After crew change the other day, I spent some time telling the relieving tankerman about the ins n' outs of our new crude oil run. We discussed procedures, plans, contingencies... all the good stuff, as well as the practical things. This was followed up with a relatively small cargo parcel to be loaded, and discharged at a terminal we normally wouldn't visit on this contract.
When it was time for me to sleep, my tankerman had things well in hand. We were discharging to the terminal, and I went to bed. He would finish the discharge, walk the cargo surveyor through the paperwork, and get us ready for a draft load of crude oil the next day.
I woke up to find us at the load terminal, a few hours from where we were when I went to bed. As is my way, I felt the normal bumps and vibrations when we sailed and arrived at the next dock, and they, being normal, were enough to register, but not enough to fully wake me up. When I arose my tankerman asked me if we were letting the terminal blow their lines into our tanks.
At the end of a cargo evolution, there is going to be oil in the pipelines, hoses and connections between ship and shore. Depending on the cargo, this can be dumped, drained or pushed elsewhere using air or nitrogen (depending on the cargo).
Crude oil contains a little bit of everything, including a shit load of things that are very volatile. On top of that, it's a strong static accumulator- that is, it collects electrical current generated by the friction of the oil passing through pipelines. There are smart ways to handle it, and not so smart ways.
We're pretty careful folks here at HAWSEPIPER's afloat global HQ/fertility clinic. Little things like letting the cargo sit undisturbed for 30 minutes before gauging volumes do wonders for letting static dissipate. We DON'T have an inert gas system like a ship would. Ships pump inert (non explosive) gases into their tanks to make ignition improbable. We don't have that luxury, so we have to be smart.
The dockman at this dock (who doesn't deal in crude, but does have a connection to an interstate crude pipeline that they never really use), at the completion of the discharge, set up to blow compressed air into his pipe manifold, to drive the residual oil back into our tanks. My tankerman wisely declined, as we don't want air and oil to be compressed in our underdeck pipelines where there's a possibility of ignition (plus, any air trapped will skew our volume measurements- the couple of tons of oil left in our pipelines belongs to the customer, and they don't like paying for air bubbles). SOP for us is to drain the lines using only gentle gravity if the shoreside folks don't want a shot of air.
The dockman proceeds to browbeat my tankerman, saying that 'we always blow back to you guys' (bear in mind that we've never been to this dock and my employers haven't ever carried crude oil in the class of barge I run) and threatens to dime him out to Corporate for being uncooperative and ignorant of normal procedures.
Thankfully, my tankerman, for some uncharacteristic reason, gives the dockman my company's 800 number and offers to let the man use our phone. I had no idea the man had it in him.
At any rate, I was fairly bent out of shape by this- I'm highly satisfied by what my 2nd man did, but pissed about what the dockman wanted to do, all in the name of avoiding having to turn one little valve and put a couple of barrels of stinky crude oil in his containment area. 3 minutes delay isn't worth the trouble of blowing us the fuck up.
And if you want to see what stupid shortcuts can do to folks in my position, look at this: