Leaking drum found at a lay-by during a parking stop
A driver parks a vehicle carrying UN 1830 sulphuric acid (class 8, PG II, 20 × 200-litre polyethylene drums in a curtain-sided body) at an unsupervised lay-by at 23:40 because the permitted parking place is full. At 06:00 the driver finds a pool of liquid under the rear of the body, a sharp acidic smell, and one drum visibly deformed with its bung seeping. The body floor has a wooden deck; the spill has soaked into it and is creeping towards a drain grate 4 metres away. The driver has one 5 kg ABC extinguisher, a 2 kg CO2 extinguisher, goggles, gloves and a small spill kit with 10 kg of absorbent. It is raining lightly.
1. What are the immediate priorities in the first minutes?
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First, protect people and the environment: keep bystanders upwind, put on goggles and acid-resistant gloves, and do not kneel in the pool. Second, stop the source: the leaking drum should be uprighted if it has rolled, and the bung tightened or the drum transferred into an overpack or salvage drum if one is available; if not, the drum should be laid with the leak uppermost so liquid, not vapour, escapes. Third, stop the spill reaching the drain: the absorbent should be used as a dam or sock across the floor and at the drain grate before mopping, because once acid enters the drain the environmental harm and the reporting obligations escalate sharply. The driver should call the emergency services and the consignor's emergency number immediately - a class 8 spill of this size is not a 'clean it up quietly' event. The extinguishers are irrelevant to an acid spill unless there is fire; they must not be used to 'wash' the spill.
2. What are the driver's reporting and documentation duties, and what should not be done?
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The driver must inform the emergency services, the employer and the consignor, and give the UN number, proper shipping name, class, quantity involved and location. The transport document and the instructions in writing must be available to the responders; the driver should hand over the written instructions rather than improvise. The incident should be recorded: time, place, what leaked, quantity, actions taken, absorbent used, and disposal route for the contaminated absorbent and the damaged drum. The driver must not hose the spill into the drain, must not neutralise with an unknown substance, and must not load the leaking drum back among sound drums. Contaminated absorbent and the damaged drum are themselves dangerous waste and must be consigned for disposal, not left at the lay-by. Parking at an unsupervised lay-by was itself a supervision failure that must be reported honestly.
3. What does this incident reveal about the parking decision and the vehicle equipment?
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ADR supervision rules require a vehicle carrying significant quantities of dangerous goods to be parked under supervision or in a secure place, and a lay-by chosen only because the proper place was full does not meet that standard. The driver should have contacted the employer for an alternative secure site rather than parking unsupervised. The equipment is also inadequate for this load: a small general-purpose spill kit of 10 kg cannot absorb 200 litres of acid, and there is no acid-resistant overpack or salvage drum. The vehicle should carry spill equipment appropriate to the class and quantity, and the driver should have checked the drums' closures before departure. The wooden deck means the acid cannot simply be washed off; the contaminated decking must be dealt with as hazardous waste. All of this belongs in the post-incident report.