Dufferin Aggregates,
a Division of Holcim (Canada) Inc. Part II - Section I Water Budget
Part II — Section I Water Budget
Table of Contents
Page
Section 1.0 Introduction 1
Section 2.0 Monitoring 2
2.1 Monitoring Locations 2
2.2 Monitoring Frequency 2
2.3 Other Monitoring Information 2
Section 3.0 Data Evaluation 2
CONESTOGA-ROVERS & ASSOCIATES
030193 (22) AMP Part ILI
November 2014
Dufferin Aggregates,
a Division of Holcim (Canada) Inc. Part II - Section I Water Budget
Part II - Section I
Water Budget
Section 1.0 Introduction
The established water budget for the entire Acton Quarry will be evaluated on a regular basis to
ensure that sufficient water is available for ongoing and future mitigation, operational, and
rehabilitation requirements. The objectives of the water budget evaluation include:
• Verify that the amount of water available/in storage is consistent with anticipated water
budget conditions and to confirm the representativeness of the overall water budget
calculations
• Establish the annual distribution of the water from the reservoir in accordance with the
allocation priorities identified in Part I Section 2.0
• Confirm the representativeness of key water budget parameter values that have the
potential to significantly affect the reliability of the long-term water budget calculations in a
negative manner (i.e., potentially less water available than forecast)
• Identify and adapt to any long-term trends in water budget availability that are evidenced
by the monitoring data and/or recognized by the scientific community
The principal basis for assessment will be through measurement of the reservoir water level
(i.e., amount of water in storage) and the progression of rehabilitation lake filling in the
extracted phases. On an annual basis, these data will be compared to anticipated water budget
conditions to ensure the water budget is acceptable.
At key milestones (refer to Part II Section J, subsections 3.2 and 3.4), the water budget will be
reviewed and the underlying surface water and/or groundwater models will be
updated/re-calibrated as warranted to reflect the information collected to date.
More specific information on the water budget program for the AMP is described below. This
program described herein will be reported and reviewed annually to evaluate whether the
objectives of the water budget verification are being achieved and whether it is appropriate to
modify the monitoring and/or analysis program.
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Section 2.0 Monitoring
2.1 Monitoring Locations
• Water levels will be measured in the reservoir and any other quarry area holding significant volumes of water (e.g., partially flooded phases holding more than an estimated
250,000 cubic metres [m 3 ] of water)
• Water flow will be monitored from individual dewatering/transfer points and individual
discharge locations and mitigation recharge wells
2.2 Monitoring Frequency
• Reservoir water levels will be measured on a "continuous" basis using an automated water level recorder.
• Water levels will be measured in other areas holding an estimated volume of more than 250,000 m 3 of water at a minimum frequency of monthly during non-frozen conditions.
• Water flows from individual dewatering, transfer, and discharge/recharge points (local
recharge well clusters may have combined total flow readings) will be measured continuously (i.e., totalizing flow meters). Readings will be recorded at a minimum
frequency of once per month.
2.3 Other Monitoring Information
In order to determine anticipated water storage levels, an accurate topographic survey will be conducted following completion of extraction and rehabilitation earthworks in each water storage area, including the Phase 1 and Phase 2 reservoirs and the Phase 4 and Phase 3/5/6
lakes (refer to Part I Figure 3). The survey will be completed prior to the initiation of substantial lake filling, although some survey limitations may occur for the existing Phase 1 area which presently retains a large depth of water. The survey will be used to calculate a stage-storage
curve for each area. Using the available information and the water budget information
currently estimated filling times can be refined based on the measured storage volumes.
In order to facilitate water budget assessments, additional data will be collected as necessary.
Section 3.0 Data Evaluation
The measured water levels (volumes) and flows will be compared to the anticipated water budget conditions (refer to CRA memorandum of October 27, 2014, or as may be updated from
time-to-time, for supporting technical information) over time to assess the water budget and
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lake filling progression in accordance with the objectives identified above. The analysis of the
water budget will be completed in accordance with the following procedure:
1. Complete water budget analysis as described herein. This analysis occurs at different
levels of detail at different frequencies:
• Ongoing - assessment of flow and storage data relative to previous measurements,
forecasted water budget conditions, and ongoing operations and climatic conditions
• Annual - review of data relevant to individual monitoring parameters and overall
water budget
• 5-Year Review - analysis of overall water budget considerations and
representativeness of water budget calculations
2. Identification of whether actual water budget conditions are consistent with anticipated
conditions, or whether more/less water is available.
