The oil-like sub­stance leak­ing from the over­turned barge off the Cove, To­ba­go, since Feb­ru­ary 7 has been iden­ti­fied as an “in­ter­me­di­ate fu­el oil”, ac­cord­ing to the Min­istry of En­er­gy and En­er­gy In­dus­tries (MEEI) and the In­sti­tute of Ma­rine Af­fairs (IMA).

The min­istry ex­plained in in­dus­tri­al ap­pli­ca­tions, an ‘in­ter­me­di­ate fu­el oil’ is al­so called “bunker fu­el”, which is the col­lo­qui­al term for fu­el oil used by ma­rine ves­sels. The MEEI al­so said that fu­el oils are a class of oils used in ocean ves­sels made from re­fin­ing crude oil and blend­ing with re­fin­ery dis­til­lates.

Ear­li­er this week, pre­lim­i­nary test­ing from the IMA sug­gest­ed the sam­ples tak­en were char­ac­ter­is­tic of “re­fined oil, pos­si­bly a fu­el oil or ma­rine diesel”. These ini­tial test re­sults were made pub­lic by the To­ba­go House of As­sem­bly Chief Sec­re­tary Far­ley Au­gus­tine and of­fi­cial cor­re­spon­dence from the Min­istry of For­eign and Cari­com Af­fairs, which was al­so sent to in­ter­na­tion­al part­ners such as Grena­da’s gov­ern­ment.

Au­gus­tine said then, “They (IMA) are com­ing back to do ad­di­tion­al taps, and that is why the re­mote-op­er­at­ed ve­hi­cle (ROV) is work­ing to­day. We could lo­cate the best place to do the tap. Even the last sam­ple they re­ceived had some el­e­ments of sea­wa­ter in it.”

Those sam­ples were even­tu­al­ly tak­en, and ac­cord­ing to the MEEI, this new iden­ti­fi­ca­tion re­sult­ed from the pre­lim­i­nary fin­ger­print­ing re­ports from the IMA based on sam­ples tak­en from the shore­line at Ca­noe Bay, To­ba­go, 200 me­tres near the cap­sized ves­sel.

Be­cause many dif­fer­ent types of oil ex­ist, of­fi­cials may need to tell one oil from an­oth­er dur­ing a spill. The chem­i­cal com­po­si­tion of oil found in the en­vi­ron­ment yields im­por­tant clues about its ori­gin. This process of de­ter­min­ing where a sam­ple of oil (or hy­dro­car­bon residue) orig­i­nat­ed is called “fin­ger­print­ing”.

The IMA said it used “Gas Chro­matog­ra­phy-Mass Spec­trom­e­try (GC-MS)”, and analy­ses of the hy­dro­car­bon dis­charge col­lect­ed in To­ba­go in­di­cat­ed that the sam­ples are char­ac­ter­is­tic of re­fined oil.