UXO in Canada
Unexploded Explosive Ordnance (UXO) are military explosives that did not explode or function as intended. Some examples of UXO are bombs, rockets, grenades, artillery shells, flares, mortars, and hazardous residues that may remain after a partial or failed detonation. If touched or disturbed, UXO can cause injury or death.
UXO Legacy Sites are former military sites some of which were used by Canadian and Allied troops for live fire training during conflicts such as World War I, World War II, and the Korean War. Some of these sites may still pose an explosive risk to the public. There have been UXO incidents in Canada which have resulted in both the injury and death of Canadian Civilians.
The Government of Canada retains responsibility for UXO on Canadian Land and within its territorial waters. The Unexploded Explosive Ordnance (UXO) Legacy Sites Program manages UXO risks on UXO Legacy Sites across the country contributing to the health and safety of Canadians.
DND's Assessment and Prioritization Process for UXO Legacy Sites
In 2006, the Department of National Defence (DND) began a comprehensive review of historical records to identify sites across Canada where past military activities may have left behind unexploded explosive ordnance (UXO). These sites, known as UXO Legacy Sites, are no longer owned by DND, but they may still contain potentially dangerous UXO. UXO Legacy Sites are not new, but they are coming into the public eye more and more because of changing land use in support of our growing population.
As land use across Canada changes, areas that once served military purposes are now being used for other activities, from housing to recreation. Understanding the risks posed by UXO is essential to keeping people safe. UXO Legacy Sites are prioritized and investigated by DND to determine which sites may require work aimed at assessing and mitigating UXO Risk.
The Process: How DND Assesses and Manages UXO Risks
1. Gathering Historical Data
- DND's researchers reviewed a wide range of sources, including national archives, military records, and local newspapers, to form a picture of where Canadian Military and Allied Forces trained in Canada and understand what types of munitions were used at these sites. This process was used identify and prioritize sites that might still have UXO.
2. Site Prioritization
- Historical Records were also used to compile a list of Priority Sites where UXO issues may remain to this day. Prioritized UXO Legacy Sites were scheduled for site visits to confirm site conditions and fill any information gaps.
3. UXO Risk Assessment
- UXO Risk Assessments are prepared by DND experts who use established procedures and site-specific information to determine UXO risk based the type of munitions which may be present.
- There are four potential UXO risk scenarios which result from a UXO Risk Assessment: No UXO Risk; Low UXO Risk; Medium UXO Risk; or High UXO Risk.
- Canada's portfolio of UXO Legacy Sites is comprised of sites which are classified as "in Assessment", "Assessment Complete", "Risk Mitigation On-Going, or 'Closed".
- A UXO Risk Assessment marks the final stage of a sites Assessment.
- A sites UXO Risk is used to determine future Risk Mitigation requirements or the potential for site closure.
4. Understanding UXO Risk
- Risk levels are based on the type of UXO and the intended land use. The UXO Risk is a function of both the potential presence of a UXO and a specific activity which may cause someone to both come into contact with a UXO and do something to cause it to function (i.e. explode, burn, or release its payload). For example, non-intrusive land used (i.e. no on-site excavation) could pose a low UXO risk on a particular UXO Legacy Site, while construction of a swimming pool on the same site could pose a high UXO risk.
- There are four UXO Risk levels:
- No UXO Risk
- Low UXO Risk
- Medium UXO Risk
- High UXO Risk
- Sites with No UXO Risk and Low UXO Risk are generally considered safe and do not require any specific UXO Risk Mitigation in advance of any on site physical works. Although as with any excavation work there is always the potential for unknown subsurface hazards, so on-site workers should always have an understanding of basic health and safety protocols.
- Sites with Medium or High UXO Risks generally require additional safety measures aimed at mitigating any potential UXO Risk and thereby maintain the health and safety of site workers and the public.
5. Managing UXO Risks and Closing Sites
- UXO Risk is used by DND to inform decisions regarding UXO Risk Mitigation or site closure. Sites with no or low UXO risk may be administratively closed, while Medium or High Risk UXO sites often require some form of UXO Risk Mitigation to be protective of human health and safety.
- Administratively Closed Sites can be re-opened at any time should new information come to light which suggests an unacceptable UXO Risk
Examples of Risk Mitigation Measures
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Communication
Communication is one of the department's most efficient ways of ensuring public safety and reducing the risk of injury or death associated with UXO. The program communicates with stakeholders within a given community about the potential UXO risks, as well as the risk management and mitigation actions being taken to ensure public safety. Safety messages are communicated through the program's website. The program also delivers presentations to elementary and high school students and conducts public information sessions in specific communities where there is an elevated chance that people could encounter UXO.
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UXO Signage
UXO warning signs are strategically placed at sites where UXO may be encountered to alert the public to the potential dangers of UXO and to provide information about what to do if a UXO item is found.
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Survey
A survey is used to locate the potential presence of UXO at a site. The survey provides a geospatial reference point where the UXO may be located. There are a variety of technologies that can be used to conduct surveys both on land and underwater. Following careful analysis, the experts safely uncover the selected objects to determine whether they are UXO.
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UXO Clearance
During a clearance operation, UXO are unearthed and identified by a team of trained Explosive Ordnance Disposal (EOD) professionals. When UXOs are found they are either removed for destruction elsewhere (if safe to do so) or detonated in a controlled manner and the remaining scrap metal is then gathered-up and shipped off site for disposal at DND facilities. Clearance operations are resource and time consuming. Unfortunately, there is no technology available today that guarantee all UXO on a site have been located and removed.
What should you do?
Where UXO warning signs have been posted, obey the instructions and stay safe!
If you find something that could be UXO...
- Don't touch it! If disturbed, UXO can explode, causing death or injury.
- Remember the location and leave the area Remember where you saw the object. Go back the same way you came.
- Call 911 or local police As soon as possible, report what you found by calling 911 or contacting local police.
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