The Charity
Aviation
Maritime
CHIRP continues to receive many reports relating to MARPOL. One report below details concerns with grey water, with the other highlighting a potential pollution scenario.
Our vessel transferred a quantity of bilge water from the engine room bottom plates to the grey water tank using an air pump. The bilge water was not treated, nor was the event recorded in the oil record book. The grey water tank was subsequently discharged to sea as normal grey water, which of course by-passed the oily water separator.
With the consent of the reporter CHIRP wrote to the DPA of the company and received the following detailed response:
We are aware of the case you refer to, and we have recently completed an extensive investigation into the matter. Our investigation has concluded that in the case witnessed by your reporter, an amount of fresh water from a leaking laundry pipe was indeed pumped from the tank top into a greywater tank. However, as soon as the Chief Engineer became aware, the greywater tank was immediately isolated.
The grey water tank in question had not been emptied since well before the incident date, hence nothing was pumped overboard. The tank content was later delivered to a shore facility as oily bilge water. Our investigation pointed out several corrective actions, one of them being a Safety Bulletin for discussion and circulation to all fleet vessels. This stated inter alia;
During maintenance on a diesel generator, the low temperature cooler was removed for cleaning, but the SW supply isolation valve failed to hold. With the cooler already removed, sea water was able to flood into the engine room. The bilge level reached 0.3m before a decision was made to operate a pump to reduce the flood level and prevent damage to other machinery. Additional isolations were made to stop the water entering the space. Bilge water mixed with floodwater was pumped directly to sea. On reflection, it was realised that the threat posed to the ship from the flood was less than the potential impact of releasing contaminated water to the sea and the floodwater should have been held onboard in the bilge holding tank before being discharged through the separator.
Notwithstanding the differences in opinion between reporter and company in the first report, the message as stated in the company bullet points is clear. MARPOL must be complied with, and all water from E/R bottom plates or tank tops must be considered as bilge water and treated accordingly through the oily water separator.
The second report highlights a concern for protection of the environment – albeit in hindsight. It also highlights the subtle difference between an emergency and a situation where saving the vessel overrides MARPOL (which was not the case in this instance).
CHIRP is becoming increasingly aware that regulations prohibiting discharge (such as within special areas) is having a knock-on effect so that a vessel’s capacity to hold all of its bilge, waste oil or grey water is becoming increasingly strained. Designers take note! We would like to hear more about these issues for further debate.
Report Ends