FLOOD RISK ASSESSMENT

GREATFORD,

Report Reference: 2720/FRA Final version F1 December 2019

Report prepared for:

OHL Limited Cricket Pavilion Ashton PE8 5LF

Barkers Chambers  Barker Street  Shrewsbury  United Kingdom  S Y 1 1 S B T : 01743 355770  F: 01743 357771  E : [email protected]

OHL Limited FLOOD RISK ASSESSMENT

GENERAL NOTES

Title of report: Flood Risk Assessment Site: Greatford, Lincolnshire Report ref: 2720/FRA Date: December 2019

Version Date Issued to Draft D1 June 2019 D K Symes Draft D2 November 2019 D K Symes Final F1 December 2019 D K Symes

Author: Katy Rainford BSc Reviewer: Heather MacLeod BSc MSc FGS

This report has been prepared by Hafren Water Ltd for the named Client, with reasonable skill, care and diligence within the agreed scope and terms of contract. Hafren Water Ltd disclaims any responsibility to the client and others in respect of any matters outside the agreed scope of work. This report has been prepared for use by the client and others acting on their behalf. The report may be passed to regulators. This report does not constitute legal advice or opinion.

This report does not represent advice to third parties and no reliance is offered to third parties. No liability is accepted with regard to third parties. Reliance required by any specific Third Party must be agreed in writing with Hafren Water Ltd.

P:\Projects\Greatford\Reports\FRA\Draft\2720-FRA-F1 (Dec 19).docx

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CONTENTS

1 INTRODUCTION ...... 1

Background ...... 1 Data sources ...... 1 National Planning Policy Framework and Planning Practice Guidance ...... 1 Local Policy ...... 2 Regulatory requirement for this assessment ...... 2

2 BASELINE CONDITIONS ...... 3

Location and setting ...... 3 Landform ...... 3 Hydrology ...... 3 2.3.1 Watercourses ...... 3 2.3.2 Waterbodies ...... 4 Flood zones ...... 4 Ground conditions ...... 4 Groundwater levels ...... 5

3 PROPOSED DEVELOPMENT ...... 6

Layout and working scheme ...... 6 Water management ...... 6 3.2.1 Abstraction from clean water ...... 6 3.2.2 Licensing ...... 7 3.2.3 Greenfield run-off ...... 7 Proposed restoration scheme ...... 7

4 APPROACH TO THE FLOOD RISK ASSESSMENT ...... 9

‘Flood risk’ ...... 9 Flood receptors ...... 9 4.2.1 Receptors internal to the Application Area ...... 9 4.2.2 Receptors external to the Application Area ...... 9 Flooding pathways ...... 9

5 FLOOD RISK TO AND FROM THE APPLICATION AREA ...... 11

Fluvial flooding ...... 11 Surface water flooding ...... 11 Groundwater flooding ...... 12 5.3.1 Interaction with Application Area ...... 12 Flooding from sewers and water mains ...... 13

6 FLOOD RISK TO AND FROM THE PROPOSED ACCESS ROAD ...... 14

Fluvial flooding ...... 14 Surface water flooding ...... 14 Interaction with other hydrological components ...... 14

7 SUMMARY AND CONCLUSIONS...... 15

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DRAWINGS

2720/FRA/01 Site location 2720/FRA/02 Surface water features 2720/FRA/03 Fluvial flood risk 2720/FRA/04 Surface water flood risk

APPENDICES

2720/FRA/A1 Site plans 2720/FRA/A2 Greenfield run-off calculations

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1 INTRODUCTION

Background

Planning Permission is being sought to develop a greenfield site near Greatford, Lincolnshire. It is proposed to extract sand and gravel from the site and progressively restore it back to agricultural land with areas designated for nature conservation and an agricultural storage reservoir. The restoration will be achieved using soils only derived from the site. The Application Area, which includes the proposed mineral extraction and processing plant, covers a total area of approximately 55.2 hectares (ha).

Hafren Water has been commissioned by D K Symes Associates Ltd, on behalf of OHL Ltd, to undertake a Flood Risk Assessment (FRA), in support of the Planning Application.

