February 13, 1994
Dear Dr. Goldberg:
Concerned Citizens of Renfrew County (CCRC) is dedicated to the protection of human health and the environment. We are pleased to submit the following comments related to the proposed interim drinking water objective for tritium.
CCRC's recommendation is that the tritium standards for drinking water be reduced substantially below the proposed standard of 7,000 Bq/L. Ontario should match or exceed the highest drinking water safety standards in the world. It is inappropriate to take small incremental steps towards drinking water safety. The goal should be zero discharge for compounds such as tritium that are known carcinogens. Recognizing that it will take time to achieve this goal, we recommend that interim standards achieve at least a 100-fold reduction in the maximum allowable tritium concentration in drinking water, i.e., from the current 40,000 Bq/L to less than 400 Bq/L.
To provide a rationale for this recommendation, we would like to take this opportunity to provide some background information on the rather unusual current situation regarding releases of tritium and other waste isotopes in our area. Renfrew County currently has the largest accumulation of radioactive wastes (in terms of total activity) of any location in Canada. These are found at the Chalk River Laboratories of Atomic Energy of Canada, Ltd. (AECL).
Additional wastes are continually generated by AECL's ongoing operations. AECL's medical isotope production facility generates high level liquid radioactive wastes that are stored on site. The ancient NRU reactor used to generate the highly irradiated fuel rods that provide the molybdenum-99 feedstock for medical isotopes is highly polluting, emitting far more tritium, carbon-14, radioiodine, argon-41 and other radioactive compounds than modern reactors with a comparable power output. Radioactive wastes are routinely released into the air through roof vents on a large number of buildings and from two tall stacks: the 50-m exhaust stack from the NRU reactor, and the 61-m exhaust stack for the molybdenum-99 production facility.
The cooling system for the NRU reactor is highly unusual. Water is drawn at an average rate of 1.6 m3/sec directly from the Ottawa River through the heat exchangers of the reactor. Waste water contaminated with tritium is then released back into the river through AECL's "process sewer". Various other radioactive contaminants (activation and fission products) are also released into the river. Several other sources of liquid radioactive effluent discharge also exist at the Chalk River site: the sanitary and storm sewers, and two watersheds (Maskinonge/Chalk Lake, and Perch Creek) that are heavily contaminated by leachate from radioactive waste dumps.
Chalk River is a dumping ground for wastes imported from other parts of Canada. AECL operates a commercial waste disposal facility that routine accepts shipments of low level wastes from hospitals, universities, industrial generators, and so forth. AECL is now actively engaged in a federally sponsored process that may lead to transshipment of about one million tonnes of radioactive wastes and contaminated soil from the Port Hope area to its Chalk River property. Apart from these imported wastes, a large number of self-generated wastes have been dumped on AECL property, including those originating from the partial meltdown of the original NRX reactor in the early 1950's.
CCRC members have been speaking out (to little effect) against this onslaught of radioactive wastes for over 15 years. Renfrew County's air, lands, and waters have been seriously contaminated by radioactive substances released from AECL's Chalk River "laboratories". The waste disposal philosophy at Chalk River has been, and continues to be, "dilution is the solution to pollution". It is fair to say that there is also an ongoing cover-up of the magnitude of releases of radioactivity from Chalk River, and the health consequences of these releases.
Historically, AECL Chalk River has been "self-regulated", operating within the derived release limits (DRL's) calculated by Palmer in 1981. Permissible releases are based on the yearly dose likely to be received by an individual at the AECL property boundary, 6 km from the stacks. It is assumed that airborne radioactive wastes are diluted by a factor of a half-billion at this distance. More precisely, it is assumed that if radioactive wastes are emitted in a flow volume of 1 m3/sec from the stacks, they will be dispersed into a flow volume of 500,000,000 m3/sec at the property boundary. The actual flow rate from the stacks is in the range of 3-12 m3/sec. There are also separate DRL's for plant workers, stricter than those for the general public. Although plant workers are permitted higher annual exposures than the public, this is outweighed in the calculation of worker DRL's by lower dilution factors in the immediate vicinity of the point of release (e.g., roof vents near ground level).
