221 Woolwich Street AND 1 First Canadian Place, Suite 5300

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1 October 28, 2008 Garrod Pickfield LLP Davis & Company 221 Woolwich Street AND 1 First Canadian Place, Suite 5300 Guelph, Ontario 100 King Street West N1H 3V4 Toronto, Ontario M5X 1E2 Attention: Mr. Stephen Garrod & Mr. Chris Barnett Dear Sirs: Re: Proposed Rockfort Quarry Licence Application Peer Review Preliminary Comments on Consultant Addendum Submissions August 2008 Water Resources Aspects File Further to your request, we are providing our preliminary peer review comments, related to water resources aspects, of the addendum technical submissions provided in August 2008 by consultants on behalf of James Dick Construction Limited (JDCL) with respect to their application for a Class A Category 2 Licence for their Rockfort Quarry property. The subject property is located in the Town Of Caledon, Region of Peel. Our current peer review is a continuation of the peer review process that was started in 1998 for the licence application, and was suspended in 2003/2004 while the Comprehensive Broader Scale Environmental Study (CBSES) of Resource Area 9A was developed and subsequently completed by JDCL. The final report for the CBSES was submitted to the Town Of Caledon at the end of March Staff from Credit Valley Conservation provided technical input to the development of the Terms Of Reference for the CBSES, and also provided comments on drafts of the report. The CBSES deals with broader-scale issues related to the physical setting and natural environment within Resource Area 9A. The CBSES also addresses potential impacts 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

2 Page 2 Garrod Pickfield LLP & Davis & Company October 28, 2008 associated with extraction of the entire rock resource within Resource Area 9A, and discusses possible mitigation measures to manage those impacts. The CBSES does not address sitespecific issues related to the proposed extraction at the Rockfort Quarry, and, as such, we have not undertaken a technical review of the CBSES final report. The addendum documentation related to the Rockfort application that was submitted by the proponent in August 2008, which we have reviewed, is as follows: A. Water Resources Evaluation And Design Addendum Rockfort Quarry, Town Of Caledon, Ontario. Prepared by Conestoga Rovers Associates, July 2008; Reference No (11). B. Updated Adaptive Management Plan Water Resources Protection Rockfort Quarry, Town Of Caledon, Ontario. Prepared by Conestoga Rovers Associates, Ecoplans Limited and Goodban Ecological Consulting, July 2008; Reference No (8). The Water Resources And Design Addendum report provides the results of additional data collection and site characterization information that has been obtained since the submission of the technical support reports in As well, this addendum report describes modifications to the proposed mitigation measures and monitoring for the quarry operation, as well as providing additional technical support for the proposed mining and mitigation operations. The Updated Adaptive Management Plan Water Resources Protection report provides details of the proposed operational water management, and mitigation monitoring programs that are intended to protect the existing water resources and natural environment around the periphery of the quarry and within any potential zone of influence of the quarry operations. It is stated that this report updates and supersedes the August 2000 Adaptive Management Plan document. Although not stated as such, we have assumed that this Updated Report also supersedes the April 2003 Modifications To The adaptive Management Plan document that was submitted by the applicant. REVIEW CONTEXT To place our review into an overall context with respect to the short-term and long-term protection of ground water and surface water resources, and the associated natural environment features and functions, the following summary is provided. The summary applies to both the active extraction operation and the post-rehabilitation final lake conditions. 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

3 Page 3 Garrod Pickfield LLP & Davis & Company October 28, 2008 UNMITIGATED EXTRACTION OPERATION = SIGNIFICANT ENVIRONMENTAL IMPACTS The predicted scope and extent of the impacts associated with an unmitigated extraction operation is not discussed in any of the reports; we do not know if this base-case has been modeled by the proponent. It is our contention that it is important for the review agencies to know the magnitude of the predicted impacts for the unmitigated operation, as a base-case, so that the importance of the mitigation measures functioning as designed can be fully appreciated. Impacts would be expected to occur to the following: Local residential and/or farm water supplies (wells, springs etc.). Some supplies may be lost while other supplies may not be as productive. Local surface water courses and local springs may be affected by reduced flows and/or reduced groundwater inputs. Local fish habitat may be affected, possibly resulting in a Harmful Alteration Disruption Destruction (HADD) of fish habitat which would then involve the Department of Fisheries and Oceans under the Federal Fisheries Act. Local wetlands, ponds, vernal pooling amphibian habitat and other natural environmental features and functions may be affected as a result of reduced groundwater levels, surface water flows and shorter hydro-periods. FULLY MITIGATED EXTRACTION OPERATION = MINIMAL/ACCEPTABLE LEVEL OF ENVIRONMENTAL IMPACTS The initial design of the mitigation measures is based on computer modeling of the groundwater system and is premised on the maintenance of quasi pre-quarry groundwater levels in the bedrock aquifer around the extraction area. Full mitigation will require: An effective grout barrier wall around the entire extraction area to reduce/manage groundwater discharge into the quarry extraction area. An effective groundwater recharge system around most of the extraction area to maintain groundwater levels in the adjacent bedrock. A water storage system that is sufficient to supply the groundwater recharge system on a year-round basis. An effective groundwater/surface water/natural environment monitoring program and Adaptive Management Plan that is sensitive enough to detect changes upgradient of, and/or at, the receptors to provide sufficient early warning of potential impact to allow timely implementation of mitigation measures. 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

4 Page 4 Garrod Pickfield LLP & Davis & Company October 28, 2008 Final lake levels following rehabilitation that will maintain the groundwater levels and surface water flows that protect the features and functions of the downgradient natural environment receptors. INTERMEDIATE LEVEL OF MITIGATION = SOME DEGREE OF ENVIRONMENTAL IMPACT, BUT MAGNITUDE NOT KNOWN An intermediate level of mitigation would result in some degree of environmental impact to the features noted above, as a result of: Not fully-effective grout wall. Not fully effective groundwater recharge system. Insufficient water storage system. Insensitive monitoring program that does not detect change soon enough and/or does not monitor at the right locations to prevent environmental impact occurring. Final lake levels which are not high enough to protect the downgradient natural environment receptors. Therefore, in order to prevent unacceptable environmental impact from occurring, we need to understand the sensitivity of the groundwater/surface water/natural environment systems with respect to change, and the sensitivity of the mitigation measures with respect to their level of effectiveness and resulting potential change in the downstream receptors. As well, there needs to be confidence that the rehabilitation lakes will fill to a level that will be sufficient to maintain local groundwater levels and surface water flows that will protect the downgradient natural environment receptors. REVIEW COMMENTS Based on our review of the documentation to-date, we provide the following comments. 1. The design of the proposed quarry operation and the associated mitigation measures, and the technical documentation supporting that design/mitigation remains, in large part, as described in the suite of reports submitted by the proponent in August The proponent intends to rely on that original documentation in addition to the 2008 reports, as listed in Section 1.0 Introduction, page 1 Updated Adaptive Management Plan Water Resources Protection. 2. The work completed by the proponent for the CBSES was carried out at a broad scale of study (similar to a sub-watershed level of detail), and does not address site-specific issues that have been raised with respect to the proposed design/operation/mitigation of the 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

5 Page 5 Garrod Pickfield LLP & Davis & Company October 28, 2008 Rockfort Quarry. In particular, there has not been a comparison between the results of computer modeling that was undertaken for the CBSES and the modeling that was completed in 2000 for the Rockfort application. The recent documentation for the Rockfort application does not provide any commentary with respect to how closely the results of the two models correlate. It is our understanding that no new modeling has been undertaken for the Rockfort application, and that the proponent intends to rely on the work that was reported in We understand that the CBSES modeling included similar mitigation measures to that of the Rockfort modeling (i.e. a grout curtain wall and groundwater recharge wells). The site-specific Rockfort grout curtain was assigned a hydraulic conductivity value of 2 x 10-4 cm/s around the entire perimeter of the extraction area. The CBSES model included sections of the grout curtain that required a lower hydraulic conductivity value in the order of 1 x 10-5 cm/s. The proponent should explain this difference between the two models, and whether the lower value is feasible to achieve for a quarry operation. 3. The Updated/Addendum reports that were submitted in August 2008 do not include any substantive departures from the original interpretation of the physical setting of the subject area or the water resources and natural environment resources present in the area. Some relatively minor modifications have been incorporated into the design, operation and mitigation measures for the quarry, and additional technical support is provided with respect to the mining/grouting plan. It is stated in the Updated Adaptive Management Plan (Section 1.0, page 1), that the original Plan was modified to incorporate advice provided in 2003 by the Department of Fisheries and Oceans and their hydrogeological consultant Blackport Hydrogeology Inc. That advice pertains to the protection and monitoring of water resources and associated fish habitat that are present in the vicinity of the Rockfort property. 4. Jagger Hims Limited undertook technical review of the water resources reports that were submitted by the proponent in August and October We submitted preliminary review comments in June 2001, in our June 18 letter to Turkstra Mazza Associates (copy attached). We submitted detailed review comments and questions for clarification in our letter addressed to Turkstra Mazza Associates, dated October 16, 2001 (copy attached). We understand that our review comments were submitted to the proponent for response by their consultants. Jagger Hims Limited has not received a response to those review comments/questions. Therefore, as the proponent intends to continue to rely on the 2000 suite of reports, our 2001 comments/questions remain outstanding and require a response from the proponent. 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

6 Page 6 Garrod Pickfield LLP & Davis & Company October 28, The groundwater modeling component is an integral part of the Water Resources Evaluation and Quarry Design reports that were submitted by the proponent in August/October A detailed review of that modeling component was not undertaken by Jagger Hims Limited at that time pending a response from the proponent to our October 16, 2001 review comments. Since a response to our review comments has not been received to date, we have not undertaken a detailed review of the modeling component. Given the tight schedule for review of the recent technical reports provided by the proponent and submission of our review comments to the Region, we are not in a position to complete a detailed evaluation of the modeling component prior to submission of our review comments. We are not aware that a detailed review of the modeling component has been completed by CVC staff or their hydrogeology consultant Blackport Hydrogeology Inc. The modeling component should be reviewed prior to the start of the OMB Hearing. 6. Jagger Hims Limited submitted detailed review comments on the proposed Adaptive Management Plan (AMP) to Garrod Pickfield and Davis & Company, in our letter dated August 28, At that time, we provided review comments on the original AMP document dated August 2000 and on the April 2003 Modifications To Adaptive Management Plan document. A copy is attached here. Given that the proponent proposes to rely upon the Updated 2008 AMP report, some of those original comments may have been addressed in the Updated AMP document, and others may remain outstanding. 7. Jagger Hims Limited submitted a Summary Statement letter to Garrod Pickfield and Davis & Company, dated September 16, 2003, prior to the review process being suspended while the CBSES work was undertaken. The content of that letter continues to apply, pending receipt of a response from the proponent with respect to our 2001 and 2003 review comments noted above. A copy of our September Summary Statement letter is attached. 8. The following general comments are provided with respect to the document entitled: Updated Adaptive Management Plan Water Resources Protection Rockfort Quarry, Town Of Caledon, Ontario, prepared by Conestoga-Rovers & Associates, Ecoplans Limited and Goodban Ecological Consulting, dated July 2008 Reference No (8). a. As stated in Section 1.0 Introduction, page 1 of the AMP document, in principal we agree with the following general statement: The AMP is a well-established method of managing natural systems where there is inherent variability in the conditions that will be encountered (e.g. bedrock permeability). The AMP method is based on a system of design, implementation, performance monitoring, evaluation, and optimization to ensure that the mitigation objectives are achieved. Jagger Hims 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

7 Page 7 Garrod Pickfield LLP & Davis & Company October 28, 2008 Limited has been associated with the development of AMPs or variations thereof for other pit/quarry applications, and we support their use. b. When structured and implemented appropriately, AMPs are an effective science-based instrument to monitor the real-time progression of impacts on-site related to a specific type or types of land use, while providing sufficient lead time to implement predetermined mitigation measures that are designed to ensure protection of off-site groundwater, surface water and other natural environment features and functions. Measured impacts are compared to predicted impacts, so that initial predictive models can be refined and adjustments made to existing and/or proposed mitigation measures if necessary to protect the off-site environment. c. In our August 2003 review of the Adaptive Management Plan documents (August 2000, and April 2003 Modifications), we stated the following: As a general comment, we consider that the basic philosophy of the AMP approach is sound provided that: (a) You understand the physical system that you are monitoring, including the groundwater/surface water/ecology interactions at off-site locations. (b) The initial impact predictions are reasonable. (c) The design mitigation measures are implemented at the outset. (d) The monitoring program monitors the correct parameters in the right locations at the right times of the year to identify and quantify any changes that occur. Such changes have to be evaluated in terms of being acceptable or unacceptable. (e) In the event that unacceptable changes do occur, the additional mitigation measures are successful in returning the physical conditions to acceptable levels. When implemented correctly, this type of approach is reasonable and supportable. If, however, this approach is done incorrectly, then unacceptable change can occur and remain un-noticed to the point where permanent and significant (unacceptable) impact may occur. We have stated previously that, in our opinion, given the scope of the proposed quarry operation and the sensitivity of the area, the proponent should provide a practical demonstration that recharge wells located along the property boundary can develop a positive hydraulic connection that will protect and maintain the groundwater regime at: (i) groundwater discharge zones at specific off-site fishery habitat areas, and (ii) local residential wells. A program to investigate and characterize the groundwater flow conditions at key off-site fishery habitat areas south of the property is proposed 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

8 Page 8 Garrod Pickfield LLP & Davis & Company October 28, 2008 by the applicant following approval of the quarry, before any extraction takes place. It is our opinion that such work, together with a practical demonstration of the effectiveness of recharge wells along the property boundary, should be undertaken before the application is heard by the OMB. The type of factual information noted above would provide strong support that the mitigation system recharge well concept can provide the type of protection to the offsite groundwater and surface water resources that will be required at this site. We continue to hold this position. d. The general scope of the proposed Updated AMP performance monitoring program appears reasonable as a starting point for discussion with the regulatory/review agencies to achieve the stated objectives. However, since further proof of concept for the grout wall and groundwater recharge system (beyond that provided in the 2000 suite of reports and the 2008 Addendum reports), which are to be the main mitigation measures to limit off-site impacts of the quarry, has not been provided, the options are to refuse approval until such proof is provided, or to stage or phase approval in tandem with proof of concept. This type of phased Stop-Go approval would ensure that the mitigation measures are shown to be operational and effective for each subsequent phase of the extraction prior to the need for the mitigation being realized. A phased financial assurance package commensurate with the degree of risk/cost of failure tied to the Stop-Go milestones would also need to be developed to ensure that all necessary mitigation measures would be implemented as required. e. Section 2 of the AMP describes the configuration and progression of mining and mitigation measures that are being proposed. As we understand the proposal, Phase 1 is to be extracted sub-aqueously in a single lift that is 25 m deep down to elevation 357 m above sea level (masl). The extraction area is to be allowed to fill with water as extraction is occurring, to create the North Reservoir, and, as such, off-site impacts are predicted to be minimal, and mitigation should not be required. During extraction of Phase 1, which is expected to last approximately 3 years, the detailed design for the section of the groundwater recharge system required for Phase 2 will be completed and construction of that system initiated. By the end of Phase 1, the groundwater recharge system will be complete and demonstrated to be effective as required for Phase 2 initiation (page 12). Details should be provided by the proponent with respect to the extent of the recharge system that will be required for initiation of Phase 2. Section 2.2 Phase 2-Plant Area, page 13, indicates that prior to extraction in Phase 2, the groundwater recharge system for 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