Data sources

The following data sources were used in this assessment:

D K Symes . Site plans

Ordnance Survey (OS) . 1:25,000 scale series mapping

British Geological Survey (BGS) . Geological maps, 1:50,000-scale ( & Wales)

UK Soils Observatory website . Soils map

Environment Agency (EA) . Flood risk maps . Online data sets (http://magic.defra.gov.uk/)

Lincolnshire County Council . Lincolnshire Minerals and Waste Local Plan (adopted June 2016) . Lincolnshire Preliminary Flood Risk Assessment (June 2011)

National Planning Policy Framework and Planning Practice Guidance

This FRA has been undertaken with due regard to the statutory requirements of the National Planning Policy Framework (NPPF) and with reference to the Planning Practice Guidance

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(PPG) in relation to development and flood risk, to ensure that flood risk is taken into account at all stages of the planning process and to avoid inappropriate development in areas potentially at risk of flooding.

PPG classifies the flood risk vulnerability of sites used for sand and gravel extraction as ‘water compatible’, and minerals working and processing as ‘less vulnerable’ development.

Local Policy

Lincolnshire County Council (LCC) is the Lead Local Flood Authority (LLFA) and Mineral Planning Authority (MPA) for the site. LCC’s Minerals and Waste Local Plan (adopted June 2016) includes the Policy DM15 ‘Flooding and Flood Risk’, which states:

“Proposals for minerals and waste developments will need to demonstrate that they can be developed without increasing the risk of flooding both to the site of the proposal and the surrounding area, taking into account all potential sources of flooding and increased risks from climate change induced flooding.

Minerals and waste development proposals should be designed to avoid and wherever possible reduce the risk of flooding both during and following the completion of operations. Development that is likely to create a material increase in the risk of off-site flooding will not be permitted.”

The policy outlined above and the Lincolnshire Preliminary Flood Risk Assessment (PFRA) have been reviewed and this FRA has been compiled in accordance with the relevant objectives.

Regulatory requirement for this assessment

The majority of the Application Area is located within the Environment Agency’s indicative Flood Zone 1, where the probability of fluvial flooding in any one year is less than 1 in 1,000 (Annual Exceedance Probability, AEP <0.1%). A small section within the northeastern extent of the Application Area is located within Flood Zone 2 (1%-0.1% AEP). The Application Area exceeds 1 ha, therefore, a Flood Risk Assessment (FRA) is required in accordance with the Planning Practice Guidance (PPG) and the Environment Agency’s Flood Risk Standing Advice for Local Planning Authorities.

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2 BASELINE CONDITIONS

Location and setting

The Application Area covers approximately 55.2 ha of agricultural land and is located approximately 1.3 km northeast of the centre of Greatford and 1 km southwest of , Lincolnshire. The location of the site is shown on Drawing 2720/FRA/01.

The Application Area comprises a triangular area of land that is bounded by Baston Road to the north and King Street to the east. The southern boundary comprises an unnamed watercourse (as described in Section 2.3.1) with further agricultural fields beyond. The Application Area is centred on National Grid Reference (NGR) TF 102 125 (the nearest postcode is PE9 4PU).

Landform

The Application Area is located on ground which gently decreases in elevation towards the northeast. Ground levels are approximately 10.5 metres Above Ordnance Datum (mAOD) in the southwest declining to approximately 8.5 mAOD in the northeast of the Application Area, towards King Street Drain (see Section 2.3.1).

Hydrology

The locations of the water features discussed in this section are shown on Drawing 2720/FRA/02.

2.3.1 Watercourses

The Application Area lies in the catchment of the River Glen which is located approximately 650 m to the northwest of the Application Area, at its closest reach. Both the East Glen River and the West Glen River converge into the River Glen, approximately 650 m northwest of the Application Area. The River Glen then flows in a general northeasterly direction for approximately 24 km before discharging into the .

The hydrology within the Application Area, and its vicinity, has been heavily modified with numerous drains and ditches. A drain known as King Street Drain runs parallel to King Street along the eastern boundary of the Application Area. This connects to the River Glen approximately 1.7 km north of the Application Area.

Two smaller drains, labelled D1 and D2 on Drawing 2720/FRA/02, exist along the northeastern and southwestern boundaries respectively.

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Two drains, D3 and D4, exist within the Application Area as shown on Drawing 2720/FRA/02. The drain labelled as D3, is sourced 380 m south of the Application Area and flows across it, before connecting with the King Street Drain at the eastern boundary. D4 is located within the southeastern area of the Application Area and flows northwards to drain into D3. These drains were all dry during a site visit on 30th April 2019.

Daily averaged stage and flow measurements were obtained from the Environment Agency for the River Glen at gauge board (Station number 31002). The Kates Bridge gauge board is located approximately 1.7 km north of the Application Area. During the monitoring period (1981 to 2019), a maximum water level of 1.2 m above the gauge datum (6.1 mAOD) was recorded on 6th November 2000, which equates to an elevation of 7.3 mAOD, and corresponds to a flow of 17.7 m/s.

2.3.2 Waterbodies

Eight waterbodies exist within a 1 km radius of the Application Area. A brief description of the waterbodies is given below:

. W1 is a small waterbody located approximately 400 m south of the Application Area. This is regular in shape and is assumed to be a man-made agricultural reservoir . W2 is located approximately 680 m north of the Application Area and is situated 40 m east of the River Glen . W3 is a small waterbody located approximately 820 m southwest of the Application Area, in the eastern extent of Greatford town. This again appears man-made . W4 is located 980 m east of the Application Area and could be an ornamental lake . W5 is a cluster of waterbodies associated with former mineral workings in the area, and is located approximately 850 m to the south-southeast of the Application Area

Flood zones

The Application Area is located predominantly within Flood Zone 1 with only a small area of Flood Zone 2 identified along its northeastern boundary, which is associated with King Street Drain and possibly backwater effects from flood flows in the River Glen. Extracts of the Environment Agency fluvial and surface water flood risk maps are shown on Drawings 2720/FRA/03 and 04.

Ground conditions

The solid geology beneath the Application Area comprises mudstones of the Oxford Clay Formation. The Oxford Clay Formation is classified by the Environment Agency as

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‘Unproductive’; this describes layers of rock with low permeability that have negligible significance for water supply or river baseflow.

This is overlain by the superficial River Terrace deposits which comprise of sand and gravel with local lenses of silt, clay or peat. The River Terrace deposit comprises the economic mineral and is designated by the Environment Agency as a Secondary ‘A’ aquifer; these are permeable layers capable of supporting water supplies at a local rather than strategic scale, and in some cases forming an important source of baseflow to rivers.

According to the Cranfield Soil and Agrifood Institute Soilscapes map, the soil beneath the Application Area is described as ‘freely draining lime-rich loamy’ soils.

Groundwater levels

Groundwater levels are recorded at between approximately 7.2 mAOD in the northeastern extent of the Application Area (borehole B) and approximately 9.8 mAOD in the southwestern corner of the Application Area (borehole I). This compares with ground levels of 8.5 and 10.5 mAOD respectively. Further detail on groundwater levels is included within the hydrogeological report accompanying the Planning Application (2720/HIA, November 2019, Hafren Water).

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3 PROPOSED DEVELOPMENT

Full details of the proposed development are given elsewhere within the Planning Application. However, a brief summary is provided herein for context. A proposed site layout plan is included as Appendix 2720/FRA/A1.

Layout and working scheme

The Application Area will be divided into six broad phases with soil stripping and mineral extraction commencing in the southeastern corner and progressing anti-clockwise around the Application Area. The mineral processing plant will be sited in the south and this will be the final area to be worked. Access will be via a new entrance to be created off King Street towards the south of the Application Area. This will be created by culverting a short section of King Street Drain.

It is estimated that 3 million tonnes of sand and gravel reserves exist at the Application Area, and anticipated output is 0.2 million tonnes per annum.

The mineral will be worked dry, hence dewatering will be required. The dewatered mineral will be removed to the processing plant via excavator and conveyor.