3. In the event that significantly less water is available or there is other indication that
there are other potentially significant discrepancies between the actual and forecast
water budget, further assessment of the water budget and water use, including
groundwater recharge operations, will be undertaken and appropriate response actions
implemented, if necessary. These measures may include:
• Further evaluation of monitoring data, parameter estimates, water budget
calculations, water management system operation
• Completion of micro-water budgets for sub-components of the overall water budget
• Specific field investigation/monitoring programs to collect additional information
(e.g., installation of additional monitoring wells, flow meters, lysimeters, etc.)
• Further review of the scientific literature for related water budget consideration
The timeframes for the foregoing measures will be based on the objective that the
quarry progression will be limited during this period if necessary, to ensure that the
Water Management System is sustainable based on the current water budget
parameterization.
In the unexpected event that appropriate response actions do not appear to be
available based on longer term evaluation (i.e., annual and 5-year reviews) the
appropriateness of continuing extraction over the long term will be evaluated to
determine whether a cessation of extraction activities that result in further water
budget stresses is necessary in some or all areas. Based on work completed to date,
there is ample water to protect off-Site features, and any significant reduction would be
based on future climatic conditions (in which case the features would not have the same
amount of water regardless).
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4. In the event that there is more water available than forecast, the amount of additional
water will be established and dealt with in accordance with the water allocation
priorities described in Part I Section 2.0.
As the final lake filling stage is approached, the water budget will be further reviewed and
refined to ensure that sufficient water will be available and to confirm how much excess water
will be available under the final "lakes filled" condition. This assessment will include an analysis
of any changed circumstances, including an updated analysis of the potential effects of global
climate change which may be much better defined at that time than they are at present. Such
assessments will include review and, if necessary, additional assessment of anticipated water
budget parameters associated with revegetation/rehabilitation conditions, as required to
confirm the sustainability of the rehabilitation conditions. These analyses may be used as a
basis for further refinement of the rehabilitation plan and ultimate land use plans in the event
that conditions indicate a revised plan would be of greater overall benefit to the water
resources and associated features.
CONESTOGA-ROVERS 8. ASSOCIATES
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a Division of Holcim (Canada) Inc. Part II - Section 1 Reporting
Part II — Section J Reporting
Table of Contents Page
Section 1.0 Introduction 1
Section 2.0 Regular Reporting 1
2.1 Annual AMP Monitoring Report 1
2.2 5-Year Review Report 3
2.3 On-Line Reporting 4
Section 3.0 Circumstance-Specific Reporting 5
3.1 Pre-Extraction Reports 5
3.2 Mitigation Implementation Verification 6
3.3 Agency Notifications and Mitigation Plans 7
3.4 Confirmatory Reporting Prior To Lake-Filling 8
3.5 Other Circumstances 8
CONESTOGA-ROVERS & ASSOCIATES
030193 (22) AMP Part 11.1
November 2014
Dufferin Aggregates,
a Division of Holcim (Canada) Inc. Part II - Section J Reporting
Part ll - Section .1
Reporting
Section 1.0 Introduction
The AMP includes both regular reporting and circumstance-specific reporting.
Regular reporting includes the annual monitoring report, the 5-year review reports, and the
ongoing provision of on-line data access as described in Section 2.0. The annual and 5-year
review reports will be made available to the public by Dufferin. The on-line data access will be
provided to designated agency technical representatives responsible for assessing Dufferin's
implementation of the AMP. The following sections detail the reporting associated with the
AMP.
Circumstance-specific reporting includes pre-extraction reports, mitigation verification reports,
agency notifications, and other circumstances as described in Section 3.0.
For report submission timing, refer to Part I Sections 3.0 (AMP Requirements) and 4.0 (Ongoing
Requirements).
Further information on these reporting requirements is provided below. Note: some of
information such as private water supply monitoring or complaints may be limited in respect of
privacy limitations.
Section 2.0 Regular Reporting
2.1 Annual AMP Monitoring Report
A comprehensive AMR will be prepared documenting the implementation and operation of the
mitigation measures and recommendations for future mitigation system requirements in
accordance with the AMP. The report will be submitted to the agencies by April 30 of each year
covering the previous calendar year. The first report will be due April 30 in the year following
issuance of the licence, for the previous year in which the licence was issued.
