Risks of a Nuclear Waste Disposal Facility

Norman Rubin
Borealis Energy Research Association on behalf of Energy Probe
August 8, 1995

Part 2 of Energy Probe’s Submission on The Adequacy of Atomic Energy of Canada Limited’s Environmental Impact Statement on the Concept for Disposal of Canada’s Nuclear Fuel Waste. Submitted to the Federal Environmental Assessment Review Panel.


In September 1994, Atomic Energy of Canada Limited (AECL) completed its Environmental Impact Statement on the Concept for Disposal of Canada’s Nuclear Fuel Waste (the “EIS”). The following month marked the beginning of a nine-month review of how adequately that EIS addresses the issues raised in the Federal Environmental Assessment Review Panel’s Final Guidelines for the Preparation of an Environmental Impact Statement on the Nuclear Fuel Waste Management and Disposal Concept (the “Guidelines”). As part of that review, Energy Probe retained Borealis Energy Research Association as a consultant to examine risk methodology and criteria.

In describing the first phase of work, Energy Probe asked Borealis to review the EIS and supporting documentation and to comment on its behalf on the adequacy of its treatment of risk methodology and criteria. Energy Probe advised Borealis to focus especially on the following areas:
(1) total population, individual, and environmental risks, especially due to radioactive substances that may be released from the envisaged repository (Guidelines, pages 10-11), including the risks of human health impacts such as “additional cancers” (Guidelines, page 55);
(2) the criteria that relate to those risks (Guidelines, pages 13, 18, and 20, etc.);
(3) the definitions of safety and acceptability (Guidelines, pages 9, 11); and
(4) adequate proof of safety (Guidelines, page 11).
The following report provides that review and Energy Probe’s comments. In general, it documents multiple and systematic failures on AECL’s part to produce the information requested in the Guidelines. Indeed (as documented below), AECL’s EIS in the areas of risk methodology and criteria seems essentially to be a response to the regulatory documents of the Atomic Energy Control Board (AECB), rather than a response to the Federal Environmental Assessment Review Panel’s Guidelines. As a result, AECL’s review of risk methodology and criteria is an inadequate basis for meaningful public hearings on its proposed concept. (Despite Energy Probe’s serious concerns with several aspects of this Federal Environmental Assessment Review process, it does constitute a process that is far more modern, enlightened, and responsive to the public than any process the AECB has ever initiated — including the process that gave rise to AECB’s three regulatory documents on nuclear fuel waste disposal (R-71, R-72, and R-104). As a result, it is extremely important that this Panel ensure that the concept for geological nuclear fuel waste disposal is tested against the Panel’s own guidelines, and not merely the essentially “self-regulatory” requirements of the AECB.)

As requested by the Panel, this report refrains from commenting on the merits of the opinions and conclusions of the EIS, as opposed to its sufficiency to form the basis of public hearings. Accordingly, the absence of critical remarks herein should not be mistaken for endorsement of AECL’s opinions and conclusions.

It must be noted that funding for intervenors in this review has been extremely limited, and will not permit public-interest intervenors to provide the kind of expert evidence necessary to remedy the inadequacies documented below. It is therefore essential that these inadequacies be corrected before any more effort is spent on the review of the merits of the opinions and conclusions of the EIS.

General Recommendation: The Panel should insist that all identified inadequacies are corrected before any more effort is spent on the review of the merits of the opinions and conclusions of the EIS.
General comment on the structure and presentation of the EIS documents:

The organization of the EIS documents, including the EIS volume itself, is completely different from the organization of the Guidelines, on which it should be based. (See EIS, pp. 12-13, “Unusual Aspects of this Review and this EIS”.) Supposedly as mitigation of this offense, AECL has provided, in Appendix A of the EIS, “a cross-reference that indicates where items in the guidelines are addressed in the EIS [EIS, p. 13]”. Unfortunately, that 4-page cross-reference is totally inadequate to repair the deficiencies caused by AECL’s disregard of the structure and logic of the Panel’s Guidelines. For example, in searching for AECL’s discussion of “risk on the basis of total population” from the reference disposal system (Guidelines, §3.2, p. 10, discussed directly below), the reader (including the Panel!) is directed to search through Sections 2.2.9, 3.2, and 3.4.3 of the EIS, and Chapters 6, 7, and 9, and Appendix H in their entirety! As discussed below, that discussion is apparently not contained in any of those 135-odd pages, or anywhere in the companion volume The Disposal of Canada’s Nuclear Fuel Waste: Postclosure Assessment of a Reference System (henceforth, “R-Postclosure”).
The extent to which the deficiencies of AECL’s EIS documents are the result of its decision to ignore the Guidelines’ structure remains a subject for conjecture; however, the difficulties that decision poses to readers, intervenors, and the Panel itself — both in assessing the documents’ deficiencies and in locating the answers to specific questions asked in the Guidelines — are real and significant.

Recommendation: The Panel must direct AECL to respond directly to the Guidelines — either by preparing a new “companion” document based on the structure of the Guidelines or by beginning over, with the structure and content of the Guidelines in mind. To prevent the squandering of the precious resources of the Panel and public-interest intervenors, the Panel must not progress toward a hearing until that work is completed and judged sufficient.
General concerns regarding the future of the process:

It is a feature of this FEARO review of this concept that the developer of the concept and the author of the EIS documents (AECL) will not necessarily be the proponent or “implementing organization” of the actual management or disposal of nuclear wastes. AECL leaves the issue officially open in its discussion of the implementing organization (EIS, pp. 79-80), but also claims that it is essential to maintain AECL’s own “team” if Canada is to avoid losing a $400 million asset. (See “The Potential Loss of Technology”, EIS pp. 76-77.) Energy Probe’s contrary view on the selection of an implementing organization is also a matter of public record, and was presented to this Panel in the Scoping and Guidelines stage of this process. We continue to believe that AECL, given its mandate, its management, its history, its current priorities, and its corporate culture, is unlikely to succeed at the task of finding a publicly acceptable solution to the problems it has so aggressively promoted. Now, in light of the pervasive and apparently willful nature of many of the deficiencies in AECL’s documents (as documented below), we would suggest that the Panel consider, or urge the federal government to consider, the possibility that further investment of public funds in AECL, to remedy this deficient Environmental Impact Statement, will prove a bad investment.
Total population, individual, and environmental risks

Total population risk has not been estimated, discussed, or controlled.
The Panel directed AECL to “discuss and, where possible, quantify the risks to the health of humans and human communities . . . that are associated with the concept . . . This discussion should include . . . the following: risk on the basis of total population and the individual; . . . [Guidelines, p. 10; italics added]”. In this regard, the Panel was significantly more responsive to public concerns than the Atomic Energy Control Board, which neither discusses nor regulates the total population risk from a nuclear waste repository in its three relevant Regulatory Documents (R-71, R-72, and R-104).

Unfortunately, AECL has ignored the Panel’s direction, apparently without even mentioning it. We have only located one passage in the EIS that even remotely or indirectly discusses the decision to ignore the Panel’s direction: Pages 17-19 in R-Postclosure quote the basic guidelines in AECB’s Regulatory Document R-104 (cited in R-Postclosure as “AECB 1987a”). These guidelines refer specifically and repeatedly to “the individual of concern” or to “individual risk requirements”, and never refer to risk on the basis of total population. AECL’s first two sentences immediately after the quotations from R-104 are as follows:

The postclosure assessment of the reference disposal system includes an estimate of the radiological risk that complies with these four guidelines.

Much of our analysis is focussed on estimates of a variable that is measurable: annual dose to members of the critical group.

