Appendix F

Bactec Preliminary Unexploded Ordnance Risk Assessment, 2013

Bactec Explosive Ordnance Treat Assessment, 2014

Preliminary Unexploded Ordnance Risk Assessment

Project: LINGLEY GREEN AVENUE, WARRINGTON WA5 3LQ Prepared for: Paula Gallagher Client ref: 434387-001

Report prepared by BACTEC International Limited and FIND Mapping Limited Report reference: 500465 Preliminary Unexploded Ordnance Risk Assessment

in respect of LINGLEY GREEN AVENUE, WARRINGTON WA5 3LQ

Contents Page 1. Introduction 2 2. Search Results 4 3. Conclusions 7 4. Risk of UXO based on bombing density 8

This document was written by, belongs to and is copyright to BACTEC International Limited. It contains valuable BACTEC proprietary and confidential information which is disclosed only for the purposes of the client’s assessment and evaluation of the project which is the subject of this report. The contents of this document shall not, in whole or in part (i) be used for any other purposes except such assessment and evaluation of the project; (ii) be relied upon in any way by the person other than the client (iii) be disclosed to any member of the client’s organisation who is not required to know such information nor to any third party individual, organisation or government, or (iv) be copied or stored in any retrieval system nor otherwise be reproduced or transmitted in any form by photocopying or any optical, electronic, mechanical or other means, without prior written consent of the Managing Director, BACTEC International Limited, 9 Waterside Court, Galleon Boulevard, Crossways Business Park, Dartford, Kent, DA2 6NX to whom all requests should be sent. Accordingly, no responsibility or liability is accepted by BACTEC towards any other person in respect of the use of this document or reliance on the information contained within it, except as may be designated by law for any matter outside the scope of this document.

Report prepared by BACTEC International Limited and FIND Mapping Limited Report reference: 500465 1. Introduction Established in 1991, BACTEC International Limited supports the UK construction industry by assessing the risk of encountering items of unexploded ordnance (UXO) during intrusive works. BACTEC’s specialist advice provides essential information for risk assessment, improves safety, enhances reputation and helps contractors to avoid costly delays.

The risk of encountering UXO on most sites in the UK is low. However, where a site is at increased risk it will be necessary to take measures to mitigate that risk. The factors affecting risk assessment are based upon the history and previous usage of a site and its surroundings.

In 2009, the Construction Industry Research and Information Association (CIRIA) established a set of guidelines to assist industry professionals. CIRIA recommends a four stage risk management process:

• Preliminary risk assessment

• Detailed risk assessment

• Risk mitigation

• Implementation

The preliminary risk assessment enables a non-UXO specialist to place a site in context and to identify where a more detailed assessment is necessary. The assessment is based upon data obtained from desktop reviews of the site’s history and its proximity to potential indicators for UXO contamination.

There are two principal sources of UXO risk within the UK:

• Ministry of Defence (MoD) activities

• Bombs and projectiles from WWI and WWII

MoD activities include munitions deposited during training exercises, munitions dumped or disposed of ineffectively, Allied wartime activities, defensive installations etc.

• Abandoned Bombs

• Historic Army Camps

• Army Explosive Ordnance Clearance Tasks/Recces

• Bombing Decoy Sites

• Heavy Anti-Aircraft Batteries

• Military Airfield Sites

Report prepared by BACTEC International Limited and FIND Mapping Limited Report reference: 500465 • Press Articles regarding UXO Finds

• Military Training Areas and Firing Ranges

• BACTEC Desk-top Threat Assessments

• Prisoner of War Camps

• Sites related to the Manufacture of Explosives and Explosive Ordnance

• BACTEC Unexploded Ordnance

• WWII Bombing Density

• WWII Defence Related Positions & Pillboxes

• Pipe Mined WWII Airfields

• Miscellaneous WWII Pipe Mined Locations

• BACTEC On-Site Support Services

Established in 2006, FIND Maps Limited is a pioneering web mapping and spatial data technology company offering online mapping and consultancy services. www.findmaps.co.uk is an excellent example of what FIND can deliver. The portal currently provides detailed mapping and a wealth of data sets to hundreds of the UK’s top property, environmental and design/build companies.

FIND’s consultancy services provide bespoke internet mapping solutions to a range of businesses, enabling them to manage their spatial data more effectively.

While working closely with a wide range of reputable data providers including Ordnance Survey and the Environment Agency, FIND works independently of these organisations. A similar arm’s-length relationship is maintained in terms of software and hardware providers. This enables the team at FIND to offer truly independent advice.

Methodology BACTEC and FIND have compiled a geo-referenced database of potential sources of UXO risk within the UK. From this information a range of risk zones have been defined. The weighting of these zones is based upon the influence of all relevant factors. An airfield, for example, has a far greater zone of influence than a single anti-aircraft battery.

An online preliminary automated UXO risk assessment will determine the potential level of UXO risk relating to a site. The assessment will list all factors contributing to this weighting. Importantly, it will also give appropriate recommendations for further action where this is indicated.

Report prepared by BACTEC International Limited and FIND Mapping Limited Report reference: 500465 2. Search Results Within 10km of the site the following potential sources of explosive ordnance have been recorded:

Number within Source 10km Military Airfield Sites 2 Bombing Decoy Sites 3 Abandoned Bombs 8 WWII Defence Related Positions & Pillboxes 8 Historic Army Camps 3 Prisoner of War Camps 2 Heavy Anti-Aircraft Batteries 4 Army Explosive Ordnance Clearance Tasks/Reccess 9 Sites Related to the Manufacture of Explosives and Explosive Ordnance 5 BACTEC Desk-top Threat Assessments 8 Press Articles regarding UXO Finds None recorded Military Training Areas and Firing Ranges None recorded Pipe Mined WWII Airfields None recorded Miscellaneous WWII Pipe Mined Locations None recorded BACTEC Unexploded Ordnance Finds None recorded BACTEC On-Site Support Services None recorded

Of these sources, the following are deemed significant enough to be a risk and therefore warrant further research:

BACTEC Unexploded Ordnance Finds

Approximate distance (km) Description from site RAF Burtonwood, shell casings recovered 0.2

The defined site is close to an area where BACTEC has previously found and removed items of UXO. This history increases the risk that further munitions may be present.

Report prepared by BACTEC International Limited and FIND Mapping Limited Report reference: 500465 Bombing Decoy Sites

Approximate distance (km) Decoy Type from site RAF Airfield Decoys 1.8

Specially designed decoy sites were constructed during WWII in order to draw Luftwaffe bombers away from more valuable targets. Decoy sites were generally located in open, unpopulated areas. QL sites mimicked urban lighting and Starfish sites featured large strategically shaped fires. Starfish sites were designed to draw incendiary bombs and subsequent high explosive payloads. In 1940 alone, Q and Starfish sites attracted nearly 200 attacks.

Understandably, attacks on decoy sites may not have been well documented. It is therefore difficult to determine whether a particular site was bombed. It is also difficult to determine the extent and accuracy of any confirmed attacks. As the sites were of low importance, clearing them of UXBs was not given high priority. Any intrusive works in an area close to the recorded location of a WWII decoy site may therefore present a higher risk.

Army Explosive Ordnance Clearance Tasks/Reccess

Approximate distance (km) Location from site Raf Burtonwood, Burtonwood, Warrington 0.3 Raf Burtonwood, Burtonwood, Warrington 0.3 Raf Burtonwood, Burtonwood, Warrington 0.3

The site lies within or close to an area where a military clearance operation has been recorded. A clearance operation can describe anything from the recovery of a single item of ordnance found by a member of the public to large scale tasks involving detailed surveys.

Specific research is recommended in order to ascertain the scale of the clearance operation. This would include the type and quantity of ordnance recovered.

Records of a clearance task may indicate a history of military presence in an area. This history increases the risk that further munitions may be present.

Report prepared by BACTEC International Limited and FIND Mapping Limited Report reference: 500465 Military Airfield Sites

Approximate distance (km) Facility Name from site RAF Burtonwood 0.5

The risk of encountering UXO at the site of an airfield is highly dependent upon the history of the site. Factors to be considered include the type of airfield and its role before, during and after WWII. Additional factors affecting the site include records of aerial attacks, test firing butts, bomb stores, remote wooded training areas, practice bomb areas, ammunition storage locations, defensive positions, aircraft crash sites etc.

The 'housekeeping' of such sites, especially those which were active and operational during WWII, was often poor. Experience has shown that on and around many such facilities, ordnance was lost, burnt, buried or otherwise discarded. Live and expended munitions are regularly encountered on such sites.

The proximity of the site to the recorded location of military airfield facilities increases the risk that there may be unexploded ordnance in the area. This should be more fully investigated.

Report prepared by BACTEC International Limited and FIND Mapping Limited Report reference: 500465 3. Conclusions

Risk levels - British unexploded ordnance

High There are significant potential sources of UXO recorded in BACTEC’s historical database in proximity to the site. It is recommended that further research is undertaken to determine more about these sources and to what degree they may have affected the site. Given the proximity and significance of these sources, the risk on site from UXO is considered to be High.

Risk levels – UXB based on bombing density

Low Historical records indicate that the area was subjected to a low level of bombing density. If there is empirical evidence of UXB risk (i.e. anecdotal evidence) then please contact BACTEC for further advice.

This preliminary assessment has identified a Low risk from air-delivered unexploded bombs at this site.

Recommendation - based on highest risk

High This preliminary assessment has resulted in an overall High risk from UXO. BACTEC would recommend that a full Explosive Ordnance Desktop Study is undertaken for this site.

