Night Delivery, a Wet Coupling, and a Clerk With a Clipboard
It is 23:20. You are delivering 8,200 gallons of gasoline (UN1203, Class 3, PG II) to a 24-hour station. The tanker is an MC-306 with a single compartment dropping into the station's regular-grade fill. You set the parking brake, chock the wheels, shut down the engine, and connect the 4-inch hose to the tank's API adaptor. The station's fill pipe is on the far side of the lot, roughly 60 feet from the truck. You start the pump, take your position at the manifold with your hand on the deadman control, and begin the drop. Two minutes later the clerk walks out, asks you to come inside to sign the delivery ticket, and asks you to move the truck because a customer's car is blocked. At the same moment you notice a wet streak running down the hose coupling and a dark patch spreading underneath it.
1. Give your immediate actions in order. Why does sequence matter here?
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Release the deadman first. That stops the pump and lets the internal valve close, and it is the only action that stops the release from growing. Everything else can wait two seconds. Then keep the clerk and any customers back, enforce no smoking and no running engines within 25 feet, and do not restart the pump.
Sequence matters because every other action either adds product to the puddle or puts a person into it. Walking to the cab to shut down from a switch, going inside to sign, or moving the truck would all extend the release or drag a charged hose across a fuel spill. Once flow has stopped, assess from upwind: how much product, whether it is reaching a drain, whether the coupling or the adaptor gasket is the source. Contain what you can reach safely with the spill kit and absorbent, and do not crawl under the trailer in the dark in a vapor cloud. Call 911 if the release is significant or reaching a drain, notify your company's 24-hour line, and notify the station manager. Do not restart the delivery. Tag the hose and coupling out of service, because a coupling that wept gasoline under pressure will weep again.
2. Address the clerk's two requests under the attendance and unloading rules.
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Both requests are declined, and the reasons are different. Attendance during unloading means staying close enough to the vehicle and the transfer point to have an unobstructed view and to be able to shut the operation down at any moment. Most state and federal framing puts that at within about 25 feet. Walking 60 feet across the lot and through a door to sign a ticket puts you out of position and out of sight, so the operation would be running unattended. Also, you do not sign a delivery ticket while product is flowing; it is the last step, after the drop is complete and the hose is disconnected.
Moving the truck is worse. With the hose connected to the station's fill pipe, moving the truck pulls the adaptor, tears the hose, or drags a live hose across the lot. Never move with a hose connected. The customer in the blocked car waits, or is asked to back out, and if that is not possible the clerk handles it.
Note that the engine stays off during the drop unless it is required to drive the pump, the brakes stay set, and the wheels stay chocked. Those are all set before product moves, not adjusted afterward.
3. The coupling leak turns out to be small - a few ounces on the pavement. What has to happen before you leave, and how do you decide whether this becomes a reportable incident?
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Before you leave: flow stopped, spill absorbed and the absorbent containerized and removed from the lot rather than left in a puddle, the source identified (adaptor gasket, coupling, or hose), the hose and coupling tagged out of service, the discrepancy documented on the delivery paperwork so the station's inventory is not short, and the station manager told what happened and what was cleaned. Your company's dispatch and maintenance get a call the same night. Photograph the coupling and the stain before cleanup.
Reportability: the question is not whether the driver thinks it was small. It is whether the release meets a reporting criterion. A few ounces of gasoline absorbed on pavement with no fire, no injury, no evacuation, no closure of a road, and no reach to a drain or waterway generally does not meet the criteria and does not require a National Response Center call. What changes the answer is any of the following: product reaching a storm drain, soil, or water; a fire or the threat of one; anyone injured or taken to a hospital; the public evacuated or traffic stopped for an hour or more; or a continuing danger at the scene. Gasoline is also a hazardous substance with a reportable quantity, so if the volume is meaningful or the release is to the environment, call the National Response Center at 1-800-424-8802 and follow with the written report. When the facts are ambiguous, call; the call is free and the missed call is not.