QUESTION 6.4.2

Disposal of contaminated water from internal spaces

Oil, Chemical, LPG, LNGPumproom, Forecastle, Steering Gear

What is being checked

The inspector is checking whether oily water or marine pollutants accumulating in forecastle, steering-gear and other internal-space bilges are identified, contained, monitored and disposed of through an authorised route.

Ready onboard

0/7 complete

SPACESThe procedure identifies every relevant internal space and bilge well outside the machinery-space system.PREVENTIONHydraulic and other pollution sources are maintained to minimise contaminated-water generation.MONITORINGBilge levels and contamination are checked by inspection or alarm at defined intervals.ISOLATIONArrangements prevent unauthorised or accidental overboard discharge.DISPOSAL ROUTEA practical transfer route to an approved holding, treatment or shore-disposal destination is defined.RECORDSEach disposal is traceable by source, quantity, destination, date and responsible person.CONDITIONBilges are reasonably clean and no unexplained oily accumulation is present.

Practice questions

Answer aloud, then open the preparation point.

1Which internal spaces can accumulate oil-contaminated water on this vessel?

Identify spaces from the ship-specific procedure, including forecastle, steering gear and hydraulic-equipment compartments as applicable.

2How is contaminated forecastle bilge water removed without discharging it overboard?

Use the approved portable or fixed transfer arrangement to an authorised holding or disposal route, with scuppers and overboard paths isolated.

3Show the record for the last hydraulic leak and resulting bilge-water disposal.

Link the defect, clean-up quantity, transfer or shore disposal and final bilge condition.

4How are unauthorised discharges prevented?

Show valve security, blanks, portable-pump control, hose management and access restrictions specified by the procedure.

5What action is required when a significant oily accumulation is found?

Stop the source, contain the liquid, notify the responsible officer, transfer it by the approved route and record both defect and disposal.

Where an observation may arise

PROCEDURE

Relevant spaces, monitoring and disposal routes are not defined.

ACCUMULATION

A bilge contains significant oily water or pollutant without action.

DISPOSAL

Evidence of a leak exists but there is no record of where the contaminated liquid went.

ISOLATION

An overboard path or portable arrangement permits unauthorised discharge.

EQUIPMENT

No adequate pump, hose, container or receiving capacity is available.

KNOWLEDGE

The responsible officer cannot explain the source-specific disposal route.

Master's practical note

Trace one hydraulic system in the forecastle to the bilge and then to the final authorised disposal point. The weak point is often the improvised transfer between the internal bilge and the ship's formal oily-water system.

Equipment boundary and references

Equipment boundary: Internal-space drainage arrangements differ widely. Confirm the approved route on drawings and in company procedures before transferring contaminated liquid.

References

OCIMF SIRE 2.0 Question Library Part 1, Version 1.0, Question 6.4.2
IMO MEPC.1/Circ.759
MARPOL Annex I
Shipboard oily-waste pollution-prevention procedure

Last reviewed: 2026-09-08