigate potential shallow coal workings. • Chemical and geotechnical laboratory testing to adequately categorise the shallow soils. • Gas monitoring program (6 visits over 3 months anticipated). • Reporting. A pre-demolition asbestos survey will be required prior to any demolition of the existing buildings on site.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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1. INTRODUCTION
Sirius Geotechnical and Environmental Ltd (Sirius) were commissioned by Persimmon Homes Yorkshire, acting on behalf of themselves, Mr John Wilson and White Laith, to undertake a preliminary appraisal (desk study) of land referred to as “East Leeds, North Quadrant”, located in the Seacroft area of Leeds. The land is henceforth referred to as the “site”. In addition, Sirius were commissioned to complete the related section of an Environmental Impact Assessment (EIA) for the site, which will be presented in a separate report.
It is understood that these reports are required in support of an outline planning application for residential development and ancillary support uses at the site.
The objectives of the preliminary appraisal were:
• To establish the historical development of the site and immediate surrounding area from a review of historical Ordnance Survey (OS) plans;
• To establish the environmental setting of the site;
• To evaluate whether past mining or other extractive industries could have an influence on the site;
• To determine whether historical or current activities could give rise to significant ground contamination;
• To determine the potential risk to the development from hazardous ground gas sources including radon;
• To make provisional recommendations for foundations and measures to deal with potential contamination; and,
• To provide recommendations for intrusive works required to confirm the ground conditions below the site, the contamination status of the shallow soils, and foundation solutions and measures to deal with any contamination.
In addition, the data gathered will be used in the preparation of an EIA as noted above.
This desk study includes an assessment of information provided by GroundSure Environmental reports (GroundSure), Leeds City Council, The Coal Authority and the British Geological Survey
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(BGS). At the time of writing, full responses have not been received from all Leeds City Council departments. A site inspection (walk over survey) was undertaken by a Sirius geoenvironmental engineer on 7th October 2011. For reasons of discretion, this inspection was predominantly undertaken from adjoining roads, footpaths etc.
This report presents and interprets the factual information reviewed during this investigation and presents a Preliminary Conceptual Site Model (PCSM) from which ground-related hazards and risks have been assessed.
It has been assumed in the production of this report that the site is to be developed for a residential with gardens end use. In addition, it is assumed that ground levels will not change significantly from those described in this report. If this is not the case, amendments to the recommendations made in this report may be required.
Where the report refers to the potential presence of invasive plants (such as Japanese Knotweed) or asbestos-containing materials, such observations are for information only and should be verified by a suitably qualified expert.
This report has been prepared for the sole use of Persimmon Homes Yorkshire, Mr John Wilson and White Laith. No other third party may rely upon or reproduce the contents of this report without the written approval of Sirius. If any unauthorised third party comes into possession of this report, they rely on it entirely at their own risk and the authors do not owe them any Duty of Care or Skill.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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2. SITE DETAILS AND DESCRIPTION
Table 2.1 Current Site Overview
Location The site is located in the Seacroft area in the north east of Leeds, between the A58 road in the west to the A64 road in the east. A site location plan is included as Drawing No. C4520/01, within Appendix A.
National Grid Reference The site is centred at approximate NGR E 436400 N 438200.
Topography and The site has a broadly right-angled shape, orientated west to east Features in the north and north to south in the east. The majority of the site is broadly flat and level, although in the southern area of the site the land slopes to the south and south west, toward Grimes Dike. Ordnance Survey mapping shows the northern area of the site at an elevation of around 125m AOD, with Grimes Dike being at 98m AOD at the A64 road.
With the exception of buildings at Bramley Gardens and Bramley Grange Farm, the site comprises undeveloped land. Land uses variously include arable farming, livestock farming (cows and sheep present, but no significant barns or other livestock-related facilities seen), areas of mature woodland and areas of unused land with scrubby vegetation.
The site is crossed by a number of overhead electricity cables, including high voltage cables on large pylons. “Cable on pole” installations are also present in the northern area of the site, including transformers on at least one pole (close to the former Providence Farm – see below). Another possible transformer was noted close to the Lake Side area in the north west of the site, although close observations could not be made to confirm this. In a number of cases, both high voltage cables and “cable on pole” cables transferred to underground within the site boundaries. The presence of pylons and overhead cables may represent a development constraint.
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A mobile telephone mast and associated facilities is present on Coal Road where it crosses the northern site boundary.
A sign at Bramley Grange Farm shows the presence of kennels and a cattery, and from the road it was possible to observe a number of large agricultural style buildings with corrugated walls and roofs (possibly of asbestos material).
Buildings were present at Bramley Gardens, but a close inspection was not possible. From an adjacent path it was possible to view what appeared to be an electricity sub station. A large agricultural barn is present to the south of Bramley Gardens.
Approximate Site Area 94 hectares.
Site Boundaries Site boundaries are made up of the A58 road in the west, open fields in the north and north east, the A64 road in the extreme south east and open space and housing in the south west and west. The southern boundary of the northern area of the site is formed by Red Hall Lane and Skeltons Lane, and Skeltons Lane divides the northern area of the site from the southern area. Many of the site boundaries and internal field boundaries are formed of trees and bushes.
Current Land Use Predominantly farm land and open space, with some buildings at Bramley Gardens and Bramley Grange Farm.
Invasive Plant Species None noted, although due to the size of the site a thorough inspection could not be made. An ecological survey should be carried out if not previously undertaken to confirm if any invasive plant species are present.
Adjacent Land Uses Open fields to the north, east and south east. Housing and further open space to the south and west. Overgrown partly filled ground and a fuel filling station are located immediately to the north west of the site.
The main site features are shown on Drawing No. C4520/02 within Appendix A.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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3. ENVIRONMENTAL SETTING
3.1. Introduction
Published environmental, geological and historical data relating to the site has been reviewed. A summary of relevant information is provided below and a copy of the GroundSure report is enclosed in Appendix B.
3.2. Site History
Table 3.1 presents a summary of the site history as obtained predominantly from 1:10,560 and 1:10,000 scale OS mapping dated 1891 to 2011. Where features of particular interest have been identified from these maps, they have been investigated further by review of larger scale mapping (1:2,500).
It is not the intention of this report to describe in detail all of the changes that have occurred on, or adjacent to the site, only those pertinent to the proposed development.
Table 3.1 Site History
Map Dates On-Site Features Off-Site Features (only features within 500m that may affect the site are listed) 1891 - 1893 The site is shown as predominantly A pond feature is shown at “Lake Side” open space (presumably farm land), immediately to the north west of the with some areas of trees. site. A smithy is shown immediately to the west of this. Providence Farm is shown in the north west of the site. Two tanks and a A quarry and separate infilled quarry possible pump (a “P” symbol is are shown approximately 250m north indicated) are shown at the farm. west of the site.
Buildings associated with Bramley Springs are shown approximately Grange Farm straddle the eastern site 200m north east of the site, and a well boundary. A possible pump (“P” a similar distance to the east of the symbol) is also shown. site.
A road coincident with the current Coal An area of marshy ground, associated Road crosses the site in a north to with Grimes Dike is shown adjacent to
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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Map Dates On-Site Features Off-Site Features (only features within 500m that may affect the site are listed) south orientation in the west of the the south west of the site. A well, tank site, and Red Hall Lane – Skeltons and weir are also shown here, and the Lane crosses the east of the site in an marshy ground is shown as being east to west orientation and extends to retained by an embankment in the the west to form the southern south. boundary of the northern area of the Redhouse Farm is shown across Red site. Hall Lane to the south of the north Two small discrete ponds are shown in west of the site. the east of the site, and a feature subsequently shown as a pond is indicated approximately 150m east of Providence Farm.
1906 A windpump in shown on the northern An old burial ground is shown site boundary, north of Providence approximately 300m west of the Farm. western area of the site.
Grimes Dike is aligned close to the south western site boundary.
1934 The ponds in the east of the site are The area of marshy ground is no no longer shown. Linear features longer shown, although the weir and subsequently indicated as drains cross embankment remain. the eastern area of the site. The smithy is no longer indicated.
The previously unfilled quarry to the north west of the site is now shown as being occupied by trees.
1938 No significant change. Housing is shown to the south west of the western extremity of the site, and to the north of Lake Side.
1950 The windpump on the northern site Further housing is shown to the west boundary is no longer shown. of the site.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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Map Dates On-Site Features Off-Site Features (only features within 500m that may affect the site are listed) 1964 - 1968 A group of buildings indicated as The water feature at Lake Side is “Whinmoor” is shown in the centre of shown as being smaller than the site. Linear drain features are previously shown, potentially indicating shown in the north of the site and in some filling. The larger of the two the south east. quarries to the north west of the site is shown as having a refuse tip A pond is shown associated with associated with it on the 1964 map. Providence Farm (this may have been The two quarries are not shown on the present at earlier times but not 1968 map. indicated as such). The old burial ground is no longer shown.
