Guidelines for Demolition Works

Clearance must be sought from the Regional Environmental Manager prior to any demolition activities being commenced using the Environmental Clearance Policy Guidance and Environmental Clearance Certificate Templates.

 The following must be adhered to and provided as part of the original works.

• No demolition works are to be carried out until all necessary survey and investigations are performed.
• All redundant above ground structures including footpaths, etc are to be removed.
• All redundant in-ground footings are to be removed.
• All underground services are to be isolated, capped and terminated and reflected on the “As Constructed” drawings or documented in he region’s spatial information.
• The site is to be cleaned, levelled and rejuvenated to match the surrounding area.
• An environmental audit of the cleared site is to be carried out.
• All demolition works are to comply with relevant Codes and Standards.
• All materials from demolition are to be removed from Site.

Recycling

 Where demolition is identified as the most appropriate means of disposal, the Project Manager should be mindful that while the structure may have no further value to Defence, the materials that made up the structure may still have a residual value as reclaimed or recycled construction materials. An assessment of the residual value of such materials may be undertaken at the discretion of the Disposing Approval Authority.

 In such cases the Request for Tender should identify approximate quantities of materials suitable for salvage or have a statement that the contractor may take into their calculations the sale of any recyclable products from the demolition works.

Common demolition hazards

Following is a list of common hazards associated with demolition works.

Asbestos
Many Defence Facilities constructed prior to 1991 have asbestos in them. Asbestos is a human carcinogen, which can cause serious health problems when disturbed and inhaled. Project officers should check the asbestos register on DEMS prior to commencing any demolition works.  Further information on how to manage asbestos in the Defence Estate can be found at Defence Occupational Health and Safety.

Asbestos may be found in many forms throughout a building. Including:

• Heating, Ventilation and Air Conditioning Systems normally found in the form of gaskets and cladding.
• Floors may have asbestos in the form of vinyl asbestos floor tiles
• Exterior walls may have asbestos in transit sidings, asbestos cement sheeting, stucco.
• Fire doors are often lined with asbestos.
• Roofs may be made of asbestos roofing. Asbestos was often used around chimneys and vents. Flashings may also contain asbestos.
• Electrical switchboards may contain asbestos, Insulators, spark arresters and some light fixtures.
• Ceiling tiles, and jointing compound.
• Insulation in ceilings and walls (sprayed in)
• Fire curtains and blankets. Laboratory tabletops, Fume cupboards, blackboards.

CFCs, Halons and other refrigerants.
Hydrochloroflurocarbons (HCFCa) and halons are manmade substances that damage the earth’s protective ozone layer high in the atmosphere allowing greater exposure to the sun’s dangerous ultraviolet rays. They are known as ozone-depleting refrigerants.

CFC etc may be found in older air conditioning systems, fridges freezers and in some fire control systems. Water Fountains/Coolers, heat pumps, dehumidifiers and vending machines may also contain CFCs.

The release of CFCs into the atmosphere is prohibited under Federal Law. When identified within a structure the most appropriate method of disposal is to have them removed by a professional with a gas scavenging pump. They are then taken to a place of disposal where they are destroyed in a high temperature furnace.

BCF Fire extinguishers use Halon. Their use was banned in 1993. BCF Fire Extinguishers are easily recognised as they are painted yellow in colour. If found within a Defence Structure they are to be removed and handed to the Environmental Section for disposal.

Lead
Inhaling or swallowing lead can cause serious acute or chronic heath affects to the brain, endocrine, reproductive and immune systems.

Lead was commonly used in buildings up to the mid 1970s. Normally found in plumbing and flashings lead can be easily scavenged and may have a residual value. Lead should not be sent to land-fill.

Lead acid batteries may be found in exit lights. These batteries should be disposed of utilising the procedures listed on the Army Battery Safety Site.

Lead Paint
Prior to 1978, lead based paint was commonly available. Normally used on the exterior of buildings, lead paint poses a serious risk to if it is removed using scouring tools such as sanding disks, scrapers or dry blasting. Wet blasting is not recommended, as the residual grit will be contaminated with small particles of lead, which may be inhaled. Preferred method is the use of a wet-gel paint stripper and encapsulation of the scrapings.

Mercury
Mercury is a heavy, shiny silvery-white poisonous metal that is a liquid at room temperature. Mercury is commonly found in older style thermometers, barometers, thermostats, dental offices (used in amalgam fillings) blood pressure devices, older fluorescent and other light bulbs. Mercury evaporates at room temperature and gives off a harmful odourless vapour. Ingestion of mercury especially breathing its vapour is harmful to humans. Do not remove mercury from the device in which it is encapsulated. When found it should be stored in a covered container to prevent damage. Most mercury devices can be recycled.

Mercury may be found in High Intensity Discharge lighting systems including metal halide, high pressure sodium, mercury vapour and Neon.

Polychlorinated biphenyls (PCBs) 
Polychlorinate biphenyls are uncommon but they may still be found in older building that have been used for long term storage or low use areas.  PCBs were used in many electrical devices such as capacitors, transformers and most commonly in lighting ballasts. PCBs were incorporated into oils to prevent their breakdown at high temperatures. PCBs continue to be a major source of fish contamination.

PCBs all but ceased to be produced after 1978 however if the electrical system of a structure is likely to be older than this date then their presence should be assessed as likely.

Other Environmental Issues

Emergency Exit Signs. Many self luminous exit signs contain significant amounts of radioactive tritium. Such devices need to be disposed in accordance with environmental regulations burial in an appropriate land fill being the preferred method.

Smoke Detectors. Smoke Detectors are likely to contain radioactive americium 241 however the amount is so small approximately 0.0002 grams per detector they are not considered dangerous to the environment and can be disposed of as normal household waste.

Solid Waste. Recycle where possible. Under no circumstances is solid waste to be burnt.

Wood Waste. Wood may be recycled and may have a residual commercial value.

Metal Waste. Consideration should be given to sending metal waste for recycling.

Liquid Waste. Liquid wastes in particular petrol’s, oils and lubricants should, where possible, be reclaimed through the use of a reputable chemical recovery company. Liquid wastes are not to be dumped at land-fill nor should they be incinerated.  

Soil Contamination. Soils may be contaminated either through the long term exposure to by-products of the sites use or from termite or other pest control measures. Products such as Dioxin were commonly used as a termite treatment prior to 1975. Testing of soils prior to commencement of works should be undertaken as a precautionary measure. Testing may be arranged through the Environment Management Section.