The Coulombi Egg Oil Tanker - 2012 Study on the Safety, Economic and Environmental Issues of Double Hulls
Better protection, safer and more economical than Double Hull


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The US Department of Transportation seems to have doubts about double hull tankers as it, August 2012, plans to carry out a 

Study on the Safety, Economic and Environmental Issues of Double Hulls

Solicitation Number: EconStudy08062012 Notice Type: Sources Sought

The US Department of Transportation is now apparently looking for a Contractor to handle the study, where:

1. The Contractor shall conduct an assessment of the history in the evolvement of “The Double Hull Rules”.

2. The Contractor shall conduct the assessment of any rules that are being proposed in bodies such as the IMO, U.S. Congress and other such bodies’ worldwide as they relate to additional hulls for environmental reasons.

3. The Contractor shall assess all the relevant safety issues related to double hulls for each class of vessel. E.g. Double bottoms are difficult and expensive to maintain and can result in corrosion problems. Unchecked corrosion in older double hull vessels can lead to cargo leakage into a double bottom and the buildup of dangerous vapor which could cause an explosion under certain conditions. The Contractor will obtain data from appropriate organizations which details the issues in double bottoms on older vessels including cracking, leakage, and the potential for vapor buildup.

4. The Contractor shall conduct a complete economic study of the consequences of Double Hulls. E.g. they significantly add to the construction cost of vessels. They result in the loss of cargo space which also adds to the carbon footprint since an additional vessel(s) is needed to carry the same cargo tonnage.

5. The Contractor shall assess the complete consequences of the carbon footprint of designing, constructing, maintaining and operating vessels with double hulls. E.g. Apart from the extra propulsive forces and fuel needed, the carbon footprint of double hull maintenance is substantially increased.

6. The Contractor shall prepare a report on the results of the project. The report shall be grammatically correct and must be professionally written to a high level of competence in the English language. The report must clearly specify the safety, economic and environmental issues details above.

Reason for this study is:

"Following the Exxon Valdez disaster, the passing of the Oil Pollution Act of 1990 (OPA 90) led to the requirement to replace single hull petroleum tankers with double hull tank vessels sailing in U.S. waters. This requirement was soon adopted by the International Maritime Organization (IMO) and became a worldwide regulation."

It seems The US Department of Transportation has not got the facts right!

The IMO has early 1990's adoped Marpol rules about double hull, midheight deck and alternative design tankers (MARPOL Regulation 1/13F(5)) that can sail and operate anywhere, which the US also adopted but later, when the IMO approved the Coulombi Egg tanker design under these Regulations in September 1997, the US decided not to be a party to them. Therefore the Coulombi Egg tanker is approved by every member of the IMO except the USA that forbids them to enter US ports. The US is thus not a party to the IMO Marpol regulations (as it is all or nothing).

The matter have been discussed in the US Congress and could be resolved by the USCG and the The Coast Guard Authorization Act of 1998 but nothing was done.

Evidently the US unilateral actions have reduced maritime safety and environmental protection.

The above solicitation is full of errors:

Re 1 there are no “The Double Hull Rules”.

Re 2 there is only OPA90 (and USCG requirements) for US ships and MARPOL for all other ships (as US is not party to Marpol). OPA 90 requires additional double hull - MARPOL does not require additional double hull but permits midheight deck or one approved alternative; Coulombi Egg.

Re 3 the disadvantages of double hull are already known ... and history.

Re 4 and 5 investment and operation costs of a tanker depends on the standard and engines chosen and not the design type, e.g. double hull.

You really wonder what is the purpose of the project? That double hull tankers are not optimal? It has already been clarified 1997 when US decided not to be a party to Marpol 1.

It will be interesting to see what Contractor US DoT will appoint and the final report of the study.

Is US going to adopt MARPOL 1 again and accept Coulombi Egg tankers in US waters? (Aug 10, 2012)


No - The solicitation was cancelled in its entirety Sep 07, 2012 10:05 am at the convenience of the Government - probably due to Heiwa Co comments above.