9 Page 9 Garrod Pickfield LLP & Davis & Company October 28, 2008 Phase 2, including construction and testing will be completed as well as confirmation that the minimum water storage is available in the North Reservoir. This could be a suitable Stop-Go milestone event if there is a phased approval. Agency sign-off with respect to operation/effectiveness of the groundwater recharge system would be required prior to approval being given to proceed with any extraction in Phase 2. The proposed testing methodology to demonstrate that individual groundwater recharge wells will be effective along a particular section of the recharge system is discussed in the footnote on page 12: The recharge demonstration testing will include injecting water into each recharge well and observing the water level/pressure response in the adjacent recharge wells. If there is a measurable response in the recharge wells immediately adjacent to either side of the well being tested, then the demonstration is complete for that recharge well (i.e. the system has successfully provided water to the flow pathways that intersect the recharge well alignment between the wells, and thus the downgradient features will be maintained. Monitoring and evaluation of the demonstration testing will also include the nested monitoring wells, the off-site feature wells (i.e. locations ii, iii and iv as shown on Figure 4.1 and described in Section ), and other monitoring wells that exist in the potential zone of influence of the recharge well(s) being tested. The specifics of such well testing and verification monitoring should be provided by the proponent that will ensure that an appropriate measurable and sustainable hydraulic response is achieved throughout the saturated thickness of the Amabel aquifer adjacent to the recharge well being tested (i.e. not just a small water table response). As well, the testing should confirm that an appropriate hydraulic connection/response can be obtained and sustained in the aquifer at selected key locations downgradient from the recharge wells in order to ensure adequate protection of surface flow conditions and associated fish habitat. f. The proponent anticipates that extraction of Phase 2 (the Plant Area) down to elevation 370 masl can be completed without the need for any additional mitigation measures over and above the groundwater recharge wells that will be in place prior to the start of extraction in Phase 2. Should additional recharge wells be required (presumably, based on the monitoring results), they would be installed and operated as needed. The design does not call for a grout curtain wall in order to extract Phase 2. The timing of the design/construction of the grout wall that is required for Phase 3 is unclear, as noted below. 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

10 Page 10 Garrod Pickfield LLP & Davis & Company October 28, 2008 Page 13: Phase 2: During Extraction Period Complete design of grout curtain as required for Phase 3. Initiate grout curtain installation along recharge perimeter if required based on design. It is not clear as to whether installation of the grout curtain wall will be initiated during Phase 2, or whether some form of evaluation will be undertaken to determine if the grout wall will be necessary, and if it is deemed to be necessary, then construction will be initiated. This should be clarified and support rationale provided by the proponent. Page 14: Phase 2: Anticipated Status at End of Extraction Period Grout curtain wall design complete as required for Phase 3 initiation. There is no mention here of any actual construction of the grout curtain wall prior to any extraction in Phase 3. Page 15: Phase 3: Pre-Extraction: There is no mention of any construction of the grout curtain wall in this section. There is mention of a verification study prior to extraction to ensure that thermal effects of the groundwater recharge system will not result in an unacceptable change in temperature in the groundwater adjacent to cold water fish habitat located to the south of the site. Page 15: Phase 3: During Extraction Period Initiate construction of grout curtain in accordance with grout curtain design. The current anticipated grout curtain alignment for completion of Phase 3 extraction is shown on Figure 2.5. At a minimum, the portion of the alignment adjacent to Phase 3 will have a grout curtain installed to limit recirculation. Further grout curtain development (i.e. tightening of horizontal extension of the curtain alignment) will be completed as required to limit recirculation of recharge water and minimize drawdown to the east (as feasible). The proponent should indicate what action would be taken in the event that it is not feasible to minimize drawdown to the east. Page 16: Phase 3: Anticipated Status at End of Extraction Period Grout curtain system complete as required for Phase 4 initiation. Based on the foregoing, the remaining Stop-Go milestone events could be: at the end of Phase 2 and prior to any extraction in Phase 3, provided that the grout curtain wall for Phase 3 is in place and is shown to be effective; at the end of Phase 3 and prior to any extraction in Phase 4, provided that the grout curtain wall for Phase 3 has been confirmed to be effective under all extraction conditions and the grout curtain wall for Phase 4 is in place, and at the end Phase 4A, and prior to any extraction of Phase 4B, provided that the grout curtain wall around the entire perimeter is shown to be effective and the South Reservoir is in place and full of water. 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

