Test holes and dewatering wells - Requirements and best management practices

Note: The numbers and details presented in this manual are current as of the date of publication. Any new regulation or legislation that has been written or revised following this date takes precedence over what is stated here.

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Master Table of Contents

The following is a list of each chapter in the Test Holes and Dewatering Wells – Requirements and Best Management Practices manual including chapter number followed by complete chapter title.

1. Introduction

2. Definitions & Clarifications

3. Exemptions: Wells, Activities & Experienced Professionals

4. Well Contractors & Well Technicians – Licences, Responsibilities & Exemptions

5. Siting Considerations & Initial Planning

6. Constructing the Hole, Casing & Covering the Test Hole or Dewatering Well

7. Annular Space & Sealing

8. Multi-level Monitoring Test Holes

9. Completing the Test Hole or Dewatering Well Structure

10. Test Hole & Dewatering Well Exemption & Recommended Activity: Disinfection

11. Flowing Test Holes & Dewatering Wells

12. Equipment Installation

13. Water Level Measurements, Aquifer Testing & Discharge Water Handling

14. Test Hole & Dewatering Well Maintenance & Repair

15. Well Records, Documentation, Reporting & Tagging

16. Abandonment: When to Plug & Seal Test Holes & Dewatering Wells

17. Abandonment: How to Plug & Seal Test Holes & Dewatering Wells

Glossary

Ontario Legislation

Resources

Purpose

The intention of this manual is two-fold. First it provides quick access to a simplified, clear and concise discussion of Regulation 903 of the Revised Regulations of Ontario, 1990 (Wells) made under the Ontario Water Resources Act (the Wells Regulation^{footnote 1[1]}). Second it provides best management practices and recommended techniques that help a person constructing a test hole or dewatering well to go beyond the minimum requirements set by the Wells Regulation. In this manual, best management practices are recommended actions or steps that exceed the minimum regulatory requirements to better protect the groundwater and the natural environment. In the case of any discrepancies between this guidance and the Wells Regulation, it is the Wells Regulation and the Ontario Water Resources Act which take precedence.

The best management practices presented in this manual are intended to provide a practice or combination of practices based on research, field-experience, and expert review, which are both effective and practical for test holes and dewatering wells as defined in the Wells Regulation. A separate manual has been provided for water supply wells titled Water Supply Wells – Requirements and Best Management Practices.

A properly designed and installed groundwater test hole or dewatering well provides essential information about the geological and hydraulic properties of a formation; potentiometric surface of a particular hydrogeologic unit; water quality with respect to various indicator parameters and water chemistry with respect to a contaminant release; water pumping and treatment as well as water removal for construction projects and quarries.^{footnote 2[2]}

In some cases, ponds, reservoirs, lagoons, artificial wetlands, canals, trenches, tile drains, wick drains or ditches meet the definition of wells in the Ontario Water Resources Act. The Wells Regulation provides exemptions for these types of wells and this manual provides further descriptions of these wells.

The terms “test hole” and “dewatering well” do not include any well that is used or intended for use in the future as a source of water for agriculture or human consumption. A well, other than a test hole or dewatering well as defined in the Wells Regulation or a well exempted by the Wells Regulation, must comply with the Wells Regulation requirements covered in the Water Supply Wells: Requirements and Best Management Practices manual.

How to use this manual

Each chapter in this manual is based on a specific topic of the well construction process. The Table of Contents found prior to this page indicates the chapter titles. The chapters are divided by tabs for quick reference.

This manual should be used on the job and/or at the office to better understand, confirm and follow the requirements of the Wells Regulation and apply recommended best management practices.

Elements Included

Each chapter in this manual includes the following:

• Table of Contents – Identifies sections, sub-sections, figures, and tables found within the chapters.
• Chapter Description – Describes the purpose of the chapter and gives an overall summary of the content covered within the chapter
• Regulatory Requirements – Summarizes the minimum requirements relevant to the chapter content
  • Relevant Sections – The Wells Regulation – Lists the sections of the regulation that are relevant and referenced within the chapter
  • The Requirements – Plainly Stated – Provides a “basic terms” summary of the requirements laid out in the Wells Regulation
  • Relevant Sections – Additional Regulations or Legislation – Lists additional sections of regulations or legislation that are relevant and referenced within the chapter
  • Relevant Standards – Lists additional standards that are relevant and referenced within the chapter
• Key Concepts – Provides an overview of the processes, procedures and the best management practices for completing the task(s) set out in the chapter. The Key Concepts are expanded upon in the chapters.
• Detailed Information – Expands upon the Key Concepts and provides best management practices
• Tools – Where appropriate, provides tools that may be helpful on the job when completing the task(s) relevant to the chapter

