Monday, June 29, 2015

City's Stay Application Strength Challenged


Follows is a Facebook post by Mr. Cliff Marcil who has assisted the CDPPS technical committee but actually withdrew from the committee in disagreement with the way the committee was going to function. 

It would appear that Mr. Marcil raises enough questions about the process to date, to not give comfort to the decision to spend millions and millions of tax dollars based on the city staff-led technical committee results.

Follows are my comments regarding the Order and the City's stay and appeal. It is difficult for me to understand why some or all of these points were not made in the City's Stay Application and it is my view that the Stay Application is not as strong as it could have been had some of these comments been added:

1. I believe the timelines imposed by the Comptroller’s Order are not only unreasonable but are also unrealistic and impossible to meet. It could be hazardous (environmentally and safety-wise) to be in the mid-point of construction and have to stop due to weather or closed fisheries conditions. In my view this time-line is irresponsible and poses a much greater risk by attempting to complete remediation work this year. As late as February 2015 City staff were of the opinion that work could not be completed this year if a decision was not made almost immediately.

2. These dams have stood for more than 105 years with no factual evidence of ever overtopping. This was confirmed by Golder in their DSR Report of 2003. What possible risk could there be that would compel the Water Comptroller to force the City to carry out remediation instead of engaging in further diligence in such limited timelines? I contend therefore that the urgency and scheduling of remediation work to be unnecessarily harsh, unreasonable, and unwise.

3. The latest classification of the Lower Dam was deemed to be Very High; however as part of the further diligence process the City should conduct further study and analysis to confirm this conclusion, since, amongst other reasons, I believe that the environmental consequences of any dam failure have not been assessed on an incremental basis. This is the proper methodology to establish dam classification for these criteria as per the CDA Guidelines. I can find no details in the Golder Reports that would confirm that Golder did indeed perform the assessment of consequential environmental damages based on an Incremental Basis as per the CDA Guidelines. In order to do so an environmental assessment would have been required to determine what the consequences of an IDF flood event would be without the dams failing to establish a baseline and again I find no such information or evidence of this kind of assessment being completed by Golder.

4. I believe that DSS personnel have acted in an unprofessional manner, and may have failed to apply the required and expected degree of diligence in reviewing previous reports -such as the previous DSR’s and particularly the Associated Engineering Inundation Report of 2012. This contained several assumptions and speculative conclusions; consequently DSS personnel issued several letters to the City and even to a local newspaper claiming that up to 150 fatalities could result from the failure of the dams in an earthquake mode of failure. I believe that this is now a prime motivation factor in forcing the City to implement expensive and intrusive remediation options, despite evidence showing that the dams are not of danger in the event of an earthquake. The conclusions reached in the AE 2012 were prima facie questioned by laypeople in Nanaimo who were familiar with the dams and park, and these conclusions have been effectively shown to be exaggerated and or incorrect in Golder’s more recent reports.

5. The Comptroller appears to have failed or neglected to consider that the Owner of the dams is a City Corporation (Municipal Government); as such the City has a duty to be diligent, accountable and transparent in all of its dealings related to the dams. The City owes duty to taxpayers to ensure that proper diligence is carried out before rushing into a remediation option which could prove to be a) not required and b) not the ideal remediation.

6. From reports I believe that the City has spent approximately $3 million on engineering reports to date and according to Council’s last resolution the City needs reasonable additional time to carry out more investigation and analyses to ensure that remediation will be minimally intrusive. This would include minimizing the possible effect any chosen remediation option may have on not only the park but also on the flow levels for the lower Chase River.

7. Not only have the dams never overtopped in their 105 year history but also the Inflow Design Flood to which the lower spillway is being ordered by the Water Comptroller to be upgraded to is a 1 in 34,000 year flood event! It strikes me as absurd that the flood hazard is based on an extrapolated 1 in 34,000 year event yet the Water Comptroller is ordering the City to proceed with a remediation option on an urgent and claimed imminent safety hazard all the while knowing that the engineering diligence has not been completed. A stay and or a revised order as may be decided by the Environmental Appeal Board would allow the City through a Committee to complete the work (studies/research) that was never finished with the objective to answer the question – “What is the actual flood performance of the dams” - A solution can only truly be defined by a proper understanding of the problem.

8. In his letter of January 23, 2015, the Comptroller of Water Rights wrote the following to the City of Nanaimo: “On October 29, 2012, the City of Nanaimo provided a plan to address the safety hazards identified at that time. To date, that plan has not been implemented. Please note that although the dam failure consequence classification of both Middle Chase River Dam and Lower Chase River Dam is now set at a lower classification than previous, both dams still have serious deficiencies that require immediate attention.”

The insistence that the City still meet a plan provided under very different states of knowledge and circumstances seems to be unreasonable. It is my understanding that further Risk Analysis and Studies performed by Golder after October 2012 have greatly lowered the seismic risk and that no lives would be lost due to a seismic failure. This is very different than the context under which the urgent schedule was originally crafted since the previous Associated Engineering report had concluded the seismic hazard to be extreme (i.e. up to 150 people could be killed as a consequence when the dams would fail in a seismic event) This reduced risk is confirmed in the Golder reports and again in the Golder’s Consequence Classification letter of November 21, 2014 to the City which said: “The risk of failure of the dams due to earthquakes was extensively evaluated (including extensive geotechnical investigations on the Lower Dam) as part of the studies conducted earlier this year, with the finding that the risks and consequences of failure due to earthquake hazards were much lower than those due to flooding (storm) hazards (Golder 2014, b and d). Similarly, the extent of flooding and the consequences related to the earthquake and “other causes" induced failure modes were significantly lower that the above storm induced failure modes and therefore do not control dam classification.”