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The AMR will include the following:
• Status and summary of quarry operations (e.g., development, extraction, and
rehabilitation).
• Status and summary of mitigation system development and implementation, including any
anticipated upcoming changes in requirements.
• All monitoring data for the reporting period (Note: transducer data may be sub-sampled for
presentation in the AMR to limit size of data files), including available climate data from
regional or local stations.
• Analysis and presentation of monitoring results, including summary of any notifications
provided under the response action framework (Part ll Section F).
• Summary of response actions taken to maintain PBT levels (and effectiveness of actions).
• Explanation and assessment of potential for impacts resulting from any period or area in
which water level PBTs or water quality effluent criteria were not continuously maintained.
• Any PBT adjustments based on climate conditions (background monitoring) and
supplemental monitoring and operating experience, as appropriate
• Assessment of supplemental monitoring program findings, including ecological aspects,
following triggers identified in Part ll Section G, Table G.1. The trigger-based assessment
framework for assessing the supplemental monitoring results and to stream-line the
reporting such that reporting can be focused to potentially important aspects of the
monitoring results as identified by the triggers.
• Evaluation of overall water budget and determination of excess water and appropriate
water allocation for the subsequent year.
• Documentation of any minor variations or exceptions in the AMP implementation that were
encountered throughout the year.
• Summary of any water-related complaints received and actions taken in response (subject
to privacy considerations).
• Review appropriateness of response/notification timelines identified in Part II Section H.
• Identification of a suitable interim extraction area (if needed due to required cessation of
extraction elsewhere) and any continued/future interim extraction.
• Summary of any amendments or modifications to the monitoring, mitigation, PBTs, or AMP
implementation that were agreed to throughout the year.
• Conclusions.
• Recommendations, including any proposed amendments or modifications to th,?
monitoring, mitigation, PBTs, or AMP implementation reflecting knowledge gained from
actual operating conditions and monitoring results (e.g., re-survey locations, calibration of
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monitoring equipment, adjustment of monitoring frequency, addition or amendment of
monitoring locations, etc.).
In addition to the above aspects, the annual reporting will include an overall evaluation of the
performance of the mitigation measures to confirm that the mitigation performance objectives
are being achieved and that continued extraction and mitigation operation is sustainable over
the long term. This evaluation will consider all aspects of the operation and monitoring
activities described in the AMP. Some specific considerations that will be addressed include the
following questions:
1. Are the operating practices consistent with the mitigation performance objectives?
Specifically, are the PBTs being maintained in a manner that is protective of the water
resources? The appropriate pattern of water level variations relative to the target levels
will become more evident as operating data becomes available; however, it is the
intended performance objective that the PBTs will be maintained for the majority of the
time, without large fluctuations in water level above or below the target levels, and that
the duration of such fluctuations will be kept to a minimum. It is recognized that
climatic conditions may result in wider variations (e.g., extreme wet events) and
additional discharge of water may be necessary for provision of downstream systems
(particularly 1.6 Mile Creek) consistent with historic quarry operating practices.
2. Are the mitigation measures protective of the water-dependent ecological features?
The ecological monitoring information will be evaluated in conjunction with the other
monitoring data to identify whether ecological features are being protected. In the
event that a negative effect to ecological features appears to be evident (unless the
change is clearly not attributable to Dufferin's activities - e.g., climate, upstream
issues, etc.), further investigation and assessment will be undertaken to determine what
response actions may need to be implemented to ensure the protection of the
water-dependent ecological features.
2.2 5-Year Review Report
Once every 5 years, a reassessment of the AMP will be conducted and reported in conjunction
with the annual monitoring reports. The timing for initial and subsequent review reports is
described in Part I Section 4.0.
This assessment will consider all aspects of the AMP from a broader context than the annual
review, including:
• Monitoring programs, including monitoring locations and frequency.
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• Supplemental monitoring triggers (expected conditions based on monitoring). The
trigger-based assessment includes the framework for assessing the supplemental
monitoring results and to stream-line the reporting such that reporting can be focused to
potentially important aspects of the monitoring results as identified by the triggers.
• PBT refinements, if warranted, and identification and development of
additional/replacement PBTs, if needed.
• Ongoing monitoring and site investigation results and any updates to hydrogeology,
hydrology, or ecology characterization.
• Mitigation measures.
• Mitigation objectives in relation to effects of long-term climate variation.
• Water budget.
• AMP procedures.
• Overall evaluation of performance of the mitigation measures in achieving the primary
objectives of the system.
• Analysis and evaluation of relevant trends in monitoring data.
• Reporting.
• Conclusions.
• Recommendations, including any proposed amendments or modifications to the
monitoring, mitigation, PBTs, rehabilitation, or AMP implementation.
It is noted that wetland U3 has been assigned a PBT and a diffuse discharge; however it may be
adequately maintained without the use of diffuse discharge to this feature. Wetland U3 may be
supported adequately by its natural condition, support of underlying groundwater levels (via
recharge well operation), and seasonal overflow from wetland U4. The need and merits for a
PBT and dedicated mitigation for U3 will be assessed as part of the 5-year reviews.
The effectiveness of the planned Green Line well and supplemental monitoring for the
protection of wetland U2 will be evaluated as part of the 5-year reviews. If warranted, the
planned new supplemental monitoring well at the northwest corner of Phase 4 (between the
extraction limit and wetland U4) could be considered for use as an additional Green Line PBT
well.
2.3 On-Line Reporting
During the operation of bedrock extraction and/or mitigation measures, suitable monitoring
data will be promptly entered into an electronic database, which can be accessed on-line by the
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a Division of Holcim (Canada) Inc. Part II - Section.) Reporting
appropriate regulating agencies. The information that will be available on-line will include, at a
minimum:
• All physical monitoring data such as groundwater levels, surface water levels, flows, and
water quality. High frequency transducer data will generally be reduced (sub-sampled) to
manage data set size. Some data for off-Site locations may be subject to privacy limitations.
• Map of all associated monitoring locations.
• Applicable PBTs and historic water levels ranges.
• Summary of the current operating condition relative to those levels (e.g., green, yellow, or
red zone) and any current occurrences or incidents as described in Part II Section F.
• Electronic copies of all public and agency reports and agency notifications.
• Identification of key personnel and responsibilities as well as associated contact and site
access information.
Prior to commencing extraction below the bedrock groundwater level within Phase 4, the
on-line (i.e., internet accessible) database will be developed and made operational and
accessible to designated agency technical representatives. As identified above, data will
promptly be made available. For example, data for applicable PBT monitoring locations
(groundwater and surface water) will be entered into the on-Site operations database on a daily
basis (operating days) and uploaded to be available on-line within 24 hours (or the next
business day). The specific implementation and access details for the database will be
confirmed with the agencies prior to Phase 4 bedrock extraction.
Section 3.0 Circumstance-Specific Reporting
To ensure that the implementation is conducted in a progressive, proactive, and protective
manner with clear accountability, a series of two pre-extraction reports and two mitigation
implementation verification milestones, as well as other circumstance-specific reporting
requirements have been identified in Part I of the AMP. These requirements are described
herein.
3.1 Pre-Extraction Reports
Reports will be submitted to document the pre-extraction requirements described in Part I
Section 3. Two pre-extraction reports are required; one prior to extraction below the bedrock
groundwater level in Phase 4 and one prior to extraction below the bedrock groundwater level
in Phase 5 West/6. Phase 5 East does not require a pre-extraction report.
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The pre-extraction report will include:
• Location of selected "final" PBT and Green Line monitoring locations for the applicable area
north or south of 22nd Sideroad (refer to Part I Section 3.1.1 and Part I Section 3.2.1)
• Selection of "final" PBTs for associated monitoring locations including associated analysis
and confirmation that the PBTs are appropriate (e.g., achieve the intended outflow
conditions from wetland U7 towards wetland U8 but not unintended outflow conditions
such as discharge from wetland U5).
• Location of background monitoring locations and existing supplemental monitoring
locations
• Summary of baseline water level data, including historic ranges (e.g., monthly)
• Summary of baseline ecological monitoring data
• Current information from private well baseline survey and water supply augmentation
assessments (subject to privacy limitations)
• Summary of key information from mitigation design and implementation verification
• Water budget table update and amount of water in storage in reservoir(s)
• Appropriate recommendations, if any, to amend the AMP relative to available information
The mitigation implementation verification requirements are described separately in
Section 3.2 below.
