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 Environmental Assessment Report #2
INITIAL ENVIRONMENTAL ASSESSMENT REPORT OF A SUPPLEMENTARY ELEMENT OF THE PROPOSAL TO RECOVER THE IRVING WHALE AND RECOVER ITS CARGO OF BUNKER "C" OIL.
REMOVING AND DISPOSING OF PCB MATERIAL FROM THE OIL CARGO HEATING SYSTEM OF THE BARGE. July, 1995
Foreward The barge "Irving Whale", loaded with 4200 long tons of Bunker C heavy fuel oil, sank on September 7, 1970 in the Gulf of Saint Lawrence 60 km northeast of North Point, PEI, in 67 Metres (220 ft) of water. The Departments of Transport and Environment conducted an environmental assessment of a proposal to recover the barge and its cargo as a pollution prevention measure in April, 1994. The federal government announced in August, 1994, its intention to proceed, as a pollution prevention measure, with the proposal to recover the barge, transport it to Mulgrave, Nova Scotia, recover its cargo of bunker C oil, clean the barge and sell or dispose of it in an environmentally acceptable manner. The final destination of the barge was subsequently changed to Halifax after negotiations between Canadian Coast Guard and Atlantic Towing Ltd. (ATL), an Irving owned company. More recently it was determined by the Canadian Coast Guard (CCG) (now part of the Department of Fisheries and Oceans) on June 23, 1995, in discussions with representatives of ATL, that a liquid material initially identified as "Monsanto MGS295S" in the closed-loop heating system of the barge, is a PCB. The liquid in the heating system was used to transfer heat to the cargo of Bunker C in the 8 tanks on the barge to keep the cargo liquid during transit to the unloading destination in Bathurst, New Brunswick. It is estimated that the heating system contained approximately 1,500 gallons (6,800 litres) of this PCB material. The potential significance of this information has been considered as a supplement to the initial environmental assessment of the proposal to recover the barge conducted in April, 1994. This supplementary environmental assessment has been carried out in accordance with the requirements of the 1984 EARP Guidelines Order (EARPGO), since the assessment of the proposal to recover the barge was initially commenced before the coming into force of the new Canadian Environmental Assessment Act. The EARPGO requires that every initiating department screen or assess each proposal for which it is the decision-making authority to determine potential adverse environmental effects, their significance and the extent to which they may be mitigated with known technology. This document presents the Initial Assessment Determination that has been made by the Department of Fisheries and Oceans - Canadian Coast Guard (DFO-CCG) and the Department of the Environment (DOE), the initiating departments, pursuant to Section 12 of the EARPGO relative to this proposal and provides the rationale for that determination. The Department of Fisheries and Oceans - Coast Guard is an initiating department since it will be directly undertaking the proposal pursuant to paragraph 6(a). Both DOE and DFO-CCG are initiators since they have made a financial commitment to the proposal pursuant to paragraph 6(c) of EARPGO. Specifically, it has been determined, pursuant to Section 12(c) of the EARPGO, that the potentially adverse environmental effects that may be caused by the proposal are insignificant or mitigable with known technology, in which case the proposal may proceed or proceed with the mitigation, as the case may be. However, a final decision on the proposal will not be made until the requirements of Sections 13 (gauging public concern) and 15 (access to the proposal and an opportunity to respond) of the EARPGO have been met. A period of 7 days after the public are advised of the determination will be allowed for comment on the supplementary element of the proposal. Notice of the initial assessment determination will be provided to the Irving Whale Public Advisory Committees on the Magdalen Islands and Prince Edward Island, as well as to the general public.
The barge "Irving Whale", loaded with 4200 long tons of Bunker C heavy fuel oil, sank on September 7, 1970 in the Gulf of Saint Lawrence 60 km northeast of North Point, PEI, in 67 Metres (220ft) of water (see Map). The Departments of Transport and Environment conducted an environmental assessment of a proposal to recover the barge and its cargo as a pollution prevention measure in April, 1994. The federal government announced in August, 1994, its intention to proceed with the proposal to recover the barge, transport it to Mulgrave, Nova Scotia, recover its cargo of bunker C oil, clean the barge and sell or dispose of it in an environmentally acceptable manner. This project is a pollution prevention move to mitigate against future pollution from the barge. The final destination of the barge was subsequently changed to Halifax after negotiations between Canadian Coast Guard and Irving representatives. It was determined by the Canadian Coast Guard (CCG) (now part of the Department of Fisheries and Oceans) on June 23, 1995 in discussions with representatives of Atlantic Towing Ltd. that a liquid material, initially identified as "Monsanto MGS295S" in the closed-loop heating system of the barge, is a PCB. It has further been established that the PCB is the substance known as Aroclor 1242. The liquid in the heating system was used to transfer heat to the cargo of Bunker C in the 8 tanks on the barge so that the cargo would remain liquid during transit. It is estimated that there is approximately 1,500 gallons (6,800 litres) of the PCB in the heating system. The presence of this PCB material on board the Irving Whale does not warrant a departure from the plan to recover the barge and its cargo as originally proposed, in fact, it underlines the need to remove the environmental hazard posed to the Gulf Of Saint Lawrence region by the Irving Whale. However, since this matter was not considered in the earlier environmental assessment, attention must now be given to the potential environmental effects that could result because of the presence of this PCB material and any measures which might be taken to remove and dispose of it in conjunction with the recovery of the barge and its cargo. This document briefly outlines the information that is currently available regarding the PCB material, its current whereabouts, options for its safe removal, measures for dealing with the material and a determination of whether there may be any potentially adverse environmental effects from the proposal (pursuant to Section 12 of the EARP Guidelines Order).
