INTERNATIONAL MARITIME ORGANIZATION
E IMO
MARINE ENVIRONMENT PROTECTION COMMITTEE 59th session Agenda item 6
MEPC 59/6/9 8 May 2009 Original: ENGLISH
INTERPRETATIONS OF, AND AMENDMENTS TO, MARPOL INTERPRETATIONS AND RELATED INSTRUMENTS Proposed amendments to MARPOL Annex I – Improved cargo piping arrangements in order to transfer cargo into ballast tanks when a ship is in an emergency situation Submitted by the Republic of Korea SUMMARY Executive summary: summary:
This document proposes an amendment to MARPOL Annex I that is designed to improve cargo-piping arrangements in order to transfer cargo into ballast tanks when a ship is in an emergency situation
Strategic direction:
7.1
High-level action:
7.1.2
Planned output:
-
Action to be taken:
Paragraph 15
Related documents:
None
Introduction
1 This document proposes an amendment to MARPOL Annex I as a matter of new requirements for emergency piping arrangements which will reduce the amount of oil leakage by means of cargo transfer into ballast tanks when when a ship is in an emergency situation. These ships include fully loaded oil tankers which are leaking cargo caused by a collision or stranding and it has become impossible to conduct the operation of transferring cargo from a damaged tank into other fully loaded cargo tanks which are intact. Background
2 On 7 December 2007, two tugboats and a crane barge sailed toward the southern area of the Republic of of Korea under under heavy weather. The towing fleet was not able to maintain maintain its intended course and continued to drift south at 1.5 knots and approached the M/T Hebei Spirit (146,848 GT) which which was anchored. One of the tugboats’ towing wire snapped due to excessive
For reasons of economy, this document document is printed in a limited number. number. Delegates are kindly asked to bring their copies to meetings and not to request additional copies.
I:\MEPC\59\6-9.doc
MEPC 59/6/9
-2-
tension and although the tugboat dropped an emergency anchor, it collided with the ship. The collision resulted in three holes on the M/T Hebei Spirit’s port side and tanks Nos.1, 3 and 5 containing 12,547 kl of crude oil which leaked into the sea. 3 For this type of accident, the best way to minimize oil leakage into the sea is to transfer cargo to other intact cargo tanks. However, unfortunately, the M/T Hebei Spirit was already fully loaded with cargo including slop tanks and as a result of the tremendous amount of oil in the damaged tanks the oil leaked into the sea. 4 In this case, if the crude oil that was loaded in damaged tanks could have been transferred to other empty ballast tanks, it would have minimized oil pollution effectively. However, the cargo oil compartment was completely separated from the ballast water system in accordance with the requirements set out in regulation 1.18 of MARPOL Annex I and Unified Interpretation 3.1. Observations
5 As noted by all Member States, oil pollution resulting from a collision and/or stranding of an oil tanker, especially a single-hull tanker, causes severe damage. With reference to this matter, according to MARPOL Annex I, regulations 19 and 20, all oil tankers shall comply with the requirement of a double hull or double-bottom structure not later than the anniversary of the date of delivery of ship in the year 2010. In addition, MARPOL Annex I, regulation 23 on Accidental oil outflow performance, took effect on 1 January 2007. 6 However, in light of this accident, if a collision and/or stranding accident occurs to a fully loaded oil tanker complying with the requirement of MARPOL Annex I, regulation 18 on Protective location of segregated ballast spaces, segregation between the cargo piping and water ballast piping resulted in a severe problem for the transfer of oil cargo in the damaged cargo tank to a ballast tank. As a result, the amount of oil that spilled into the sea could not be reduced. Furthermore, it is only fair to mention that the same problem can happen to a double hull or a double-bottom oil tanker. Relevant MARPOL regulations and consideration of revision
7 With respect to the exception of MARPOL regulations, regulation 4 of MARPOL Annex I states that: “ Regulations 15 and 34 of this Annex shall not apply to: .1
the discharge into the sea of oil or oily mixture necessary for the purpose of securing the safety of a ship or saving life at sea; or
.2
the discharge into the sea of oil or oily mixture resulting from damage to a ship or its equipment:”
8 According to regulation 18.1 of MARPOL Annex I, every crude oil tanker of 20,000 tonnes deadweight and above and every product carrier of 30,000 tonnes deadweight and above delivered after 1 June 1982 shall be provided with segregated ballast tanks. With respect to exceptional cases to carry ballast water in cargo tanks, regulation 18.3 of MARPOL Annex I, as amended, states that:
I:\MEPC\59\6-9.doc
-3-
MEPC 59/6/9
“18.3 In no case shall ballast water be carried in cargo tanks, except: .1
on those rare voyages when weather conditions are so severe that, in the opinion of the master, it is necessary to carry additional ballast water in cargo tanks for the safety of the ship; and
.2
in exceptional cases where the particular character of the operation of an oil tanker renders it necessary to carry ballast water in excess of the quantity required under paragraph 2 of this regulation, provided that such operation of the oil tanker falls under the category of exceptional cases as established by the Organization.”
9 With respect to the definition of “segregated ballast”, the following unified interpretation of regulation 1.18 of MARPOL Annex I states that the segregated ballast system shall be separated from a cargo oil piping and a fuel oil piping system. However, it also provides that, in an emergency situation, the discharge of segregated ballast is possible through the connection of a spool piece to a cargo pump: “3.1
The segregated ballast system should be a system which is “completely separated from the cargo oil and fuel systems” as required by regulation 1.18. Nevertheless, provision may be made for emergency discharge of the segregated ballast by means of a connection to a cargo pump through a portable spool piece. In this case non-return valves should be fitted on the segregated ballast connections to prevent the passage of oil to the segregated ballast tanks. The portable spool piece should be mounted in a conspicuous position in the pump-room and a permanent notice restricting its use should be prominently displayed adjacent to it.”