Detailed assessments are conducted offline by BACTEC’s researchers and use information such as historical mapping, WWII-era aerial photography, written air-raid precaution records and where necessary local archive research to fully qualify the risk on site. Land use, changes to building layout during WWII and post war redevelopment will also have an impact on any remaining level of risk from UXO/UXB. It is often possible to ‘zone’ sites into different risk categories. The lead time for a detailed assessment will vary between 3-10 working days dependent upon the complexity of the site and the additional site specific information required.

For a quotation for a detailed UXO threat assessment, or more information, please contact BACTEC on 01322 628178.

Report prepared by BACTEC International Limited and FIND Mapping Limited Report reference: 500465 Risk of UXO based on bombing density LINGLEY GREEN AVENUE, WARRINGTON WA5 3LQ

Crown Copyright 2012. All rights reserved. Licence Number 1000047514 Report reference: 500465 Negligible Low 1:20000 Medium High 0 400 800 Metres

Report prepared by BACTEC International Limited and FIND Mapping Limited Report reference: 500465

Explosive Ordnance Threat Assessment

in respect of

Lingley Green Avenue, Warrington

for

WSP Environment & Energy

5270TA 6th January 2014

BACTEC International Limited 9 Waterside Court, Galleon Boulevard, Crossways Business Park, Dartford, Kent, DA2 6NX Tel: +44 (0)1322284550 Fax: +44 (0)1322628150 Email: [email protected]

www.bactec.com

Registered in England No. 2601923. VAT Registration No. GB 573 6627 13 WSP Environment & Energy Lingley Green Avenue, Warrington

This document was written by, belongs to and is copyright to BACTEC International Limited. It contains valuable BACTEC proprietary and confidential information which is disclosed only for the purposes of the client’s assessment and evaluation of the project which is the subject of this report. The contents of this document shall not, in whole or in part (i) be used for any other purposes except such assessment and evaluation of the project; (ii) be relied upon in any way by the person other than the client (iii) be disclosed to any member of the client’s organisation who is not required to know such information nor to any third party individual, organisation or government, or (iv) be copied or stored in any retrieval system nor otherwise be reproduced or transmitted in any form by photocopying or any optical, electronic, mechanical or other means, without prior written consent of the Managing Director, BACTEC International Limited, 9 Waterside Court, Galleon Boulevard, Crossways Business Park, Dartford, Kent, DA2 6NX, United Kingdom to whom all requests should be sent. Accordingly, no responsibility or liability is accepted by BACTEC towards any other person in respect of the use of this document or reliance on the information contained within it, except as may be designated by law for any matter outside the scope of this document.

Distribution

Copy No. Format Recipient

1 PDF Copy WSP Environment & Energy

2 PDF Copy BACTEC International Limited

Date of Issue: 6th January 2014 Copy no. 1

Originator: OTB

This Report has been produced in compliance with the Construction Industry Research and Information Association guidelines for the preparation of Detailed Risk Assessments in the management of UXO risks in the construction industry.

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Glossary of Terms

AAA Anti-Aircraft Artillery ARP Air-raid Precautions BDO Bomb Disposal Officer EOD Explosive Ordnance Disposal (current term for “bomb” disposal) HE High Explosive HG Home Guard IB Incendiary Bomb kg Kilogram LCC London County Council LM Land Mine LSA Land Service Ammunition (includes grenades, mortars, etc.) Luftwaffe German Air Force m bgl Metres Below Ground Level MoD Ministry of Defence OB Oil Bomb PM Parachute Mine RAF Royal Air Force SI Site Investigation SAA Small Arms Ammunition (small calibre cartridges used in rifles & machine guns) USAAF United States Army Air Force UXB Unexploded Bomb UXO Unexploded Ordnance V-1 “Doodlebug” the first cruise type missile, used against London from June 1944. Also known as ‘Flying Bomb’. V-2 The first ballistic missile, used against London from September 1944 WWI First World War (1914 -1918) WWII Second World War (1939 – 1945)

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Executive Summary

The Site: The site, centred on the approximate OS National Grid Reference: 355898, 390606, is located at the borough boundaries of Warrington and Merseyside. It is bound to the north by the M62 Motorway, to the south by Orion Boulevard, to the west by an agricultural field and to the east by open/undeveloped land.

The site is a large undeveloped area exclusively occupied by unmaintained grass fields, sections of dense vegetation, mature trees, two ponds and dirt tracks. In addition two roundabouts along the southern site boundary have been constructed with planned roadways encroaching into the study area.

Proposed Works: No specific details regarding the type/extent/depth of the proposed intrusive works were available during the production of this report, however it is understood that the study area is to be redeveloped as a manufacturing and distribution site, as part of the Omega South project.

Risk Assessment Methodology: In accordance with CIRIA guidelines this assessment has carried out research, analysed the evidence and considered the risks that the site has been contaminated with unexploded ordnance; that such items remained on site; that they could be encountered during any future works and the consequences that could result. Appropriate risk mitigation measures have been proposed.

Explosive Ordnance Risk Assessment: BACTEC concludes that the site is at Medium risk from UXO. This is based on the following factors:

Allied UXO o The majority of the study area is situated within the historic perimeter of RAF Burtonwood, a WWII/Cold War- era RAF/USAF aircraft maintenance base and US Army Storage Depot. No combat squadrons were ever documented as being stationed on site and therefore the threat from Allied air-delivered ordnance is considered to be low. However previous BACTEC work on several former RAF airfields has resulted in the recovery of a variety of WWII-era UXO, some of which has been inconsistent with the airfield’s operational history. o Although it was located far from the anticipated coastal invasion points, RAF Burtonwood was operational at the start of WWII and therefore it is likely that a degree of defensive preparation was made during the period of expected enemy invasion. It is known that a pillbox was built north of the site and Home Guard (HG) personnel were likely accommodated at the base. Therefore the possibility of weapons and ammunition being stores/used on site cannot be ruled out. o Experience has shown that the ‘house-keeping’ of WWII-era military personnel was often poor with surplus, faulty or expended ordnance often burnt, buried, lost or otherwise discarded in and around military facilities. This is substantiated by UXO finds immediately east of the site in 1983 (250 items) and SAA cartridge finds to the south of the site in 2005. o Operational Log Books for other airfields also describe HG and regular Army units carrying out airfield capture and defence training exercises throughout the war and it is possible that such activity could have resulted in UXO contamination. Similarly it is known that Territorial Army and Cadet training took place at Burtonwood during the 1970s/1980s. o The airfield was defended by anti-aircraft guns which are known to have brought down enemy aircraft during WWII. Therefore the possibility that any unexploded 20mm/40mm shells fell within undeveloped parts of the site and remained undetected, cannot be discounted. o The airbase was used as a US Army storage depot during the Cold War. Although the possibility that munitions were stored in the large aircraft hangars on site during this period cannot be ruled out, the inactive nature of the Cold War suggests the chance of any UXO contamination of the ground as a result of this later occupation is low. German UXO o During WWII the Rural District of Warrington (in which the site was historically located) was an area of low bombing density. The airfield itself was attacked on two separate occasions, however both raids were small- scale and only resulted in a few incendiary bomb strikes; the locations of which are unknown. Furthermore, a 1945 aerial photograph of the RAF station does not exhibit any bomb craters or damage to the buildings on site. o During at least one of the two air raids, it is known that AA defences at the airfield engaged the enemy aircraft and therefore any bombing incidents within the station perimeter will have, at the very least, been observed by these RAF personnel and subsequently investigated. Furthermore, a strike to the numerous buildings on site would have caused obvious observable damage. o However had a UXB fallen unobserved within the western agricultural fields, just outside the airbase perimeter, it may have been ignored by military personnel and furthermore could have remained concealed within the ground cover. Note that the entry hole of an SC50 HE UXB (the most commonly deployed German HE bomb) may have been as small as 20cm in diameter and therefore easily obscured in dense crops or ploughed soil. The site has not been subject to any substantial post-WWII intrusive redevelopment. Furthermore, any RAF/USAF decommissioning work carried out after the closure of the base will likely have been fairly limited, as Burtonwood was never a front line combat base. Therefore the risk from both shallow-buried (Allied) and deep-buried (German)

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UXO is considered to remain across the entire study area. However it should be noted that many WWII-era buildings historically occupied the site and therefore within the volumes of their (now removed) slab foundations, the risk of UXO will be negligible.

It should be noted that although the western portion of the site was located outside the Burtonwood perimeter it is still considered to be at risk due to its proximity to the base. BACTEC has in the past encountered UXO away from, but relatively close to, former military land. Furthermore, the likelihood of German UXBs remaining in this part of the site is slightly higher, however still low.

Bomb Penetration Assessment: It has been assessed that a 500kg bomb would have had a maximum bomb penetration depth of up to 8m below WWII ground level. Penetration depth could potentially have been greater if the UXB was larger (though only 4% of German bombs used in WWII over Britain were of that size). Note that UXBs may be found at any depth between just below the WWII ground level and the maximum penetration depth.

Risk Mitigation Measures: The UXO risk on site is mainly located at shallow depths, therefore the following risk mitigation measures are recommended, prior to the proposed development works: o Explosive Ordnance Safety and Awareness Briefings to all personnel conducting intrusive works. o The provision of Unexploded Ordnance Site Safety Instructions. o Non-Intrusive Magnetometer Survey and target investigation within greenfield areas only. Within areas of hard-standing, made ground, etc a Non-Intrusive Magnetometer Survey is inappropriate due to high levels of background ‘noise’. In these areas the following alternative is recommended: o Explosive Ordnance Disposal (EOD) Engineer presence on site to support shallow intrusive works.

Note that the study area occupies both greenfield and brownfield land and therefore the appropriate risk mitigation measures will vary at different locations within the study area – See Annex S.