It must be pointed out that — despite AECL’s use of the plural word “members”, and despite its frequent avoidance of the word “individual” — what AECL calls “a variable that is measurable” is the dose (and from the dose, the health risk) to an individual member of the critical group. (According to the discussion and Figure D-54 in R-Postclosure, p. 502, the median-value size of the critical group is three persons.) All the text, charts, and graphs of “Estimated Mean Annual Dose [Sv/a]” or of “annual dose estimate [ADE]” in AECL’s submissions, covering hundreds of pages, refer only to the dose to an individual member of the critical group, and not to the collective dose or risk on the basis of total population.

This omission is extremely unfortunate, because it makes many extremely important decisions, tradeoffs, and ethical dilemmas simply vanish from view — and from the EIS documents. For example, the SYVAC model, operating only on individual dose and risk, “proves” that contaminating a well that provides drinking water for three people is far worse than contaminating a lake that serves many more people. The lake is larger, providing more dilution and therefore a lower dose to the individual. In reality, the expected total harm to humans would presumably be greater from the lake contamination, but apparently AECL hasn’t asked its staff to use the model to answer that question. (Virtually identical comments could be made about AECL’s “proof” in R-Postclosure, pp. 490-502, that the predicted annual dose decreases as the number of people drinking from a contaminated well increases.)
Similarly, the question of how far from human population concentrations to site a nuclear waste repository is a very important issue that trades off cost versus population risk, but not necessarily individual risk. To take an extreme example: A repository in downtown Toronto would most likely show lower individual doses and risks than the reference repository near Whiteshell: nobody in Toronto drinks well water, and poisons leaching out of the repository would soon reach Lake Ontario, whose enormous volume would provide significant dilution. The fact that millions of people would be put at risk, increasing the total population dose and total harm, simply does not appear from the models, as run by AECL. (AECB’s Regulatory Documents would also apparently permit urban or suburban siting of a repository — ironic because AECB’s Regulatory Documents for reactor siting place limits on total population dose!)

The totally absurd discussion of the impacts of urbanization on the discharge site (in R-Postclosure, p. 56, table 4-1) shows a “real-life” example of how AECL’s (and AECB’s) elimination of this basic and common-sense consideration can lead to sheer idiocy: “Although the discharge site could become urbanized, it is reasonable to expect that overestimates of impact [i.e., dose to the individual!] would always be obtained by assuming the discharge site is rural (Davis et al. 1993). . . . Because impacts are estimated for the group at most risk (the critical group), it is conservative to assume that they have the characteristics of a rural group and that the discharge site is rural.”

Recommendation: The Panel must, once again, direct AECL to model the collective dose or risk on the basis of total population. All the screenings, simulations, sensitivity analyses, design constraints, optimizations, etc., done with the SYVAC computer model must be redone, “on the basis of [both] total population and the individual”.
The potential for additional cancers has not been presented. (But the individual risk of fatal cancer has been deficiently represented.)

Throughout the EIS and R-Postclosure, the estimated radiation doses from the “reference system” repository — given only in terms of individual radiation doses, as discussed above — are translated into what AECL calls “the probability of a health effect”. This translation is a deficient response to the Guidelines in at least two ways:

 As AECL explains (e.g., EIS, p. 297), the very inclusive-sounding “a health effect” actually includes only fatal cancers or serious genetic effects. There is no attempt made to estimate the non-fatal cancers (or non-fatal genetic effects) that the planned repository will cause. Thus, for example, the graphs in Figure 7-7 and Figure 7-9 in the EIS volume (pp. 297 and 299) purport to show “Risk (probability of an individual incurring a health effect/a)” as a function of time, but do no such thing. Any suggestion that an AECL-induced non-fatal cancer is not a health effect is a deficiency in common English usage and common decency, as well as in responding to the Guidelines. (E.g., Guidelines, page 55, directs AECL that “Potential impacts should be expressed in terms that are readily understandable, such as: . . . the potential for additional cancers.”)