What is it? The material known as "Aroclor 1242", is a mobile, clear liquid which is relatively insoluble in and heavier than seawater. The chemical is similar to 1OW30 motor oil in fluidity. It readily separates from seawater and will not float on it. In an enclosed system, Aroclor 1242 is stable and will not degrade appreciably. When mixed with petroleum oils, including bunker, Aroclor 1242 will readily dissolve. It will adhere to or be adsorbed on sediment particles. While Aroclor 1242 has limited solubility in seawater, losses by dissolution may be significant over time. Aroclor 1242 will degrade faster than other higher molecular weight PCB mixtures through dissolution or microbial decomposition. Where is the PCB material now? The heating system would have ceased to operate during the sinking of the barge, on September 07, 1970. What damage the components of the heating system may have suffered during the sinking or during the 25 years the barge has been on the bottom of the Gulf of St. Lawrence is currently unknown. Efforts are underway to obtain additional information which may assist in determining the likely damage. However, based upon the latest chemical analyses carried out at Environment Canada's laboratory at the Bedford Institute of Oceanography, using archived sample material taken from various locations on the sea floor around the site of the barge in 1994, it has been concluded that some portion of the total quantity of the Aroclor 1242 has escaped from the heating system and now resides in the bottom sediments adjacent to the barge hull. The background concentration of PCBs in marine sediments are variable and usually depend upon proximity to land-based sources. North Atlantic sediment concentrations for open-ocean range from 0.3 to 44 parts per billion (ppb) while coastal sediments may be up to 1-2 parts per million (ppm) near more industrial areas. The total amount of PCB that has reached the bottom sediments or other components of the marine environment is not known at this time. In the absence of factual information to the contrary, DFO-CCG and DOE are, for the time being, operating on the assumption that most of the PCB liquid remains contained within the hull of the barge, although it may not necessarily be confined to the closed-loop heating system. The hull acts as a secondary barrier to all but the "ring" deck main piping which contains 260 gallons or 15% of the total quantity of fluid. As well, attempts are being made to identify the most likely locations of the PCB materials through the following measures:
The PCB is contained in a complex system of pipes and equipment. Most is in compartments inside the barge. Working in such spaces underwater is very dangerous and risks uncontrolled leaks of PCB into the environment. Experts recommend removing the remaining PCB when the barge is safely in Halifax. What are the environmental risks associated with the release of this PCB Material? Concern for PCBs in the marine environment relates to their tendency to persist, bioaccumulate and cause chronic toxicity effects. However, PCBs do not represent an acute hazard to aquatic organisms. A spill of the PCBs from the "Irving Whale" heat transfer equipment would, therefore, not result in any extensive or immediate toxicity for resident biota. Most nations, including Canada, have implemented regulations which are intended to prevent all releases to the environment. Under the Federal Toxic Substances Management Policy, PCBs in use are scheduled for virtual elimination. What would be the fate of PCB material spilled at the site of the "Whale"? If spilled, PCB material could add to the burden of PCB in the local aquatic community. Also, the chemical could eventually be mobilized and dispersed to a much wider area risking contamination of fish and benthic organisms. PCBs, in bottom sediments near the "Whale" could also continue to release this material for many years. What risk to human health does this PCB material pose? The risk to human health from exposure is low and can be addressed, where contact with concentrated amounts is planned, by the use of protective apparel while handling the material. The Chemical Evaluation Division, Health Canada, Halifax advises that the acceptable maximum PCB concentration in fish tissue to be consumed is 2 parts per million. Recovery Phase - Options for Dealing with the PCB Material, Associated Risks and Mitigation Measures The approach that will be taken to deal with the PCB material and the associated environmental risks will depend, to some degree, on the nature of the situation on the barge. Since elevated PCB concentrations have been found in sediments around the barge, it is assumed that the heating system has been breached and that some PCB leakage has occurred. Working from this assumption, several scenarios are possible:
Fate of the PCB: Due to its density, any leaked fluid will pool in the bilges. Mitigation:
As the material does not float, and will remain in the lower extremities of the spaces (the bilge), mitigation will be by removal in Halifax by qualified personnel.