Risk Mitigation Map

Brownfield Site – Former airfield. Non-Intrusive Mag Survey and EOD Engineer on-site Support recommended

Greenfield Site - Agricultural fields. Non-Intrusive Mag Survey recommended

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Contents Distribution ...... ii Glossary of Terms ...... iii Executive Summary ...... iv Contents ...... vi Annexes ...... viii 1. Introduction ...... 1 1.1. Background ...... 1 2. Construction Industry Duties and Responsibilities ...... 2 2.1. The UK Regulatory Environment ...... 2 2.2. The Health and Safety at Work Act, 1974 ...... 2 2.3. Construction (Design and Management) Regulations 2007 ...... 2 2.4. Other Legislation ...... 2 3. The Role of the Authorities and Commercial Contractors ...... 2 3.1. The Authorities ...... 2 3.2. Commercial Contractors ...... 3 4. This Report ...... 3 4.1. Aims and Objectives ...... 3 4.2. Risk Assessment Methodology ...... 3 4.3. Approach ...... 3 4.4. Sources of Information ...... 3 4.5. Reliability of Historical Records ...... 4 4.5.1. General Considerations ...... 4 4.5.2. Bombing Records ...... 4 5. The Site ...... 4 5.1. Site Location ...... 4 5.2. Site Description ...... 4 6. Scope of the Proposed Works ...... 5 7. Ground Conditions ...... 5 8. History of RAF Burtonwood ...... 5 8.1. General ...... 5 8.2. RAF Burtonwood Historical Mapping ...... 6 8.3. RAF Burtonwood Historical Aerial Photography...... 6 8.4. Bombing History of Warrington ...... 6 8.4.1. First World War Overview ...... 6 8.4.2. Second World War Overview ...... 6 8.4.3. Second World War Bombing Statistics ...... 7 8.5. Bombing History of RAF Burtonwood ...... 7 8.5.1. Second World War Era Aerial Photography ...... 8 8.5.2. Abandoned Bombs ...... 8 8.5.3. Site Specific Bomb Penetration Considerations ...... 8 8.6. Deductions ...... 8 8.6.1. Density of Bombing ...... 9 8.6.2. Frequency of Access ...... 9 8.6.3. Ground Cover ...... 9 8.6.4. Damage...... 9 8.6.5. Bomb Failure Rate ...... 9 9. The Threat from German Air-Delivered Ordnance ...... 10 9.1. Generic Types of WWII German Air-delivered Ordnance ...... 10 9.2. German Air-delivered Ordnance Failure Rate ...... 10 9.3. UXB Ground Penetration ...... 11

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9.3.1. General Considerations ...... 11 9.3.2. The “j” Curve Effect ...... 11 9.3.3. Second World War Bomb Penetration Studies ...... 11 9.4. Initiation of Unexploded Bombs ...... 11 10. The Threat from Allied Military Ordnance ...... 12 10.1. General ...... 12 10.1.1. Ground Defensive Positions and Home Guard Activity ...... 12 10.1.2. Army Activity ...... 12 10.1.3. Anti-Aircraft Artillery Gun Emplacements ...... 12 10.1.4. Ordnance/Explosives Storage and Disposal ...... 13 10.1.5. Practice Bombing ...... 13 10.1.6. Aircraft Weapons Testing ...... 13 10.1.7. Pipe Mines ...... 14 10.1.8. US Army Depot Activity ...... 14 10.1.9. British Territorial Army and Cadet Training Activities ...... 14 11. Threat Posed By Allied Explosive Ordnance ...... 14 11.1. General ...... 14 11.2. Small Arms Ammunition (SAA) ...... 14 11.3. Land Service Ammunition (LSA) ...... 14 11.3.1. General ...... 14 11.3.2. Mortars ...... 15 11.3.3. Grenades ...... 15 11.4. Miscellaneous ...... 15 11.5. Anti-Aircraft Artillery Shells ...... 15 12. Ordnance Clearance and Post-WWII Ground Works ...... 16 12.1. General ...... 16 12.1.1. EOD Bomb Disposal and Clearance Tasks ...... 16 12.2. Post-War Redevelopment ...... 16 13. The Overall Explosive Ordnance Threat Assessment ...... 16 13.1. General Considerations ...... 16 13.2. The Risk that the Site was Contaminated with Unexploded Ordnance ...... 16 13.3. The Risk that Unexploded Ordnance Remains on Site ...... 17 13.4. The Risk that Ordnance may be Encountered during the Works ...... 17 13.5. The Risk that Ordnance may be Initiated ...... 18 13.6. The Consequences of Encountering or Initiating Ordnance ...... 18 13.7. BACTEC’s Assessment ...... 18 14. Proposed Risk Mitigation Measures ...... 19 14.1. General ...... 19 14.2. Risk Mitigation Measures ...... 19 Bibliography ...... 20

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Annexes

Annex A Site Location Maps

Annex B Recent Aerial Photograph of the Site

Annex C 1945 RAF Burtonwood Station Plan

Annex D 1977 OS Map

Annex E RAF Aerial Photograph – circa 1939

Annex F RAF Aerial Photograph - 1945

Annex G Post-WWII Oblique Aerial Photography

Annex H Luftwaffe Target Maps; Warrington

Annex I Recent German UXB Find – RAF St. Eval

Annex J German Air-Delivered Ordnance

Annex K UXO Press Articles

Annex L Potential Sources of Allied UXO and Additional Features of Interest

Annex M BACTEC UXO Finds at former RAF Moreton-in-Marsh

Annex N Small Arms Ammunition

Annex O Land Service Ammunition

Annex P Miscellaneous Military Contamination

Annex Q Anti-Aircraft Artillery

Annex R 0.303 Cartridges Found at RAF Burntwood - 2005

Annex S Risk Mitigation Map

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Explosive Ordnance Threat Assessment

In Respect of

Lingley Green Avenue, Warrington

1. Introduction

1.1. Background

WSP Environment & Energy has commissioned BACTEC International Limited to conduct an Explosive Ordnance Threat Assessment for the construction works at the Lingley Green Avenue site, Warrington, Cheshire.

The site occupies part of the former WWII/Cold War-era airfield, RAF Burtonwood. Unexploded Ordnance (UXO) presents a significant threat to construction projects in parts of the UK as a result of enemy actions during the two 20th Century world wars and historic British and Allied military activity. On sites formerly used by the military the potential for Allied operations to have left a legacy of explosive ordnance contamination is especially high.

Another legacy of WWII is buried unexploded German air-dropped bombs or (British) anti- aircraft projectiles, resulting from the failure of a proportion of these weapons to function as designed. It is commonly accepted that the failure rate of these munitions was approximately 10% and, depending on their shape, weight, velocity and ground conditions, many penetrated the ground and came to rest at depth. Intensive efforts were made during and after the war to locate and render safe all UXO but, unsurprisingly, not all were found and dealt with.

The UK was also bombed during WWI, though to a much lesser extent, and it is thought that a similar proportion of these weapons also malfunctioned. There have been occasional finds of unexploded WWI bombs in recent years but the risk of encountering them today is generally very low.

As a result of generally increased risk awareness amongst professionals involved in ground engineering works and proactive health and safety measures, the threat to life and limb from UXO has been minimised. However even the simple discovery of a suspected device during on- going works can cause considerable disruption to production and cause unwanted delays and expense.

Such risks can be more fully controlled by a better understanding of the site-specific threat and the implementation of appropriate risk mitigation measures.

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2. Construction Industry Duties and Responsibilities

2.1. The UK Regulatory Environment

There is no specific legislation covering the management and control of the UXO risk in the UK construction industry but issues regarding health and safety are addressed under a number of regulatory instruments, as outlined below.

In practice the regulations impose a responsibility on the construction industry to ensure that they discharge their obligations to protect those engaged in ground-intrusive operations (such as archaeology, site investigation, drilling, piling or excavations) from any reasonably foreseeable UXO risk.

2.2. The Health and Safety at Work Act, 1974

The Act places a duty of care on an employer to put in place safe systems of work to address, as far as is reasonably practicable, all risks (to employees and the general public) that are reasonably foreseeable.

2.3. Construction (Design and Management) Regulations 2007

This legislation defines the responsibilities of all parties (primarily the Client, the CDM Co- ordinator, the Designer and the Principal Contractor) involved with works.

Although UXO issues are not specifically addressed the regulations effectively place obligations on all these parties to: o Ensure that any potential UXO risk is properly assessed. o Put in place appropriate risk mitigation measures if necessary. o Keep all parties affected by the risk fully informed. o Prepare a suitably robust emergency response plan.

2.4. Other Legislation

Other relevant legislation includes the “Management of Health and Safety at Work Regulations 1999” and “The Corporate Manslaughter and Corporate Homicide Act 2007”.

3. The Role of the Authorities and Commercial Contractors

3.1. The Authorities

The Police have the responsibilities for co-ordinating the emergency services in the case of an ordnance-related incident on a construction site. They will make an initial assessment (i.e. is there a risk that the find is ordnance or not?) and if they judge necessary impose a safety cordon and/or evacuation and call the military authorities (JSEODOC - Joint Services Explosive Ordnance Disposal Operations Centre) to arrange for investigation and/or disposal. In the absence of an EOD specialist on site many Police Officers will use the precautionary principle, impose cordon(s)/evacuation and await advice from the JSEODOC.

The priority given to the request by JSEODOC will depend on their judgement of the nature of the threat (ordnance, location, people and assets at risk) and the availability of resources. They may respond immediately or as resources are freed up. Depending on the on-site risk assessment the item of ordnance may be removed or demolished (by controlled explosion) in- situ. In the latter case additional cordons and/or evacuations may be necessary.

Note that the military authorities will only carry out further investigations or clearances in very high profile or high risk situations. If there are regular ordnance finds on a site the JSEODOC may not treat each occurrence as an emergency and will encourage the construction company to put in place alternative procedures (i.e the appointment of a commercial contractor) to manage the situation and relieve pressure from the JSEODOC.

