Technical Review of the Telkwa Coal Mine Proposal
This review was conducted by Dr. Patrick Littlejohn, P.Eng., Senior Chemical/Metallurgical Engineer with Source and a Qualified Professional in BC in the area of mine water treatment and discharge planning. It provides a third party technical review of the Tenas Coal Project Environmental Assessment Certificate Application and was conducted to support the Northwest Institute during the public comment period for the Application. Download the report here.
This review was conducted with the following focus areas and questions in mind:
- Geochemical sampling program – are the mineral samples collected representative of coal ore, ore halo & waste rock? Was the geochemical testing program rigorous? How much selenium is present in project rock?
- Source control – does the Project apply appropriate Acid Rock Drainage (ARD) mitigation measures in ways that make sense and align with overall mine plan and water balance (i.e. Potentially Acid Generating (PAG) rock submergence, waste rock pile design)? What is the potential for selenium release?
- Site water balance – is site water management infrastructure robust and capable of handling a wide range of weather conditions (i.e. wet years, dry years, extreme weather events)?
- Mine contact water quality – how contaminated is mine contact water expected to be and are predictions reasonable? How sensitive are predictions to things that may be uncertain, like PAG characterization, site water balance?
- Water treatment approach and capacity – how is water treatment applied, and are water treatment goals achievable with the technologies describe? Is water treatment capacity sufficient? Will treatment address potential selenium contamination?
- Discharge location – does the project design follow BC best available technology/initial dilution zone policy?
Summary of Findings
Significant risks were identified with the Application in each of these subject areas. To summarize:
- The geochemical sampling program is not sufficiently robust to characterize the ML/ARD potential of the disturbed material. The proposed approach to MLARD management relies entirely on source control, which leaves no room for error in materials identification and handling. Significant risk of onset of acid rock drainage, neutral metal leaching and selenium contamination exists with the proposed project.
- The Application contains insufficient evidence/analysis supporting the idea that the implementation of source control is practical and can be executed under a range of climate conditions or in the context of geochemical uncertainty.
- The Application includes water management features that are designed to meet 1-in-10 year storm events. Discussion of variable climate conditions (i.e. climate change) are limited. Given that the project is to operate for over 20 years with a total lifespan including closure/post-closure of close to 50 years, use of shorter or less conservative design basis adds risk of impacts to the environment.
- Expectations of mine water quality are optimistic and do not entertain the possibility of onset of ARD if any aspect of the mine plan does not go according to plan (i.e. mishandling of PAG material, failure of source control measures, higher than expected geochemical source terms, or flushing of oxidation products prior to material submergence).
- Water treatment is not included in the application. Any contamination that occurs in mine contact water is proposed to be released directly to the receiving environment without treatment. This is a significant deviation from best practices in BC and represents a major risk to the downstream environment.
- The Application proposes site specific water quality targets that are significantly less conservative than BC’s generic guidelines using a process that does not align with BC’s policy. The Application does not include use of Best Available Technology to prevent contamination and so does not follow BC policy on initial dilution zones.
Overall, the project design is predicated on an optimistic interpretation of limited geochemical data and the ability to execute a mine waste and water management strategy with little margin for error. Modeling conducted by the proponent indicates that they expect the immediate receiving environment to be degraded with mine-borne contaminants including a 200 fold increase in selenium concentration in local creeks. The project does not follow BC policy on application of Best Available Technology to prevent contamination in the downstream environment. All of these factors mean that there is significant risk of the project having both short and long term negative impacts on water quality in the downstream environment.
Cost Benefit Analysis of the Telkwa Coal Mine Proposal
On behalf of the Northwest Institute, Swift Creek Consulting has prepared an assessment of the Telkwa Coal Mine's net economic benefits and comment on the Project’s public interest case. Economic benefits play an out-sized role in public interest evaluations, and therefore it is crucial to closely examine economic net benefits so that the BC government is properly informed. Download the report here.
Critical Review of the Telkwa Coal Mine Socio-Economic Assessment
This report provides a critical review of the socio-economic components of the environmental impact assessment prepared for the proposed Tenas (Telkwa) coal project, which would be located seven kilometres southwest of Telkwa. It includes an analysis of project need and benefits, and economic, demographic, infrastructure and methodological issues.
Telkwa Coal Mine Plan - Key Issues Related to Water
Telkwa Coal Mine Plan – Key Issues
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By Patrick Littlejohn, PhD, P.Eng for the Northwest Institute June 21, 2022
These comments are based on a preliminary review of the Telkwa Coal Mine application by Patrick Littlejohn, PhD, P.Eng., a mining professional with more than ten years of experience in mine water treatment and management in BC. He will conduct a more fulsome review and contribute written comments to the Northwest Institute as part of the Environmental Assessment process.
1. Lack of appropriate water treatment: The project proposes very limited water treatment to remove suspended solids (i.e. dirt/sand particulate) and does not propose treatment of any dissolved solids in water. This does not align with BC policy on use of Best Available Technology and use of Initial Dilution Zones. Basically this policy says that if a mine expects to have contaminated water, the mine owner needs to use Best Available Technology to treat it before considering potential impacts to the environment. There is reasonable potential for water contamination from selenium and acid rock drainage. These are fairly common issues in the mining sector and there is lots of precedent in BC and elsewhere for treatment of mine water for these kinds of contamination. The project discusses active water treatment as a contingency measure but this should be part of Plan A.
2. Relaxation of water quality standards: BC has generic water quality guidelines to protect the environment. The project proposes to use relaxed water quality standards for selenium that are 4 to 17 times higher than BC’s standard guidance. Project specific water quality guidelines can be developed if there is a firm scientific basis for why the generic standard is inappropriate for a specific site and BC has detailed policy guidance on this process. Based on my preliminary review, the Tenas project does not appear to follow the policy for development of a Science Based Environmental Benchmark and so their basis for relaxing water quality guidelines for the project is questionable.
3. Optimistic design: Overall, the mine plan proposal paints an optimistic picture in terms of managing water and preventing contamination. Even the best mine plan can have problems – maybe there is more or less rain than anticipated, maybe economic conditions change and the mine goes on temporary closure, maybe source control doesn’t work well enough to prevent contamination, maybe there is more contamination released from rock than anticipated. The project application describes a mine plan that could work if everything goes perfectly. However, mines never go exactly as planned and so best practice is to have robust designs that incorporate redundancy to mitigate risks and prevent impacts.
In short:
• The mine plan does not follow BC policy with respect to water treatment.
• The mine plan proposes to use BC water quality standards that are significantly higher than BC’s generic limits.
• The project design does not seem robust enough to proactively manage risk to the environment.
Telkwa Coal
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