In a separate document (attached), I discuss some of the problems with this regulatory framework in the context of air emissions. Briefly, this framework fails to consider either the accumulation of radioisotopes over the lifetime of an exposed individual, or the collective dose received by all persons living downstream and/or downwind of AECL Chalk River. Furthermore, each individual facility at AECL is treated as an independent unit for regulatory purposes. While releases from each individual facility generally remain well below the DRL's, no attempt is made to sum the total release from all facilities in operation, which may be considerable. So permissive are the tritium DRL's for many facilities that it is literally impossible to exceed them for any conceivable accident, whatever its magnitude (see below).
The federal Atomic Energy Control Board (AECB) has recently begun to assert some regulatory oversight over AECL Chalk River. For example, an AECB Staff Annual Report on Chalk River dated May 26, 1992 (AECB 1992) documents the poor performance of the NRU reactor in the two previous years: unacceptable numbers of reactor trips, safety violations, operator-related reportable incidents, lost time accidents, high average doses to exposed workers, airborne tritium releases at 12% of the DRL (based on limits for plant workers). It is obvious that concerns for worker safety at the Chalk River facilities are so great that no serious considerable can be given to the health and safety of the general public. In a recent conversation with Canada's most noted authority on radioactive waste regulation, Dr. Richard Osborne of AECL, I confirmed that he has never attempted to calculate the collective public health impacts of radiation released by the Chalk River facilities.
The work of your committee is concerned with drinking water standards for tritium, so it is more relevant to discuss the regulatory framework for aquatic releases at Chalk River. Again, the assumption is that dilution is the solution to pollution: the large average flow (750 m3/sec) of the Ottawa River will dilute releases to relatively low levels before they reach the intake at Petawawa about 20 km downstream (Palmer 1981). Note that the process sewer from the NRU reactor has a flow rate of 1.6 m3/sec, so the effective dilution factor is only around 470. Please note also that the use of the average flow rate to calculate dilution of this waste stream is mathematically incorrect. The flow of the Ottawa River is highly variable, and the yearly average flow is biased upwards by large discharges during spring snow melt. It would be more appropriate to calculate the dilution factor from the lower medianflowlevel.
Besides carrying waste cooling water from the NRU reactor, the process sewer at AECL Chalk River also discharges wastes from a heavy water upgrading plant and from a waste treatment centre. Monitoring of the waste stream in the process sewer is inadequate, and leaks can go undetected for days. For example, it was estimated that approximately 150 trillion Bq of tritium were released from an electrolytic fuel cell (35% of the total in the unit) at the heavy water upgrading plant in late May and early June 1991. Although this sounds like a large leak, it was not detected for several days, and was not even considered to be a reportable incident under the operating license for Chalk River "because release of the full inventory of the unit would not have caused the DRL to be exceeded" (AECB 1992).
The regulatory framework for releases of tritium and other radioactive substances from AECL Chalk River is wholly unacceptable. Monitoring of the process sewer is not adequate to detect relatively serious accidents. Available data on radiation releases are either classified or reported as "annual totals" that do not permit an accurate accounting of flow rates, volumes, and concentrations. Little consideration is given to the health and safety of downstream communities. No consideration has ever been given to the fact that millions of people draw their water for drinking, cooking, bathing, etc. from points downstream of AECL Chalk River.
Given this abysmal situation, any serious efforts at provincial oversight would be highly welcome. If the Advisory Committee on Environmental Standards were to propose a 100-fold tightening of drinking water standards for tritium:
We recognize that such a significant improvement in drinking water standards for tritium will meet significant resistance, and that some existing facilities might not be in compliance with these standards. Nonetheless, we feel that the best strategy is to recognize that a problem exists and exert the maximum public pressure to solve it. The alternative approach of arguing over "acceptable levels of risk" and "phased reductions" in tritium releases is morally indefensible and will merely lead to continued waste of scarce public resources.
On behalf of Concerned Citizens of Renfrew County, I would like to express my thanks to you and the other members of your committee for your efforts to set the highest possible standards for environmental protection in Ontario.
Sincerely yours,
Ole Hendrickson
References:
AECB. 1992. AECB staff annual report on Chalk River Laboratories and Whiteshell Laboratories. BMD 92-117. Atomic Energy Control Board, Ottawa.
Palmer, J.F. 1981. Derived release limits (DRL's) for airborne and
liquid effluents from the Chalk River Nuclear Laboratories during normal
operations. AECL-7243. Atomic Energy of Canada Limited, Chalk River, Ontario.