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3.2. Commercial Contractors

In addition to pre-construction site surveys and clearances a commercial contractor is able to provide a reactive service on construction sites. The presence of a qualified EOD Engineer with ordnance recognition skills will avoid unnecessary call-outs to the authorities and the Contractor will be able to arrange for the removal and disposal of low risk ordnance. If high risk ordnance is discovered actions will be co-ordinated with the authorities with the objective of causing the minimum possible disruption to site operations whilst putting immediate, safe and appropriate measures in place.

4. This Report

4.1. Aims and Objectives

The aim of this report is to examine the possibility of encountering any explosive ordnance during the proposed works at the Lingley Green Avenue site. Risk mitigation measures will be recommended, if deemed necessary, to reduce the threat from explosive ordnance during the envisaged works. The report follows the CIRIA Guidelines.

4.2. Risk Assessment Methodology

The following issues will be addressed in the report:

o The risk that the site was contaminated with unexploded ordnance. o The risk that unexploded ordnance remains on site. o The risk that ordnance may be encountered during any future works. o The risk that ordnance may be initiated. o The consequences of initiating or encountering ordnance. Risk mitigation measures, appropriate to the assessed level of risk and site conditions, will be recommended if required.

4.3. Approach

In preparing this Explosive Ordnance Threat Assessment Report, BACTEC has considered general and, as far as possible, site specific factors including:

o Evidence of German bombing and delivery of UXBs. o Site history, occupancy and conditions during WWII. o The legacy of Allied military activity. o Details of any known EOD clearance activity. o The extent of any post war redevelopment. o Scope of the current proposed works.

4.4. Sources of Information

BACTEC has carried out detailed historical research for this Explosive Ordnance Threat Assessment including accessing military records and archived material held in the public domain and in the MoD.

Material from the following sources has been consulted: o The National Archives, Kew. o RAF Museum, Hendon. o www.ukaerialphotos.com. o Relevant information supplied by WSP Environment & Energy. o Available material from 33 Engineer Regiment (EOD) Archive.

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o BACTEC’s extensive archives built up over many years of research and hands-on Explosive Ordnance Disposal activities in the UK. o Open sources such as published books, local historical records and the internet.

4.5. Reliability of Historical Records

4.5.1. General Considerations

This report is based upon research of historical evidence. Whilst every effort has been made to locate all relevant material BACTEC cannot be held responsible for any changes to the assessed level of risk or risk mitigation measures based on documentation or other information that may come to light at a later date.

The accuracy and comprehensiveness of wartime records is frequently difficult or impossible to verify. As a result conclusions as to the exact location, quantity and nature of the ordnance threat can never be definitive but must be based on the accumulation and careful analysis of all accessible evidence. BACTEC cannot be held responsible for inaccuracies or gaps in the available historical information.

4.5.2. Bombing Records

During WWII considerable efforts were expended in recording enemy air raids. Air Raid Precautions (ARP) wardens were responsible for making records of bomb strikes either through direct observation or by post-raid surveys. However their immediate priority was to deal with casualties and limit damage, so it is to be expected that records are often incomplete and sometimes contradictory. Record keeping in the early days of bombing was not comprehensive and details of bombing in the early part of the war were sometimes destroyed in subsequent attacks. Some reports may cover a single attack, others a period of months or the entire war.

Records of raids that took place on sparsely or uninhabited areas were often based upon third party or hearsay information and are not always reliable; records of attacks on military or strategic targets were often maintained separately from the general records and have not always survived.

5. The Site

5.1. Site Location

The site is located at the borough boundaries of Warrington and Merseyside. It is bound to the north by the M62 Motorway, to the south by Orion Boulevard, to the west by an agricultural field and to the east by open/undeveloped land.

The site is centred on the approximate OS National Grid Reference: 355898, 390606

Site location maps are presented in Annex A.

5.2. Site Description

The site is a large undeveloped area exclusively occupied by unmaintained grass fields, sections of dense vegetation, mature trees, two ponds and dirt tracks. In addition two roundabouts along the southern site boundary have been constructed with planned roadways encroaching into the study area.

The site is located within the historical boundary of RAF Burtonwood, a WWII-era military base. In late 2008/early 2009 the remaining buildings (large storage hangers north of the study area) were demolished over a four-month period. Some of the WWII aircraft hardstands, part of the old airfield perimeter track, and the northwest end of a secondary runway exist, however it is understood that the study area has been cleared of all structures and almost all concreted areas.

A recent aerial photograph showing the boundary of the site area is presented in Annex B.

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6. Scope of the Proposed Works

No specific details regarding the type/extent/depth of the proposed intrusive works were available during the production of this report, however it is understood that the study area is to be redeveloped as a manufacturing and distribution site, as part of the Omega South project.

7. Ground Conditions

Site specific BGS borehole data lists the following geological sequence under the study area: 2.9m of Made Ground (soft to stiff sandy gravelly clay with sandstone cobbles), underlain by at least 9.6m of superficial Glacial Till deposits (very stiff sandy gravelly clay), underlain by Sherwood Sandstone (very dense red weathered Sandstone bedrock) to depth.

8. History of RAF Burtonwood

8.1. General

RAF Burtonwood opened as an Aircraft Repair Depot (ASU) on the 1st April 1940, with No.37 Maintenance unit (MU) being the first unit to be stationed at the site. ASUs were tasked with storage, modification and repair and so the main occupation of the facility during WWII was to receive new aircraft in their basic form (from factories across the UK) before modifying them for their unique roles. This would involve the fitting of weapons and additional specialised equipment such as radar, radios, lights, etc, prior to eventual delivery to their operational units.

Burtonwood was the biggest airbase in Europe during WWII with 18,500 personnel working at the facility during its peak. These men and women were accommodated in 1,045 Nissen and Gerrard Huts across five dispersed sites. During one particularly busy month, a total of 1,019 aircraft were modified, assembled or repaired. In June 1942 the USAAF took over Burtonwood, however it continued in its role as an ASU but for the US’s Eighth, Ninth, Twelfth and Fifteenth Air Forces.

After the war, thousands of surplus US aircraft were scrapped at Burtonwood before the Americans finally left in 1946. With the end of hostilities control of the base was returned to the RAF and it became an equipment depot operated by No.276 MU. In 1948 the USAF used Burtonwood again during the Berlin Airlift and later as a base for supplying US Strategic Air Command units across Europe.

In November 1953 the USAF 53rd Weather Reconnaissance Squadron began operating from the base and also during the 1950s, European-based USAF aircraft were overhauled or modified at Burtonwood.

Major USAF use of the facility ended in April 1959 when the flightline was closed. For several years the airfield fell into disuse and then in 1965 the USAF finally returned the station to the MoD. However US forces returned to Burtonwood in 1966 when France withdrew its military support for NATO. The base was used as a receiving depot for USAF and US Army equipment and supplies being withdrawn from their former French NATO facilities. Afterwards, the US Army took over and renamed it Burtonwood Army Depot.

The US Army then developed the facility into a storage and forward supply depot operated by the 47th Support Group. The main warehouse was described as the largest building under a single roof in Europe. In the event of an emergency, US troops in the USA that were earmarked for NATO service in Europe would arrive at Burtonwood and collect their equipment before flying on to the battle front. Although it was never tested for this eventuality, the base did provide relief supplies for the Bosnian war in 1990 and finally in 1991 its remaining equipment went to the Middle East, to supply the US Army during The Gulf War.

With the end of the Cold War, Burtonwood was declared surplus to NATO requirements and was closed in June 1994.

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In addition to US Army activity, the 1970s and 1980s also saw the area extensively used by Territorial Army and Cadet units for training purposes. Burtonwood was also used by the MoD for civil contingency and emergency planning exercises, as well as EOD exercises for Police and Fire & Rescue training.

8.2. RAF Burtonwood Historical Mapping

A 1945 RAF Station plan for Burtonwood was obtained from the RAF Museum and is presented in Annex C. The accompanying legend for the plan is not known to exist and therefore it has not been possible to identify any of the buildings/structures on site. Note however that the large cluster of parallel buildings within the study area is labeled Lythgoe Site, which is known to have been an accommodation area. The plan shows that the study area also includes aircraft hangers, dispersal pans and buildings from the Technical Site (immediately east). The western portion of the site is shown to fall outside the perimeter of the base.

A 1977 OS map showing the majority of the study area is presented in Annex D. This plan suggests that the accommodation blocks on site have been demolished and removed – Camp Site (Disused). In addition the large warehouses that lined the southern boundary of the site have gone and the two aircraft dispersal pans near the northern boundary are in the process of being broken up.

8.3. RAF Burtonwood Historical Aerial Photography

A low resolution aerial photograph of the base (circa 1939) is presented in Annex E. This image shows the airfield during the latter stages of construction. The study area is still partially occupied by agricultural fields, however two large hangars, part of what appears to be the technical site, and a runway taxiway have been constructed on site. Note that the former main runway has been since used to form part of the M62 motorway.

The image presented in Annex F is a high resolution shot taken in the final year of WWII. It shows the study area as it appears on the 1945 Burtonwood Station Plan, with the majority of the area occupied by numerous structures and hard-surfaced access roads. The south-western portion of the site is occupied by open fields, outside the airbase perimeter.

The accommodation blocks (Nissen and Gerrard Huts) are interspersed by green space and there are also some narrow sections of denser vegetation (with mature trees). Note that the pale areas of open ground associated with the northern runway and the three aircraft hangars are patches of bare earth. Also noteworthy is the large quantities of equipment/stores stockpiled next to these three hangars.

Two oblique photographs exhibiting portions of the study area are presented in Annex G. The first image (dated circa 1946), shows the eastern extent of the study area in the early post- WWII period. It confirms the continued development of the site, however also highlights the quantity of open ground within this part of the site. The second photograph (circa 1960s) shows the south-western corner of the site. It is occupied by the three vast hangars and the remains of a former accommodation site. The rows of hard-standings, where barrack blocks used to stand, are now visible.

