ARE UNEXPLODED BOMBS UNDERNEATH SITE OF PROPOSED RIVERHEAD CINEMA?

INTRUSIVE ENGINEERING MAY GENERATE  'SIGNIFICANT RISK' WARNS FIRM

Artist's impression of the proposed development

A SPECIALIST company  has warned that the Riverhead site earmarked for a new cinema/restaurant development could be vulnerable to unexploded ordnance from World War II.

In a report to North East Lincolnshire Council, the expert risk assessment company, 6 Alpha Associates, highlights  the potential hazard  as a result of  disturbance by intrusive works.

It says: “The most probable threat is posed by German high explosive (HE) bombs, while incendiary bombs (IB) and British anti-aircraft artillery projectiles (which were used to defend against German bombing raids) pose a residual threat.

“All types of aggressive intrusive engineering activities may generate a significant risk pathway.”

During the war, the German Luftwaffe undertook bombing campaigns all over the UK.

HE bombs are comparatively “thick-skinned”. If they did not detonate after hitting the ground, the force of impact allowed them to penetrate the ground, leaving behind it an entry hole.

These entry holes were not always apparent, and some went unreported, leaving the bomb buried and unrecorded.

The Nazis’ armoury also included V1 and V2 rockets (thin-skinned, unmanned and inaccurate weapons) and anti-personnel “bomblets”.

Although they had designated primary bombing targets across the UK,  their high altitude night bombing was not accurate.

As a result, thousands of buildings were damaged and civilian fatalities were common.

Bombs were also jettisoned over opportunistic targets, and residential areas were sometimes struck.

During the war, Air Raid Precautions wardens compiled detailed logs of bomb strikes across their respective districts.

ARP records associated with the Grimsby area have not recorded  any HE bomb strikes within the development site, but five were recorded nearby,  the closest being just 40 metres to the west.

Furthermore, two IB landings  were recorded on-site, as well as several others in the vicinity.

Grimsby was subjected to bomb damage in many areas, and Clayton House, which is on the site, was damaged by an  IB strike.

As the threat of invasion lingered over Britain, defensive actions were undertaken.

The British and Allied Forces requisitioned large areas of land for military training and bomb storage (including HE bombs, naval shells, artillery and tank projectiles and other explosives)., 

Thousands of tonnes of these munitions were used for the Allied Forces' weapon testing and military training alone.

It has been estimated that at least 20 per cent of the UK’s land has been used for military training at some point.

It is further  estimated that approximately 10 per cent of all munitions deployed failed to function as designed.

As a result, unexploded wartime ordnance is still   occasionally found whileconstruction and civil engineering groundwork are being undertaken.. 

According to 6 Alpha, in exceptional circumstances, such  ordnance may be  discovered unexpectedly and without apparent rational explanation.

Says the consultancy: "Ways in which this might occur include:

• When Luftwaffe aircraft wished to escape swiftly escape  from an aerial attack, they would jettison some or all of their bombs and flee. This is commonly referred to as tip-and-run and it has resulted in bombs being found in unexpected locations

• Transportation of sediment containing munitions to an area that was previously free of unexploded ordnance usually related to construction activities employing aggregate that may have been dredged from a contaminated offshore borrow area

• Poor precision during targeting (due to high altitude night bombing and/or poor visibility) resulted in bombs landing off target."

Since the war, the centre of Grimsby  has seen extensive demolition and redevelopment, including construction of new roads, so it is likely that most, if not all, unexploded bombs will have been safely accounted for. 

As a precaution, 6 Alpha has recommended that all personnel working on the cinema development site should receive a briefing both on the identification of unexploded ordnance and  what actions they should take to keep people and equipment away from such a hazard.

It says information concerning the nature of the threat should be held in the site office and displayed for general information on notice boards, both for reference and as a reminder for ground workers.

"Safety awareness briefing should be  an essential part of the health and  safety plan for the site," it adds.

6 Alpha Associates itself is able to provide an-on call engineer service in the event of anything dangerous or suspicious being unearthed.

The company, which has offices in Surrey and Suffolk, has extensive expertise across a wide range of projects including assessment and management of  the unexploded ordnance risks associated with offshore windfarm projects, especially where there may be wartime wrecks on the seabed.

On January 18 last year, 6 Alpha staff were  on hand after a  WWII unexploded bomb was removed from the River Thames  Both Waterloo Bridge and Westminster Bridge were shut whilst specialists from the Royal Navy  attempted to recover it.

In May last year, a 6 Alpha team was again on duty when defusal of British bombs took place in the German city of Hanover - some 50,000 residents had to be temporarily evacuated from their homes.

During the war, the city was heavily bombarded, but almost 10 per cent of  some 250,000 bombs that were dropped failed to function properly.