Module 6 – Assessing Risk to Drinking Water

Assessment Reports Module

Module 6 – Assessing Risks to Water Quality and Quantity – Assessment Reports

“Either we change our approach or we risk destroying the resource.”

– Speaker at water conference

Learning Expectations

By the end of this session you should be able to:

  • Understand the concepts of risk, risk assessment, risk management and cumulative risk
  • Explain the formula for risk
  • Understand the process of risk management and of the various approaches, strategies and measures for managing risk
  • Appreciate some of the socio-economic issues and challenges related to apportioning responsibility and costs of risk management
  • Understand vulnerable areas analysis is done as part of semi-quantitative risk assessment
  • Generally understand how the threats inventory process works and how this fits into the development of the Assessment Reports

Section One – Module Content

Learning Expectations and Activities

Unit 1 – What is Risk Assessment?
Identifying risk
Assessing risk
Ranking risk

Unit 2 – What is Risk Management?
Overview
How are water quality risks managed, in six easy steps
Categorizing risk management measures
Strategies in risk management
What should we do with water quality threats? Making choices

Unit 3 – Challenges and Questions
Whose responsibility is risk management?
What’s fair and what’s cost-effective?

Unit 4 – Wrapping It Up
Review: Risk management in the drinking water source protection planning process
Field Learning
Self-assessment on learning goals
More help
Logging and Linking: Next steps, continuing questions and unresolved issues

Chapter 2.3 of the Maitland Valley and Ausable Bayfield Assessment Reports is called Water Quality and Quantity.

Chapter 4 of the Maitland Valley and Ausable Bayfield Assessment Reports is called Vulnerability, Threats and Risks.

Chapter 6 of the Maitland Valley and Ausable Bayfield Assessment Reports is called Future Work.

Source Protection Plan Chapter 3 is called Establishment of Source Protection Policy Areas.

Activity 1 – Group Dialogue

Title: How we’re providing barriers of protection

Based on your field learning assignment from last module, share some of the general class threats with which your sector is familiar.

Share how your sector is reducing the likelihood of a threat from contaminating drinking water and some measures contemplated for the future to provide additional barriers of protection.

Activity 2 – Small Group or Pair Activity

Title: ‘Risk Quiz’

This is the second of two modules related to drinking water threats and risks under the source protection planning process. You learned in the previous module some basic concepts related to drinking water threats, risks, concerns and issues. This module you will learn some more detail about what’s involved in the risk assessment process.

Let’s first do a quick review of some concepts from last module.

Review the meanings of drinking water threats and drinking water risks. Then work to complete the following quiz:

  1. A drinking water risk means the same thing as a drinking water threat.

TRUE FALSE

  1. a) A drinking water risk exists around a sinkhole regardless of land use activities around it.

TRUE FALSE

b) Why?

  1. A drinking water ____________ has to do with the likelihood a contaminant will be delivered to a drinking water source.
  2. Which is more likely to require action on the part of a landowner or a person engaged in an activity: the identification of a drinking water risk or the presence of a drinking water threat? Discuss.
  3. Which is more likely to require action on the part of a landowner: the identification of a drinking water risk or the identification of an activity that is a significant threat to drinking water sources? Discuss.

Unit 1 – What is Risk Assessment?

Activity 3 – Multimedia Presentation – Title: Identifying, Assessing and Ranking Risk

View a multimedia presentation prepared by Kevin McKague, Water Resources Engineer with the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) dealing with drinking water risks.

As you watch the presentation take note of some of the content which will help you answer the questions below.

  1. Drinking Water Risk Assessment _ X =

  1. Threats X _______ = Risk
  2. ______ Score X Vulnerability Score = Risk Score
  3. What is cumulative risk?
  4. Notes from presentation:

Activity 4 – Small Group or Pair Activity – Title: Where is risk highest?

In pairs or small groups, take a look at two cases of service stations that have fuel storage.

Which service station has higher drinking water risk?

Service Station A ‘Gus’s Gas’

This service station has an underground storage tank that holds 1,200 gallons of petroleum. The tank is 30 years old.

Service Station B ‘Patty’s Petrol’

This service station has an underground storage tank that holds 1,200 gallons of petroleum. The tank is 30 years old.

Is there any difference between the ‘threat’ posed by Service Station A and that posed by Service Station B?

Yes or No.

What is the ‘threat’ identified here?

What is the ‘contaminant of concern’?

What about risk?

Which activity poses a higher risk to municipal drinking water sources?

Service Station A

Service station A is located within the 25-year time-of-travel (ToT) zone around the municipal well.

Has many feet of loam and clay and has been mapped as having low intrinsic susceptibility under the Intrinsic Susceptibility Index (ISI)

Service Station B

Service station B is located inside the two-year time-of-travel zone of the municipal well (WHPA B).

In the middle of a sinkhole cluster, shallow, no clay, rated high under ISI mapping.

Is the vulnerability score high or low in each case?

Which service station poses the greatest risk?

Share with the larger group.

Risk assessment

Activity 5 – Personal Reflection – Title: Risk Quiz

Based on information from your facilitator or presenter answer the following question:

  1. Risk assessment . . .

a). . . . only determines whether a risk is present or not. TRUE FALSE

b) . . . applies only where current drinking water sources are at risk.
TRUE FALSE

c) . . . guides our priorities in taking action because risk assessment grades
the risk to water quality. TRUE FALSE

Activity 6 – Small Group Activity – Title: Case study of drinking water threat

Consider at a ‘case-study’ threat and some of the considerations related to that threat.

The facilitator will provide a different sample threat to each individual group.

Within your small groups share some thoughts on the threat and its relationships and hazards and whether it should enter the risk assessment stream.

Share your thinking with the larger group.

Unit 2 – How are drinking water risks managed?

Activity 7 – Presentation – Title: Drinking Water Risk Management

Imagine that the Drinking Water Risk Assessment is a score card in a game of golf.

This will give you a score.

But, it won’t tell you how to lower the score.

How do we lower the score?

In golf we may ask for a lesson from the resident pro.

In protection of our water quality, we use risk management.

  1. What is Drinking Water Risk Management?

Test your knowledge of Drinking Water Risk Management by answering the following question:

  1. Risk management involves . . .

a) . . . reducing the risk. TRUE FALSE

b) . . . maintaining the risk level. TRUE FALSE

c) . . . monitoring risks for change. TRUE FALSE

d) . . . any of the above . . . TRUE FALSE

  1. Drinking water risks may be managed in the following six steps:
  2. _______________________________________________________

Activity 8 – Small Group Activity – Title: Making choices

What should we do with drinking water threats?

We may identify a threat, and then assess that there is also vulnerability, turning the threat into a risk.

What can we do to mitigate against that threat so it does not become a high risk (significant threat to drinking water sources) (A score of 80+)?

In your small break-out group, look at one or several ‘risks’ and proposed some mitigations or management responses to the risk.

Share some of your ideas with the larger group.

Risk Management

(Examples below are in no particular order)

Land Activity Risk

Suggested Management of Risk

  1. Oil and Gas Wells – Potential two-direction pathway:

a) oil, gas, brine can travel upward into aquifer or surface water.

b) Surface contamination has direct pathway to aquifer.

  1. Aggregate extraction – Removal of overburden filtering material. Exposure of water table.
  2. Above-ground and underground storage tanks. (Please consult Tables of Threats and Circumstances.)
  3. Chemicals in widespread use. Users unaware of potential risks.
  4. Wide range of business activities many in vulnerable areas carrying unknown risks to water supplies. Scale creates concern.
  5. Pesticide use
  6. Past land uses or conditions (e.g. landfills, industries, gas stations etc.) may be source of risks.
  7. Waste Disposal Facilities
  8. Biosolids (from Wastewater/Sewage Treatment Plants, etc.) and treated septage is beneficial to land but some concerns re pathogens, PCBs arise.
  9. Manure/fertilizer storage
  10. Manure/fertilizer application
  11. Older septic systems
  12. Use of road Salts/De-icing compounds
  13. Urban runoff is source of numerous pollutants.
  14. Direct waster water discharge and overflows are a threat.
  15. Land drainage (Present process does not consider drinking water source protection.)
  16. Numerous Take Water permits (6,000 in Ontario).

No database, no information on impacts.

  1. Other …

Unit 3 – Wrapping it up – Challenges and Questions

Activity 9 – Group Dialogue – Title: What is effective at mitigating risk?

  1. Discuss existing, effective ways risk is mitigated.

a) _____________________________________________________

b) _____________________________________________________

c) _____________________________________________________

  1. Discuss other potentially effective risk mitigation strategies which should be investigated further or introduced.

a) _____________________________________________________

b) _____________________________________________________

c) _____________________________________________________

  1. What is cost-effective at mitigating risk? Discuss.

a) _____________________________________________________

b) _____________________________________________________

c) _____________________________________________________

  1. What is not cost-effective at mitigating risk? Discuss.

a) _____________________________________________________

b) _____________________________________________________

c) _____________________________________________________

  1. What are some of the benefits of risk management? (To a business; an individual; the water users; the community)

a) _____________________________________________________

b) _____________________________________________________

c) _____________________________________________________

  1. What would motivate individuals or businesses in your sector to incorporate risk management?

a) _____________________________________________________

b) _____________________________________________________

c) _____________________________________________________

  1. What are some of the barriers which might discourage individuals or businesses in your sector from incorporating risk management?

a) _____________________________________________________

b) _____________________________________________________

c) _____________________________________________________

For information on risk management plans for individual properties please visit the Risk Management Office page at sourcewaterinfo.on.ca.

Self-assessment on learning goals

More help

Do you want more information? Do you want to learn more? Your facilitator is prepared to discuss any topic or question with the goal of helping you move to the next module. Alternatively, write down your thoughts and facilitator will follow up with you.

Logging and Linking: Next steps, continuing questions and unresolved issues

What questions do you have?

SECTION TWO – Priming the Pump

Notes, Definitions, Fact sheets

[The following information is draft at time of printing – this is for local education purposes. Please consult most recent Ontario Ministry of the
Environment, Conservation and Parks (MECP) guidance for pertinent current applicable regulation, guidance and direction].

Please consult the Provincial Tables of Threats and Circumstances.

The following are phases of drinking water source protection planning:
Scientific research
Planning
Monitoring
Evaluation of success

Scope and Purpose of the Assessment Reports

The main purpose of an assessment report is to prioritize drinking water issues and threats within vulnerable areas.

Assessing Risks to Water Quality and Quantity

Drinking water threats can become drinking water risks when the factor of Drinking Water Vulnerability is added into the equation.

When a threat is assessed as a risk then we must consider how that risk will be managed through Drinking Water Risk Management.

Here is an approach offered ‘in six easy steps’ to manage risks to our drinking water:

  1. Decide on and describe the required outcome.
  2. Identify, and adopt the measure(s) to mitigate the risk, describing how the measure will achieve the desired outcome.
  3. Identify the agency and/or persons responsible for applying the mitigating measure.
  4. If applicable, estimate the cost.
  5. Budget for its completion. Set the completion date.
  6. Specify the kind and duration of monitoring of the measure (and by definition monitoring the measure includes monitoring of the risk and evaluating the measure).

Aggregate Risk

Aggregate Risk refers to multiple risks in a municipal water supply protection area that are considered together relative to the overall risk to drinking water sources.

Contaminant of concern

A contaminant of concern is a chemical or pathogen that is, or may be, discharged from a drinking water threat as defined by the Ontario Ministry of the Environment, Conservation and Parks (MECP).

Drinking Water Concern

A possible drinking water issue that has not been substantiated by monitoring, or other verification methods, will be identified through consultations with the public, stakeholder groups and technical experts (e.g., water treatment plant operators).

Drinking Water Risk

A drinking water risk is the likelihood of a drinking water threat

a) rendering an existing or planned drinking water source impaired, unusable or unsustainable, or;

(b) compromising the effectiveness of a drinking water treatment process, resulting in the potential for adverse human health effects.