Further housing and industrial land (works, depot, factory etc) are shown to the west and south west of the site.
1975 - 1980 Providence Farm is no longer shown, Further housing developments are although the pond remains present. shown to the south west of the site.
The embankment associated with the marshy ground at Grimes Dike is no longer shown, and issues are shown flowing to the east, towards Grimes Dike.
1984 - 1985 The pond at the location of the former Further housing developments are Providence Farm is no longer shown. shown to the south west of the site.
1993 - 2011 The buildings at Whinmoor have The refuse tip is no longer shown undergone rearrangement and are associated with the quarry to the north now indicated as Bramley Gardens west of the site. (possibly housing). An electricity sub Further housing developments are station is shown in this area. shown to the south west of the site. Maps of 2002 show a number of
drains on site boundaries and within
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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Map Dates On-Site Features Off-Site Features (only features within 500m that may affect the site are listed) the site.
No detail is shown in the south east of the site.
Sept 2011 (from site A further building is shown associated No significant change shown on visit and Ordnance with Bramley Gardens. mapping. Survey mapping)
During the site inspection, the land at the former Providence Farm was noted as containing scrubby vegetation and the ground surface was slightly irregular, but there was no significant evidence of settlement, vegetation die-back etc.
Leeds City Council Sustainable Development Unit (LCCSDU) has also commented that historical maps available to them show the site as open fields from sometime before 1849 (i.e. on earlier maps that included in the GroundSure report provided to Sirius).
In summary, the site appears to have had a predominantly open / agricultural history, with some farms and other buildings, plus ponds. Off site usage has shown a general increase in residential and industrial development, as well as filling of ponds and quarries.
3.3. Published Geological Information
A summary of available published geological information is provided in Table 3.2 below.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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Table 3.2 Geological Summary
Sources of BGS 1:50,000 scale geological map (Sheet 70, showing solid and drift Information deposits).
BGS 1:10,000 scale geological map (Sheet SE 33 NE).
BGS lexicon of named rock units.
BGS on-line borehole records.
BGS Technical Report WA/92/1 “Leeds: A geological background for planning and development”, plus associated maps.
Made Ground The geological maps show made ground in the proximity of the former Providence Farm (likely associated with the former pond and structures), as well as at the location of the former Lake Side and the area of former marshy ground at Grimes Dike (these latter two areas being off-site, but adjacent to site boundaries).
Drift Geology The majority of the site is shown as being covered by Till deposits (stony, sometimes sandy, clay), although Head deposits (pebbly silt) are shown in the location of Grimes Dike and marginally encroach on to the south of the site.
There is an area of the site to the east of Grimes Dike where no drift deposits are shown as being present.
Solid Geology Review of BGS Applied Geological Mapping Sheet for Leeds (SE23/33, Map 2: Solid Geology at 1:25,000 scale) shows that the site is underlain by strata of Carboniferous age, comprising Rough Rock (sandstone) of the Millstone Grit Group, Elland Flags (sandstone) of the Lower Coal Measures and undifferentiated mudstone and siltstone of the Lower Coal measures. The site is crossed by number of faults, generally orientated north east to south west.
The BGS 1:10,00 scale sheet SE 33 NE notes shale in the vicinity of Grimes Dike.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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BGS Borehole Exploratory hole records provided by the BGS (available on-line), have Records been reviewed for boreholes drilled along the alignment of the A64 close to the site boundary.
Boreholes reviewed from this area (BGS borehole references SE33NE1209, SE33NE1210 and SE33NE1216) indicate a general sequence of topsoil, subsoil and clay overlaying Glacial Till deposits. The Glacial Till was encountered at depths of 0.45 to 0.6m depth, and the material extended to below the base of each of the boreholes (the deepest was drilled to 8.3m depth). The Glacial Till was variously described as a sandy or very sandy clay, with gravel and cobbles noted.
Groundwater conditions in the boreholes were variable, with one borehole (SE33NE1209) recording no significant groundwater, one (SE33NE12100) recording a number of inflows from 2.5m depth and below (resting at 4.5m depth) and one (SE33NE1216) recording a number of seepages associated with sand and gravel bands in the Glacial Till, with the rest groundwater level at 3.6m.