11 Page 11 Garrod Pickfield LLP & Davis & Company October 28, 2008 Each new phase will require additional and/or expansion of mitigation measures and, as such, would pose a progressively larger potential risk with respect to the overall protection of the natural environment. Therefore, in tandem with the Stop-Go milestone events, the regulatory agencies may wish to consider a commensurate increase in the financial assurances that should be provided to ensure that the mitigation measures could continue to be operated for the necessary period of time in the event that JDCL could no longer operate the quarry. g. There may be additional points that will be raised with respect to the Updated AMP document, pending a response from the proponent to previous peer review comments dating back to The following relate to the document entitled Rockfort Quarry Project Report on Mitigation Demonstration prepared by Douglas M Heenan, P.Eng., Advanced Construction Techniques Ltd., dated July 18, a) The water testing data and the grout-take demonstration data for the various lines of grout holes indicate that there are reasonably well-defined horizons or stratifications within the vertical profile of the Amabel/Renales rock mass that have differing hydraulic characteristics. Based on a preliminary assessment of the data, the following horizons appear to be present: An upper zone from ground surface down to 7 to 10 m below grade that exhibits lugeon values in the order of 100 to 300. A middle zone that extends down to about 25 to 28 m below grade that exhibits lugeon values less than 100, and typically in the 10 to 30 lugeon range. A lower zone that is present between approximately 25 to 38 m below grade that exhibits lugeon values in the range of 160 to 375. A deeper zone that extends to the bottom of the Reynales Formation that exhibits low lugeon values in the order of 15. There is a correlation between the lugeon value and the hydraulic conductivity of the rock. This apparent stratification within the Amabel does not seem to support the proponent s interpretation of the aquifer as a single hydrostratigraphic unit, the vertical profile of which can be characterized by a single hydraulic conductivity value, as was used in the modeling. The proponent should indicate the significance of such stratification and the associated variation in the hydraulic conductivity. How would the incorporation of such stratification into the groundwater model affect the results of the model? 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

12 Page 12 Garrod Pickfield LLP & Davis & Company October 28, In the normal process for this type of study, the CBSES work would be undertaken first, and the hydrogeological conceptual model would be developed and broad-scale modeling would be done. Since site-specific detail normally would not be available, we understand that the Rockfort detail was not incorporated into the CBSES work or groundwater model. The CBSES model characterizes the Amabel as a two layer aquifer, with an upper, more fractured/weathered higher k zone that is underlain by lower k material, which was considered to be a "conventional" interpretation for the Amabel, because fracturing generally is thought to decrease/become tighter with depth. Generally, at the sitespecific level of detail, the hydrogeology at a particular property is seen to be morecomplicated, rather than less-complicated than is used at the broad scale of assessment, and the site-specific model would reflect this. So, for Rockfort, the model would be at least a two layer system for the Amabel, and possibly more layers, with differing k values. Based on the grout demonstration testing, a three layer characterization of the Amabel could be supported, with a higher k zone at depth. Since the proponent still contends that the Amabel aquifer at this location is bestcharacterized as a single unconfined aquifer unit that can be characterized by a single k value in vertical profile, with some lateral variation, then strong supporting evidence for this more-simplistic interpretation should be provided. The grouting demonstration work seems to support a more-complex system, yet there is no discussion of this provided by the proponent in the recent submissions. It seems that wherever detailed field testing, such as pumping tests and grouting testing have been undertaken, the data do not fit the simple relatively homogeneous unconfined aquifer conceptual model that is being proposed. Since there are groundwater springs that feed surface water courses located to the south of the proposed extraction areas, it is not unreasonable to require that the model be adapted to run in transient mode to show that it can simulate the seasonal variation that is observed in the groundwater/surface water system. Currently, only long-term steady state average groundwater conditions are modeled. It is recognized that developing a transient model will require significant effort; however, well-calibrated transient and steady-state models would provide confidence that the models can simulate observed field conditions. 11. If the two or three layer system is shown to be more-reflective of actual conditions, then the AMP testing and monitoring of the recharge system has to be rigorous enough to be able to confirm that water can be recharged into the various zones in the right quantities and right locations to protect all of the downgradient features/functions. More specifics 10/31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

13 Page 13 Garrod Pickfield LLP & Davis & Company October 28, 2008 are required with respect to how the proponent intends to define a successful demonstration of each recharge well. The AMP simply talks about a "measurable response" in adjacent recharge wells and in downgradient sentry wells (which are to be multi-level monitor nests). CLOSURE We trust that this information is of assistance to the Region of Peel and the Town of Caledon in their assessment of the Rockfort Quarry application by JDCL. Please contact our office if you have any questions. Yours truly, JAGGER HIMS LIMITED Andrew G. Hims, P.Eng Consulting Engineer AGH:nah Attachments: (i) Jagger Hims Limited June 18, 2001 Letter to Turkstra Mazza Associates: Rockfort Quarry Licence Application Peer Review Hydrogeological Aspects. File (ii) Jagger Hims Limited October 16, 2001 Letter to Turkstra Mazza Associates: Rockfort Quarry Application Peer Review Hydrogeological Aspects. File (iii) Jagger Hims Limited August 28, 2003 Letter jointly to Garrod Pickfield and Davis & Company: Rockfort Quarry Licence Application Peer review Hydrogeological Aspects Adaptive Management Plan Water Resources Protection. File (iv) Jagger Hims Limited September Letter jointly to Garrod Pickfield and Davis & Company: Rockfort Quarry Licence Application Peer review Hydrogeological Aspects Summary Statement. File /31/2008 2:02:58 PM C:\DOCUME~1\nhoran\LOCALS~1\Temp\XPgrpwise\AGH-L Preliminary Comments Oct doc