3.2 Mitigation Implementation Verification
Further to Part I of the AMP, the identified mitigation implementation milestones and
associated requirements are described below:
Milestone 1 Phase 4 Mitigation Implementation Verification
For the groundwater recharge well system component, the verification will include
confirmation that there is connectivity between installed recharge wells (i.e., by individual
recharge well operation and monitoring) and that all associated Green Line wells (i.e., to the
north) can be influenced. For the diffuse wetland discharge components, the verification will
include confirmation that the water levels can be raised in the associated features and that
there are no unexpected interfering conditions such as downed trees or beaver dams
obstructing surface flow.
All information and data will be included in a verification report to be submitted to the agencies
for review in advance of extraction below the bedrock groundwater level in Phase 4. To the
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extent that any components of the water management system are in a temporary condition (e.g., manual operation or overland piping) a timetable for permanent operating condition and
assessment of suitability of operating with the temporary condition will be included in the verification report.
Milestone 2 Phase 5 West/6 Mitigation Implementation Verification
For the groundwater recharge well system components, the verification will include confirmation that there is connectivity between installed recharge wells (i.e., by individual recharge well operation and monitoring) and that all associated Green Line and Groundwater
PBT monitoring wells can be influenced. For the diffuse wetland discharge components, the verification will include confirmation that the wetland water levels can be raised in the
associated features and that there are no unexpected interfering conditions such as downed trees or beaver dams obstructing surface flow.
The Phase 5 West/6 mitigation implementation verification will also include an assessment of
the performance effectiveness of the Phase 4 mitigation system relative to the ability to maintain PBTs, comparison to anticipated conditions, and overall effectiveness in protection of water resources and related ecological features. This assessment will include a review of the
groundwater and surface water analyses, including an update of the underlying models if warranted based on the review.
In the event the Phase 5 West/6 mitigation implementation is not verified to operate as intended or the Phase 4 mitigation performance is not reliably achieving PBTs, extraction will not proceed below the bedrock groundwater level in Phases 5 West/6.
All information and data will be included in a verification report to be submitted to the agencies for review in advance of extraction below the bedrock groundwater level in Phase 5 West/6. To
the extent that any components of the water management system are in a temporary condition (e.g., manual operation or overland piping) a timetable for permanent operating condition and assessment of suitability of operating with the temporary condition will be included in the
verification report.
3.3 Agency Notifications and Mitigation Plans
Agency notifications required pursuant to the response action plan described in Part II Section F will be provided by email, or other means acceptable to MNRF, to the MNRF ARA Inspector and other agency representatives as typically involved at the time of notification.
Notifications will also be recorded and maintained in the on-line data access tool described in Section 2.3 above.
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In the event that a response action mitigation plan as described in Part II, Section F.2.2.3 and
Part I Figure 1 is necessary, the mitigation plan will include the following components:
• Summary of the situation resulting in the yellow/red zone condition
• Summary of the response actions implemented and results to date
• Analysis of potentially applicable alternative solutions, including a "no further action"
alternative
• Recommended alternative solution and rationale for selection, including assessment of any
risk of impacts from implementation and measures that can be implemented to prevent
re-occurrence
3.4 Confirmatory Reporting Prior To Lake-Filling
Due to the variability associated with in-field conditions and climate conditions over the
long-term, confirmatory studies will be conducted prior to the completion of rehabilitation in
accordance with Part II Section K and if necessary suitable refinements, contingency measures,
and/or monitoring can be implemented. This assessment will be submitted for agency review
and will include a review of the groundwater and surface water analyses, including an update of
the underlying models if warranted based on the review, and may coincide with analyses
described in Section 3.2 (above).
3.5 Other Circumstances
As necessary, other circumstances will be documented and reports submitted to MNRF and
other agencies.
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Part II — Section K Rehabilitation Implementation
Table of Contents
Page
Section 1.0 Introduction 1
Section 2.0 Confirmatory Reporting Prior To Lake-Filling 1
Section 3.0 Post Lake-Filling Confirmation and Monitoring 3
List of Figures
(Following Text)
Figure K.1
Figure K.2
Figure K.3
Figure K.4
Figure K.5
Rehabilitation Plan - Key Plan
Rehabilitation Water Management and Mitigation - Phase 4
Rehabilitation Water Management and Mitigation - Phase 5/6 Western Portion
Rehabilitation Water Management and Mitigation - Phase 5/6 Eastern Portion
Rehabilitation Water Management and Mitigation - Phase 5 East
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a Division of Holcim (Canada) Inc. Part ll — Section K Rehabilitation Implementation
Part ll - Section K
Rehabilitation Implementation
Section 1.0 Introduction
This section of the AMP describes the overall water management system considerations and
requirements for establishment of long-term (post lake-filling) rehabilitation conditions. The
rehabilitation plans are illustrated on Figure 3 of Part I and described in Part ll Section A.4.0 and
on the ARA Site Plans. Figures K.1 to K.5 herein present additional detail regarding the
rehabilitation water management and mitigation plans for the Site (refer also to CRA
memorandum of October 27, 2014, or as may be updated from time-to-time, for supporting
technical information).
