What are the financial implications of not conducting EOD clearance in a known area of UXO contamination within the project scope?

Despite the possibility of an inadvertent detonation of an item of UXO that has remained in a “dormant state”, over an extended period of time, this may be seen to by planners as “low risk”. However, the presence of an item of UXO at a work site, can still have significant financial implications.

The potential of UXO risks not being managed by a suitable EOD specialist or contractor, could lead to  delays to the construction project schedule and an associated increase in project costs.

With the development of untouched areas (brownfield sites) that have historical UXO contamination potential,  or where limited “shallow” development has taken place, the risk of encountering or uncovering UXO during the groundwork phase of the project, is significantly increased.

Who are EROWTEC Limited and its affiliate SGS UK Ltd attracting as clients ?

It is our intention to raise the awareness of the dangers of UXO with the decision makers responsible for project planning within the construction industry and related fields. These include, local authorities, regulators, insurers policy makers, developers, consultants, contractors, civil engineers. geotechnical investigation and remediation professionals associated with construction projects.

EROWTEC Limited security specialists will be looking to provide services to all industry sectors. These include, corporate, private and all commercial fields.

In planning EOD / UXO risk management, what responsibilities apply to and are expected of the different parties involved in a construction project?

The following was taken from an article published by the Federation of Piling Specialists.

Clients – Are to supply any information that is relevant to the risks presented by a project. If there is a potential risk of UXO contamination, they are required to seek guidance from and to engage an EOD Specialist / qualified advisor

(The Client’s responsibilities under CDM cannot be transferred.)

CDM Coordinator – provides the Client with a key project advisor in respect of construction health and safety risk management matters, including UXO risk. What is a CDM coordinator? (Construction, Design and Monitor)

The appointment of the CDM coordinator does not remove the Client’s responsibilities with regard to health and safety.

The Designer –

  • Responsible for identifying and eliminating hazards and reducing risks in so far as this is reasonably practicable.
  • Must supply adequate information regarding the design and any unusual or hidden risks.
  • Must communicate risk information in an appropriate manner and in an appropriate timescale so that other parties involved in the works are aware of any residual risks that were not eliminated by the design process to enable them to act upon the information as required.

In the case of UXO, those responsible for undertaking the initial site, selection the UXO risk assessment and for designing the risk mitigation plan (including the design of any site works) will all be considered as Designers under CDM.

Principal Contractor –

Responsible for preparing the Construction Phase Plan and with overall responsibility for health and safety during the construction works. They:

  • Must ensure the potential risks from encountering UXO have been suitably addressed including the possible risks to off-site receptors.
  • Are also responsible for ensuring any construction phase UXO risk mitigation requirements (including emergency plans) are implemented correctly. If a UXO risk assessment identifies the potential for UXO to be encountered on a site, and this risk cannot be mitigated, the Principal Contractor must prepare a suitably robust emergency response plan that details the procedures to be followed in the event of UXO being encountered during the works.
  • Must have sufficient appropriately trained staff on site at all times to ensure the effective implementation of the emergency response plan.
  • Must ensure that adequate arrangements have been made with the public emergency services to enable them to respond in an appropriately manner to any potential UXO incident.

Contractors (Including Piling and Ground Improvement Contractors) –

  • Must provide the Principal Contractor with any information relating to their work that might affect health and safety. This will include information relevant to any changes in site practices or site conditions that may impact on potential risk from UXO. They must also comply with directions from the Principal Contractor.


“Work should not start on sites where a UXO hazard has been identified until an emergency response plan is in place.”


“All employers with employees working on or visiting a site at which there is a reasonably foreseeable risk from UXO therefore have a statutory duty to ensure, so far as is reasonably practicable, that a safe system of work is in place that adequately addresses the risk from UXO.”


K Stone, K., Murray, A, Cooke, S. and Foran, J. (2008) ‘Unexploded Explosive Ordnance (UXO) – a construction industry guide’. Report RP732, CIRIA, London



Although every effort has been made to check the accuracy of the information and validity of the guidance given in this publication, neither the author nor the Federation of Piling Specialists accept any responsibility for mis-statements contained herein or misunderstanding arising herefrom.

All brand names, trademarks and registered trademarks are the property of their respective owners.

Hong Kong
Why should we feel obliged to conduct an unexploded ordnance (UXO) search of our work site?

Because health & safety legislation dictates that you are required to provide a safe & secure working environment for your employees, subcontractors and any visitors to your site. To quote the HK Labour Department’s FACTORIES AND INDUSTRIAL UNDERTAKINGS ORDINANCE, CHAPTER 59:“The Factories and Industrial Undertakings Ordinance provides for the safety and health protection to workers in the industrial sector…” and…“Every proprietor should take care of the safety and health at work of all persons employed by him at an industrial undertaking by:

  • providing and maintaining plant and work systems that do not endanger safety or health;
  • making arrangement for ensuring safety and health in connection with the use, handling, storage or transport of plant or substances;
  • providing all necessary information, instruction, training, and supervision for ensuring safety and health;
  • providing and maintaining safe access to and egress from the workplaces; and
  • providing and maintaining a safe and healthy work environment.

