APPARATUS FOR REMOVAL OF HAZARDOUS OR TOXIC WASTE This invention relates to the removal of hazardous and/or toxic waste, and in particular relates to the safe removal of such waste from locations such as buildings. One wel l-known hazardous material is asbestos. Asbestos is now recognised as a very dangerous substance, the cause of serious - almost fatal - diseases such as asbestosis and mesothe 1 ioma . Mesothelioma is a cancer caused by as asbestos fibres- it is believed that the condition may be brought on by a single fibre. Asbestos is no longer being used as a building or insulation material, although it was being supplied to the market in Australia as late as 1986. However, buildings containing asbestos are a presen being demolished or renovated, and 95% of buildings in Australia contain some form of asbestos. orkers with asbestos are protected by regulations - see for example the 1978 Labour and Industry (Asbestos) Regulations of the State of Victoria, Australia - but there are types of asbestos removal , such as the removal of asbestos roof and wall sheeting, where neighbours of a dwelling being processed for asbestos may be exposed to asbestos fibres. In addition, current methods of removal are clumsy and leave a lot to be desires. Asbestos is being removed by hand, placed in plastic containers loaded into open trucks and dumped into predug holes at tips. Although breathing apparatus, suit and gloves are used in conjunction with plastic screens, there are still hazards. The main hazard seems to be that the plastic tears and the asbestos inside is still in a dangerous dusty mode. If the plastic tears, asbestos dust escapes on site, in transport, and when disposed of at the tip. Even if the plastic does not tear when unloaded at the tip, there are two problems. A large plastic bag in the ground when surrounded by water will f loat, and many have f loated to the ground surface. Further, when bulldozers working in the tip run over the plastic bags close to the surface the bags explode and vent

dangerous dust, Asbestos is of course not the only hazardous substance to be a cause for concern. As recently as December 1988 the Trades Hall Council in the State of Victoria, Australia passed a resolution calling upon the removal of fibreglass insulation to be regulated in the same way as asbestos removal, because of concerns about the health effects of glass fibres. It is an object of this invention to provide improved hazardous and/or toxic waste removal apparatus. The invention provides apparatus for removal of hazardous or toxic waste, including a compartment for receiving said waste, said compartment having an opening through which said waste passes when it is being placed in said compartment, and means adapted to provide a curtain of liquid spray across said opening, for wetting said waste and preventing egress from said compartment of waste particles. Embodiments of the invention will be described in detail hereinafter, with reference to the accompanying drawings, in which:- Fig. 1 is a perspective view of a waste removal container: Fig. 2 is a perspective view of another form of vacuum cleaner head for use with the container of Fig. 1: Fig. 3 is a perspective view of the container of Fig. 1, showing the lids closed: Fig. 4 is a perspective view of the container of Fig. 1 operating at ground level: Fig. 5 is a side elevation of the container of Fig. 1 being lifted off or picked up: Fig. 6 is a side elevation of the container of Fig. 1 being unloaded at a tip. Fig. 7 is a perspective view of a landfill operation: and Fig. 8 is a side elevation of another embodiment of waste removal container. Referring firstly to Figs. 1 to 4 inclusive, the waste removal container 10 is of generally cuboidal shape.

- 3 Preferably, the container is a roll-on roll-off bin havi dimensions approximately 6.7m x 2.4m x 1.9m with a weight just under 4t. The bin is preferably formed from meta for example steel. The interior of container 10 has three-sections; a ma waste storage compartment 12, a vacuum compartment 14 and machinery compartment 16. The container 10 has two longi udinally hinged l members 18,20, which are able to move from a closed positi (Fig. 3) to a fully opened or platform position (Fig. 1). The container 10 has three hydrau 1 ica11 y operat telescopic legs 22,24,26 and two 'lazy' telescopic le 28,30 which may be pinned at a desirable telescop position. There is a safety lock built into the system that the container 10 cannot collapse in the Fig. 1 rais position . Lids 18,20 are as we have stated hinged along the upp longitudinal edges of container 10. They are each provid with a rubber sealing flap 46 to prevent dust or wat escaping between the lids and/or between the lids and t container. They are counter sprung to ease opening. ensure that they can be closed, a line will be drawn on t container 10 providing a maximum capacity of waste. Each lid (lid 20 is illustrated in this position) m be used as a platform for workers 32,34. For this purpo the lids - each of which is preferably made from steel tre plate - has tread 38 located thereon. Railings 36 may inserted into apertures on the lid, for safety purpose The lids 18,20 have supports 44 (Fig. 3) on top to preven sagging. When being closed, when the rubber portions mee the lids tendency to sag ceases. Preferably, each support is formed from hollow tube. Support arms 43 fold from a first position parallel t the sides of container 10 to a position normal theret (inset, Fig. 1) to support platform 20 in the 'platfor position 40. The arms have spring-loaded catches to loc them in both positions. Lid arms 43 and supports 44 are staggered and slo

