• Abstract and Figures
• Public Full-text

THE GROUNDING OF THE IMPERIAL ST. CLAIR- A CASE HISTORY OF CONTENDING WITH OIL IN ICE Capt. C. J. Beckett Canadian Coast Guard Central Region, Transport Canada Downloaded from http://meridian.allenpress.com/iosc/article-pdf/1979/1/371/1738288/2169-3358-1979-1-371.pdf by guest on 28 September 2021 Toronto, Ontario, Canada M5E1E5 ABSTRACT: During mid-morning on December 23, 1976, the oil the seaway, these ice strengthened vessels could be transferred to the products tanker Imperial St. Clair, carrying over 10,400 tons of cargo, work of re-supplying the Canadian Arctic grounded in the approaches to Parry Sound. Located on the eastern With the advent of winter navigation in the Great Lakes it was evi- shores of Georgian Bay in Lake Huron, this port is a central depot dent that only particular vessels would be able to navigate the frozen supplying a large hinterland with petroleum. lakes and that cargoes would have to be quite selective. Consequently, At the time of grounding, new winter ice was present in varying the older vessels selected for use where navigation was possible in the thicknesses and temperatures and winds varied from day to day, carriage of high grade ores were generally the "hard nosers." These resulting in very difficult conditions in which to effect operations. were vessels built with a single stem bar not rounded and "soft" as An estimated 57,000 gallons of diesel fuel and gasoline was lost dur- many of the new bulk carriers. New vessels were designed with heavier ing the initial impact and later during oil transfer operations. The plating and stronger beams in the bows, along the water line, and at methods used to boom off the remaining oil through the winter period the stern. Other considerations were taken into account such as pro- accounted for almost 40,000 gallons of the remainder. tection to propeller and rudder, adequate shaft horse power to push This paper deals with the chronology of events after the grounding, through ice fields and winterized accommodations for crews. the problems encountered with the safety of personnel, methodology The motor tanker Imperial St. Clair is a fitting example of this new of removal under ice conditions and the logistics of the operation. The breed of vessels. Built in 1974 as a company vessel to carry a variety of result was total success, thus safeguarding one of the most beautiful different petroleum or chemical products, her hull was built to ice areas of the Great Lakes. class 1 specifications. She is powered by a diesel engine developing about 6,500 shaft horse power using a variable pitch propeller. Although capable of carrying about 100,000 barrels of oil as a full cargo, the Imperial St. Clair was loaded in Sarnia, Ontario, in mid- December 1976 to 75% of her capacity, bringing her draft to about 22 The designed purpose of the present St. Lawrence Seaway, which feet in fresh water. Her cargo was of mixed petroleum products opened in 1959, was to provide ocean access to the Great Lakes system destined in part for the port of Parry Sound, Ontario, on the eastern on an eight-month basis. A major engineering undertaking between lake shore of Georgian Bay in Lake Hu/on. the United States and Canada, the seaway was predicted to attract a Parry Sound is one of the selected ports in the upper Great Lakes two-way movement of shipping with an original forecast of about 50 which serves as a distribution center. Four major petroleum producing million long tons. At the close of navigation late each fall it was ex- companies have large tank farms in the port and serve a large pected that a marginal movement of some vessels would occur until ice hinterland which stretches as far east as the Abitibi area in western conditions impeded further traffic. Quebec. Entrance to the port from Georgian Bay is made along some However, the economy of the hinterland expanded rapidly and ton- 25 miles of channels between islands and across open bodies of water. nages moved rose with the demand. As a result, the season increased The area is a prime tourist center in all seasons, particularly summer, to one of eight-and-one-half months officially, with extensions and many year-round residents occupy homes on the islands guarding granted by seaway authorities in either spring or fall, depending on the approaches. weather and water temperatures. Furthermore, the movement after the close of the season of con- sumable cargoes by vessels within the upper lakes of Huron, Michigan and Superior presented a very attractive proposition. This area, Grounding of the Imperial St. Clair although not ice free by any means, was not restricted by a series of locks as in the Weiland Canal or St. Lawrence Seaway, with the excep- The Imperial St. Clair arrived off the approaches to the channel