EAB DECISION: NOTRE DEVELOPMENT CORPORATION EA-97-01
UNCERTAINTY AND RISK OF 1000 YEARS CONTAMINATING LIFESPAN
The contaminating lifespan of the Adams Mine landfill, as outlined in 3.1.3. of the majority decision,
is estimated by the proponent to be about 1000 years. This extimate was generally accepted but Mr. Bowen
did point out that it was far from precise since it was arrived at by using computer modelling based on actual
landfill data covering a period of only 10-30 years. (Exhibit #65, Coalition Panel 1 Witness Statement, p.5)
This means that although the landfill will accept waste for only 20 years, at a projected rate of 1 million tonnes
per year, the engineered leachate collection and containment system will have to continue to operate for 1000 years to
make sure that contaminants don't escape from the pit into surrounding water resources.
This 1000 year contaminating lifespan is an important factor because it heightens the importance of each of the 5 following
areas of concern since each concern will continue over such a long term.
POSSIBLE FAILURE OF THE DRAINAGE LAYER
As outlined in 3.1.4 of the majority decision all the engineered components must have a service life of 1000 years to match
the contaminating lifespan of 1000 years. Most of the engineered components can be replaced so the only relevant factors are cost and
financial assurance.
However, as outlined in 4.1.2.3 of the majority decision, the service life of the drainage layer becomes a crucial issue since it is
fundamental to the hydraulic containment design and it cannot be replaced once it is buried under tonnes of waste.
Mr. Bowen pointed out the proponent's estimate of the effects of clogging was arrived at using computer modelling based on laboratory
experiments and very short term actual landfill experience raising doubts about its accuracy. (Transcript, Vol. 10, p.67, pp.69-71 and
pp.223-24. Transcript, Vol.11, pp.15-18 and p.129)
Dr. Barone said the proponent's estimate of a 3000 year service life for the drainage layer was based on "...calculations for the rate of
clogging which look at the growth of a film consisting of bacteria and calcium carbonate. And the reason for this very large lifespan
of the drainage system is very simple, it's because again it's a large size stone, it's very large volume of stone, and it has a very low flow
rate going through it, 32 gallons per minute."(Transcript, Vol5,pp.30-33)
On the question of clogging of the drainage layer, I question Dr. Barone's assertion that the drainage blanket will "never clog" and his
estimate of a service life of 3000 years.(Transcript, Vol.4,pp.190-91, pp.194-95, Transcript, Vol.5, p.79)
I prefer the more cautious approach taken by Mr. Bowen: "I think it's a very real risk. It's one that has not been addressed sufficiently and the most important issue arising out of
that risk is that there's an absolute necessity to clearly identify the costs and feasibility of the contingency works as an upfront
issue with respect to landfill design...You can make assumptions, you can look at what has happened at other sites and you can come up with some
very, very approximate timeframes, but what it ultimately leads me to conclude is that there will be clogging of the system." (Transcript, Vol.10, p.74; Transcript, Vol.11,p.25)
Although he does not have the academic qualifications of the expert witnesses, all of whom, including Mr. Bowen, disagreed with his analysis,
Stan Gorzalcynski, a mechanical technologist, who specializes in the design of material haulage and transport systems in the aggregate and mining
industries made a very convincing presentation, using the proponents calculations, to suggest the shear forces from the settling of the waste could
seriously damage the drainage layer thereby causing a failure of hydraulic containment and the subsequent escape of leachate. (Exhibits 14 and 25; Transcript, Vol2,
pp.85-126; Transcript Vol.12, pp.48-49)
I believe there is enough evidence to suggest the drainage layer could fil over the 1000 year contaminating life span leading to a failure of
hydraulic containment and the subsequent migration of leachate out of the pit.
INADEQUATE MONITORING
I agree with my colleagues conclusions, as outlined in 4.1.2.3 of the majority decision, that the
monitoring program suggested by the proponent, and agreed to by the Ministry, has been significantly
improved as a result of concerns raised by Mr. Bowen throughout the hearing.
I feel it is still deficient in terms of monitoring beneath the pit and the large interval distance
between groundwater monitoring wells along the south side of the pit. As a result it will not warn
of the escape of leachate from the pit in the event of loss of hydraulic containment.
The proponent's expert hydrogeologist, Mr. McFarland, confirms this concern.
Q. If there's a leachate pathway, fractures, whatever, either in the upper 30 metre zone or in the upper
100 metre zone..if these monitoring wells are not hydraulically connected to the pathways, is it possible
that the leachage could slip through in this interval distance?
A. That's correct.(Transcript, Vol.6,p.195)
I believe that because of the nature of the site (fractured bedrock, structures, variable conductivity)
it is impractical to effectively monitor groundwater for migration of leachate out
of the pit and for water levels indicating variabl conductivity under the pit and this concern
will remain for the 1000 year contaminating lifespan of the project.
LACK OF DESIGN DETAIL ON CONTINGENCY PLANS
Because of the lack of natural protection at this site, because of the proponent's 100 percent
reliance on engineered works over the 1000 year contaminating lifespan of the lanfill and
because of concerns raised about possible failure of hydraulic containment, the effectiveness
(technical and financial feasibility) of contingency measures becomes a crucial concern.