It is clear to me on reading the Engineer reports prepared by Golder that there was an urgent schedule set up to focus on remediation of the dams in 2012. However this context has changed as evidenced by the findings resulting from further investigative studies and analysis. However the Water Comptroller insists on treating the dams as though the conclusions arrived at by Associated Engineering were still applicable. They are not.

9. I quote the following from the Golder Remediation Options Report dated August 29, 2014:

“In-situ management of contaminated soil, or other material, would typically include an assessment of risk to human health or the environment, resulting from these materials remaining in-place. Also, given the accessibility of the Site to potential receptors (human, terrestrial, avian, aquatic, etc.), potential exposure to the identified soil contaminants is considered possible, and the risk associated with such exposure should be evaluated.
It is recommended that a preliminary risk assessment be conducted, based on existing conditions, to help make sure that no sensitive receptors have been missed, that critical pathways have been evaluated, and to verify that no unacceptable risk is incurred as a result of in-situ management. If issues are identified through such an assessment, a plan for risk mitigation may then be developed.”

Should we not be concerned that the risk of exposure to potential soil contaminants has not been properly evaluated and in an attempt to comply with the timelines ordered by the Comptroller that work may proceed without this precautionary step being completed thereby putting downstream residents at increased risk. I believe that the City needs to take the time to complete these types of analyses before any remediation work in the ground is carried out. Moreover I have concerns that the timelines will not permit completion of the required further site investigation and other assessments work as per the below excerpt from Golder’s Remediation Options Report of August 2014:

5.5 Further Work
Site investigations. The investigations to date have provided information necessary to undertake preliminary designs of remediation options for the Lower Dam. In order to complete a detailed design, further geotechnical investigation work is required which would include:
Additional drilling into the downstream face of the dam to better delineate the material (particularly the cinder and slag fill); and,
Drilling along the foundation of the proposed spillway to identify soil conditions and the depth and quality of bedrock.
Other assessments. Additional assessments such as geo-environmental assessment (as described earlier in this report) will be required as the project proceeds.

10. I have comfort and confidence with the City's current evacuation plans in the event of a flood and believe that a rainfall event of the magnitude required to cause overtopping of the dams would happen over the course of sufficient time to allow the City to take emergency measures such as pumping, sandbagging, etc. These types of short term mitigation measures will also reduce the stated risk of granting a stay and or extension of the timelines ordered by the Comptroller.

11. I believe the City has very good reason to ask for a stay or extension to carry out further diligence, especially in light of the established reduced risk to public safety. This can be supported by the following excerpts from Golder's reports as follows:

a) Remediation Report August 29, 2014:
- “Having a timely permanent solution in place by no later than 2015 and ideally in 2014.” (Note that this goal was set under the context of the Associated Engineering Inundation Report of 2012.)
- A key project challenge was the tight timeframe, as there was a strong preference to carry out the options assessment and selection as well as detailed design and construction of the dam remediation in 2014.
- Due to access, budget and time restraints, a test pit investigation program was considered optimal for collecting information on the properties of the dam fills on the downstream face, near the existing spillway and on the dam crest.
- A third planned core hole (CH14-01) was not completed due to time constraints.
- Due to time constraints, the development of the remediation options was carried out concurrently with the site investigation (Golder 2014a), the risk assessment (including the dam safety analyses, (Golder 2014 b, c and d) and the dam re-classification. This parallel sequence of events required some assumptions during the options development, including the use of the design criteria for the previous dam classification (since the dam was not re-classified until later in the options development), as well as certain assumptions of how the risk assessment may be applied (since, for DSS, this was the first application of the risk assessment process for dam safety analysis in BC).
- Due to time constraints this list of initial options was developed in conjunction with a preliminary flow and scour analysis.
- Due to poor supportability of the loose cinders and slag fill surface which might settle or move with time, construction difficulties of forming and placement of concrete on a steep surface, cost and time limitations, the CRCS option was not carried forward as an overtopping protection system.
- In order to provide a consistent basis for comparison, the screened option assessment was based on a hydraulic capacity of 175 m3/s. At the time this work was undertaken the dams were both assigned a consequence classification of Extreme, and therefore a conservative flow requirement, slightly greater than the regulatory requirement (PMF), was selected. As noted in Section 4.0, the hazard classification for the Lower Dam was later reduced to Very High.
b) Risk Assessment June 2014:
- These predictions took into account the potential effectiveness of evacuation warnings and considered “incremental” consequences (i.e., consequences that are in addition to those that would occur if the dams were not there). For several scenarios, flooding or incremental consequences have been interpolated/extrapolated from the results of other scenarios, due to the high cost and time required for hydraulic modeling.

allvoices

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