alongside each other when the lids are open. Lids are locked on to each other and on to each end by an hydraulic operated slide, locking down in five places (not shown). The container 10 has skids 42 located on the underside thereof, as well as four large rollers (not shown) to assist in moving the container 10. There is a tail gate 48 (Figs. 1 and 6) which is hinged at the top, and a chute 50 (Fig. 6) with tapering sides, which is hinged at the base of the end of the compartment 12. The chute 50 will preferably be hy dr au 1 i cal 1 y operated, or of the counter sprung or shock-absorber type lift assister type. Compartment 12 has openings 52,72 for the connection of vacuum hoses (54,70). When not being used, they are sealed with a cap. There is an aperture 56 between compartments 12,14. ater tanks 58,60 are located in or under compartments 14,12 respectively. Water conduits 90 (o l one of hich is shown) run the longitudinal sides of container 10 beneath the lid (18,20) hinge. Spray nozzles 62 provide a curtain of spray, as shown best in Fig. 1. A vacuum cleaner head 66 attached to hose 54 (Fig. 1) is adapted to pick up waste material. Alternative head 68 (Fig. 2) is useful in picking up loose asbestos dust. Motor 74 is located in compartment 16, and is preferably a double shafted internal combustion motor of 2900 r.p.m., coupled to a blower and an hydraulic pump. An oil bath 76 is provided in compartment 16 to clean vacuum air. A storage compartment 98 with a door 99 is provided beneath oil bath 76 to store safety equipment such as overalls, full face masks, gloves, mask filters and 'Compulsory Respiratory Area" signs. Adjacent in compartment 16 are fuel storage (78) oil storage (80) and water storage (82) tanks, above which is located a high pressure water pump 88 and a vacuum water pump, each of which is driven by the aforementioned hydraulic motor, which also supplies hydraulic power to valves 96. Also in compartment 16 are a tank 94 for sediment and

slush, and hydraulic valves 96 for supplying legs 22,24,26 through conduit 92. Operation of the container 10 will now be described, with further detail of components. In Fig. 1, the container 10 is shown at the 'first floor' position, in which legs 22,24,26 have raised container 10 to a level suitable for ork on remaining asbestos sheeting (for example) from the roof of a single- storied dwelling. Hence the use of platform 20. The floor of compartment 12 is a false floor, with apertures therein to allow passage of water to tanks below. Passage of only the smallest solid particles is allowed and these are subsequently filtered before waste water is drained or recycled. Waste water is collected into two troughs, with a false floor sloping towards them from the font to back, and back to front, and also each sloping from the centre to the outsides, giving four water outlet points. The tapering floor forms the top of three water storage tanks. The four water outlet points are linked to the sediment filtering system and then to the vacuum pump 86. A pressure ball float on the filter allows more water to enter from reserve tanks as required, and there is an overflow back to reserve tank 82, to allow the plastic bag on filter to be changed without water spillage. The bottom of the filter has a detachable bottom with a heavy plastic bag inside. This is held on by over-centre spring clips against a seal. The whole filtering system is see-through so that the amount of sediment can be seen. When full of sediment the plastic bags are removed, tied and placed in bin and another bag fitted. The pressure pump 88 draws from the reserve tank 82 and supplies water through conduit 90 to forty-eight water jets and ten mister jets (62) concealed under the angle iron edge of container, so potential damage is restricted to a minimum. The jets are quick release in case of blockage. The jets are placed so as to achieve total coverage of the entrance to compartment 12.