in tion of the U.S. locks at Sault Ste. Marie, Michigan. the early morning of December 23, 1976. The master decided, due to During the mid-1960's and 1970's, several shipping companies were heavy snow, to anchor until full daylight and improved visibility. rebuilding their fleets along different lines. Previous vessels were Shortly after 0800 hours, conditions had improved, providing clear designed to ply their trade in ice-free waters, limiting their seasonal visibility along the channel, sufficient that the outer ranges were visi- operation both inland and on the east coast, particularly where ble at nine miles. In order to obtain the most recent report on weather domestic cargoes were concerned. But the demand for particular inside the sound, the vessel contacted the Canadian Coast Guard base products was rising along ice-infested waters particularly where towns by radio telephone. were expanding and population centers increasing. Other methods As the vessel proceeded in on various courses, further snow squalls were initially used to transport petroleum products but the carnage of set in, reducing visibility to nil. About an hour after entering the chan- these cargoes by water was both economical and generally unrestricted nel, the vessel entered new ice which did not reduce its speed by specially built vessels. This method of transportation would also significantly. Approximately half an hour later, heavier ice was en- reduce the need to increase stockpiles in major ports which would re- countered which brought the speed down to less than seven knots. quire further capital layout for new tanks as demand increased. Dur- Shortly before 1000 hrs the Imperial St. Clair grounded forward on ing the summer months, when conventional vessels could be used in a shoal patch known as Telegram Rock (Figure 1). 371 372 1979 OIL SPILL CONFERENCE Downloaded from http://meridian.allenpress.com/iosc/article-pdf/1979/1/371/1738288/2169-3358-1979-1-371.pdf by guest on 28 September 2021 wM&i£r^7i^ Figure 1. Hydrographie chart of approaches to Parry Sound showing areas in which the Imperial St. Clair first grounded and was offloaded Recognizing that the vessel had ruptured tanks in the bow and ap- spread out up to 150 feet from the bow and a strong smell of gasoline peared to be leaking gasoline and possibly diesel or home heating oil, and diesel was observed. Contact was made with the captain of the St. the captain contacted the Canadian Coast Guard Base in Parry Clair to inform him of the unsafe ice conditions and the heavy and Sound. possibly explosive odor that prevailed in the area, making it unsafe for the helicopter to land. The report from the vessel was that transfer of tanks of diesel fuel from the No. 1 center tank was being effected as Actions taken after the grounding far as possible to allow a "water bottom" to be placed in the tanks, so preventing further loss. At this time, the Canadian Coast Guard's contingency plan for Imperial Oil Limited dispatched a team of four officers to Parry marine emergencies in the central region was enacted, and the Ontario Sound to assist in the operations. In conference at company head- region's major oil spill contingency plan was activated by Imperial Oil quarters it was determined that efforts should be made to do the Limited in Toronto. following: refloat the St. Clair, prevent further product loss, contain Immediate contact was established between both groups, opera- the loss if possible, and effect transfer and delivery of product to tionally lead by Capt. J. Kennedy, Canadian Coast Guard Base, Parry Parry Sound as expeditiously as possible. These decisions were relayed Sound, and J. A. Sproule, Imperial Oil environmental adviser, To- to the Parry Sound Coast Guard base. ronto. Coast Guard dispatched a helicopter from the Parry Sound The Coast Guard, recognizing that the need could arise for a heavy base to effect an initial overflight and also recalled the navigational duty pump to transfer the product, requested a six-inch submersible aids tender CCGS Montmorency from Midland, Ontario, to standby pump and accessories to be brought in immediately from Prescott. in case of necessity. The base itself was put on a red alert and the Pres- The unit would be shipped on board the CCGS Montmorency at Parry cott Coast Guard Base on the St. Lawrence River brought to a yellow Sound and then transferred with an operator to the St. Clair, where it alert condition. would be rigged and able to operate if internal pumping facilities The first reconnaissance flights established the exact location of the could not effect the operation. vessel, the spreading of the oil from the bow area and the thickness of The vessel brought in by the company to assist in the off-loading the ice in the immediate vicinity.

Load more

  6

Copy Link