It should be noted that these boreholes are all drilled in close proximity of each other in the south of the site and may not represent ground conditions elsewhere at the site.
BGS map SE 33 NE includes details of a well sunk in the north west of the site, possibly in connection with the former windpump close to Providence Farm. The well was sunk to 72m depth, with materials encountered variously described as “strata”, “Galliard” (understood to be a term for sandstone), and “Bind” (mudstone). No reference is made to coal deposits.
Mining and A report provided by the Coal Authority states that the site is not within Quarrying the zone of likely physical influence on the surface from past or present underground workings, and that there are no known coal mine entries within, or within 20 metres of, the boundary of the property.
Additionally, the site is not within the boundary of past or present opencast mines. The Coal Authority has not received a damage notice or claim related to the site, and there is no record of a mine gas emission requiring action by the Coal Authority within the boundary of the site.
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A copy of the Coal Authority Report is included in Appendix C.
Although some quarrying has been identified in the general site vicinity, inspection of historical OS plans has not revealed any evidence of quarrying/pits beneath the site.
The GroundSure (GeoInsight) report notes that various solid geological deposits at and within 1km of site (sandstones and vein material) may have been subject to non-coal mining, but in all cases the assessment of likelihood of this mining having taken place is noted as ‘Rare’ or ‘Highly Unlikely’.
3.4. Hydrology and Hydrogeology
A summary of available information pertaining to hydrology and hydrogeology is presented in Tables 3.3 to 3.5 below.
Table 3.3 Surface Water Features
Presence/Location Comments
EA GQA The GroundSure report contains no Classified details of Environment Agency river Watercourses quality (biological quality) information for (within 1.5km) the area up to 1.5km from the site.
Chemical quality is provided for a water course 1051m north of the site. For the period 2005 to 2009 (latest date of information provided) the chemical quality of this water course was described as “A” (very good). OS 1:50,000 scale mapping indicates water courses this approximate distance to the north of the site, but does not name these features. These water courses appear to flow to the north east.
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Presence/Location Comments
Unclassified The GroundSure report shows Watercourses watercourses on the northern site (within 500m) boundary (unnamed water feature flowing west to east), and also on the south western boundary (Grimes Dike, flowing to the south east).
There are a number of other watercourses recorded within 500m of the site, including Primary, Secondary and Tertiary rivers, as well as culverts and drains, although it is noted that a number of these are contiguous with each other and form different stretches of the same watercourses.
Surface Water The GroundSure report notes the It is possible that these water Features presence of surface water features on features represent the drains (Canals, Ponds, the site and within 250m of the site, but noted on recent and historical Lakes, etc.) does not provide any further details. mapping of the site. (within 250m) From the site inspection (which was conducted mainly from adjacent roads and paths) it was possible to observe a number of open drains on site boundaries. These were notes as being dry at the time of observation. OS mapping indicates drains and ponds on the site although it was not possible to confirm the presence of these from the site inspection.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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Presence/Location Comments
Flood Risk From the GroundSure report, the site is The GroundSure report notes Status not indicated as being within the that the Low confidence indicative Zone 2 or Zone 3 floodplain, classification of the groundwater and these floodplains do not encroach flooding designation indicates within 250m of the site. that this information should be treated with caution. The GroundSure report does note that the site (including areas extending 50m beyond the site boundaries) has a Very High susceptibility to groundwater flooding, although this is accompanied by a note that the confidence in this classification is Low.
Other The GroundSure report notes no surface water abstraction licences within 1km of the site.
From the site inspection, it was noted that Grimes Dike runs in a culvert within the housing area to the west of the site, before entering an open stream close to the south western site boundary.
Environment Agency GQA assessments: A = very good to E = poor
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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Table 3.4 Groundwater Occurrence and Abstraction
Presence/Location Comments
Licensed Abstractions The GroundSure report indicates The closest licensed (within 500m) no groundwater abstraction groundwater abstraction is 645m licences within 500m of the study west of the site (water for spray site. irrigation from Millstone Grit strata).
Source Protection The GroundSure report indicates
Zones (within 500m) no groundwater Source Protection Zones within 500m of the site.