If there is known to be a potential risk from UXO and you fail to take appropriate risk management measures, then you are not providing and maintaining a safe and healthy work environment!

But surely any explosive remnants of war (ERW) item fired, thrown, dropped or propelled during WW2 will be harmless by now?

Regrettably not and sometimes they become more sensitive with the passage of time.

But in Hong Kong the war ended many decades ago. Surely all the UXO has been cleared up since then?

No, because not all ERW were in view during and after the war:

  • Some items might have been buried by soldiers to get rid of them or to hide them from the enemy.
  • Others may have failed to explode on impact and are now buried beneath the ground in the form of a UXO.
So why doesn’t the Hong Kong Government recognize the problem and insist on UXO clearance works as a standard procedure for all potentially affected projects?

Most likely because government officials are as unaware of the risks and legal consequences as everyone else.

The Hong Kong Police has a Bomb Disposal unit; why can’t they deal with the problem?

The HK Police Bomb Disposal unit reacts to the discovery of explosive items; they do not have the capacity to conduct UXO search & clearance works for Hong Kong’s entire civil engineering industry.

But come on, is there really that much of a risk from UXO in Hong Kong?

Hong Kong was a war zone during the Japanese invasion of 1941 and thereafter, until the Japanese surrender in 1945, Japanese shipping and air assets were targeted by USAAF and Navy bombers based in mainland China and on aircraft carriers in the South China Sea.

Yes, but all those artillery shells and bombs blew up didn’t they? Surely they no longer exist!

Most if not all munition types experience some failures when fired, thrown, dropped or propelled It averages between 8 and 14% depending on type. The reasons why they do not detonate as designed are many and varied but mostly unknown. So, it can be assumed that large numbers of ERW remain hidden from view and now present a risk to workers in the civil engineering industry.

But why bother to conduct UXO clearance if nobody has been killed or injured by such items recently?

Because there is a chance that ERW could detonate if they come into contact with personnel and/or machinery. If this happens, the outcome could be catastrophic. In a subsequent legal inquiry, the failure to have conducted UXO search could leave a company criminally liable under the HK Labour Department’s FACTORIES AND INDUSTRIAL UNDERTAKINGS ORDINANCE, CHAPTER 59.
Whilst nobody appears to have been killed or injured by UXO in Hong Kong, people are killed and injured by UXO elsewhere in the world every day.

But if the government doesn’t take it seriously and insist on UXO clearance as standard procedure, then surely we will not be liable if casualties are sustained as a result of UXO?

That may be the case if you can prove it in court but everyone in the contractual chain will be trying to shirk liability and shift blame to someone else. Are you willing to risk this?

Besides, UXO clearance is the professionally and morally correct thing to do where such risks exists.

What if we do nothing?

Well, the above Q & A answers part of this question (legal liabilities) but another consequence is expensive downtime caused by the discovery of UXO. If allowances for downtime, due to a UXO find are not covered in your contract, you may have to soak up the costs. You may even have to pay for the cost of a subsequent UXO clearance requirement.

So, what does all this mean?

Well, it means that if you are working in a former war zone, you should always ask yourself if you are likely to encounter a UXO problem. This question should be a standard part of any HSSE Risk Assessment process. If a UXO risk exists, ask your client if they have addressed it and, if so, how? You should also discuss the matter with your insurance company.

But isn’t the likelihood of encountering UXO low?

It depends where you are and what wartime activities took place there. But consider the well-known risk analysis: Likelihood X Consequences. The likelihood of encountering UXO may be considered low, but if you don’t know for sure, you are at risk. And the consequences of encountering UXO are almost certainly unacceptable.

OK, so if we have to conduct a UXO clearance, how long does it take and how much does it cost?

How long does it take?

This depends on a number of different factors, for example:

  • How big is the area that needs to be searched/cleared?
  • Does the area’s size allow for the deployment of more than one search team (for safety reasons, search teams cannot operate in close proximity to one another in small areas)?
  • To what depth must it be cleared (this will be dictated by how the area is to be used in future – foundations, pipeline etc.)?
  • What is the terrain (flat, undulating, hilly etc.)?
  • What are the ground conditions like (swamp, sand, mud, clay, rock etc.)?
  • Is the area likely to be contaminated by scrap metal (a UXO search must assume each metal item could be part of a UXO and must therefore be investigated)?
  • How close is the search area to:
    • other structures
    • areas of habitation (this may require the construction of protective works)?
    • overhead services such as power cables
    • underground services such as pipelines
    • highly magnetic geology


How much does it cost?

The sample factors listed above demonstrate that a UXO search can be quite complicated. However, any professional commercial UXO clearance contractor MUST recognize and understand the commercial constraints faced by clients.

As such, the clearance contractor must provide a proposal based on common sense and best estimates with some contingencies built in. This will be arrived at through the conduct of a thorough reconnaissance and needs assessment combined with the experience and expertise of qualified personnel.