8.4. Bombing History of Warrington

8.4.1. First World War Overview

Although the UK was bombed by Zeppelin airships and Gotha fixed wing bombers during WWI, Warrington is known to have evaded attacks from either aircraft and therefore no threat from WWI German UXO exists.

8.4.2. Second World War Overview

During late 1940 the Luftwaffe planned to destroy key military installations, including RAF airfields and Royal Navy bases, during a series of daylight bombing raids in south and eastern England. After the Battle of Britain these tactics were modified to include both economic and industrial sites across the entire country. Targets included dock facilities, railway infrastructure, power stations, weapon manufacturing plants and gas works. As a result of aircraft losses, daylight raids were reduced in favour of attacking targets under the cover of darkness.

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As the war progressed the strategy changed to one of attempting to destroy the morale of the civilian population by the “carpet bombing” of London and other cities such as Liverpool and Manchester. This period became known as The Blitz and lasted till the end of May 1941 when the majority of the Luftwaffe was diverted east to prepare for ‘Operation Barbarossa’; the invasion of the Soviet Union.

A Luftwaffe reconnaissance map for Warrington is presented in Annex H. This map indicates that the Luftwaffe were aware of many of Warrington’s wartime industries, even though it was never the subject of a specific large-scale Blitz type raid, like those seen in neighbouring Manchester and Liverpool.

It is known however that the town was attacked and as it was located on a Luftwaffe flight- path to Manchester and it is possible that due to poor navigating and harassment by Allied air defences, the wider Warrington area may have sustained additional bombing due to ‘tip and run’ incidents1.

Records of bombing incidents in civilian areas were collected by the Air Raid Precautions wardens and collated by the Civil Defence Office. However RAF bases maintained separate records and those original records for RAF Burtonwood were unavailable within the timeframe of this report.

8.4.3. Second World War Bombing Statistics

The following table summarises the quantity of German bombs (excluding 1kg incendiaries and anti-personnel bombs) falling on the Rural and Urban Districts of Warrington between 1940 and 1945. Note that the site lies close to the border of these two districts.

Record of German Ordnance Dropped on The Rural and Urban Districts of Warrington

District Urban Rural Area Acreage 4,413 22,457 High Explosive Bombs (all types) 18 100 Parachute Mines 2 4 Oil Bombs 2 2 Phosphorus Bombs 0 0 Pilotless Aircraft (V1) 0 0 Fire Pot 0 0 Long Range Rocket (V2) 0 0 Total 22 106 Items Per 1,000 Acres 5.0 4.7

Source: Home Office Records

Detailed records of the quantity and locations of the 1kg incendiary and anti-personnel bombs were not routinely maintained by the authorities as they were frequently too numerous to record. Although the incendiaries are not particularly significant in the threat they pose, they nevertheless are items of ordnance that were designed to cause damage and inflict injury and should not be overlooked in assessing the general risk to personnel and equipment. The anti- personnel bombs were used in much smaller quantities and are rarely found today but are potentially more dangerous.

This table does not include UXO found during or after WWII.

8.5. Bombing History of RAF Burtonwood

The sheer size of Burtonwood made the base a tempting and easily identifiable target for German bombers. However despite Luftwaffe reconnaissance flights over the airfield, it was

1 Some bombers approaching target cities could not reach their objectives due to anti-aircraft fire or fighter interception and would jettison their bombs indiscriminately before returning to base.

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only bombed on two occasions, with little damage. Burtonwood was laid out in such a way that if one section was bombed, work could continue in another area.

A detailed history of RAF Burtonwood2 records one single air raid on the station during WWII. On 27th September 1940 two bombers flew low over the airfield and dropped several incendiaries near the runways, to little effect. Both aircraft were subsequently shot down by Burtonwood’s AA batteries. Note that no information relating to the apparent second attack could be found.

8.5.1. Second World War Era Aerial Photography

The previously discussed 1945 aerial photograph was taken immediately following the cessation of Luftwaffe bombing over Britain. No evidence of bombing (destroyed buildings or craters in open ground) is apparent.

8.5.2. Abandoned Bombs

A post-air raid survey of buildings, facilities and installations would have included a search for evidence of bomb entry holes. If evidence were encountered, Bomb Disposal Officer teams would normally have been requested to attempt to locate, render safe and dispose of the bomb. Occasionally evidence of UXBs was discovered but due to a relatively benign position, access problems or a shortage of resources the UXB could not be exposed and rendered safe. Such an incident may have been recorded and noted as an Abandoned Bomb.

Given the inaccuracy of WWII records and the fact that these bombs were ‘abandoned’, their locations cannot be considered definitive, nor the lists exhaustive. The MoD states that ‘action to make the devices safe would be taken only if it was thought they were unstable’. It should be noted that other than the ‘officially’ abandoned bombs, there will inevitably be UXBs that were never recorded.

BACTEC holds no records of officially registered abandoned bombs on or near the site.

8.5.3. Site Specific Bomb Penetration Considerations

When considering an assessment of the bomb penetration at the proposed site the following parameters would be used:

o Geology – 2.9m of Made Ground (soft to stiff sandy gravelly clay with sandstone cobbles), underlain by at least 9.6m of superficial Glacial Till deposits (very stiff sandy gravelly clay), underlain by Sherwood Sandstone (very dense red weathered Sandstone bedrock) to depth o Impact Angle and Velocity – 80-90O from horizontal and 267 metres per second. o Bomb Mass and Configuration – The 500kg SC (General Purpose) HE bomb, without retarder units or armour piercing nose. This was the largest of the common bombs used against Britain.

Taking into account the above-mentioned factors it has been assessed that a 500kg bomb would have had a maximum bomb penetration depth of up to 8m below WWII ground level. Penetration depth could potentially have been greater if the UXB was larger (though only 4% of German bombs used in WWII over Britain were of that size). Note that UXBs may be found at any depth between just below the WWII ground level and the maximum penetration depth.

8.6. Deductions

Utilising the available historical bombing records as reviewed in Section 8, it is possible to make an assessment of the likelihood that evidence of unexploded German air-delivered ordnance would have been noted on a site during the war and the incident dealt with or recorded at the time. Factors such as bombing density, frequency of access, ground cover, damage and failure rate have been taken into consideration.

2 C. Ashworth, Action Stations – Military Airfields of Wales & The North-West, 1985

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8.6.1. Density of Bombing

Bombing density is an important consideration for assessing the possibility that UXBs remain in an area. A very high density of bombs can for example result in increased levels of damage sustained to structures, greater likelihood of errors in record keeping and a higher risk that UXBs fell over the area.

The site was located within an area of low bombing density during WWII, with only two small scale raids recorded over the airbase. The precise locations of the bomb strikes are unknown and therefore the possibility that munitions fell within the site boundary cannot be ruled out.

8.6.2. Frequency of Access

Unexploded ordnance at sites where human access was infrequent would have a higher chance of being overlooked than at those sites which were subject to greater occupancy. The importance of a site or facility to the war effort is also an important consideration as such sites are likely to have been both frequently accessed and are also likely to have been subject to post-raid checks for evidence of UXO.

Levels of access will have been variable across different parts of the airfield. The developed parts of the site will have been regularly accessed, however peripheral parts of this area as well as the northern runway/taxiway portion and south-western agricultural fields will have been accessed to a lesser degree.

During the recorded air raid, it is known that AA defences at the airfield engaged the enemy aircraft and therefore any bombing incidents within the station perimeter will have been observed, investigated and well documented. Note however BACTEC recently encountered an unexploded German 50kg HE bomb (see Annex I) at the site of the former RAF St. Eval airfield in Cornwall, highlighting the possibility that such incidents could have remained undetected at military facilities.

8.6.3. Ground Cover

The degree and type of groundcover present during WWII would have a significant effect on the visual evidence at ground level which may have indicated the presence of buried UXO.

Parts of the study area were occupied by rough grassland, bare earth and farmed fields. In these locations it is conceivable that an observed UXB strike could have remained undetected. Note that the entry hole of an SC50 HE UXB (the most commonly deployed German HE bomb) may have been as little as 20cm in diameter and therefore easily obscured in vegetation. A UXB strike to the buildings and hard-surfaced taxiways/roads however will have caused obvious damage which will have been dealt with at the time.

8.6.4. Damage

If structures on a site have been subject to significant bomb or fire damage rubble and debris are likely to have been present; similarly a HE bomb strike on open ground is likely to have resulted in a degree of soil disturbance. Under such conditions there is a greater risk of the entry holes of unexploded bombs dropped during subsequent raids being obscured and going unnoticed.

WWII-era RAF aerial photography does not exhibit any obvious damage to the airfield buildings or bomb craters in open ground. Note however that craters in open ground could be temporary features, in-filled and repaired prior to the available photography.

8.6.5. Bomb Failure Rate

There is no evidence to suggest that the bomb failure rate in the vicinity of the site would have been different from the “approximately 10%” figure normally used.