Under long-term rehabilitation conditions lake levels will be maintained by inter-lake leakage
through the remaining rock and constructed buttresses (where present), gravity overflow
pathways (i.e., swales and culverts), limited lake-to-lake water transfers (i.e., pumping and
gravity flows) as necessary, and some continued seasonal interim mitigation system operation
(as required). Some seasonal top-up of lake levels is anticipated to optimize the beneficial use
of the available water. The lakes will tend to stabilize the natural groundwater level
fluctuations near the quarry; however the lake level variations in conjunction with the natural
seasonal fluctuations of bedrock groundwater will increase away from the lake, allowing natural
or passive ephemeral/intermittent flooding of the wetlands once the lakes are full.
Section 2.0 Confirmatory Reporting Prior To Lake-Filling
Due to the variability associated with in-field conditions and climate conditions over the
long-term, confirmatory studies will be conducted and submitted for agency review prior to the
completion of rehabilitation and, if necessary, suitable refinements or contingency measures
can be implemented. The confirmatory rehabilitation studies include confirmation of the
optimum final lake levels and seasonal variations, water budget analysis, detailed design for the
hydraulic buttresses and geotechnical engineering analysis for the quarry walls, as well as
long-term seepage assessments. The required modifications to transition the interim WMS to
the final rehabilitation WMS will also be determined. The preference for discharges will be by
gravity, however, may be pumped based on in field conditions (e.g., W2-N) and overall
optimization of ecological conditions and water benefits and minimization of long-term
engineering requirements such as active pumping and hydraulic buttress elevation (i.e., lake
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level). These requirements are described in Part I (Section 3.0), Part II Sections A and I, and on
the Site Plans in addition to the following information.
Hydraulic Buttresses
The construction of buttresses for rehabilitation along certain quarry faces is proposed. The
buttresses will create variable edge habitat characteristics and the 'hydraulic buttresses' will
also support the Phase 3/5 West/6 lake level to buffer the lake level and natural groundwater
level fluctuations, as well as limit seepage of water through the buttresses. The hydraulic
buttress will limit flow/seepage across it, but not prevent flow, therefore, rapid changes in lake
levels or groundwater levels in these areas will be buffered/slowed by the hydraulic buttress.
In areas where buttresses are proposed for hydraulic control purposes (as opposed to simply
"landscaping"), a detailed engineering design will be completed prior to construction to ensure
appropriate consideration of the available buttress materials, exposed bedrock conditions, and
hydraulic requirements. The potential areas identified are south of 22nd Sideroad. The
preliminary engineering design has been completed (CRA letter report dated May 27, 2013) and
further requirements for the hydraulic buttress engineering design are addressed under the
ARA Site Plans. Part of the final design may consider alternate designs taking into consideration
site-specific circumstances encountered and available material. Any major deviations to the
design will require an amendment to the ARA Site Plans.
Quarry Wall Seepage and Karst Analysis
Prior to commencement of lake filling in Phase 4 or Phase 3/5 West/6, the areas between
adjoining quarry cells that are not covered by a hydraulic buttress will be evaluated to ensure
that they are suitably stable (e.g., no loose rock) and that long-term seepage will not increase
to any unacceptable level over the long-term due to the process of dissolution of the bedrock.
While all carbonate rocks in contact with water are generally subject to some dissolution over
time, dolostone bedrock, including the Amabel found at this Site, has a dramatically slower rate
of dissolution than limestone. Limestone (and other more soluble minerals) is recognized to be
susceptible to appreciable dissolution over periods of centuries (or less) in some situations.
Although the rate of dolostone dissolution is known to be very slow relative to limestone, the
following program will be implemented for the areas of Phase 4 and Phase 3/5 West/6 West
noted above (i.e., exposed final rock faces). This information will also be considered in the
geotechnical analysis described above.