It is currently proposed to temporarily divert the drains (D3 and D4) that cross the Application Area to work the mineral beneath. These will be diverted along the southwestern boundary of the Application Area to Kings Street Drain. Drain D3 will subsequently be reinstated.

Water management

In order to safely extract all the available mineral from the Application Area, it will be necessary to dewater the active working area. Water from the working area will be pumped to the northern end of the silt settlement lagoons which will be formed in the initial extraction phase in the south of the Application Area.

3.2.1 Abstraction from clean water

The mineral processing at the Application Area will include mineral washing. Water for this will be sourced from a clean water lagoon constructed in the far south of the Application Area and south of the settlement lagoons. This lagoon will not be lined and, hence, water will be sourced from the shallow River Terrace sand and gravel aquifer.

Silt-laden water arising from mineral washing will be pumped to the northern end of the silt settlement lagoon. The discharge line will be periodically moved to allow silt to be deposited across the silt settlement lagoons in ‘fan’ style deposits. A high level overflow will exist

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between the settlement lagoons and the clean water lagoon to allow re-circulation of clean water to the processing plant.

Excess water will be pumped from the distal end of the settlement lagoons to Kings Street Drain.

3.2.2 Licensing

It will be necessary to obtain an Environmental Permit for the discharge of excess water to King Street Drain from the Environment Agency. In addition, an abstraction licence will be required for water for use in the processing plant and dust suppression (if needed), and also for the transfer of groundwater from quarry dewatering to King Street Drain.

3.2.3 Greenfield run-off

Peak run-off rates and volumes from the pre-development site, which currently comprises greenfield, have been estimated using the IH124 method (equation 7.1, Institute for

Hydrology Report No 124, 1994). The IH124 method to give mean annual peak flow (QBAR) is of the form:

QBAR(rural) = 0.00108AREA0.89SAAR1.17SOIL2.17

Where: QBAR(rural) mean annual flood, with a return period of 2.3 years (m³/s) AREA catchment area (km²) = 0.552 SAAR (4170) Standard Average Annual Rainfall (1941 to 1970) (mm) = 567 SOIL soil index = 0.4

This method does not account for slope or storm duration and hence provides a conservative estimate of the peak run-off rate. Soils are described as ‘freely draining lime rich loamy’ soils and a SOIL index value (0.4) has been used. The estimate of QBAR(rural) can be used with the UK Flood Studies Report regional growth curves to produce peak flood flows for any return period.

A QBAR(rural) greenfield run-off of 145 l/s has been estimated for the Application Area (Appendix 2720/FRA/A2).

Proposed restoration scheme

It is intended to restore the northern part of the Application Area to low level agriculture. The reinstated drain D3, which currently cuts across the Application Area from the southwestern to eastern boundaries, will form the southern boundary of the low-level agricultural area. South of the drain, the western area will be restored to an agricultural storage reservoir and the eastern part to a nature conservation area.

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The base of the mineral extraction will comprise Oxford Clay and hence will be impermeable. Soils derived from the site will be replaced in the agricultural area and will be graded towards the south and drain D3. The sides of the agricultural area will be progressively lined with Oxford Clay removed from the base of the quarry void concurrent with mineral extraction. This will reduce long-term ingress of groundwater to the low level restoration area. Surface water run-off accumulating in the base of the low level restoration area will collect in the centre of the southern boundary, adjacent to the reinstated drain D3.

From here collected surface water will be pumped to a small pond to the south of drain D3 and from there will flow via gravity to the nature reserve area in the east of the Application Area.

It is proposed to construct an agricultural storage reservoir in the west. Its northwestern banks will be formed by the reinstated drain D3, its southwestern banks comprise the clay-lined cut face of the quarry and the eastern banks will be constructed from clay derived from the base of the quarry void. The clay seals/banks retaining water within the reservoir will be constructed in layers in order to achieve a low permeability as required by the reservoir design.

The nature conservation area will form in the former silt settlement lagoon area. This part of the Application Area will contain silt derived from mineral washing and will be allowed to dry out and naturally colonise.