Springs/Potable Water The GroundSure report indicates A number of springs have been
Abstractions (within 2km) no potable water abstraction identified from historical mapping licences within 2km of the site. within and outwith the site. Those within the site are not shown on more recent mapping.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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Table 3.5 Groundwater Vulnerability Status
Environment Agency Classification
Groundwater The Till drift deposits are described as ‘Unproductive Strata’ under the Classification EA’s aquifer classification system, while the Head deposits are ‘Secondary (undifferentiated) Strata’.
All of the solid geological strata at the site are given ‘Secondary A Aquifer’ classification.
‘Unproductive Strata’ are defined as ‘rock layers or drift deposits with low permeability that have negligible significance for water supply or river base flow’.
The ‘Secondary (undifferentiated) Strata’ classification is assigned to geological materials ‘which have previously been designated as both minor and non-aquifers in different locations due to the variable characteristics of the rock type’.
A ‘Secondary A Aquifer’ is defined as ‘permeable layers capable of supporting water supplies at a local rather than strategic scale, and in some cases forming an important source of base flow to rivers. These are generally aquifers formerly classified as minor aquifers’.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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3.5. Landfilling and Waste Management
Table 3.6 Waste Management Activities
Presence / Location Comments
Local Authority The GroundSure report indicates This feature correlates to the Recorded Landfills one local authority landfill located refuse tip noted in the review of (within 1.5km) 205m north west of the site. This historical mapping above. is recorded as a Refuse Tip.
LCCSDU has commented that this site was used from mid 1958, and given its small size it is likely that the site was not open for very long. The site was used for the disposal of domestic and trade waste.
BGS / EA Recorded The GroundSure report notes no The landfill recorded 183m north
Landfills (within 1.5km) current operational landfills with west of the site correlates to the 1km of the site. refuse tip noted in the Local Authority Recorded Landfills and Two EA-recorded historic landfills in the review of historical are noted within 1.5km of the site. mapping above. The The first is recorded 183m north differences in distance are due west of the site and was licensed to how the data has been to receive commercial and recorded by the original data household waste. The licence is suppliers. noted as surrendered.
The second is recorded 1348m south west of the site and received inert and commercial waste. The licence was surrendered in 1984.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
Preliminary Appraisal Report – October 2011 Page 17
Presence / Location Comments
Other Licensed Waste The GroundSure report notes no Management Facilities operational or non-operational (within 1.5km) waste treatment, transfer or disposal facilities within 500m of the site.
The GroundSure report does note the presence of 12 licensed waste treatment, transfer or disposal facilities between 500m and 1.5km from the site. The closest of these (related to a mobile plant licence) is located 597m south of the site, but the licence is noted as having been surrendered. The closest facility with a non-surrendered licence is 811m south of the site and relates to a physical treatment facility at Elida Faberge Ltd.
Evidence of Landfilling As noted above, based on the On or Within 250m of GroundSure map and historical Site mapping, landfilling is indicated in connection with the former quarries noted to the north west of the site.
Ponds are known to have been present on and in close proximity to the site (Providence Farm, Lake Side etc), but the nature of any materials used to infill these is not currently known.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
Preliminary Appraisal Report – October 2011 Page 18
Presence / Location Comments
Site Inspection A detailed inspection of the whole Evidence of Fly- site area was not possible. Tipping on Site? However, during the site inspection fly-tipped waste was noted in, and close to, an open drain on the western side of Coal Road.
Ground Gas Risk Gas risk assessment required. The localised presence of Assessment ground gas from localised fill Required? materials at the site and in close proximity (i.e. as a result of infilling of pond features etc) cannot be discounted at this stage. In addition, the infill of the quarries to the north west of the site could theoretically represent a source of ground gas.
If shallow coal deposits are present, these again could represent a source of ground gas.
3.6. Radon Risk
To determine whether the site is at risk from radon gas, the BRE Document “BRE 211 - Radon: Guidance on the protective measures for new dwellings” together with the National Radiological Protection Board (NRPB) “Radon Atlas of England and Wales” have been referenced.
These documents, together with a geological assessment contained within the GroundSure (GeoInsight) report, which includes information obtained from the Health Protection Agency (HPA) and British Geological Survey, state that the site lies within an area in which radon protective measures are not required.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
Preliminary Appraisal Report – October 2011 Page 19
3.7. Other
Other potentially contaminative activities or environmental constraints are listed below. The entries relate to activities within approximately 250m of the site, with the exception of COMAH and NIHHS facilities where the assessment is extended to a distance of approximately 500m from the site.
• No historic IPC Authorisations or Part A(1) and IPPC Authorised Activities are recorded within 250m of the site.