14 June 18, 2001 Turkstra Mazza Associates 221 Woolwich Street Guelph, Ontario N1H 3V4 Attention: Mr. Stephen Garrod Dear Sirs: Re: Rockfort Quarry Licence Application Peer Review Hydrogeological Aspects File We have completed a preliminary review of the identified reports that have been prepared by Conestoga-Rovers & Associates in support of the application for a licence for the proposed Rockfort Quarry. The enclosed information is provided to assist Region of Peel staff in their assessment of the application and technical issues arising that should be resolved with the proponent, as part of the review and approvals process under the Aggregate Resources Act. As part of our continued assessment of the hydrogeological aspects of the application, we have reviewed the following documents: (1) Water Resources Evaluation Volumes 1, 2 and 3. Rockfort Quarry Town of Caledon, Ontario. August Prepared by Conestoga-Rovers & Associates. Ref. No (1). (2) Adaptive Management Plan Water Resources Protection Rockfort Quarry Town Of Caledon. August Prepared by Conestoga-Rovers & Associates and Ecoplans Limited. Ref. No (5). 10/31/08 1:55 PM 98/0984/02/wp/AGH-L Peer Review

15 Page 2 Turkstra Mazza Associates June 18, 2001 (3) Preliminary Design Report Water Resources Mitigation Measures Rockfort Quarry Town Of Caledon, Ontario. October Prepared by Conestoga-Rovers & Associates. Ref. No (6). (4) Environmental Impact Assessment Proposed Rockfort Quarry Town OF Caledon Regional Municipality of Peel. August Prepared by Ecoplans Limited. File No. EC In addition, we have reviewed information provided by Harden Environmental Services Limited (Harden) in their document entitled Rockfort Quarry Application Response To Jagger Hims Limited Peer Review, dated April 6, We visited the site on August 27 th, 1999 to view rock cores from boreholes that had been drilled on and off site under the supervision of Harden. Photographs of the rock core were provided by Harden in their document entitled Rockfort Quarry Project Report On Site Investigations Volume 3-Core Photographs, dated Spring It is noted that Volumes 1 and 2 of that document were not provided for review. Our review focuses primarily on the revised design and operations plan for the proposed quarry, and the associated documentation prepared by Conestoga-Rovers & Associates (CRA), although the earlier work completed by Harden was referenced. A considerable amount of additional field investigations, monitoring, analysis and design were undertaken by the proponent s study team through 1999 and The knowledge base with respect to the physical setting of the site and the associated natural environment has been enhanced by the recent level of investigation and assessment. As a result of the new work, the proposed mining plan and mitigation measures have been modified from the original application, although the basic concept remains similar. Extraction of the bedrock resource will occur in phases in a dewatered quarry, with the exception of Phase 1 that will be extracted under water so that a reservoir of water can be maintained to supply the mitigation system and quarry operations. In order to minimize impacts on the ground water, surface water and aquatic habitat resources in the vicinity of the subject property, engineered mitigation measures are incorporated into the design and operation of the quarry. Those measures include grout curtain walls and a system of ground water recharge wells around the perimeter of the quarry, and soil buttresses against the inside of the final excavation to moderate the outflow of water from the lakes that will develop during the post-closure period. 10/31/08 1:55 PM 98/0984/02/wp/AGH-L Peer Review

16 Page 3 Turkstra Mazza Associates June 18, 2001 The majority of the impact assessment with respect to ground water and surface water resources, and the mitigation of potential impacts, is based on the computer model that was developed for the site and the surrounding area. The potential magnitude of the impacts that might occur without the benefit of engineered mitigation measures is not provided in the documentation, except to state that predicted impacts would be unacceptable. An integral component of the quarry operations as proposed will be an Adaptive Management Plan for the water resources mitigation measures. The report by CRA states on page 1 that The AMP method is based on a system of design, implementation, performance monitoring, evaluation, and optimization to ensure that the mitigation objectives are achieved. In simpler terms, the basic premise of the AMP appears to be that whatever actual physical conditions are encountered during the quarrying process, an appropriate level of monitoring and mitigation measures will be implemented to ensure that predetermined mitigation objectives and superior overall mitigation results are achieved (page 55 AMP report). Based on our review of the documents provided, the key to whether or not the quarry can be operated safely as proposed, and the natural environment protected as predicted, is going to be controlled by three main factors, as follows. (1) The actual quantity of water that will be required to operate the ground water recharge mitigation system of injection wells around the perimeter of the quarry as proposed, so that ground water resources and surface water resources adjacent to the site are maintained at existing levels. (2) The actual availability of water within the quarry property to sustain the recharge system throughout the operating life of the quarry and the post-closure period until the final lake levels are achieved. (3) The actual final lake levels that can be maintained through passive means at the end of the post-closure period, and how those lake levels will affect ground water and surface water resources adjacent to the quarry. The assessment that is presented contains several simplifying assumptions with respect to ground water movement through the rock mass, and the interaction between the ground water and surface water resources. The reality is that ground water movement through the fractured, layered bedrock aquifer is complex at the local scale. Ground water movement will be somewhat erratic, and will occur along preferred and discrete flow paths within the rock mass such as fractures and bedding planes, rather than the more consistent and 10/31/08 1:55 PM 98/0984/02/wp/AGH-L Peer Review

