A gaping hole on one of the busiest routes into Plymouth has been cordoned indefinitely after fears more hidden grenades could be buried there.


Last week the council said the latest discovery of 14 more phosphorous grenades meant the decision was taken to suspend excavation works on Tavistock Road.

Now the area has been fenced off, and it has not yet been confirmed when work might start again.

The fencing has been installed around the excavated section near Derriford Roundabout, where multiple Self-Igniting Phosphorus (SIP) grenades were dug up last week.

The emergency services, the bomb squad, contractors and public transport services are currently working to decide the best way forward, the council said in a statement last week.

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There might be more buried there

Some work on the multi million pound Derriford Transport Scheme will carry on around the site where the devices have been found.

In a joint statement, the council and the police said: “Public safety and the safety of workers on site has to be our primary concern but we recognise the huge impact that closing one of the city’s arterial routes has on the community and the travelling public.

“With the potential for more of these devices to be found the decision has been made to suspend all excavation work until we agree the best steps to identify any further devices and manage their safe removal to allow these essential works to continue.

“The council will agree a plan jointly with its contractor, the police, explosive ordnance experts and partners, including the emergency services.

“We appreciate the public’s patience during these unexpected incidents and will issue an update as soon as possible.

“In the meantime arrangements are being made to secure and monitor the site and under no circumstances must anyone attempt to access the excavated area.”

A survey was previously carried out as part of the pre-construction assessments, which identified the potential for finding unexploded ordnance in the area.

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There are many theories as to why they are there

They added that this information fed into the construction plans and risk assessments, with “appropriate control and mitigation measures put in place”.

The statement was made by Anthony Payne, the council’s strategic director for place, and Chief Supt Andy Boulting, Plymouth’s Police Commander.

A spokesman for the Royal Navy’s Explosive Ordnance Disposal (EOD) team said the latest batch of phosphorous grenades, discovered on Thursday, were considered to be “more secure and stable” than ones found earlier this week.

As a result they were removed by the EOD team and taken to an undisclosed location to be destroyed.


The full joint statement from Plymouth City Council and Devon and Cornwall Police

UXO

Plymouth City Council has suspended excavation work for the Derriford Transport Scheme following the discovery of more white phosphorus grenades on Tavistock Road today.

Ten World War Two grenades were found on Tuesday afternoon and controlled detonations were carried out by the Royal Navy’s Explosive Ordnance Disposal (EOD) team. A further 14 grenades were found and removed today.

Public safety and the safety of workers on site has to be our primary concern but we recognise the huge impact that closing one of the city’s arterial routes has on the community and the travelling public.

With the potential for more of these devices to be found the decision has been made to suspend all excavation work until we agree the best steps to identify any further devices and manage their safe removal to allow these essential works to continue.

The council will agree a plan jointly with its contractor, the police, explosive ordnance experts and partners, including the emergency services.

We appreciate the public’s patience during these unexpected incidents and will issue an update as soon as possible. In the meantime arrangements are being made to secure and monitor the site and under no circumstances must anyone attempt to access the excavated area.


Why are the grenades there?

Such finds remain common in the UK*, with the often haphazard munitions disposal practices of the Home Guard coming back to bite some 75 years later.

This grenade was only issued to the Home Guard, a defence organisation of the British Army during the Second World War.

A SIP grenade was basically a glass bottle, much like a milk bottle, filled with a combination of phosphorous and benzine.

When broken the phosphorous ignites the benzine on exposure to the air. When the bomb squad was called back to Tavistock Road on Wednesday to “puffs of white smoke”, it was leftover phosphorous reacting with chemicals in the air.

– Plymouth Herald