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9. The Threat from German Air-Delivered Ordnance

9.1. Generic Types of WWII German Air-delivered Ordnance

The nature and characteristics of the ordnance used by the Luftwaffe allows an informed assessment of the hazards posed by any unexploded items that may remain today. Detailed illustrations of German air delivered ordnance are presented at Annex J.

o HE Bombs: In terms of weight of ordnance dropped, HE bombs were the most frequent weapon deployed. Most bombs were 50kg, 250kg or 500kg (overall weight, about half of which was the HE) though large bombs of up to 2,000kg were also used. HE bombs had the weight, velocity and shape to easily penetrate the ground intact if they failed to explode. Post-raid surveys would not always have spotted the entry hole or other indications that a bomb penetrated the ground and failed to explode and contemporary ARP documents describe the danger of assuming that damage, actually caused by a large UXB, was due to an exploded 50kg bomb. Unexploded HE bombs therefore present the greatest risk to present–day intrusive works. o Blast Bombs/Parachute Mines: Blast bombs generally had a slow rate of descent and were extremely unlikely to have penetrated the ground. Non-retarded mines would have shattered on most ground types, if they had failed to explode. There have been extreme cases when these items have been found unexploded, but this was where the ground was either very soft or where standing water had reduced the impact. BACTEC does not consider there to be a significant threat from this type of munition on land. o Large incendiary bombs: This type of bomb ranged in size from 36kg to 255kg and had a number of inflammable fill materials (including oil and white phosphorus), and a small explosive charge. They were designed to explode and burn close to the surface but their shape and weight meant that they did have penetration capability. If they penetrated the ground complete combustion did not always occur and in such cases they remain a risk to intrusive works. o 1kg Incendiary Bombs (IB): These bombs, which were jettisoned from air-dropped containers, were unlikely to penetrate the ground and in urban areas would usually have been located in post-raid surveys. However, if bombs did not initiate and fell in water or dense vegetation, or became mixed with rubble in bomb damaged areas they could have been overlooked. Some variants had explosive heads and these present a risk of detonation during intrusive works. o Anti-personnel (AP) Bomblets: AP bombs had little ground penetration ability and should have been located by the post-raid survey unless they fell into water, dense vegetation or bomb rubble. o Specialist Bombs (smoke, flare, etc): These types do not contain HE and therefore a detonation consequence is unlikely. They were not designed to penetrate the ground.

9.2. German Air-delivered Ordnance Failure Rate

Based on empirical evidence, it is generally accepted that 10% of the German HE bombs dropped during WWII failed to explode as designed. This estimate is probably based on the statistics of wartime recovered UXBs and therefore will not have taken account of the unknown numbers of UXBs that were not recorded at the time, and is probably an underestimate.

The reasons for failures include:

o Fuze or gaine malfunction due to manufacturing fault, sabotage (by forced labour) or faulty installation. o Clockwork mechanism failure in delayed action bombs. o Failure of the bomber aircraft to arm the bombs (charge the electrical condensers which supplied the energy to initiate the detonation sequence) due to human error or equipment defect. o Jettison of the bomb before it was armed or from a very low altitude. Most likely if the bomber was under attack or crashing.

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War Office Statistics document that a daily average of 84 bombs which failed to function were dropped on civilian targets in Great Britain between 21st September 1940 and 5th July 1941. 1 in 12 of these (probably mostly fitted with time delay fuzes) exploded sometime after they fell - the remainder were unintentional failures.

From 1940 to 1945 bomb disposal teams dealt with a total of 50,000 explosive items of 50kg and over (i.e. German bombs), 7,000 AAA shells and 300,000 beach mines. These operations resulted in the deaths of 394 officers and men. However, unexploded ordnance is still regularly encountered across the UK (see recent press articles, Annex K-1).

9.3. UXB Ground Penetration

9.3.1. General Considerations

The actual penetration depth of aerial delivered bombs into the ground will have been determined by the mass and shape of the bomb, the velocity and angle of the bomb on impact (dependent on the height of release) and the nature of the ground and ground cover; the softer the ground, the greater the potential penetration. Peat, alluvium and soft clays are easier to penetrate than gravel and sand. Bombs are brought to rest or are commonly deflected by bedrock or large boulders.

9.3.2. The “j” Curve Effect

An air-dropped bomb falling from normal bombing altitude (say 5,000m) into homogeneous ground will continue its line of flight but turn in an upwards curve towards the surface as it comes to rest. This offset from vertical is generally thought to be about one third of the penetration depth, but can be up to 15m depending on ground conditions or the bomb’s angle of impact.

9.3.3. Second World War Bomb Penetration Studies

During WWII the Ministry of Home Security undertook a major study on actual bomb penetration depths, carrying out statistical analysis on the measured depths of 1,328 bombs as reported by Bomb Disposal, mostly in the London area. They then came to conclusions as to the likely average and maximum depths of penetration of different sized bombs in different geological strata.

The median penetration of 430 x 50kg German bombs in London Clay was 4.6m and the maximum penetration observed for the SC50 bomb was 9m.

They concluded that the largest common German bomb, 500kg, had a likely penetration depth of 6m in sand or gravel but 8.7m in clay. The maximum observed depth for a 500kg bomb was 10.2m and for a 1,000kg bomb 12.7m. Theoretical calculations suggested that significantly greater penetration depths were probable.

9.4. Initiation of Unexploded Bombs

Unexploded bombs do not spontaneously explode. All HE requires significant energy to create the conditions for detonation to occur. In the case of unexploded German bombs discovered within the construction site environment, there are a number of potential initiation mechanisms:

o Direct impact onto the main body of the bomb: Unless the fuze or fuze pocket is struck, there needs to be a significant impact (e.g. from piling or large and violent mechanical excavation) to initiate a buried iron bomb. Such violent action can cause the bomb to detonate. o Re-starting the clock timer in the fuze: Only a small proportion of German WWII bombs employed clockwork fuzes. It is probable that significant corrosion has taken place within the fuze mechanism over the last 60 years that would prevent clockwork mechanisms from functioning, nevertheless it was reported that the fuze in a UXB dealt with by 33 EOD Regiment in Surrey in 2002 did re-commence. o Induction of a static charge, causing a current in an electric fuze: The majority of German WWII bombs employed electric fuzes. It is probable that significant corrosion has taken

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place within the fuze mechanism over the last 60 years such that the fuze circuit could not be activated. o Friction impact initiating the (shock-sensitive) fuze explosive: This is the most likely scenario resulting in the bomb detonating. Annex K-2 details UXB incidents where intrusive works have caused UXBs to detonate, resulting in death or injury and damage to plant.

10. The Threat from Allied Military Ordnance

10.1. General

RAF Burtonwood was in use as a military base from 1940-1994. Throughout its operational period no front line combat squadrons were ever stationed at Burtonwood, however as with any former military base, the possibility of UXO contamination can never be entirely ruled out.

It should be noted that due to the frequency and intensity of operations, coupled with a generally more relaxed attitude towards matters of health and safety, items of UXO were more likely to be misplaced or buried during WWII. This is evidenced by the regularity of WWII-era UXO finds on former MoD property by the public and the construction industry. Although Burtonwood was also in use as a military base for the remainder of the 20th Century, it is unlikely that any modern UXO will have contaminated the site.

The following is a list of the potential sources/activities that could have led to UXO contamination at RAF Burtonwood during WWII.

10.1.1. Ground Defensive Positions and Home Guard Activity

RAF airfields constructed immediately prior to the outbreak of war were typically fortified by pillboxes, defence huts, weapons pits etc. Pillboxes would have been of a brick or concrete construction and faced either away from the airfield for outer defence or towards the airfield for inner defence. During the period when the threat of enemy invasion was high (1940-41), these positions would have been manned by armed Home Guard personnel.

Information taken from the English Heritage’s study of the WWII anti-invasion landscape of England (mapping the locations and types of WWII-era defences around the country), records one such position at the airfield as well as a Hamilton Pickett Fort (a type of retractable pillbox) see Annex L. The lack of significant defences is likely due to Warrington’s north- westerly location, which meant that it was not vulnerable to an initial German attack.

The Home Guard (HG) was a defence organisation of the British Army, operational between 1940 and 1944. It comprised 1.5 million local volunteers, otherwise ineligible for military service, and acted as a secondary defence force, in case of enemy invasion. The HG guarded the vulnerable coastal areas of Britain and other important facilities such as airfields, factories and explosives stores.

Although Burtonwood did not require a large defence force, HG personnel would have been stationed on site with the responsibility of guarding the base. They would have been issued with LSA/SAA and any localised weapons training may have involved live ammunition.

10.1.2. Army Activity

The operational log books of other WWII-era RAF airfields indicate that British bases like Burtonwood were occasionally used in 1943 and 1944 by British and Commonwealth Army units for enemy airfield capture training, ahead of the 1944 D-Day landings. It is known that such activities involved live munitions and pyrotechnics and therefore the possibility of UXO contamination within the airfield perimeter during any such training cannot be ruled out.

10.1.3. Anti-Aircraft Artillery Gun Emplacements

At the start of WWII two types of AAA guns were deployed: Heavy Anti-Aircraft Artillery (HAA), using large calibre weapons such as the 3.7” QF (Quick Firing) gun and Light Anti- Aircraft Artillery (LAA) using smaller calibre weapons such as 40mm Bofors gun. All RAF

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airfields were defended by light anti-aircraft batteries which were usually dispersed around the airfield in isolated positions.

LAA shells were high explosive (HE) projectiles, fitted with a contact fuze to make them explode on impact. If these shells failed to strike an aircraft, they would eventually fall back to earth.

With LAA guns firing 120 rounds/min, airfield batteries could expend many shells in even short engagements and therefore due to the vegetated nature of parts of the site, the possibility of AA projectile contamination cannot be ruled out. This type of ordnance is not likely to have had great penetration ability, and the majority of unexploded AAA shells are found close to WWII ground level or in made ground.

10.1.4. Ordnance/Explosives Storage and Disposal

During WWII a range of ordnance would have been stored on site. Broadly speaking this would have included:

o LSA and SAA - issued to airfield security personnel/Home Guard.

o Light Anti-Aircraft Projectiles – issued to the airfield AA regiment.

o .303” aircraft machine gun ammunition – handled by RAF ground crews.

Mapping confirms that the station did not have an isolated/bunded bomb dump and therefore the risk from British air-delivered HE/incendiary bombs is considered minimal.

The site did however contain some aircraft dispersal pans. On combat operational airfields it is known that these features are where planes would be loaded with ammunition and bombs prior to a mission. It is known that aircraft were routinely fitted with their machine guns/cannons at Burtonwood, however it is likely that ammunition was only fed in once they were delivered to their operational Fighter/Bomber Command bases.

Anecdotal accounts suggest that at WWII air stations, faulty, surplus or spent ordnance would often be burnt (in designate burning pits), buried or otherwise disposed of within peripheral/unused parts of the base, or in the immediate surrounding area. This is evidenced by the discovery, by BACTEC, of various items of UXO at former WWII-era RAF airfields, such as RAF Biggin Hill, RAF Eastchurch, RAF Dyce and RAF Moreton-in-Marsh.

The latter of which was a Bomber Command OTU station utilising Wellington bombers. At this station BACTEC recently encountered many items of UXO within the ‘between runway’ grass areas – see Annex M - similar to the northern and eastern extents of the study area. Although the type and quantity of ordnance/munitions at Burtonwood will have been much less, this annotated aerial photograph illustrates how UXO contamination could occur in various (apparently random) places at WWII-era airfields.

It should also be noted that although the site was occupied by numerous accommodation blocks, there is still the possibility of associated UXO contamination. It is known that during decommissioning operations at the Rowcroft Barracks in Ashford, a grenade was found in an accommodation block drain pipe and at the Church Crookham Barracks near Fleet a search and clear dog team sent into a disused barracks building also discovered a grenade.

10.1.5. Practice Bombing

Although weapons were fitted to aircraft at Burtonwood, it is considered unlikely that bomb release mechanisms would have required full ‘flight conditions’ testing from altitude at the airbase. Aircraft mechanics based at the combat operational RAF stations will have been responsible for servicing aircraft and therefore would have repaired any routine problems with their aircraft.

10.1.6. Aircraft Weapons Testing

WWII airfields generally had firing ranges, test butts (sand bags) and other similar measures in place to test aircraft machine guns/cannons. Potential contamination in these areas would include live rounds, other munitions and heavy metals such as lead, antimony and barium.

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The lack of legend for the 1945 station plan means it is impossible to identify the location of the testing facilities at Burtonwood.

10.1.7. Pipe Mines

Pipe mines were deployed under the runways and significant buildings of some of the RAF airfields during the early part of WWII and were designed to destroy these installations in the event of invasion. Although the airfield was operational during the period of possible invasion, BACTEC’s database does not list RAF Burtonwood as one of the facilities that was mined.

10.1.8. US Army Depot Activity

In 1967 the US Army were looking for a location to be used as a Reserve Storage Activity site and so RAF Burtonwood entered the last and longest phase in its history. The base was used for the storage of every item of equipment used by the US Army in Europe, including 10 x 1,000 bed mobile surgical hospitals, 19,000 parachutes, 750,000 meals, thousands of vehicles, spares, small arms and many more stores.

An anecdotal account states that when the Americans left Burtonwood, they didn't take all the vehicles and equipment back with them. It is suggested that there are Jeeps and other vehicles buried 30 ft down under what is now Chapelford Urban Village (1km south-east of the site), the new housing estate built on the former Air Base land. Other equipment was simply burned, scrapped or dumped in the sea. Although it is thought that the bulk of the American Army Depot was actually located to the south-east of the study area, the indication that equipment was buried highlights the possibility of similar activities throughout the entire airbase.

10.1.9. British Territorial Army and Cadet Training Activities

Although it is known that Burtonwood was used by the British Army during the 1970s/1980s for Territorial Army and Cadet training purposes, this activity is unlikely to have resulted in significant quantities of UXO on site. Any contamination relating to this training will likely be SAA or pyrotechnics (flares, smoke grenades, etc). Note however the former airbase covered a vast area and therefore it is likely that these may not have even taken place within the study area.

11. Threat Posed By Allied Explosive Ordnance

11.1. General

Although the airfield was fairly limited in terms of its operational activities, there is still considered to have been a variety of ordnance used on site. The most likely items of UXO to be encountered are listed below.

11.2. Small Arms Ammunition (SAA)

The most likely type of ordnance to be encountered on site are items of SAA (bullets), used on RAF aircraft machine guns/canons, AA Lewis guns and HG rifles/machine guns. Even if an item such as this functioned however, the explosion would not be contained within a barrel and detonation would only result in local overpressure and very minor fragmentation from the cartridge case. Images of SAA are presented in Annex N.

11.3. Land Service Ammunition (LSA)

11.3.1. General

The term Land Service Ammunition covers all items of ordnance that are propelled, placed or thrown during land warfare. They may be filled or charged with explosives, smoke, incendiary or pyrotechnics. They can be broken into five main groups:

a. Mortars b. Grenades

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c. Projectiles d. Rockets e. Landmines Unexploded or partially unexploded Mortars and Grenades are among the most common items of UXO encountered in the UK and therefore the possibility cannot be discounted that they were stores on site. They are commonly encountered in areas used by the military for training and are often found discarded on or near historic military bases. Examples of Grenades, Mortars and Home Guard weapons are presented in Annex O.

Items of ordnance do not become inert or lose their effectiveness with age. Time can indeed cause items to become more sensitive and less stable. This applies equally to items submerged in water or embedded in silts, clays or similar materials. The greatest risk occurs when an item of ordnance is struck or interfered with. This is likely to occur when mechanical equipment is used or when unqualified personnel pick up munitions.

11.3.2. Mortars

A mortar bomb is a fin-stabilised munition, normally nose-fuzed and fitted with its own propelling charge (primary cartridge). Range is increased by adding extra propellant (augmenting charges). They are either HE or Carrier and generally identified by their tear- dropped shape (older variants however are parallel sided) and a finned ‘spigot tube’ screwed or welded to the rear end of the body housing the propellant charge. A mortar relies on a striker hitting a detonator for explosion to occur. It is possible that the striker may already be in contact with the detonator and that only a slight increase in pressure would be required for initiation. Discarded augmenting charges are often encountered around mortar firing areas/bases.

11.3.3. Grenades

A grenade is a short range weapon which may be thrown by hand, fired from the end of a rifle or projected/propelled from a special purpose grenade launcher. They are divided into two categories; HE and Carrier (generally smoke). As with mortars, a grenade striker may either be in contact with the detonator or still be retained by a spring under tension, and therefore shock may cause it to function. A grenade can have an explosive range of 15-20m. Common older variants have a classic ‘pineapple’ shape; modern grenades tend to be smooth-sided.

11.4. Miscellaneous

When working on land used currently or historically by the military, all manner of explosive ordnance related items dating back over 100 years could be encountered. These may include practice (dummy) items, experimental weapons and other miscellanea such as pyrotechnics/flares for use in battle simulation training exercises. Images of the most commonly encountered miscellaneous items are presented in Annex P.

11.5. Anti-Aircraft Artillery Shells

These shells are frequently mistakenly identified as small German air-delivered bombs, but are differentiated by the copper driving band found in front of the base. Although the larger unexploded projectiles could enter the ground they did not have great penetration ability and are therefore likely to be found close to WWII ground level. With a HE fill and fragmentation hazard these items of UXO also present a significant risk if encountered. The smaller 40mm projectiles are similar in appearance and effect to small arms ammunition and, although still dangerous, present a lower risk. Pictures of AAA projectiles are presented in Annex Q. Details of the most commonly deployed WWII AAA projectiles are shown below:

Gun type Calibre Shell Weight Shell Dimensions

3.7 Inch 94mm 12.7kg 94mm x 438mm 4.5 Inch 114mm 24.7kg 114mm x 578mm 40mm 40mm 0.9kg 40mm x 311mm

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12. Ordnance Clearance and Post-WWII Ground Works

12.1. General

The extent to which any ordnance clearance activities have taken place on site or extensive ground works have occurred is relevant since on the one hand they may indicate previous ordnance contamination, but also may have reduced the risk that ordnance remains undiscovered.

12.1.1. EOD Bomb Disposal and Clearance Tasks

It was standard procedure for RAF EOD personnel to carry out a decommissioning EOC task following the closure of a military airfield. Recent UXO discoveries on other former bases however highlight the fact that these were not one hundred percent clearances and an anecdotal account from a former RAF EOD engineer confirms that only the bomb stores and dispersal pan areas were usually searched and surveyed prior to sale of the land.

BACTEC holds a number of official records of explosive ordnance disposal operations during and following WWII, obtained from the Explosive Ordnance Disposal (EOD) Archive Information Office at 33 Engineer Regiment (EOD). The database records an EOC Task carried out in 1983, during which 250 items of expended UXO were found just east of the study area. No further details regarding these finds however were available.

In addition BACTEC was contacted in 2005 by a construction company carrying out works at the former RAF Burtonwood site. This was with regards to a single UXO find that turned out to be two inert 0.303 cartridge cases (see Annex R). Although these are not dangerous items of UXO they do hihlghit the possibility of additional contamination in the area. The find was made at the southern end of the former RAF Burtonwood site where the MoD had previously sold the real estate, issuing a clearance certificate in respect of explosive ordnance.

12.2. Post-War Redevelopment

The site has not been subject to any significant redevelopment in the post-war period.

13. The Overall Explosive Ordnance Threat Assessment

13.1. General Considerations

Taking into account the quality of the historical evidence, the assessment of the overall threat to the proposed works from unexploded ordnance must evaluate the following risks: o That the site was contaminated with unexploded ordnance o That unexploded ordnance remains on site o That such items will be encountered during the proposed works o That ordnance may be activated by the works operations o The consequences of encountering or initiating ordnance

13.2. The Risk that the Site was Contaminated with Unexploded Ordnance

For the reasons discussed in Sections 8 and 10 BACTEC believes that there is a risk from encountering explosive ordnance at the Lingley Green Avenue site. These reasons are summarised below.