1. Final extraction faces will be mapped in detail (such as high resolution photography) to
identify fracture occurrence and character with particular attention to the size, extent,
and character of any open fractures. Mapping will include seepage surveys under
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winter freezing conditions and spring freshet conditions. Any significant water bearing
feature will be located by survey for future reference if necessary.
2. Hydraulic conductivity of the entire thickness of the rock mass will be tested (pressure
packer testing) at representative locations suspected of having higher permeability,
including areas of potentially significant seepage that may be noted (as above).
3. The potential for ongoing dissolution under the long-term rehabilitation conditions will
be analyzed using the then current scientific understanding and predictive techniques
available. If necessary, this may include the commissioning of particular research
focused on the dissolution kinetics of Amabel dolostone.
4. If the foregoing work concludes that significant increases in seepage may occur as a
result of long-term dissolution processes, appropriate measures will be implemented to
manage the situation. Such measures may include: consideration of potential top-up
flow requirements, extension of hydraulic buttresses to address localized or broader
areas, localized grouting of more permeable zones, long-term monitoring and
accommodations for future contingencies, or a combination of these (or other)
measures.
5. During the lake filling period, seepage surveys of downstream quarry faces and water
budget evaluations will be utilized to help identify any unanticipated levels of leakage
and, if necessary, implement measures as described above.
Section 3.0 Post Lake-Filling Confirmation and Monitoring
Upon achievement of the final rehabilitation lake levels, monitoring will be conducted to ensure
that suitable long-term conditions are achieved. Monitoring will include assessment of water
levels and flows (e.g., lake top-up flows) as well as ecological conditions. If necessary, the
proposed lake levels will be modified to better protect the surrounding ecological features. If
adjustment of lake levels is not adequate, additional measures will be considered such as
grouting, additional fill material, additional gravity drainage structures, etc., depending on
Site-specific conditions identified at that time.
The need for, and requirements of, any ongoing long-term monitoring will be identified prior to
cessation of monitoring. At present, it is anticipated that some monitoring will continue to be
necessary. At a minimum, it is anticipated that monitoring will include water levels in the
reservoirs and possibly lakes, as well as flows for pumped discharges and perhaps gravity
overflows.
The confirmatory analysis will be submitted for agency review as described in Part I,
Section 3.1.3 and 3.2.3.
CONESTOGA-ROVERS & ASSOCIATES
030193 (22) AMP Part II .K
November 2014
3
GLEN • 125 250 37501
BLACK C
1; 7:64,'Ij s•:\
• • PLANT \ YARD Low.
UPPER SETTLING POND \
•
• • • •
• \ • • • ‘‘
• \ PHASE 1
RESERVOIR MAX 341 m AMSL
---------------
------------
-------- - - - - -
--
W2-S
----------
PHASE 5 WEST/ 6 WEST
------ —
PHASE u6 5 EAST
5 --- 2•1'
"9-N)
HYDRAULIC —"*" BUTTRESS TO 2357 m AMSL
-U27
NOTES: 1. ACTUAL ALIGNMENT OF WATERMAINS/DISCHARGES MAY VARY. 2. REFER TO ARA SITE PLANS FOR EXTENTS OF REHABILITATION
LAKES AND RESERVOIRS WITHIN EXTRACTION LIMITS. 3. REFER TO PART II SECTION K.1.0.
LOCAL DISCHARGERNTERCONNECTION OF WATER (GRAVITY FLOW) SITE DISCHARGE OF WATER (GRAVITY FLOW) GRAVITY WATERMAIN/CHANNEL FLOW PUMPED FLOW PROPOSED QUARRY DISCHARGE/MITIGATION (PUMPED)
SOURCE BASE MAPPING OBTAINED FROM NORTHWAY PHOTOMAP cos INC , DERIVED FROM NOVEMBER 22.2011 AERIAL PHOTOGRAPHY 0 QUEENS PRINTER FOR ONTARIO PRINTED IN ONTARIO, CANADA OCTOBER 2011 figure K.1
REHABILITATION PLAN KEY PLAN
ACTON QUARRY EXTENSION Town of Halton Hills, OnZwio
30193-10(022)GN-WA005 NOV 2112014
MOVEMENT OF WATER
LOCAL DISCHARGE/INTERCONNECTION OF WATER (GRAVITY FLOW) SITE DISCHARGE OF WATER (GRAVITY FLOW) GRAVITY WATERMAIN/CHANNEL FLOW PUMPED FLOW
NOTE ACTUAL ALIGNMENT OF WATERMAINS/DISCHARGES MAY VARY.