• There are two Part A(2) / Part B Activities recorded within 250m of the site. The first of these relates to Red Hall Service Station (43m north west of the site). The second relates to Coronation Service Station, located 80m south west of the site. The GroundSure report notes that Red Hall Service Station was issued with an Enforcement Notice under section 80 of the Environmental Protection Act on 22 March 2007. Further details of the reason for this notice are not provided. These two locations are the only fuel sites recorded within 500m of the site.
• There is one Licensed Discharge Consent within 250m of the site. This is located 40m west of the site and discharges to Grimes Dike, which is adjacent to the site.
• One Notification of Installations Handling Hazardous Substances (NIHHS) authorisation is recorded within 500m of the site, this being located 484m south west of the site and issued to Elida Gibbs Ltd. There are no COMAH authorisation facilities within 500m of the site.
• The GroundSure report includes details of seven recorded pollution incidents within 250m of the site. Of these, three are recorded as having occurred on the site itself, as follows:
• An incident involving oils and fuel in the general location of Bramley Gardens, dated 29 November 2002. This was classified as having minor impact to land and no impact to water or air.
• An incident involving unidentified oil on the western boundary of the site approximately 350m south west of Bramley Gardens, dated 23 November 2002. This was classified as having minor impact to water and no impact to land or air.
• An incident involving crude sewage in the south of the site close to Grimes Dike, dated 10 February 2002. This was classified as having minor impact to land and no impact to water or air.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
Preliminary Appraisal Report – October 2011 Page 20
• The remaining four recorded pollution incidents occurred at distances between 16m and 244m from the site and variously involved ‘grey water’, ‘other contaminated water’ and ‘vehicles and vehicle parts’, with the pollutant at one incident not being identified. None of these resulted in impacts more significant that minor impacts.
• The GroundSure report notes two potentially contaminative activities or features located on the site, these being related to a pylon and an electricity sub station in the area of Bramley Gardens. Within 250m of the site boundaries, a further 12 potentially contaminative activities or features are recorded, these including fuel stations and car washes, electricity sub stations etc. The closest of these is at Red Hall Service Station, as discussed above.
• There are no Part A(1) and IPPC authorised activities, Category 3 or 4 Radioactive Substance Licenses or Planning Hazardous Substance Consents within 500m of the property.
• The extreme north eastern area of the site is recorded as being located within a Nitrate Vulnerable Zone, which extends to the north and north east and borders much of the north of the site.
• Leeds City Council Sustainable Development Unit (LCCSDU) has commented that it currently has no reason to determine the site as Contaminated Land under the provision of Part 2A of the Environmental Protection Act 1990.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
Preliminary Appraisal Report – October 2011 Page 21
4. PREVIOUS INVESTIGATION FINDINGS
No previous investigations have been provided to Sirius.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
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5. PRELIMINARY CONCEPTUAL MODEL
Based on the desk study, combined preliminary conceptual site models and conceptual exposure models (CSM) have been developed for the proposed future residential land use. This section summarises the understanding of surface and sub-surface features, the potential contaminant sources, transport pathways and receptors in order to assess potential pollutant linkages.
Potential sources of contamination at this site include:
• The presence of the electricity sub station in the Bramley Gardens area of the site and the transformer on poles noted at the site (potentially containing polychlorinated bi-phenyls – PCBs).
• Pesticides and herbicides related to the agricultural use of much of the site area.
• The likely presence of localised areas of made ground , associated with present and former structures, infilled ponds etc.
• Asbestos from current and former buildings.
• Ground gas from filled ground (on and off site ponds, marshy ground) and from possible shallow coal deposits.
• Fuels, lubricants etc associated with the use and maintenance of farm machinery.
• Fuels etc related to the fuel filling station noted to the north west of the site.
A qualitative risk assessment has also been made of the likelihood of any complete pollutant linkage and its potential significance.
The preliminary conceptual model for the site is presented in schematic form as Drawing No C4520/03 in Appendix A.
In summary, the preliminary CSM has identified the following potential pollutant linkages which could result in an unacceptable risk to the proposed end-use, as identified below:
• Ingestion, inhalation of dust and dermal contact with heavy metals, asbestos fibres, inorganic and organic contaminants (PCBs), within made ground and natural soils.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
Preliminary Appraisal Report – October 2011 Page 23
• Generation, migration and accumulation of gasses and vapours that could result in explosive and / or toxic environments being created.