Technical consideration for revision of current MARPOL regulations
10 Taking into account that the current regulations for control of discharge for oil possibly may not be applied in the event of discharge into the sea of oil resulting from damage to a ship, just as in the exceptional regulations as described in paragraph 7 above, we are of the opinion that to transfer oil loaded in damaged cargo tanks to vacant ballast tanks in order to minimize oil pollution is an appropriate measure. 11 In the MARPOL regulations as mentioned in paragraph 8 above, the ballast water could be carried in cargo tanks in spite of the requirements of segregated ballast water, if additional loading of ballast is necessary for securing the ship’s safety or characteristics of oil tankers. In this case, the ballast water should be discharged by means of a connection to a cargo pump through a portable spool piece in order to prevent oil pollution arising from any unexpected malfunction. After transferring the ballast water, the portable spool piece should be stored in the designated position of the pump-room. 12 In the same manner as above, we believe that it is a considerably appropriate measure to amend the relevant MARPOL regulations, as set out in the annex to this document, with the purpose of enabling the transfer of oil cargo from cargo tanks to vacant ballast tanks by using temporary piping arrangements, including a portable spool piece in the event in which emergency circumstances occur and such a measure is the best way to minimize oil pollution.
I:\MEPC\59\6-9.doc
MEPC 59/6/9
-4-
Proposal for emergency piping arrangements and transfer procedure
13 The proposed piping system is set out in figure 1 and figure 2 and this is used to transfer oil cargo from the cargo system to the ballast system in an emergency. Stop valves and spool pieces are installed as well as the access gate of the ballast piping system for the connection with cargo pipes are installed.
Figure 1 – Piping system with a cargo pump-room
I:\MEPC\59\6-9.doc
-5-
MEPC 59/6/9
Figure 2 – Piping system with a deep well cargo pump
14
The procedure for transferring oil cargo to the ballast tanks should be as follows: .1
before transferring oil to the ballast tanks, the safety and stability of the ship’s structure that is expected after transferring the oil should be checked;
.2
before transferring oil in emergency, the ballast tank should be made inactive by injecting an inert gas (in cases in which an inert gas generator is installed). Also, the air vent head in the ballast tank should be checked in order to prevent pressure from increasing inside the ballast tank; and
.3
the open/close valve status should be thoroughly checked at the cargo control room before transferring the oil cargo.
Action requested of the Committee
15 The Committee is invited to consider the proposed amendments to MARPOL Annex I as presented in the annex to this document and take action as deemed appropriate. *** I:\MEPC\59\6-9.doc
MEPC 59/6/9
ANNEX PROPOSED AMENDMENTS TO MARPOL ANNEX I
1 It is suggested that a new paragraph 8 is added to regulation 30 of MARPOL Annex I and its unified interpretation below should be written as follows: Regulation 30 – Pumping, piping and discharge arrangement
“8 Oil tankers of 20,000 tonnes deadweight and above constructed on or after [1 January 2013] should be equipped with a means capable of connecting to ballast tanks from cargo oil systems, even if those should be separated under normal circumstances, in order to transfer oil cargo into the ballast tanks in a state of emergency arising from damage to oil cargo tanks due to a high energy collision. And oil tankers of 20,000 tonnes deadweight and above constructed before [1 January 2013] should be equipped with a means capable of connecting to ballast tanks from cargo oil systems, even if those should be separated at ordinary times, in order to transfer oil cargo into the ballast tanks in a state of emergency as a consequence of collision damage to oil cargo tanks, by the date of the first scheduled dry-docking after [1 January 2013], but not later than [1 January 2016].” Unified interpretation to regulation 30.8 of MARPOL Annex I
“ Examples of means to enable connecting to ballast tanks from cargo oil systems is to place non-return valves in the way of cargo oil system to ballast system and stop valves and a spool piece at the outlet pipe line from cargo oil pumps. The spool piece should be kept on the disconnected condition at all times except in emergency cases, such as a collision damage to cargo oil tanks, and it should be in control of the master or the officer in charge of cargo operations. In addition, a caution notice written as “This should not be used except in the emergency case of discharge into the sea of oil or oily mixture resulting from collision damage to cargo oil tanks” should be prominently displayed adjacent to the spool piece.”
2 It is suggested that a new paragraph 3.2 for interpretation to regulation 1.18 of MARPOL Annex I should be added as per the following text below: Unified interpretation to regulation 1.18 of MARPOL Annex I
“ Paragraph 3.2 should now become paragraph 3.3. ” A new paragraph 3.2 is added: “3.2
I:\MEPC\59\6-9.doc
In spite of the provision whereby the segregated ballast system should be completely separated from the cargo oil and fuel systems, as required by regulation 1.18, it may be allowed to be connected with a portable spool
MEPC 59/6/9 ANNEX Page 2 piece to transfer oil cargo from an oil cargo system to a ballast water system in an emergency for the purpose of preventing or minimizing oil spillage into the sea after the occurrence of damage caused by a collision. In this case, non-return valves should be fitted on the cargo oil piping system to prevent the passage of ballast water to cargo oil tanks. The portable spool piece should be mounted in a conspicuous position in the pump-room and a permanent notice restricting its use should be prominently displayed adjacent to it.”
___________
I:\MEPC\59\6-9.doc