17 Page 4 Turkstra Mazza Associates June 18, 2001 predictable flow that occurs in sand and gravel aquifers. The interaction between the ground water and the surface water resources is similarly complex. Adjacent to the site, the surface water resources include spring-fed ponds and other spring areas, ephemeral, intermittent and perennial water courses, some of which receive ground water discharge through part or all of the year, and the associated aquatic habitat that includes a cold water fishery south of the site. Given this physical setting, there is a case to be made that the system is complex and may be sensitive to relatively small amounts of change. The simplifying assumptions that are adopted into the assessment, each of which tend to move the computer modeling assessment away from the actual physical conditions that prevail at the site, include the following. ASSUMPTION USED IN MODEL 1. The Amabel and the underlying Reynales bedrock act as a single hydrostratigraphic unit. The horizontal hydraulic conductivity of the full thickness of the unit at a specific location is characterized by a single value. Lateral variation is incorporated into the model. 2. The Amabel/Reynales unit is considered to behave as an equivalent porous medium (similar to a granular soil) that can be characterized by a single value for hydraulic conductivity. Ground water movement is considered to occur in a predictable manner through the pore space in the medium. 3. The computer model is based on a simple two-dimensional hydrostratigraphic conceptual characterization of the aquifer that does not allow for vertical heterogeneities in the rock mass. ACTUAL CONDITION 1. The Amabel is a layered bedrock formation that includes discrete beds that are separated by bedding plane discontinuities. The hydraulic conductivity characteristics will vary through the rock mass, both vertically and laterally. The Reynales Formation is recognized as a separate stratigraphic horizon from the Amabel that has different lithology and hydraulic conductivity characteristics. 2. The Amabel Formation is a fractured, layered bedrock aquifer. Ground water movement occurs along discrete and preferred flow paths that include the fracture and bedding plane discontinuities, and any solution channels that may be present in the rock mass. As such, ground water movement is more erratic and less predictable, particularly at the local scale, when compared to the porous medium characterization. 3. The Amabel is a complex three-dimensional aquifer that exhibits vertical heterogeneities within the rock mass. 10/31/08 1:55 PM 98/0984/02/wp/AGH-L Peer Review

18 Page 5 Turkstra Mazza Associates June 18, 2001 ASSUMPTION USED IN MODEL 4. The recharge well mitigation measures are modeled such that ground water levels in the bedrock are maintained at pre-extraction levels around the perimeter of the quarry. It is assumed that this will ensure that minimal change occurs with respect to the pattern of ground water discharge (location and quantity) to local watercourses, ponds and spring areas adjacent to the site. 5. The quantity of water that will be available to maintain the ground water recharge mitigation system, supply the aggregate processing requirements and fill the lakes following extraction is based on several assumptions as well as the computer simulations. 6. The closure plan assumes that the water level in the two lakes will achieve the elevations as modeled, and that ground water movement out of the quarry will result in similar flow patterns and ground water discharge areas as currently exists. ACTUAL CONDITION 4. The movement of ground water through the rock will be controlled by the degree of horizontal and vertical interconnectivity of the fractures and bedding planes. The ground water / surface water interactions with respect to vertical hydraulic gradient conditions at areas of ground water discharge have not been characterized/ quantified. The relationship between ground water levels and gradient conditions at the quarry and discharge conditions at the surface water locations has not been established in detail. 5. The availability of water will be a critical factor in the successful operation of the quarry. The water budget as presented demonstrates that there will be a fine balance between water availability and requirements, with little room for error. The sensitivity of the values used in the water budget has not been evaluated. 6. It is our understanding that the soil buttresses in the final quarry and the perimeter grout curtain wall will both be in place at the end of extraction. The ability to achieve the required hydraulic conductivity of the buttress/grout wall combination, so that ground water movement out of the quarry and the resulting discharge patterns maintain a similar flux and distribution as exists today, will be a difficult, but critical task. Further detail is required on how the permeability values will be achieved and evaluated, and what the sensitivity of the system will be with respect to ground water discharge patterns adjacent to the quarry. 10/31/08 1:55 PM 98/0984/02/wp/AGH-L Peer Review

