CRH Canada Group Inc. - Permit to take water

The City of Hamilton provided the following comments.

Comments received

1. The 2011 zone of influence (ZOI) which forms the basis of the water supply mitigation strategy should be revised to be conservative given the proposed dewatering depth is below the depth tested during the 2014 pumping test. It is recommended that MECP investigate this further, ensuring the applicant has conservatively extrapolated the ZOI and its impacts accordingly.

Response

It appears that the City’s formulated their comments based on the site plan amendment application that they reviewed in 2019. Their comment to Wellhead Protection Area (WHPA) assessment is not relevant here because the applicant has not requested nor does the ministry considering increase in taking which has been previously permitted to CRH. If the City’s source water concerns at the stage of site plan amendment has not been addressed by CRH, the City should raise their concerns directly with CRH. The PTTW is not a process to settle/address concerns which have been previously agreed upon among stakeholders during various regulatory approvals. According to MECP-GIS mapping, there is a linear distance of about 2.4 km between the southern edge of the site and the northern edge of the mapped WHPA-D of the Greensville municipal well field. The estimated zone of influence (ZOI) extends about 1.2 km from Sump 2 and 700 m from the site boundary. The hydraulic interaction between the bedrock aquifer at the site and Greensville municipal well field is not expected. In this regard, I do not believe additional assessment is needed to assess the impact of groundwater taking on the Greensville municipal well field.

As indicated above, this is not a new taking and there is no increase in taking to the amount which has previously been permitted. An additional hydraulic stress on the bedrock groundwater system is not expected. As a result, re-evaluation of the ZOI is not needed. The 2017-2018 hydraulic data provided in Appendix E does not suggest abnormal changes in water elevation across the site. The water elevations in various bedrock units appear to be stable and mainly influenced by precipitation.

2. In addition to MECP/MNRF notification, the City would like to be notified of any water well interference complaint and its associated mitigation measures. We recommend to be included in the Permit To Take Water approval.

Response

The city of Hamilton will receive the annual monitoring report that the client is required to submit, included in these reports will be any interference complaint that is received.

3. The City would like to be circulated on all annual monitoring reports submitted to MECP and/or MNRF. We recommend that this becomes a condition of the Permit To Take Water approval.

Addressed with the condition below

The permit holder shall submit to the director after every 5 years and/or at the time of renewal or amendment to the permit a monitoring report containing hydraulic data to be acquired as per Condition 4.3 and its interpretations. In addition, the permit holder shall by April 30th each year, submit an annual monitoring report electronically to:

The City of Hamilton
Source Water Protection, Water & Wastewater Systems Planning
Attention: Carmen Vega, Senior Project Manager

The initial annual monitoring report shall be due by April 30, 2020.

4. Manual monthly measurements in the monitoring network are insufficient – continuous monitoring through dataloggers should be employed to better inform MECP and the applicant if increased interference complaints arise.

Response

According to Appendix E, the applicant currently monitors water level manually as per Permit To Take Water requirements with the exception of continuous monitoring at one location on a voluntary basis. In addition to the Permit To Take Water mandated manual monitoring, CRH monitor water levels at 20 plus locations. Since there was no water quantity complaint received in 2017-2018, the existing monitoring network as well as monitoring frequency appear to be adequate for assessing spatial and temporal trend analysis for water quantity interference issues.

5. A new water well survey should be conducted prior to approval or as a condition of approval to ensure that if quarry deepening has broader water supply impacts on private well owners, baseline monitoring can be undertaken and water supply mitigation plans can be addressed if impacts/complaints arise.

Addressed with the condition below

The permit holder shall conduct a water well survey within 1,000 m of the sources listed in Table A every five years commencing in 2024.

6. Monitoring well depths primarily seem to be above the lowest depth of extraction. It is recommended that monitoring wells be deepened or new wells drilled which fall below the newly deepened zone that is being proposed (i.e. wells should be installed below 220 m ASL) to better characterize impacts. Table 4.1 shows well bottom elevations and well screen elevations typically above 230 m ASL.

Response

Current monitoring network is deemed adequate in providing hydraulic data for the bedrock unit below the approved extraction depth.