P: Is shipping nuclear steam generators through the great lakes waterway a good option?

To give you a little bit of background information, steam generators are as part of the nuclear steam supply portion of the CANDU (Canadian Deuturium Uranium) reactor design. Their purpose is to take heated heavy water (D20) and transfer that heat energy to light water (H20) to the point of vapourisation where it is then fed into a high and low pressure steam turbines in order to generate electricity. If you have taken heat transfer, this is an example of a heat exchanger, albeit a very large heat exchanger.

Steam generators in CANDU reactors weigh 100 tonnes and are as large as a 18 wheel truck and trailer, and with Bruce Power’s ongoing refurbishment of Units 1 and 2 of their Bruce ‘A’ generating facility, 16 used steam generators are currently sitting in the western waste management facility on the Bruce Power site.

So why does Bruce Power want to ship these used steam generators to Sweden for recycling? Well as mentioned, heavy water, from the reactor once flowed through these steam generators and, after around 20 years of service, slowly became slightly irradiated. As such, these steam generators are classified as low-level nuclear waste. Before you get all media poisoned anti-nuclear on this plan, the definition of low-level nuclear waste as defined by the Canada Nuclear Safety Commission (CNSC) is as follows: “In Canada, low-level waste is defined in the following manner: It does not require shielding during normal handling and transport. This is based on a dose rate criteria of two millisievert per hour or less, to distinguish between low and intermediate level radioactive waste.” You read that correctly, it does NOT require shielding during normal handling and transport.

Even though the steam generators are slightly irradiated, 90% of the whole generator still has usable metal and can be recycled, in fact, Duncan Hawthorne, CEO of Bruce Power, revealed in a CNSC hearing that only 4 grams of radioactive material is present in each steam generator for a total of 64 grams. Now as mentioned, 10% of the steam generators would still be classified as low-level waste as the internal tube bundles cannot be recycled and must be put back into storage. Let us go over the numbers, what’s better – 1600 tonnes of low level nuclear waste or 160? It’s Canada that is going to have to store the 160 tons of left over low-level waste, not Sweden, so what would you prefer?

Now, the plan is to ship them through the Great Lakes, out the St. Lawrence and across the Atlantic to Sweden. Ok, so the ship could sink, the ship could catch fire, and what else? Well not to confuse Bruce Power with the other BP, the amount of pollution and harm to the environment if any of these happened would be absolutely nothing like the Gulf Oil Spill. It’s like the difference between accidentally spilling a drop of oil in the ocean versus British Petroleum’s millions of barrels spilled.

First off, the ship being used to transport the steam generators is designed to transport Irradiated Nuclear Fuel. You wouldn’t even be able to come within one meter of irradiated fuel before getting immediate radiation poisoning causing death. Irradiated fuel bundles are kept under 3 meters of water as protection at Canadian CANDU sites, thus the ship is capable of transporting nuclear waste. Now if the ship sank, the sealed steam generators would still be intact, as they are built solidly to withstand high operating pressures of a nuclear reactor, thus they would survive a ship sinking. If said ship caught fire, the melting point of the steel is around 1500 degrees Celsius. With no combustible material available in the cargo hold of the ship to sustain such a high temperature, no fire would be able to penetrate the stainless steel sheathing and inner tubes. With no penetration of the steam generator, there would be no radioactive material release to the environment. The ship would likely sink before a fire penetrated the steam generators, and even if the steam generators would be submersed in a great lake or the ocean, the vast quantity of water would dilute any contamination to an untraceable amount before being recovered.

In Sweden, recycling nuclear steam generators is not new to Studsvik, the company contracted to do the work. In fact, the company has processed larger, more radioactive steam generators than the ones from Bruce Power.

Overall, the risk (barely any), is worth the benefit at greatly reducing the amount of nuclear waste on Canadian soil for our future generations, therefore, shipping the steam generators through the great lakes waterway, across the Atlantic to Sweden for processing is a good option.