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4 APPROACH TO THE FLOOD RISK ASSESSMENT

‘Flood risk’

This FRA considers the likelihood of flooding, the associated hazards and the vulnerability of the flood receptor. These factors are combined to produce the single measure, ‘flood risk’.

Flood receptors

4.2.1 Receptors internal to the Application Area

The Application Area is currently used for agricultural purposes. The flood vulnerability of this land use, as defined by PPG, is ‘less vulnerable’.

The proposed operational Application Area will be for sand and gravel extraction, and can therefore be defined as ‘water compatible’.

The PPG does not specifically classify the flood risk vulnerability of access roads, however the development could be classified as ‘transport infrastructure which has to cross the area at risk’, and would therefore be classified as ‘essential infrastructure’.

Post-restoration, the Application Area will be restored to a mixture of low-level agricultural land, a reservoir and wetland areas. These are defined as either ‘water compatible’ or ‘less vulnerable’.

4.2.2 Receptors external to the Application Area

The village of Baston is located to the northeast of the Application Area, with the closest property being approximately 450 m from the Application Area. These residential properties are the closest ones to the Application Area and form ‘highly vulnerable’ receptors within the locality. This level of vulnerability indicates the potential severity of the consequences of flooding of these receptors. The overall degree of flood risk may thus be higher for such receptors for a given severity of flood event.

Other receptors outside the Application Area, comprising roads and agricultural fields are all classed as ‘less vulnerable’.

Flooding pathways

This FRA considers the following hydrological components:

. Fluvial flow . Surface water run-off

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. Groundwater flow . Sewer and/or water mains leakage

Within this FRA, flood risk to both internal and external receptors is assessed with reference to interactions between the quarry and the hydrological components itemised above. For internal receptors this gives information on the degree of flood hazard and hence the degree of flood risk. The potential for the development to qualitatively increase or decrease flood risk at external receptors is assessed so that targeted measures to ensure a qualitative reduction can subsequently be taken, if necessary.

The proposed development to construct an access road over the Kings Street Drain has been considered separately in Section 6.

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5 FLOOD RISK TO AND FROM THE APPLICATION AREA

Fluvial flooding

The majority of the Application Area is located within Flood Zone 1 (<0.1% AEP) with the exception of a small area along the northeastern boundary, as shown on Drawing 2720/FRA/03. This area is located within Flood Zone 2 (1%–0.1% AEP) and is associated with flooding from the King Street Drain.

During operations, all mineral extraction, the plant and processing area (including site offices), and, all soil storage will be located entirely within Flood Zone 1. The overall risk to these areas is therefore considered to be ‘very low’.

The mineral will be dewatered in order to allow its safe and efficient extraction. Excess water generated by this process and not used in mineral washing will be discharged to King Street Drain. The discharge rate will be controlled at the pre-existing greenfield run-off rates (Section 3.2.3) and hence will not increase fluvial flood risk downstream of the site. The necessary flow balancing capacity required on-site allowing for these discharge rates is estimated as 28,876 m³ assuming a 6-hour, 100-year design storm event and allowing for 20% increase in rainfall intensity due to climate change.

The Application Area will be progressively restored to a mixture of low-lying agricultural land, a reservoir and nature conservation area, as described in Section 3.3. These developments will increase the flood storage capacity of the Application Area and therefore reduce the overall flood risk to external receptors in the long-term.

Therefore the overall risk of fluvial flooding to both the internal and external flood receptors is considered ‘very low’ and mitigation measures are not required.

Surface water flooding

Surface water (pluvial) flooding may occur when rainwater does not drain away through the normal drainage systems or percolate to ground, but instead lies on or flows over the ground surface. As such, its occurrence is highly dependent on localised drainage constraints and geology.

The Environment Agency’s ‘Risk of Flooding from Surface Water’ map (Drawing 2720/FRA/04) indicates that there are several small localised areas of ‘low’ risk (0.1–1%) within the Application Area boundary. These are likely to be associated with topographic lows.