 The risks (only individual) of cancer (only fatal) are intentionally underestimated throughout, “as specified by the AECB in R-104 (Appendix B), using 0.02 as the probability of a health effect (fatal cancer or serious genetic effect) per sievert. [EIS, p. 297]” Since 1987 (the date of the AECB’s R-104), both ICRP and AECB have replaced that risk factor with one that is several times higher (as is acknowledged deep in Appendix H, EIS p. 460). Even in a submission to AECB (which this entire AECL submission resembles, but should not), the use of an obsolete, non-conservative risk factor would be a deficiency; in a submission to a FEARO panel, it is absurdly deficient.

Of course, the omission of any calculation of collective risk on the basis of total population, as discussed above, compounds these two deficiencies.
Criteria that relate to risks, and the definitions of safety and acceptability

In Guidelines § 5, page 13, the Panel requires AECL to develop “adequate long-term performance criteria . . . for each of the components of the system, and for the system as a whole. A comparison with regulatory criteria . . . should also be provided.” Guidelines § 5.13, page 18, refers more specifically to “criteria for abandonment or rejection of a vault or sections of a vault . . . “, while Guidelines § 5.2, page 20, refers to the analogous “criteria for the rejection of a rock mass . . . “. Based on our reading of two of AECL’s volumes (the EIS and R-Postclosure), AECL has not developed any long-term performance criteria, adequate or otherwise, at least for the system as a whole. Nor has it provided the requested “comparison with regulatory criteria.” Rather, it has circularly defined “safe” to mean no more than “permitted by regulations”, as follows:
We define safe as meeting criteria, guidelines and standards for protecting the health of humans and non-human biota. Criteria, guidelines, and standards for the protection of human health and the natural environment are specified in legislation, regulatory documents issued by the AECB, and guidelines, as described in Appendix B. Some may also be specified in the licenses issued by the AECB. (EIS, p. 63; “safe” is similarly defined in the Glossary, p. 495.)

The apparently total lack of independent criteria is clearly at odds with the Panel’s direction in the Guidelines sections quoted above. Further, it substitutes narrow and lax regulatory scrutiny by the “industry-friendly” AECB for the much broader scrutiny of an independently appointed, and more broadly representative, Federal Environmental Assessment Review Panel. Finally, by primarily “working backwards” from a computer-model-estimated radiation dose to a future individual, it places far too much emphasis on computer modelling of the repository, which is highly uncertain and error-prone, and also highly dependent on a specific site and therefore beyond the scope of this Panel. This Panel has before it only the “for instance” results of computer modelling of a “reference system”, modeled on a site near the Whiteshell Nuclear Research Establishment in Manitoba — a province with no nuclear generating stations and legislation prohibiting the disposal of out-of-province nuclear wastes.

In addition to the Panel’s own clear direction in the Guidelines sections quoted above, we would remind the Panel, and AECL, of Energy Probe’s long-term views on this topic, as presented in the Scoping and Guidelines phase of this Review:
 What minimum “performance criteria” and how many are appropriate for the decision to bury high level nuclear waste? What levels for these criteria does AECL propose?
. . .
 To what extent should deterministic (“pass fail”, “disqualifying”, or “drop dead”) criteria be applied in the process of site screening or selection? Which such criteria does AECL propose using?
(Energy Probe’s October 22, 1990 submission, p. 2)

We have found several brief references to the notion of “acceptable risk”, but no definition, as requested on p. 9 of the Guidelines.
Adequate proof of safety