Fate of the PCB: This situation could lead to contamination of the oil in the tank in which the breach occurs. Tank #1 and #2 have one heating loop whereas #3 and #4 have two loops, each loop contains 33 gallons. Each cargo tank contains a water pad between the bottom of the cargo and the bottom of the tank. If leakage developed prior to formation of water pad, the PCB would combine with the bunker C oil. If leakage developed after formation of water pad, the oil would sink and combine with the film (clingage) of oil on the bottom shell. In both cases, the oil and fluid are contained within the tank. Mitigation: All contaminated oil will be recovered in Halifax while the barge is in the Halifax Shipyards drydock.
Fate of the PCB: The PCB fluid is transported to the heating coils of each tank through an insulated ring main (supply and return) on each side of the barge. The ring main is attached to the outside of the cargo bin. If the ring main had been breached, the fluid flowed to the deck on the outside of the cargo bin and then to the ocean floor. Mitigation: The aft lifting sling will be positioned at frame Number 3. The main 4 inch diameter supply and return lines are located close to this area, particularly on the starboard side, and therefore, steps will be taken to ensure that these pipes are suitably protected from chafing or damage from the lifting slings during installation and lifting. Divers will be instructed to avoid damaging the exposed cargo heating pipes running along the length of the barge during removal of debris and while carrying out other activities associated with the recovery operation. Available construction documentation and comparisons with the barge "Irving Sealion" have been conducted and consultations with Atlantic Towing personnel familiar with the system have been held to learn as much as possible about the design characteristics of the barge. Each tank coil has isolation valves between the ring main and the deck. They would have been in the open position while in transit. Attempts to close these valves are not recommended unless it can be done without forcing, as the condition of the valves after 25 years underwater is not known. PCB from intact sections of the ring main will be recovered by qualified personnel in the drydock at Halifax.
Fate of the PCB: Leakage of PCB from damaged ring mains may have resulted in localized sediment contamination. Mitigation: Where technically feasible, contaminated sediments likely to be disturbed during the lift will be removed prior to the lifting of the barge. Sediment sampling following the lift will be carried out to further determine the extent and magnitude of sediment contamination as part of an evaluation of options for future remedial measures. In addition, in any of the above scenarios, the following mitigation measure will be employed: All efforts will be made to minimize disturbance of bottom sediments around the barge throughout all phases of the recover operation.
Measures to be Taken to Safely Remove, Store and Dispose of the PCB Material Once the barge arrives in Halifax aboard the submersible transport vessel, it will be carefully offloaded into the drydock at the Halifax Shipyards. While in the drydock, the barge will be secured and any PCB material on board will be removed by personnel trained in handling hazardous materials. The quantity of PCB material on board the vessel will be measured (to determine how much was lost into the marine environment to facilitate remediation efforts). This material will be stored in accordance with applicable federal and provincial legislation. The PCB material, and any PCB contaminated oil aboard the vessel (i.e., with a PCB concentration above 50 parts per million) will then be moved from Halifax, in accordance with the Transportation of Dangerous Goods Act, to a facility in Swan Hills, Alberta where it will be destroyed.
Measures to be Taken to Remediate the Site Interpretation of information obtained by the sampling and analysis of sediment, cargo oil and PCB trapped or remaining on the vessel, and a determination of the fate of PCB formerly contained in the cargo heating system will enable the remediation team to estimate the amount and disposition of the PCB remaining at the wreck site. Surveys of the sea floor in the vicinity of the barge will also be carried out to further determine the distribution of the contamination. Options for removal of any significantly contaminated material will then be assessed. In addition, as noted previously, every effort will be made to minimize further loss or disturbance of PCB contaminated sediments during the raising of the Irving Whale.
The potential significance of this information has been considered as a supplement to the initial environmental assessment of April, 1994. Based upon the information and evaluation presented in this document and related supporting materials, DFO-CCG and DOE have determined, pursuant to Section 12(c) of the EARPGO, that the potentially adverse environmental effects that may be caused by this proposal are insignificant or mitigable with known technology. The proposal, therefore, may proceed with mitigation. A final decision on the proposal will not be made until the requirements of Sections 13 (gauging public concern) and 15 (access to the proposal and an opportunity to respond) of the EARPGO have been met.
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