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During the operational extraction phase of the development any surface water run-off within the Application Area will be captured by the quarry void. The mineral will be worked dry so therefore dewatering will occur. Water, derived from groundwater and rainfall, will be pumped to silt settlement lagoons and recirculated to a freshwater lagoon located in the south of the Application Area. Any excess water will be discharged off-site to Kings Street Drain. This water management system will remain in place throughout the operational lifetime.

The designed restoration of the Application Area, as described in Section 3.3, is one of low level agriculture and nature conservation together with a sealed irrigation reservoir. Rainfall will, therefore, continue to collect in the base of the Application Area without a natural gravity outfall. Significant flow balancing capacity will exist within the restored Application Area for storage of collected surface water run-off. Collected surface water will be pumped to the conservation area in the east of the site to maintain water levels. It is not intended to provide a long-term discharge from the site to King Street Drain.

The risk to the Application Area from pluvial flooding is considered to be ‘low’, as all the rainfall incident to the Application Area will be collected within its boundaries throughout its lifetime and long-term post-restoration. Impact on surface water flooding to external receptors is, therefore, not expected as a result of the proposed development.

Flood risk posed by site interaction with surface water is not considered significant for any internal or external receptors. As such, mitigation measures are not proposed.

Groundwater flooding

5.3.1 Interaction with Application Area

The permeable sand and gravel will be removed from the Application Area as part of the development and groundwater ingress is expected. The site operations have been designed to accommodate the anticipated volumes. As mineral extraction progresses around the Application Area, low permeability clay from the base will be placed against the sand and gravel quarry faces. This will reduce on-going groundwater ingress to the Application Area and minimise potential for groundwater flooding post-restoration.

Any groundwater ingress will be dewatered out of the quarry void and controlled by the water management system as described in Section 3.2 above. Given the proposed development will utilise water management measures, the flood risk posed by site interaction with groundwater is considered ‘very low’ for any internal or external receptors. Therefore further mitigation measures are not considered necessary.

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Flooding from sewers and water mains

The location of water mains and sewers is not known. Due to the site’s rural location, it is unlikely to interact with flooding from sewers or water mains. However, any potential leakage would discharge into the drains within the vicinity of the Application Area. Utility organisations would subsequently repair the broken pipes. Flood risk posed by site interaction with mains leakage is not considered significant. Therefore further mitigation measures are not considered necessary.

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6 FLOOD RISK TO AND FROM THE PROPOSED ACCESS ROAD

As described in Section 3, the Application Area will require the construction of a new access road which crosses King Street Drain. The drain will be culverted underneath the proposed access road as part of the development. The exact location and working method of the crossing has not yet been determined, however, an indicative flood risk has been provided below. Before works can commence on construction of the crossing a Flood Defence Consent will be required from District Council/Environment Agency.

Fluvial flooding

King Street Drain is designated by the Environment Agency as a main river and is at risk of fluvial flooding. The proposed culvert will be located within Flood Zone 2 (1%–0.1% AEP).

No increase in ground elevation is proposed within the floodplain. The culvert will be designed and constructed to a size that will not impede the 1 in 100-year design event plus an allowance for climate change. Therefore, increased flood risk to internal and external receptors is not anticipated.

Surface water flooding

The culvert has a small footprint and is located away from areas susceptible to surface water flooding. Therefore, its impact on the risk of surface water flooding is very low and mitigation measures are not required.

Interaction with other hydrological components

The degree of flood risk associated with the proposed development’s hydrological interaction with the surrounding area and the internal receptors is not considered significant. Therefore, further mitigation measures are not required.

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7 SUMMARY and CONCLUSIONS

Planning Permission is being sought to develop a greenfield site in Greatford, Lincolnshire. It is proposed to extract sand and gravel with progressive restoration to low level agricultural land as well as create a nature conservation area and a reservoir.

The Application Area covers approximately 55.2 hectares (ha) of agricultural land and is located approximately 1.3 km northeast of Greatford and 800 m south of Baston, Lincolnshire.

The majority of the Application Area is located within Flood Zone 1 (<0.1% AEP) with the exception of a small area in the northeastern extent of the Application Area and along the eastern boundary. This area is located within Flood Zone 2 (1%–0.1% AEP) and is associated with flooding from the King Street Drain.