711°. WMS CONTROL HUT 111111111119/11111)J11-111111)1)A1,,IIIIII VV1111111I figure K.2 REHABILITATION WATER MANAGEMENT AND MITIGATION
PHASE 4 ACTON QUARRY EXTENSION
Town of Halton Hills, Ontario
SOURCE. BASE MAPPING OBTAINED FROM NORTHWAY PHOTOMAP INC.. DERIVED FROM NOVEMBER 22. 2001 AERAL PHOTOGRAPHY CONTOUR INTERVAL RI METRE
SWOOP 2010 0 2011 OF THE QUEENS PRETTER FOR ONTARIO. ALL ROOTS RESERVED.
30193-10(022)GN-WA017 OCT 3112014
?ILIA: . -,77Arvilr. i .i., fd-ffler
1
77,e e
LAKE AVG -355 m Alan
RAN
ol•
11. •
-g■ figure K.3
MOVEMENT OF WATER
LOCAL DISCHARGE/INTERCONNECTION OF WATER (GRAVITY FLOW) SITE DISCHARGE OF WATER (GRAVITY FLOW) GRAVITY WATERMAIN/CHANNEL FLOW
NOTE: ACTUAL ALIGNMENT OF WATERMAINS/DISCHARGES MAY VARY. PUMPED FLOW PROPOSED QUARRY DISCHARGE/MITIGATION (PUMPED) WMS CONTROL HUT
SOURCE. BASE MAPPING OBTAINED FROM NORTHWAY PHOTOMAP INC. DERIVED FROM NOVEMBER 22, 2001 AERIAL PHOTOGRAPHY
NNIIILI.122 PIEEITEE
REHABILITATION WATER MANAGEMENT AND MITIGATION PHASE 5/6 WEST - WESTERN PORTION
ACTON QUARRY EXTENSION SWOOP 2010 0 2011 OF THE QUEEN'S POKIER FOR ONTARIO ALL RIGHTS RESERVED Town of Halton Hills, Ontario
LAKE AVG -355 m AMSL
••"*-.
2357 rn AMSL
I HYDRAULIC Whilit4
BUTTRESS TO
MOVEMENT OF WATER
LOCAL DISCHARGE/INTERCONNECTION OF WATER (GRAVITY FLOW) SITE DISCHARGE OF WATER (GRAVITY FLOW) GRAVITY WATERMAIN/CHANNEL FLOW NOTE: ACTUAL ALIGNMENT OF WATERMAINS/DISCHARGES MAY VARY PUMPED FLOW WMS CONTROL HUT
SWOOP 2010 0 2011 OF THE QUEEN'S PRINTER FOR ONTARIO ALL
RIGHTS RESERVED
figure K.4
REHABILITATION WATER MANAGEMENT AND MITIGATION PHASE 5/6 WEST - EASTERN PORTION
ACTON QUARRY EXTENSION Town of Halton Hills, Ontanb
SOURCE BASE MAPPING OBTAINED FROM NORTHWAY PHOTOMAP
INC DERIVED FROM NOVEMBER 22, 2001 AERIAL PHOTOGRAPHY
CONTOUR INTERVAL DI METRE
30193-10(022)GN-WA017 OCT 3112014
RESERVOIR MAX 338 rn AMSI
-01■
MOVEMENT OF WATER
LOCAL DISCHARGEANTERCONNECTION OF WATER (GRAVITY FLOW) SITE DISCHARGE OF WATER (GRAVITY FLOW) GRAVITY WATERMAIN/CHANNEL FLOW PUMPED FLOW
NOTE: ACTUAL ALIGNMENT OF WATERMAINS/DISCHARGES MAY VARY.
SOURCE BASE MAPPING OBTAINED FROM NORTHWAY PHOTOMAP INC DERIVED FROM NOVEMBER 22, 2001 AERIAL PHOTOGRAPHY CONTOUR INTERVAL IS 1 METRE
SWOOP 2010 0 2011 OF THE QUEEN'S PRNIER FOR ONTARIO. ALL RIGHTS RESERVED
figure K.5
REHABILITATION WATER MANAGEMENT AND MITIGATION PHASE 5 EAST
ACTON QUARRY EXTENSION Town of Halton Hills, Ontario
30193-10(022)GN-WA017 OCT 31/2014