Guy Lucas puts the case for tighter laws to govern the identification and removal of unexploded ordnance.
Unexploded ordnance is probably the riskiest form of land contamination for developers - and site workers - but one that is often overlooked.
Areas such as historic dockland areas, old commercial ports, former airfield sites, former munitions manufacturing sites, railways and oil and gas installations are prime targets for redevelopment.What is not always obvious, however, is that each site could be a time bomb just waiting to explode-metaphorically and literally.
During the Second World War, about 10% of British and German ordnance failed to function as designed, leaving a legacy of unexploded material.Many businesses also manufactured, fitted or procured explosive ordnance, not always under ideal conditions, and sometimes items were disposed of on site.
As a result, both brownfield and greenfield development can potentially bring construction workers into direct contact with unexploded ordnance and contamination from its manufacture.
What is particularly shocking is that some form of ordnance is encountered almost every day in the UK, but most of it remains on site.
Despite having lain dormant for many years, these items may still detonate and cause serious injury or loss of life.Unexploded ordnance poses not only an immediate operational and health and safety risk but could also cause a legal and financial catastrophe for developers.
Demand for the effective clearance of unexploded ordnance has risen dramatically as legislation addresses health and safety on construction sites and identifies the responsibilities of various parties in respect of contaminated land.
While the Construction (Design and Management) regulations (CDM) introduced in 1994 aim to reduce all risks on construction sites, there is no law specifically obliging developers and construction firms to have land certified free from unexploded ordnance before development.
The UK is lagging behind some of its European partners in this respect.
The Netherlands'planning process has a statutory requirement for unexploded ordnance risk mitigation to be carried out and certified before development can proceed.
What is needed in the UK is a tightening of the law to force landowners and contractors to consider this particular threat before work begins on site.Of course an emergency response plan can be implemented as and when ordnance is discovered.However, this may significantly disrupt the project and in no way safeguards the construction team or the surrounding population.
Bomb disposal, or explosive ordnance disposal (EOD), as it is more formally known, is a very specialised industry which requires knowledge of the characteristics of weapons past and present, their detection, access, identification and disposal.
A variety of intrusive and non-intrusive survey technologies are available that can identify and locate possible items of explosive ordnance.The technology is constantly being developed to improve capabilities and efficiency.
Having worked in the EOD and landmine clearance arena for more than 33 years, I am all too aware of the need for the effective detection, identification and disposal of unexploded ordnance.
However, not all landowners and developers are.
The developer should put the safety of workers and end users first, no matter how small the risk may be.It should not take a tragic event to make the government and industry take serious action on this issue.
Substances like asbestos and heavy metal contamination are often seen as the most dangerous contaminants to be unexpectedly found on a development site.Given the legal, financial and human risks posed by a potential detonation on site, it seems ironic that explosive ordnance remains the often forgotten contaminant.
Guy Lucas is managing director of explosive ordnance disposal and landmine clearance firm Bactec International.