During operations, all mineral extraction, the plant and processing area (including site offices), and all soil storage will be located entirely within Flood Zone 1. Any surface water run-off within the Application Area will be captured by the quarry void. The mineral will be worked dry so therefore dewatering will occur. Water will be pumped to silt settlement lagoons and recirculated to a freshwater lagoon located in the south of the Application Area. Any excess water will be discharged off-site to Kings Street Drain.

The restoration of the Application Area to a lower level will increase flood storage of the surrounding area and provide additional run-off storage capacity for any surface water flooding, therefore reduce the risk of flooding.

The risk of flooding from fluvial (‘very low’), groundwater (‘very low’), surface water (‘very low’) and sewage/water mains (negligible) has been considered for both internal and external receptors.

A new access road will be required; this will cross the King Street Drain. The drain will be culverted underneath the proposed access road as part of the development.

The risk of flooding from fluvial (‘very low’), groundwater (‘very low’), surface water (‘low’ to ‘very low’) and sewage/water mains (negligible) has been considered for the proposed access road. However further consultation with the Environment Agency will be needed to determine if a flood defence consent or ordinary watercourse consent is required for the proposed work.

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DRAWINGS

December 2019 Version: F1 311000 312000 313000 314000 315000 © Crown copyright Crown © and database 0100031673 Survey Ordnancerights 2019 508000 508000 509000 509000 510000 510000 511000 511000 512000 512000

311000 312000 313000 314000 315000 Date Drawing Project Title Client Barkers Chambers • Street Chambers Barker Barkers • • Shrewsbury www.hafrenwater.com • Tel. 01743 355 770 770 355 01743 • Tel. www.hafrenwater.com Legend 2720/FRA/01 5LF PE8 Peterborough Ashton, Pavilion, Cricket OHLLtd. June 19June Greatford locationSite 1kmbuffer ApplicationArea Shropshire • 1SB Shropshire SY1 Scale correct Scale at A4 Scale Version 1 311000 312000 313000 314000 315000 databaseright and/or Agency Environment information Agency © ContainsEnvironment copyright Crown © and database 0100031673 Survey Ordnancerights 2019

508000 508000 East Glen River Glen East 509000 509000 West Glen River Kates Bridge (31002) Bridge Kates W3

River Glen D2 510000 510000 D3 W1 D1

D4 W2 King Street Drain Street King 511000 511000 W5 512000 512000 W4

311000 312000 313000 314000 315000 Date Drawing Project Title Client Barkers Chambers • Street Chambers Barker Barkers • • Shrewsbury www.hafrenwater.com • Tel. 01743 355 770 770 355 01743 • Tel. www.hafrenwater.com Legend 2720/FRA/02 5LF PE8 Peterborough Ashton, Pavilion, Cricket OHLLtd. June 19June Greatford features water Surface EA gauge board EAgauge (W1 Waterbodies 5) - Watercourse 1kmbuffer ApplicationArea Shropshire • 1SB Shropshire SY1 Scale correct Scale at A4 Scale Version 1 312000 313000 509000 509000 databaseright and/or Agency Environment information Agency © ContainsEnvironment copyright Crown © and database 0100031673 Survey Ordnancerights 2019 510000 510000 511000 511000

312000 313000 Date Drawing Project Title Client Barkers Chambers • Street Chambers Barker Barkers • • Shrewsbury www.hafrenwater.com • Tel. 01743 355 770 770 355 01743 • Tel. www.hafrenwater.com FloodZones Legend 2720/FRA/03 5LF PE8 Peterborough Ashton, Pavilion, Cricket OHLLtd. June 19June Greatford Fluvialflood risk Flood1 zone Flood2 zone Flood3 zone ApplicationArea Shropshire • 1SB Shropshire SY1 Scale correct Scale at A4 Scale Version 1 312000 313000 509000 509000 databaseright and/or Agency Environment information Agency © ContainsEnvironment copyright Crown © and database 0100031673 Survey Ordnancerights 2019 510000 510000 511000 511000