The proponent has identified several possible contingency plans such as purge wells, an interceptor
trench and the resumption of pumping during the drainage phase but, in Mr. Bowen's opinion, they
have not provided the level of design detail required to assess their effectiveness. In our opinion, it is necessary to provide more detailed information and, in particular,
establish the potential long term costs and operational implications of the above
contingency measures. It is of particular importance given the extended period of time
(several hundred years) over which the leachate collection will be necessary. Without properly
identifying the detailed design and potential costs of the above measures, it will be
difficult to provde a reasonable basis for assessing the financial assurance matters." (Exhibit #65,
Coalition Panel 1 Witness Statement, p7)
The majority decision concludes in Part C-Financial Assurance, Explanation that while the proponent's
contingency plans have not proceeded beyond the conceptual stage, a combination of the 5-step
Predictive MOnitoring and Response Plan and the financial assurance condition that requires 10 percent
of the total contingency fund be accumulated in the first two years of operation (and thereafter in proportion
to the filling of the site) would allow a contingency plan to be put in effect within the predicted time (about one year)
it would take escaping leachate to reach the south boundary of the property in the event of loss of hydraulic containment.
I believe the lack of design detail on contingency plans and the resulting lack of financial assurance information is not as
crucial as earlier concerns but it is a part of the hydraulic containment design package and is important for a complete understanding
of that package.
FINANCIAL ASSURANCE INFORMATION
As outlined in Section 2 of the majority decision (An Issue of Jurisdiction-Financial Assurance), the proponent brought a
motion for a ruling that financial assurance and financial matters be declared outside the jurisdiction of the Board and that
Coalition evidence on financial matters be declared inadmissible. The Board issued a unanimous ruling that financial
assurance was within our jurisdiction as long as it related to the central question of hydraulic containment design but that
due to the stringent timelines it would not be practical for a detailed costing exercise. The Board stated that it would be
in a position, based upon insights derived from this process, to set out conditions containing principles and guidelines related
explicity to the leachate management system that would be helpful to the Director in formulating an appropriate and effective
Financial Assurance Plan.
Mr. Bowen argued for the coalition that in order for the Board to judge the effectiveness of the engineered components it must
consider the technical feasibility (can you do it?) and the financial feasibility (can you afford to do it?). A proposal may be
technically feasible but if you can't afford to do it, then it can't be said to be effective. (transcript, Vol.10, pp.228-29;
Transcript, Vol.11 pp.158-59).
Mr. Bowen Argues the financial assurance information is inadequate in three areas.
1)Long term operating costs for engineered works are not available.
2)Costs for the contingency plans are not available; and
3)inherent difficulty predicting rate of return on funds set aside over the 1000 year contaminating lifespan.
(exhibit #65, Coalition Panel 1 Witness Statement, pp.7-8)
The Board did accept as evidence, and listen to arguments on, financial information regarding:
1)A proposed Financial Assurance Plan
2)Financial Assurance Contingency Allowance Calculations as they relate to hypothetical early closure scenarios; and,
3)Estimated costs of building an interceptor trench as a contingency plan for loss of hydraulic containment. (Exhibits #84, 88 and 101)
Given the stringent timelines imposed on the hearing it was not practical to engage in a detailed costing exercise but I agree with Mr. Bowen
more financial information would have allowed the Board to better judge the effectiveness of the engineered works and contingencies
that are an integral part of the hydraulic containment design.
GROUNDWATER LEVELS IN THE DEEP ANGLED BOREHOLE BENEATH THE PIT
This is the same concern that I mentioned earlier in the section on monitoring
but I concur with the majority decision that it is of crucial importance and deserves to be dealt with separately.
Section 4.1.2.1 of the majority decision outlines in some detail the importance of further study of the
fractured bedrock beneath the pit to be certain there are no geological features (dykes, faults) that could serve as
a pathway for leachate flow out of the pit when there is less inward flow pressure during the drainage phase when the pit is allowed to fill up.
The evidence on the anomalous low water level reading from the deep angled borehole and the opinions of the proponent
and of Mr. Bowen for the coaltion are clearly and fairly set out in sections 4.1.2.1. and 4.1.2.2. of the majority decision.
I am totally in agreement with my colleagues in their analysis of this issue. I disagree with their solution because,
notwithstanding Mr. Bowen's conclusion, I don't believe 2 more deep angled boreholes beneath a 27 hectare pit, sited in fractured bedrock with
possible fault and dykes, is sufficient to effectively monitor groundwater levels that may indicate loss of hydraulic containment during the gravity phase.
CONCLUSION
When I weigh the totality of the evidence presented on all the above concerns (uncertainty and risk of a 1000 year contaminating lifespan, possible failure
of the drainage layer, inadequate monitoring, lack of design detail on contingency plans and the resulting lack of financial assurance information and uncertain
groundwater levels beneath the pit) I come to the conclusion that enough concerns have been raised that a proper exercise of the precautionary principle would
lead us to say no to this project.
Having regard to all the above concerns it is my considered opinion the proponent has not fulfilled the onus placed on it to demonstrate the effectiveness
of the proposed hydraulic containment design, consistent with the requirements of the Environmental Assessment Act.
Dated at Toronto this 19th day of June, 1998
Don Smith, Member