Guidelines, page 11, calls on AECL to discuss not only “a definition of safety in relation to the concept”, but also “an outline of what would constitute adequate proof of safety.” Although the documents contain several references to the (inadequate) provisions of the AECB’s Document R-104, we can find no such outline.
Other deficiencies
Possible fissioning of weapons-grade Plutonium
The Panel directed AECL to discuss “the possible changes in the nature and characteristics of nuclear fuel waste due to changes in nuclear power technology or in energy policies (Guidelines, page 4)”, as well as the effect of changes in nuclear technology on the amount of nuclear fuel waste (Guidelines, page 8). One change in nuclear power technology which is currently being proposed by Ontario Hydro and AECL to the U.S. government is the fissioning, in Canada (probably at the Bruce-A Nuclear Generating Station) of fuel containing weapons-grade Plutonium from U.S., or possibly former Soviet, nuclear weapons. Reportedly, the preferred option being proposed by Ontario Hydro and AECL involves the operation of the Bruce-A Nuclear Generating Station for many years longer than is currently planned by Ontario Hydro. Further, in all current proposals discussed in public, the resulting nuclear fuel waste would remain in Canada. This proposal could therefore change both the quantity and the nature and characteristics of the nuclear fuel waste awaiting disposal in Canada. The EIS documents do not discuss these changes, or their impact on the concept.
“Postclosure” retrieval of buried nuclear fuel waste

In Guidelines, §3.3, page 11, “Retrieval of Buried Nuclear Fuel Waste”, the Panel directed AECL as follows:
The EIS should outline plans and procedures which would be required for the retrieval of nuclear fuel waste from a sealed and decommissioned disposal vault under emergency or other circumstances. This should include estimates of the cost of such an operation . . .
Appendix A of the EIS volume refers to two sections in that volume as addressing this topic: § 3.6.6, “Retrievability”, and § 5.8.9, “Waste Retrieval” (EIS, pp. 72-72 and p. 199). Neither provides the cost estimates specified in the Guidelines. Further, the description of “the reference disposal vault” on pp. 42-43 of R-Postclosure makes no mention of the topic at all.
Erroneous exclusion of Chlorine-36 from estimated doses and risks.

Perhaps the most striking error which AECL committed and subsequently detected is the erroneous exclusion of Chlorine-36 from the list of radionuclides of concern. (See EIS p. 315, and R-Postclosure pp. 266-7.) Originally thought to be too insignificant to be included among the 68 radionuclides of concern, it may well turn out to be the single most important cause of modelled long-term radiation dose. (In the EIS documents, AECL only acknowledges that its contribution could be “comparable to radiation doses resulting from Iodine-129”. Of course, Iodine-129 totally dominates the repository’s estimated long-term radiation dose to individuals. (See, e.g., Figures ES-4 and 6-4 in R-Postclosure pp. xiii and 153: “The largest contributor is 129I; in fact, the curve of its ADE [annual dose estimate] coincides with the curve for total ADE.”)

This error, and others that have recently been discovered, should be rectified before this assessment proceeds to a hearing.
The EIS and its models must either use plausible data or the EIS must explain why not.
Through a chance coincidence, explained in a footnote to Table 6-2 on page 166 of R-Postclosure, readers of AECL’s documents can discover that the plant/soil model used in SYVAC contains a discontinuity which, we presume, is not reflected in the reality of plants and soil. We are in no position to examine all of SYVAC’s input data for similarly implausible “artifacts”, and doubt that the Panel or its Scientific Review Group is, either. Accordingly, either we must all simply distrust the integrity of AECL’s data in general, or the job must fall to AECL to indicate where there are physically implausible discontinuities in their data because of the simple combination of algorithms. Preferably, AECL would do further research to reconcile the two algorithms at their boundaries. The Panel must assure that AECL rectifies each of these deficiencies in one way or the other.
The discussion in EIS §3.10, “Timing of Disposal”, does not take account of the information on EIS page 38, concerning “trends in the setting of safety standards”.

Page 38 indicates (and we agree) that there is a trend toward more protective safety standards (either in general or for radioactive contamination in particular), as well as a trend for “new biological information” to increase the risk factors for radiation. Accordingly, there may well be a clear benefit to future populations from delaying the disposal of these radioactive wastes, until standards have become more protective. AECL should be directed to connect these two issues, and also to address the issue of evolving standards in its discussion of alternatives to the concept that delay burial

Read Norm Rubin’s Bio

This entry was posted in Nuclear Power, Nuclear Safety, Power Generation in Ontario. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s