312000 313000 Date Drawing Project Title Client Barkers Chambers • Street Chambers Barker Barkers • • Shrewsbury www.hafrenwater.com • Tel. 01743 355 770 770 355 01743 • Tel. www.hafrenwater.com Surface water floodwater risk Surface Legend 2720/FRA/04 5LF PE8 Peterborough Ashton, Pavilion, Cricket OHLLtd. June 19June Greatford floodwater risk Surface Very low Very risk Lowrisk Mediumrisk risk High ApplicationArea Shropshire • 1SB Shropshire SY1 Scale correct Scale at A4 Scale Version 1 OHL Limited Greatford FLOOD RISK ASSESSMENT

APPENDIX 2720/FRA/A1

Site plans

December 2019 Version: F1 Land at Greatford

To A15 / Thurlby

Public BUND 7 footpath 3m high N

BUND 6 3m high

Existing field access (to be stopped-up) BASTON ROAD BLOCK Note: B KING STREET This is a composite operations plan showing all stages of the development (excavation blocks A-F). For the full consecutive sequence of operations, see the Progressive Operations Plans (1725/PO/1 to 1725/PO/6).

Conveyor (Roman Road) BUND 8 BLOCK BUND 5 (Stages 2-3) 3m high 3m high C Existing track

King Conveyor Street (Stages 1-5) Drain (ditch) BLOCK BLOCK BLOCK E D A BUND 4 Conveyor 4m high (Stage 5 (SILT & WATER MANAGEMENT - if required) FROM STAGE 2 ONWARDS)

BUND 2 4m high BUND 9 3m high

Car parking Ditch removed & PLANT & & fuelling reinstated as part of BLOCK F OPERATIONS area progressive operations AREA PROPOSED Processing ACCESS plant (hard Temporary subsoil store Office, surface) weighbridge (c.4m high) built and & messroom removed progressively Wheel BUND 1 - see Plan Nos 1725/PO/1-6 cleaner Clean 4m high water Site BUND 3 boundary 4m high (red) Temporary Public bridleway To ditch Greatford diversion (Stage 1 to completion) Public footpath

To A16 / West 0m 100m 200m Deeping Contains Ordnance Survey data © Crown copyright and database right 2019. Licence No. 100002373. Version / amendment: 1725/CO/1 v2

D.K. Symes Associates Illustrative Composite Operations Plan Scale - 1:5,000(at A3) Date - 24-09-2019 Plan No. 1725/CO/1

Scale - As shown OHL Limited Greatford FLOOD RISK ASSESSMENT

APPENDIX 2720/FRA/A2

Greenfield run-off calculations

December 2019 Version: F1 Greenfield Runoff Estimate for Pre-Development Area = Discharge Constraint

Parameters Results Area 0.552000 km2 QBAR(rural) 145.2 l/s SAAR 567 Q (1in1yr)* 123.4 l/s SOIL 0.40 FSR region 5 QBAR(rural) 2.6 l/s/ha Return period 2 Q (1in1yr) 2.2 l/s/ha Growth curve factor 0.89 Q (1in100yr) 9.4 l/s/ha

Q (1in1yr)*: approximate calculation using a ratio of 0.85 (R&D Technical Report W5-074/A Preliminary Rainfall Runoff Management For Developments. Revision D - January 2012 )

Return period (yr) 2 5 10 25 50 100 200 Q (l/s/ha) 2.3 3.4 4.3 5.9 7.4 9.4 11.7 Q (l/s) 129.2 187.3 239.5 326.7 410.9 516.8 647.5

Barkers Chambers Client: Barker Street Shrewsbury, Shropshire SY1 1SB UK D K Symes Assoc Ltd Tel: 01743 355770 www.hafrenwater.com

Title: Greenfield run-off rates from pre-development site, using IH124 formula

Project: Greatford Quarry

Calc Sheet: 2720/FRA/A1 Date: Jun-19

P:\Projects\Greatford\Working\Runoff\Runoff calcs 28-06-19/Pre-Dev IH124