In the position of Fig. 1, container 10 may be used solely for larger pieces of material (sheets and part-sheets of asbestos roofing sheet) which may be thrown through the curtain of spray into compartment 12. The water jets 62 spray horizontally across the opening of compartment 12, and the spray/mist wets solids passing through it and traps rising dust, to render the material safe. This would have followed delivery of the container 10 to the site in the manner of a skip (but also see the subsequent description in relation to Figs. 5,6 and 8) and the operation of the hydraulic system to telephone legs 22,24,26 and to fix 'lazy' legs 28,30. Before the container 10 leaves the site at the end of the job, the lids 18,20 are closed against the rubber seals 46 and mechanically locked. All surplus water and sludge in the bin is pumped through the filters and stored in the storage tanks so that no water containing fibres can escape from the tail gate 48 should the truck carrying the container be on an incline whilst in transit if a seal becomes damaged. As far as the filtering system is concerned, prior to bin removal from the site:- a) The fluid and the sediment is placed in strong small plastic bags and placed inside the bin. b) The air to provide the vacuum is filtered approximately 98% by the self cleaning water jet screens then by the oil bath 76 then through the blower to an absolute filter 84 then through another absolute filter 84 for total safety. In the 'ground level' position of Fig. 3, the container 10 is more likely to be used with the vacuum apparatus. The blower in compartment 16 operates to create a partial vacuum in compartment 14 or (with shutter 56 open) in compartments 14 and 12. A single flexible hose 70 may reach up as far as ten storeys, to bring dust and other waste material into compartment 12, when hose 70 is coupled to aperture 72 (or one of apertures 52). The hose 70 can be used in two ways:

- 1 - a) either to such fluffy asbestos directly into the bin through an airtight flexible tube; b) to evacuate the air (in large volume) from around where men are working by hand preventing fibres from being flown or floating to sites where they can be dislodged later and become dangerous. Two absolute filters 84 filter outgoing air. On the vacuum side, suction goes to oil filter 76 then into compartment 12 through (water) self cleaning mesh filter. When using container 10 with lids shut the air also passes through another (water) self cleaning mesh filter between the two vacuum compartments 12,14 then to one of the three hose attachments (52,72) on bin, then to hose 70. The hoses 70,34 may have two attachments for safety dust collection: 1) a rigid vacuum head to lie beside sheet asbestos; or 2) a flexible head to adjust for other types of work. Thus, the container 10 of this embodiment may be used with its lids 18,20 open or closed, at ground floor or first floor level , and with or without the use of vacuum equipment. Turning now to Fig. 5, there is shown a truck 102, with a tipping portion 104, on which is located a winch 106 with a cable 108. Cable 108 is adapted to be removably secured to hook 110 or the like on container 10. Fig. 5 shows a container 10 being loaded or unloaded, in the manner of a skip, with the combination of hydraulic tipping and the use of winch 106 being used to lay the container 10 on the ground or pick it up therefrom. In Fig. 6, sludge and/or other material 114 is being dumped in a hole 112 at a tip. This is done via chute 50, with tail gate 48 firstly opened. The container is tipped, whilst being held by winch cable 108, and the contents fall under the influence of gravity. Hose 116 attached to tank 58 in compartment 14, is used to wash away (with high pressure water) material clinging to the outside of

container 10. In Fig. 7, a bulldozer 120 is shown burying the waste 114 at a desired depth of 2m. Preferably, such a hole 112 is lined. Fig- 8 shows a further embodiment, in which a liner 118, preferably of plastics material, is first placed in compartment 12. At the conclusion of a waste removal operation, the liner is closed - possibly by means of zips, heat welding or the like to provide a sealed bag for disposal. The bag may be provided with filtered apertures to drain water, but would otherwise be hermetically sealed, for more safe disposal, as shown in Fig. 7. Other forms of liners or bags may be used. It can be seen that the present invention provides an improved waste removal container, in which:- a) the design makes waste collection as safe as possible; b) the hazardous material is transformed into a safe form while in the truck, on site, and for transportation in a sealed unit. c) the safe material is tipped straight into a hole at a tip in a thoroughly safe dust-free form. The container 10, although specifically designed for asbestos, will handle many other hazardous dusts and some chemicals and vapours, as well as fibreglass material. The claims form part of the disclosure of this specification.