Simon Daigle lists the public concerns that must be addressed in planned development of BWRX-300 small nuclear reactors – Submission to Canadian Nuclear Safety Commission

Submission Concerning the Proposed Development of BWRX-300 – multiple reactors at the Darlington Site (Ontario)

Submitted November 19,2023 by Simon J Daigle, Simon J Daigle, B.Sc., M.Sc., M.Sc(A) Montreal, Quebec Canada

 Response to the proposed development of OPGs BWRX-300 reactors at the Darlington CANDU reactors site and the items below are all real public concerns and must all be addressed independently and individually, as per the following categories:

CNSC licensing of the BWRX-300 reactors & Multiple Reactors nearby a NPP is inadequate [References: 1, 2, 4, 5]

• BWRX-300 stands for Boiling Water Reactor eXperimental 300 and developed by GE Hitachi Nuclear Energy (GEH) and will not aim to address any key challenges faced by traditional nuclear power plants. In fact, they will be costly, and generate extremely toxic nuclear wastes more than what would be expected by traditional NPP plants. [Ref. 4].
• This experimental compact design will not reduce construction costs, will not simplify operation nearby one NPP, or will ever enhanced safety measures. In fact, it will do the exact opposite as per IAEA [Ref. 1 and 5].
• It is questionable to say the least that by utilizing natural circulation and passive safety systems you will eliminate the need for external pumps and active cooling mechanisms because during a meltdown, fire or catastrophic event (lightening, flooding, extreme air temperatures over decades because of climate change), who will shut it off? A worker? I’m more reassured when a Pilot on commercial flight is present when he or she is using the auto-pilot function [Ref. 1].

• CNSC license to built an experimental reactor based on the CNSC’s decision that OPG has met the recommendations of the 2011 Environmental Assessment Report by the JRP is not objectively verifiable or can be validated based on the 2023 Update report [Ref. 2].
• No objective evidence is available to validate what specific recommendations of the JRP have been adopted, analysed and/or implemented by OPG or CNSC. [Ref. 2].
• No BWRX-300 reactors are operating anywhere in the world and is a real public concern for the citizens living nearby as well as the potential impacts of a catastrophic environmental event that could be transboundary across many municipalities.

Engineering Design Risks: Experimental, Natural water cooling & neutron leakage [4,5].

• Water cannot be used to cool a reactor as it is experimental design reactor that will use use low pressure water to remove heat from the core. A distinct feature of this reactor design is that water is circulated within the core by natural circulation and yet no data is measured or validated by any laboratory confirmed analysis or modelling study.
• Neutron leakage will be problematic for any SMR design as well as for  the BRMX-300 reactor as no proof of any safe SMR reactor system can be validated or compared too to this very day.

• This is no experimental data to elude or conclude that this experimental reactor will work in terms of an internal cooling system of the core.
• BWRX-300 is by all means not small as it covers a full football field.
• No BWRX-300 reactors are operating anywhere in the world.
• The proposed design and operation of a BWRX-300 is entirely different from the CANDU design and involves a structure and a method of operating which is, in large part, below ground level.
• No data on any potential meltdown of the core of any modular nuclear including BWRX-300 including catastrophic events cascading located nearby a Nuclear Power Plant.
• Neutron leakage is a huge problem with SMRs and will be as well with the BWRX-300.

• SMR Neutronics and Design: [Ref. 4].
  • “A nuclear reactor is designed to sustain criticality, a chain reaction of fission events that generates energy (∼200 MeV per fission event) and extra neutrons that can cause fission in nearby fissile nuclides.
  • The neutron “economy” of a reactor depends on the efficiency of the chain reaction process; the fate of neutrons absorbed by abundant nuclides, such as 238U or 232Th; the fission of newly generated fissile nuclides, such as 239Pu and 233U; and the loss of neutrons across the fuel boundary.
  • These “lost” neutrons can activate structural materials that surround the fuel assemblies. Each of these physical processes generates radioactive waste.
  • Thus, the final composition of the SNF and associated wastes depend on the initial composition of the fuel, the physical design of the fuel, burnup, and the types of structural materials of the reactor.
  • The probability of neutron leakage is a function of the reactor dimensions and the neutron diffusion length, the latter of which is determined by the neutron scattering properties of the fuel, coolant, moderator, and structural materials in the reactor core.
  • The neutron diffusion length will be the same in reactors that use similar fuel cycles and fuel–coolant–moderator combinations; thus, the neutron leakage probability will be larger for an SMR than for a larger reactor of a similar type.”
• Public Consultation, indigenous peoples and social acceptability: [Ref. 2].
• No objective evidence has been elucidated or clearly documented with transparency.
• EIA Impact statement: page 84 of [Ref. 2].
• EIA impact statement, nor final PPE parameters, did not follow IAEA Multi-Unit Probabilistic Safety Assessment required for 1 or 4 experimental reactors nearby a Nuclear Power Plant despite the fact that EIA significance analysis had assessed all the residual adverse effects [Ref. 1, 5]. Please refer to the list of EIA and PPE selected quotes below as the reference to compare with the IAEA Multi-Unit Probabilistic Safety Assessment that is lacking [Ref. 1, 5].