19 Page 6 Turkstra Mazza Associates June 18, 2001 In summary, the proponent has undertaken additional field investigations, analysis and ground water modeling since the original application, and has prepared a revised design and operations plan for the quarry. In order for the quarry to operate as intended and not cause unacceptable impacts on local ground water and surface water resources, all of the engineering mitigation measures have to function as predicted. The availability of, and need for, water within the quarry will be a key factor through both the operating life and the post-closure period, and the water budget assessment indicates that there is little margin for error available. For example, at the end of Phase 5 the quarry dewatering system and other sources are predicted to provide million cubic metres of water per year, while the ground water recharge system will require about million cubic metres per year. A 10% contingency water use is incorporated into the assessment, leaving a surplus of 130,044 cubic metres per year to fill the quarry. Since this represents only about 1.2% of the water required for the recharge system, there is not a large comfort factor that surplus water will be available to fill the lakes given the inherent variability in the physical setting, and the assumptions that are used in the water budget assessment. Based on the above, it would be prudent that a comprehensive sensitivity assessment be completed that addresses the likely range of values for the various input parameters and assumptions that are used in the analysis and the computer simulations. This will provide the review agencies with an upper bound and lower bound assessment of potential impacts. Given the large amount of technical data that have been presented, we are in the process of preparing a series of detailed questions/comments that require clarification by the proponent. We will forward those detailed comments and questions as soon as they have been finalized. Please contact our office if you have any questions. Yours truly, JAGGER HIMS LIMITED Andrew G. Hims, P.Eng. Consulting Engineer AGH:jmm c. Simone Banz, Region of Peel 10/31/08 1:55 PM 98/0984/02/wp/AGH-L Peer Review

20 October 16, 2001 Turkstra Mazza Associates 221 Woolwich Street Guelph, Ontario N1H 3V4 Attention: Mr. Stephen Garrod Dear Sirs: Re: Rockfort Quarry Licence Application Peer Review Hydrogeological Aspects File Further to our summary letter dated June 18, 2001, we have compiled a series of detailed questions/comments that require clarification by the proponent. The questions/comments are provided in the attached Appendix, and are numbered for ease of response by the proponent. A copy of our June 18, 2001 letter is also provided in the Appendix for completeness. The enclosed information is provided to assist Region of Peel staff in their assessment of the application and technical issues arising that should be resolved with the proponent, as part of the review and approvals process under the Aggregate Resources Act. As part of our continued assessment of the hydrogeological aspects of the application, we have reviewed the following documents: (1) Water Resources Evaluation Volumes 1, 2 and 3. Rockfort Quarry Town of Caledon, Ontario. August Prepared by Conestoga-Rovers & Associates. Ref. No (1). (2) Adaptive Management Plan Water Resources Protection Rockfort Quarry Town Of Caledon. August Prepared by Conestoga-Rovers & Associates and Ecoplans Limited. Ref. No (5). 10/31/2008 1:53 PM 98/0984/02/wp/AGH-R Detailed Questions Oct 16

21 Page 2 Turkstra Mazza Associates October 16, 2001 (3) Preliminary Design Report Water Resources Mitigation Measures Rockfort Quarry Town Of Caledon, Ontario. October Prepared by Conestoga-Rovers & Associates. Ref. No (6). (4) Environmental Impact Assessment Proposed Rockfort Quarry Town OF Caledon Regional Municipality of Peel. August Prepared by Ecoplans Limited. File No. EC In addition, we have reviewed information provided by Harden Environmental Services Limited (Harden) in their document entitled Rockfort Quarry Application Response To Jagger Hims Limited Peer Review, dated April 6, We visited the site on August 27 th, 1999 to view rock cores from boreholes that had been drilled on and off site under the supervision of Harden. Photographs of the rock core were provided by Harden in their document entitled Rockfort Quarry Project Report On Site Investigations Volume 3-Core Photographs, dated Spring It is noted that Volumes 1 and 2 of that document were not provided for review. As with the initial review that was completed in December 1998, for the purpose of summarizing the results of our peer review, we have been asked to respond to the six questions listed below. Our response is provided foe each question. 1. Does the work that has been undertaken comply with the regulatory standards; that is, does it meet the minimum requirements of the Aggregate Resources Act? The hydrogeological study report does address all of the items listed in the Application Standards of the Aggregate Resources Act for a Category 2: Class A licence for a quarry operation which intends to extract aggregate material from below the established ground water table, Section 2.2 Technical Reports, Section and Hydrogeological Level 1 and Hydrogeological Level 2. The Application Standards indicate that for a Hydrogeological Level 2 Assessment, the technical report must address 14 items. The reports prepared by Conestoga-Rovers & Associates (CRA) address those 14 items. However, for the reasons outlined, we are not satisfied that these items have been addressed sufficiently to adequately characterize the hydrogeologic setting and the potential for adverse impacts. With respect to the local municipality, the Official Plan of the Town of Caledon and OPA 124 define the planning policies and guidelines that deal with Ecosystem Planning and Management to guide the land-use decision-making process. Section of the Official Plan deals with Performance Measures for ground water, and includes nine items that should 10/31/2008 1:53 PM 98/0984/02/wp/AGH-R Detailed Questions Oct 16