Allied UXO o The majority of the study area is situated within the historic perimeter of RAF Burtonwood, a WWII/Cold War-era RAF/USAF aircraft maintenance base and US Army Storage Depot. No combat squadrons were ever stationed on site and therefore the threat from Allied air-delivered ordnance is considered to be low. However previous BACTEC work on several former RAF airfields has resulted in the recovery of a variety of WWII-era UXO, some of which has been inconsistent with the airfield’s operational history.

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o Although it was located far from the anticipated invasion beaches, RAF Burtonwood was operational at the start of WWII and therefore it is likely that a degree of defensive preparation was made during the period of expected enemy invasion. It is known that a pillbox was built north of the site and Home Guard (HG) personnel were likely accommodated at the base. Therefore the possibility of weapons and ammunition being stores/used on site cannot be ruled out. o Experience has shown that the ‘house-keeping’ of military personnel was often poor with surplus, faulty or expended ordnance often burnt, buried, lost or otherwise discarded in and around military facilities. This is substantiated by UXO finds immediately east of the site in 1983 (250 items) and SAA cartridge finds to the south of the site in 2005. o Operational Log Books for other airfields also describe HG and regular Army units carrying out airfield capture and defence training exercises throughout the war and it is possible that such activity could have resulted in UXO contamination. Similarly it is known that Territorial Army and Cadet training took place at Burtonwood during the 1970s/1980s. o RAF Burtonwood was defended by anti-aircraft guns which are known to have brought down enemy aircraft during WWII. Therefore the possibility that any unexploded 20mm/40mm shells fell within undeveloped parts of the site and remained undetected, cannot be discounted. o Burtonwood was used as a US Army storage depot during the Cold War. Although the possibility that munitions were stored in the large aircraft hangars on site during this period cannot be ruled out, the inactive nature of the Cold War suggests the chance of any UXO contamination of the ground is low. German UXO o During WWII the Rural District of Warrington (in which the site was historically located) was an area of low bombing density. The airfield itself was attacked on two separate occasions, however both raids were small-scale and only resulted in a few incendiary bomb strikes; the locations of which are unknown. Furthermore, a 1945 aerial photograph of the RAF station does not exhibit any bomb craters or damage to the buildings on site. o During at least one of the two air raids, it is known that AA defences at the airfield engaged the enemy aircraft and therefore any bombing incidents within the station perimeter will have, at the very least, been observed by these RAF personnel and subsequently investigated. Furthermore, a strike to the numerous buildings on site would have caused obvious observable damage. o However had a UXB fallen unobserved within the western agricultural fields, just outside the airbase perimeter, it may have been ignored by military personnel and furthermore could have remained concealed within the ground cover anyway. Note that the entry hole of an SC50 HE UXB (the most commonly deployed German HE bomb) may have been as small as 20cm in diameter and therefore easily obscured in dense crops or ploughed soil.

13.3. The Risk that Unexploded Ordnance Remains on Site

The site has not been subject to any substantial post-WWII intrusive redevelopment. Furthermore, any RAF/USAF decommissioning work carried out after the closure of the base will likely have been fairly limited, as Burtonwood was never a front line combat base. Therefore the risk from both shallow-buried (Allied) and deep-buried (German) UXO is considered to remain across the entire study area. However it should be noted that many WWII-era buildings historically occupied the site and therefore within the volumes of their (now removed) slab foundations, the risk of UXO will be negligible.

13.4. The Risk that Ordnance may be Encountered during the Works

The most likely scenarios under which a UXO could be encountered during the proposed construction works is during excavations for cabling or shallow foundations and any locations which may be selected for piling. The overall risk will depend on the extent of any future works, such as the numbers of boreholes/piles (if required) and the volume of the excavations.

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An air-dropped bomb may come to rest at any depth between just below ground level and its maximum penetration depth so there is also a chance that such an item could be encountered during shallow excavations (for services or site investigations) into the original WWII ground level. However, at this site the bulk of the risk will lie at shallow depths.

13.5. The Risk that Ordnance may be Initiated

The risk that UXO could be initiated if encountered will depend on its condition, how it is found and the energy with which it is struck. The most violent activity on most construction sites is percussive piling; however UXO may initiate on impact with any heavy machinery.

13.6. The Consequences of Encountering or Initiating Ordnance

Clearly the consequences of an inadvertent detonation of UXO during construction operations would be catastrophic with a serious risk to life, damage to plant and a total site shutdown during follow-up investigations.

Since the risk of initiating ordnance is comparatively low if appropriate mitigation measures are undertaken, the most important consequence of the discovery of ordnance will be economic. This would be particularly so in the case of high profile locations and could involve the evacuation of the public. The unexpected discovery of ordnance may require the closing of the site for any time between a few hours and a week with a potentially significant cost in lost time. Note also that the suspected find of ordnance, if handled solely through the authorities, may also involve loss of production since the first action of the Police in most cases will be to isolate the locale whilst awaiting military assistance, even if this turns out to have been unnecessary.

13.7. BACTEC’s Assessment

Taking into consideration the findings of the study, BACTEC considers the risk across the study area to be Medium.

It should be noted that although the western portion of the site was located outside the Burtonwood perimeter it is still considered to be at risk due to its proximity to the base. BACTEC has in the past encountered UXO away from, but relatively close to, former military land. Furthermore, the likelihood of German UXBs remaining in this part of the site is slightly higher, however still low.

Level of Risk

Type of Ordnance Negligible Low Medium High

Allied Air-Delivered Ordnance *

Allied Land Service and Small Arms * Ammunition

British Anti-Aircraft Projectiles *

German HE/Incendiary UXBs *

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14. Proposed Risk Mitigation Measures

14.1. General

The UXO risk on site is mainly located at shallow depths, therefore the following risk mitigation measures are recommended, prior to the proposed development works. Note that the study area occupies both greenfield and brownfield land and therefore the appropriate risk mitigation measures will vary at different locations within the study area; see Risk Mitigation Map presented in Annex S.

14.2. Risk Mitigation Measures

o Explosive Ordnance Safety and Awareness Briefings to all personnel conducting intrusive works: A specialised briefing is always advisable when there is a possibility of explosive ordnance contamination. It is an essential component of the Health & Safety Plan for the site and conforms to requirements of CDM Regulations 2007. All personnel working on the site should be instructed on the identification of UXB, actions to be taken to alert site management and to keep people and equipment away from the hazard. Posters and information of a general nature on the UXB threat should be held in the site office for reference and as a reminder. o The provision of Unexploded Ordnance Site Safety Instructions: These written instructions contain information detailing actions to be taken in the event that unexploded ordnance is discovered. They are to be retained on site and will both assist in making a preliminary assessment of a suspect object and provide guidance on the immediate steps to be taken in the event that ordnance is believed to have been found. o On greenfield areas only: Non-Intrusive Magnetometer Survey and target investigation: This survey is carried out using caesium vapour magnetometers linked to a data logger. Data is interpreted using advanced proprietary software which is capable of modelling the magnetic anomalies for mass, depth and location, thus providing information which can be used to locate discrete buried objects that may be ordnance. The system will typically locate buried ordnance to a depth of 4m for a 50kg bomb (the smallest HE bomb used by the Luftwaffe) and deeper for larger bombs. Additionally the survey will locate any buried services with a magnetic signature, will indicate areas of gross magnetic “contamination” (which may indicate unknown underground obstructions) and provide information on archaeological features. The technique is not appropriate in a brownfield or built environment; where such a technique is not appropriate, an EOD engineer presence on site is recommended. In areas of hard-standing, made ground, etc a Non-Intrusive Magnetometer Survey is inappropriate due to high levels of background ‘noise’. In these locations the following alternative is recommended: o Explosive Ordnance Disposal (EOD) Engineer presence on site to support shallow intrusive works: When on site the role of the EOD Engineer would include; monitoring works using visual recognition and instrumentation and immediate response to reports of suspicious objects or suspected items of ordnance that have been recovered by the ground workers on site; providing Explosive Ordnance Safety and Awareness briefings to any staff that have not received them earlier and advise staff of the need to modify working practices to take account of the ordnance threat, and finally to aid Incident Management which would involve liaison with the local authorities and Police should ordnance be identified and present an explosive hazard.

BACTEC International Limited 6th January 2014

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Bibliography

The key published documents consulted during this assessment are listed below:

o Bowyer, M, J, F., Action Stations 7: Military Airfields of Wales & The North-West, Patrick Stephens Publishing. 1983. o Falconer, J., RAF Bomber Airfields of World War 2, Ian Allan Publishing. 1992. o Dobinson, C., AA Command: Britain’s Anti-Aircraft Defences of the Second World War, Methuen. 2001. o Fegan, T., The Baby Killers’: German Air raids on Britain in the First World War, Leo Cooper Ltd. 2002. o Fleischer, W., German Air-Dropped Weapons to 1945, Midland Publishing. 2004. o Jappy, M. J., Danger UXB: The Remarkable Story of the Disposal of Unexploded Bombs during the Second World War. Channel 4 Books, 2001. o Osborne, M., 20th Century Defences in Britain. The East Midlands. Concrete Publications. 2003. o Price, A., Blitz on Britain, The Bomber Attacks on the United Kingdom 1939 – 1945, Purnell Book Services Ltd. 1977. o Ramsey, W., The Blitz Then and Now, Volume 1, Battle of Britain Prints International Limited. 1987. o Ramsey, W., The Blitz Then and Now, Volume 2, Battle of Britain Prints International Limited. 1988. o Ramsey, W., The Blitz Then and Now, Volume 3, Battle of Britain Prints International Limited. 1990. o Whiting, C., Britain Under Fire: The Bombing of Britain’s Cities 1940-1945, Pen & Sword Books Ltd. 1999.

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