Sheen at the Manifold During a Night Transfer
At 0200, during a night transfer of diesel from a barge to a shore tank, a deckhand reports a light sheen on the water at the barge's manifold. The transfer is running at about 800 gpm. The manifold area is dimly lit, the deckhand is not sure whether the sheen is new or from an earlier operation, and the terminal's night crew is minimal. The barge has absorbent boom and pads aboard, and the terminal has a spill kit at the rack. The tide is ebbing toward a nearby marsh.
1. What is your first action sequence, and why does order matter?
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Order matters because every minute of continued transfer adds product to the water and the ebbing tide carries it toward the marsh.
- Stop the transfer (or reduce to zero) first - do not investigate while product continues to flow. A suspected leak at the manifold means the source may be the transfer itself.
- Notify the terminal and the PIC immediately, and make the required notifications (company, and the National Response Center if the discharge meets reportable quantity - a sheen on navigable water is generally reportable).
- Identify and isolate the source: check the manifold, hose, and connections; close valves to stop the release.
- Deploy boom and absorbents to contain the sheen on the water and protect the marsh side, using the ebbing tide to your advantage by setting boom to deflect rather than chase.
- Document: time, location, estimated volume, actions, and notifications.
Investigating before stopping the transfer is the classic error - it guarantees a larger release.
2. How do you use the tide and the available boom to protect the marsh?
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The ebbing tide is carrying the sheen toward the marsh, so you set containment between the source and the marsh, not at the source. Practical approach:
- Deploy boom in a deflection configuration angled to the current so the sheen is guided to a collection point on the open-water side rather than into the marsh channels.
- Prioritize the marsh-side approach: the marsh is the sensitive receptor, and once oil enters the channels it is very hard to recover.
- Use absorbent pads/boom at the manifold and along the deflection line to pick up the light sheen.
- If boom is limited, protect the marsh first and the open water second.
- Coordinate with the terminal's spill kit and any response contractor; do not attempt a large recovery with only barge gear.
The judgment point: containment is placed by where the product is going, not where it came from.
3. What records and notifications are required, and what would you tell the night terminal crew?
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Records and notifications:
- Notify the PIC/company and the terminal; make the required federal/state notifications (National Response Center for a reportable discharge; a sheen on navigable water is generally reportable).
- Record in the deck log and oil record book as applicable: time observed, time transfer stopped, estimated volume, source, containment actions, boom deployed, notifications made, and names of persons notified.
- Preserve evidence: photos, the manifold condition, hose condition, and gauge/transfer records.
To the night terminal crew, be direct and specific: transfer is stopped, there is a sheen at the barge manifold, do not restart until the source is found and contained, deploy the rack spill kit to the marsh side, and here is who is calling whom. Assign one person to notifications and one to containment so neither is dropped. Keep it factual - no speculation about volume until you have an estimate.