1 Module 4 Control measures risk reassessment Session

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Module 4 Control measures & risk reassessment Session structure • Overview • Definition & examples • Actions • Outputs • Challenges • Exercises 2

Module 4 Control measures & risk reassessment Overview • Document existing and potential control measures • Assess their effectiveness (validation) • Recalculate risks accounting for existing control measures • Prioritize risks 3

Module 4 Control measures & risk reassessment Control measure definition: Any action or activity that can be used to prevent, eliminate or reduce to an acceptable level any water safety hazard 4

Module 4 Control measures & risk reassessment Examples – Control measures – low tech Cover Well head Designated bucket 5

Module 4 Control measures & risk reassessment Examples – Control measures Automated chlorine dosing system Source water protected from livestock 6

Module 4 Control measures & risk reassessment Actions • Identify existing controls • Document need for new control measures as necessary Identify control measures Assess effectiveness Reassess risks Prioritize risks 7

Module 4 Control measures & risk reassessment Actions continued. . . • Assess effectiveness (normal & exceptional circumstances) Validation Investigative activity to identify the effectiveness of control measures. It provides the evidence that elements of the WSP can effectively meet the water quality targets. 8

Module 4 Control measures & risk reassessment Actions continued. . . • Assess effectiveness (normal & exceptional circumstances) • Monitoring • Not in isolation but as part of process chain • Data from studies / historical records • Introducing contaminant – testing removal • Sanitary surveys 9

Module 4 Control measures & risk reassessment Actions continued. . . • Reassess risks accounting for effectiveness of control measures • Based on long-term average performance • Highlight where controls are not in place 10

Module 4 Control measures & risk reassessment Actions continued. . . • Prioritize all identified risks • Rank the reassessed risks • Screen for critical risks 11

Module 4 Control measures & risk reassessment Outputs Validation of control measures Identification of control measures Prioritization of risks Module 4 12

Module 4 Control measures & risk reassessment Challenges • Uncertainty in prioritizing risks • Lack of knowledge • Poor data • Different approaches = different outcome • Qualitative versus quantitative • Assessing effectiveness of certain controls • Catchment – how to measure/enforce? 13

Module 4 Control measures & risk reassessment Exercise • In small groups • Part 1 (5 minutes) • Match up hazardous events with suitable control measures • Identify possible control measures for three hazardous events • Part 2 (5 minutes) • Describe how these control measures can be validated • Part 3 and 4 (20 minutes) • Reassess the likelihood and severity by considering the implementation of control measures and rank the risks again from highest to lowest 14