The manual also includes the following:

• Glossary – Provides a list of relevant terms and their definitions
• Ontario Legislation Section - Contains the following:
  • Ontario Water Resources – Provides the current version of the sections of the Ontario Water Resources Act relevant to wells
  • The Wells Regulation – Provides the current version of the Wells Regulation
• Resources – Provides quick access to important contact information and additional related resources

Word Descriptions

The following words are used throughout the manual for easy reference.

The Wells Regulation

indicates specific references to requirements.

Best Management Practice

indicates a best management practice.

Definition

indicates the definition of a term.

Reminder

indicates a reminder or note regarding important information.

Records of Site Condition Regulation

indicates an O. Reg. 153/04 regulatory requirement or information.

Role of the Legislation and Regulations

Whenever an activity involves impacts or potential impacts to the environment, a wide range of regulations are usually present at all levels of government.

• Impairment to any part of the natural environment has the potential to impact wildlife as well as human health and safety
• Environmental damage can exist in many forms including liquid waste in lakes, improper application of pesticides sprayed on food crops, excessive discharge of exhaust material into the atmosphere, entry of surface water or other foreign material into a well
• Environmental protection includes the protection of human health and public safety, as well as that of all living things
• It is a good business practice and good for everyone, to go beyond the minimum compliance requirements, that is – beyond the minimum standard

Legislation Relevant to Test Holes & Dewatering Wells: An Overview

Reference is made throughout this manual to the Ontario Water Resource Act (OWRA).

Well construction in Ontario is governed by the Ontario Water Resources Act and the Wells Regulation (Regulation 903). Some test holes and monitoring wells are also subject to the requirements of the Records of Site Condition Regulation (O. Reg. 153/04 as amended). The Ministry of the Environment and Climate Change’s (MOECC) legislative authority to regulate water comes primarily from two acts, the OWRA and the Environmental Protection Act (EPA).

The purpose of the OWRA is to provide for the conservation, protection and management of Ontario’s waters and for their efficient and sustainable use, in order to promote Ontario’s long-term environmental, social and economic well-being. The OWRA, which gives the MOECC extensive powers to regulate water supply, sewage disposal and to control sources of water pollution, expressly states that for the purpose of the Act, the Minister has the supervision of all surface and groundwaters in Ontario.

The EPA prohibits the discharge of contaminants to the natural environment, including water except where specifically permitted by an environmental compliance approval. The goals, policies, and guidelines set out in this document assist persons making decisions under or related to these Acts. They give, for example, directions that assist in defining site-specific effluent limits, which then may be incorporated into environmental compliance approvals or control orders. These control documents are issued under the authority of the legislation, and thus become legally binding and constitute the basis for compliance and enforcement actions. The policies and guidelines that are not incorporated into regulation or legislation by reference, do not have any formal legal status but, by their successful use over the years, are now seen as standard practices for water resources management.

There are many other important aspects of water management that do not fall under the jurisdiction of the MOECC, but are the responsibility of other provincial ministries and federal government departments, most notably the Ontario Ministries of Natural Resources, Health and Long Term Care, Agriculture Food and Rural Affairs, Conservation Authorities and the Federal Departments of Fisheries and Oceans and Environment Canada.

The Ontario Water Resources Act also sets out the consequences for non-compliance with the Act and the Wells Regulation.

The Wells Regulation: An Overview

The Wells Regulation helps to ensure that groundwater quality, well water quality, and the environment are protected:

• The elements contained in the Wells Regulation are aimed at protection – of the resource, the well owner, the industry, and the well water
• The Wells Regulation identifies what must be done by the well contractor and the well technician to ensure that well construction activities:
  • Protect aquifers and water resources
  • Protect aquitards
  • Protect water quality and quantity
  • Protect the health and safety of the well owner and users
  • Establish minimum standards for carrying out the elements of the work that have potential to have an impact on the well, the environment, human health and the owner

The Wells Regulation covers:

• Qualifications and requirements for obtaining and maintaining both well contractor and well technician licences
• Required steps before work on the well begins
• Required steps during the well construction process
• Approved materials and steps relating to casing, well screens, sealant, disinfection and pumping test
• Required steps for sealing the annular space
• Required steps to take after the well construction is complete such as notifications (e.g. tags and records)
• Requirements for when to abandon a well and how to seal a well
• Well owner’s responsibilities
• Exemptions for certain types of excavations, activities, persons and shallow works

Protecting the Environment

A condition of both the well technician licence and the well contractor licence is that these licence holders must comply with all of the provisions of the legislation and Wells Regulation at all relevant times. Also, any other person working on a well must also comply with the legislation and the Wells Regulation. It is important to understand that carelessness or cost cutting during well construction and maintenance, costs everyone.

The nature of an aquifer makes it difficult, if not impossible to repair. Cleanup, if it is even possible, is very costly and positive results can take years to achieve. Remember that a single well can contaminate an entire aquifer, and affect the lives of many people.

The Wells Regulation and other legislation related to wells benefit all of the people of Ontario.

It is a privilege and a responsibility to be a guardian or steward of water, which is the basis of the livelihoods of licensed well technicians and other professionals. Each of us must do our part to protect groundwater from contamination, and all harmful practices.

Key Message

The Wells Regulation sets out the minimum requirements for well construction. It is a good idea to exceed these minimums where the professional judgment of the person constructing the well indicates that more is needed. During construction, situations may be identified where it may be beneficial to exceed the requirements to better protect the natural environment.

Exemptions

The Wells Regulation applies to all wells as defined by the Ontario Water Resources Act, except where the Wells Regulation explicitly provides an exemption. These exemptions are specifically addressed within this manual as follows:

• Summary of exemptions – see Chapter 3: Exemptions: Wells, Activities & Experienced Professionals
• Licensing for professionals – see Chapter 4: Well Contractors & Well Technicians – Licences, Responsibilities & Exemptions
• Siting and setback distances – see Chapter 5: Siting Considerations & Initial Planning
• Construction method, material and activity – see Chapter 6: Constructing the Hole, Casing & Covering the Test Hole & Dewatering Well
• Annular space – see Chapter 7: Annular Space & Sealing
• Material and annular space for multi-level monitoring test holes – Chapter 8: Multi-Level Monitoring Test Holes
• Disinfection – see Chapter 10: Test Hole & Dewatering Well Exemption & Recommended Activity: Disinfection
• Equipment installation – see Chapter 12: Equipment Installation
• Yield test – see Chapter 13: Water Level Measurements & Groundwater Sampling
• Abandonment – see Chapter 16: Abandonment: When to Plug & Seal a Test Hole or Dewatering Well

Records of Site Condition Regulation: While the Wells Regulation exempts test holes and dewatering wells from some requirements, the Records of Site Condition regulation (O. Reg. 153/04) stipulates that some of these exemptions do not apply to a monitoring well installed for the purpose of a phase one environmental site assessment and a phase two environmental site assessment completed under that regulation. See subsection 22(4) of O. Reg. 153/04:

The provisions of the Ontario Water Resources Act and of Regulation 903 of the Revised Regulations of Ontario, 1990 (Wells) made under that Act, that would apply to a test hole but for section 1.1, and subsections 13 (2), 14.1 (2), 14.2 (3), 14.3 (2), 14.4 (4) and 14.5 (3) of that regulation, apply to a monitoring well installed for the purpose of,

1. a phase one environmental site assessment; and
2. a phase two environmental site assessment. O. Reg. 511/09, s. 14.

Chapters 3: Exemptions: Wells, Activities & Experienced Professionals, Chapter 6: Constructing the Hole, Casing & Covering the Test Hole & Dewatering Well and Chapter 7: Annular Space & Sealing provide further information.

Penalties for Failing to Comply with Wells Regulation and Licensing Requirements

General penalties for an individual’s non-compliance with a requirement of the Ontario Water Resources Act or the Wells Regulation include a maximum fine of $50,000 for each day or part of day on which the offence occurs or continues for the first conviction and $100,000 for each day or part of day on which the offence occurs or continues for each subsequent conviction and imprisonment for up to one year.

Corporate penalties for non-compliance with a requirement of the Ontario Water Resources Act or the Wells Regulation include a maximum fine of $250,000 for each day or part of day on which the offence occurs or continues for the first conviction and $500,000 for each day or part of day on which the offence occurs or continues for each subsequent conviction.