• Leachable heavy metals, inorganic and organic contaminants (including PCBs) in made ground and / or shallow soils, with the potential to impact controlled waters (Secondary Aquifers in the Head deposits in the south of the site and in the solid geological strata beneath the site, plus Grimes Dike).
• Migration of liquid phase contaminants to the controlled waters noted above.
Currently, the risk associated with each of these linkages is considered as low or low to moderate.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
Preliminary Appraisal Report – October 2011 Page 24
6. CONCLUSIONS AND RECOMMENDATIONS
6.1. General
It is understood that consideration is being given to the construction of a residential development with ancillary support uses at the site.
6.2. Flood Risk
The site is not recorded as being within indicative Zone 2 or Zone 3 floodplains. Although the site is noted as having a Very High susceptibility to groundwater flooding, the confidence in this classification is noted as Low, and the information should be treated with caution.
6.3. Geotechnical
Mining and Quarrying
Review of the GroundSure report and historical mapping has shown no presence of mining or quarrying activities at the site or in the immediate vicinity. BGS mapping indicates that part of the site however lies in an area of possible shallow coal workings, annotated with “shallow hollows” on the 1:10,000 scale geological plan.
Foundations
The nature and depth of foundations will be dependent on the detailed site geology, including:
• Thickness of any made ground.
• Presence of worked coal deposits.
• Presence and extent of basements, underground storage tanks and other underground features.
• Bearing capacity of the natural strata.
• Groundwater levels.
• Proximity to trees where potentially shrinkable soils are present.
At this stage, where gradients allow, shallow spread foundations are generally anticipated.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
Preliminary Appraisal Report – October 2011 Page 25
It is recommended that site investigation is carried out in order to provide further information regarding these matters and to allow foundations to be designed.
6.4. Contamination Constraints
Risk Evaluation for the Proposed Land Use (Residential with Plant Uptake)
The preliminary conceptual site model indicates that pollutant linkages are possible to a variety of receptors. Potential heavy metals, organic and inorganic contaminants (including PCBs) and asbestos fibres in made ground and shallow soils may pose a potential risk to construction workers, site end-users and controlled waters. In addition, vapours associated with the possible storage of fuels etc may also present a risk to construction workers and site users. Risks related to these potential linkages are currently given a qualitative assessment as “low”. The precise nature of the risks should be investigated further through site investigation.
If the existing buildings on site are to be demolished, a pre-demolition asbestos survey should be undertaken prior to the demolition works.
6.5. Ground Gas
Based on the ground conditions identified on published geological mapping for the area and the history of the area, it is considered that there is potential for ground gas generation, accumulation and migration to occur as a result of the presence of filled ground (on and off site) and from possible shallow coal workings. Risks related to these potential linkages are currently given a qualitative assessment as “low to moderate”. The precise nature of the risks should be investigated further through site investigation.
According to the BGS, radon protective measures are not required for the site.
6.6. Invasive Plants
Invasive plant species were not observed during the site inspection, although a close inspection was not carried out due to the need for discretion at this stage.
It is recommended that the presence of invasive plant species is confirmed by a qualified consultant ecologist and their advice taken on appropriate treatment. The treatment of any invasive species should take place in advance of the proposed construction works.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith
Preliminary Appraisal Report – October 2011 Page 26
7. FURTHER INVESTIGATION
The following ground investigation works should be undertaken to confirm foundation design and determination of any contamination constraints:
• Trial pits to investigate near surface soil and groundwater conditions and allow recovery of soil samples for testing.
• Soakaway testing within selected trial pits to determine the suitability of soakaways as part of a SUDS for the site.
• Drilling of cable percussive or window sample boreholes to prove sufficient natural strata for founding purposes for the proposed development. To include Standard Penetration Tests (SPTs) in order to provide geotechnical data for the underlying strata.
• Installation of gas and groundwater monitoring wells in selected boreholes.
• Drilling of rotary open boreholes to investigate potential shallow coal workings.
• Chemical and geotechnical laboratory testing to adequately categorise the shallow soils.
• Gas monitoring program (6 visits over 3 months anticipated).
• Reporting.
A pre-demolition asbestos survey will be required prior to any demolition of the existing buildings on site.
Report: C4520 – East Leeds, North Quadrant Prepared for: Persimmon Homes Yorkshire, Mr John Wilson and White Laith