Drinking Water Threat

A drinking water threat is an existing or possibly future activity or existing condition that results from a past activity that,

a) adversely affects or has the potential to adversely affect the quality or quantity of any water that is or may be used as a source of drinking water or,

b) that results in or has the potential to result in the raw water supply of an existing or planned drinking water system failing to meet any standards
prescribed by the regulations respecting the quality or quantity of water and includes an activity or condition that is prescribed by the regulations as a drinking water threat.

Risk Assessment

A Risk Assessment is an assessment of risks prepared in accordance with the regulations and the rules.

(An assessment of drinking water threats in the Assessment Report is different than a risk assessment that is conducted to update or verify vulnerable area mapping).

Please consult the Act and the regulations for meanings.

Risk Management Plan

A risk management plan, or RMP, means a plan for reducing a risk prepared in accordance with the regulations and the rules. Visit the Risk Management Office page to learn more.

Semi-Quantitative Risk Analysis

Describes an approach or methodology that uses measurable or ranked data, derived from both quantitative and qualitative assessments, to produce numerical values to articulate results.

Significant Drinking Water Threat

A significant threat to municipal drinking water sources is an activity that, according to assessment, poses or has the potential to pose a significant risk and scores 80+.

Threat Assessment, Tier One

Threat Assessment, Tier One, is a preliminary examination of a drinking water threat based on readily accessible information.

Threat Assessment, Tier Two

A Threat Assessment, Tier Two, is an advanced examination of a drinking water threat through assessing more detailed information, interviews and perhaps, when warranted, additional monitoring, modeling and studies.

SECTION THREE

Handouts, additional readings, field learning assignments, findings

Reading, Viewing and Listening Resources:

Ontario Ministry of the Environment, Conservation and Parks Technical Guidance Modules for Assessment Report, particularly Module 6, Water Quality Risk Assessment Separate Pullout.

Your Evaluation of Group Performance

How do you rate this session?

How interesting was the material to you?

(Please circle the one that best describes your perspective).

Not interesting at all Not very interesting No opinion Interesting Very interesting

How involved did you feel?

Not at all involved Not very involved No opinion Somewhat involved Very involved

What parts of the session did you think were weak?

What parts of the session did you think were strong?

Group Performance Goals

How well did this group achieve its goals this session?

Group Goal Achievement

How well was this goal achieved?
(Please circle one)

Write goal here:

(Not at all) (Only a little bit) (No opinion) (Somewhat
well) (Very well)

How could we do a better job of achieving this goal?

Write goal here:

(Not at all) (Only a little bit) (No opinion) (Somewhat
well) (Very well)

How could we do a better job of achieving this goal?

Write goal here:

(Not at all) (Only a little bit) (No opinion) (Somewhat
well) (Very well)

How could we do a better job of achieving this goal?

Write goal here:

(Not at all) (Only a little bit) (No opinion) (Somewhat
well) (Very well)

How could we do a better job of achieving this goal?

Write goal here:

(Not at all) (Only a little bit) (No opinion) (Somewhat
well) (Very well)

How could we do a better job of achieving this goal?

Write goal here:

(Not at all) (Only a little bit) (No opinion) (Somewhat
well) (Very well)

How could we do a better job of achieving this goal?

Do you have any other feedback, input, concerns, question or comments about the working group performance or process?

Thank you for your important feedback.

A summary assessment will be completed and a report will be presented to the group at the beginning of next session.

Field Learning Assignment

Record the findings from your field learning assignment here.

Find the location of your nearest municipal supply of drinking water, whether an intake or a wellhead.

Drive or walk for several minutes away from that location and make a list of the land use activities and drinking water threats (e.g., gasoline storage,
pesticide, etc.) you find.

Remember, any information you share should be by class only – avoid information that identifies a specific individual or enterprise.
Did you notice examples of good management to protect our sources of water?
What best management practices did you find?
What questions or concerns do you have?
How could the activities be managed to prevent risk to drinking water sources?
Did you see examples of good management to protect our sources of water?

Report back to the group.

Information here is provisional, subject to change, and posted for local
information and education purposes. For current information visit Ontario.ca and sourcewaterinfo.on.ca. We would like to acknowledge the support of the Government of Ontario. Such support does not indicate endorsement of the contents of this material.

© Active Learning Program 2019