• 
  EIA and PPE selected quotes:

“EIS significance analysis had assessed all the residual adverse effects to be “Not Significant”. Of the likely residual adverse effects that were forwarded for assessment of significance in the EIS:

• Seven (7) were also determined to result in minor residual adverse effects from the BWRX-300 but less than that described in the EIS,

• Four (4) were not applicable to the BWRX-300 reactor,

• Five (5) were determined to have residual adverse effects not significant after completion of additional studies to assess the likely effects to retained terrestrial features not considered in the EIS.

• The PPE Of the 198 PPE parameters, 60 PPE parameters were not applicable to the BWRX-300. Of the 138 applicable PPE parameters evaluated, eight (8) BWRX-300 parameters are currently not within their respective PPE parameters. These are largely due to characteristics inherent to the design of the GEH reactor technology. These eight parameters are related to the following topics:
  • The rate of fire protection water withdrawal and the quantity of water in storage,
  • Deeper foundations (38 m below grade) than the reactors previously assessed in the EIS (13.5 m),
  • Airborne releases of radioactive contaminants and normal operation minimum release height above finished grade,
  • The different proportions of radionuclides in solid wastes generated by the operation of the BWRX-300,
  • The weight of the cask used to transport the BWRX-300 spent fuel on site, and
  • The multiplication factors applied to basic wind speed to develop the plant design.
• A full environmental impact assessment is required to fulfill provincial and federal jurisdiction best practices for air, water and soil & biosphere impacts during a catastrophic event or meltdown of this experimental reactor as well as maritime and lake biosphere impacts.

Nuclear accidents, incidents, multiple explosion risks or 1 or 4 BMRX-300 reactors nearby a NPP, Soil Stability, hydrogeology, lithospheric & seismic Risks: [Ref. 1,2, 5].

• No objective risk assessment has been completed by OPG or CNSC as per the required IAEA Multi-Unit Probabilistic Safety Assessment required for 1 or 4 experimental reactors nearby a Nuclear Power Plant. [Ref. 1,5].
• The appropriateness of building 1 or 4 untested reactors next to the 4 existing CANDUs at Darlington as well as the current and potential stored nuclear waste is questionable given the fact that the probabilistic safety assessment was not completed according to the IAEA methodology [Ref. 1]. 
• JRP recommendations concerning the physical conditions of the Darlington site need to be applied with transparency by OPG and the CNSC. [Ref. 2].

Other public and safety concerns: these issues need to be addressed

• Climate change impacts have not been included in the EIS report.
• Unknown:  reliability data to reduce the risk of potential accidents.
• Unknown:  demonstrating that the BMRX-300 is a clean and reliable source of electricity, capable of generating vast amounts of energy without producing greenhouse gas emissions as it is only an experimental design.
• Concerns surrounding safety, waste disposal, and cost have hindered its widespread adoption globally. A handful of countries have adopted this design but no data on the true financial costs to governments or to that taxpayer. [Ref. 4].

Unknown: BWRX-300 did not address safety concerns, efficiency, efficacy as a cost-effective alternative compared to renewables such as hydro, solar or wind energy generation.

• 
  Unknown: sustainability and reliability compared to wind and solar energies to meet the growing demand for electricity.
• BWRX-300 represents a significant step backwards in power technology. It is not compact, it does not meet nuclear wastes (as per the IAEA ALARA principle) that will last for thousands of years, and most certainly, it is not cost effective over time to store and monitor SMR or BWRX-300 nuclear wastes based on the probability of any heat instability of the nuclear core over time and the generation of highly toxic nuclear waste. You cannot turn off radioactivity like an electrical light bulb as there are no fuse switch off for ionizing radiation.