Risk management examples

Ben identifies several climate hazards that could be relevant to his activities including:

• heatwaves and extreme heat
• drought
• extreme rainfall leading to flash flooding
• storm events.

Ben has used the following guidelines:

• Guideline for assessing and minimising air pollution in Victoria
• Reducing risk in the premixed concrete industry
• Guidance for Assessing Nuisance Dust.

He considers each climate hazard. He considers how hazards from concrete batching could be made worse by climate change (see Implementing controls below).

To understand possible future climate change, Ben looks at:

• VCSR24
• Greater Melbourne Climate Projections 2024 Regional Summary.

Given the 15-year design life of the plant, he looked at projections for 2050. He found:

• Victoria is virtually certain to experience hotter and more frequent hot days. In particular:
  • Melbourne is expected to experience between 3-10 hot days per year over 37 °C by 2050. This is based on the high emissions scenario in the 2024 Regional Summary
  • an average year in 2050 in Victoria is projected to experience around 30 heatwave days. This is compared to 20 heatwave days in the past (VCSR24)
• extreme rainfall events are projected to become more intense
  • For 2050, projections indicate ‘very heavy’ rainfall days could have 5–15% more rainfall. The upper end of the projected likely range shows increases of 20–40%. This depends on the seasons and emissions scenario (2024 Regional Summary)
• droughts in Victoria are likely to increase in duration and intensity with climate change. Although the precise nature and extent of impacts are unclear (VCSR24)
• thunderstorms in Australia are expected to increase with global warming (VCSR24).

Ben assesses the physical climate risks. To do this he considers how climate change might impact the likelihood and consequences of the harms. He considers additional controls. These are on top of the ones he planned as part of the initial design, which he based on current climate conditions. These added controls help reduce the risk rating that increases over time due to climate change.

Ben is considering several controls to minimise risks of harm from pollution and waste. This includes those from reducing risk in the premixed concrete industry.

He will consider each climate hazard. He will assess whether it is reasonably practicable to incorporate more controls to minimise the physical climate risks.

Several climate hazards can lead to increased dust generation. This includes:

• increased drought
• heatwaves and extreme heat.

To minimise this risk, Ben considers:

• installing hardstand surfaces across the entire site (rather than selected areas)
• using roofed bays (rather than 3-sided bays)
• installing fully enclosed conveyor belts and enclosing all transfer points
• adding water storage options for increased dust suppression. (e.g., using sprinkler systems to wet down material in storage bays).

Increased drought could also lead to drying of soil. This could lead to foundation damage to plant and buildings. To minimise this risk, Ben considers an additional geotechnical assessment.

More extreme and heavy rainfall events can increase pollution of surface waters. This can be due to increased site stormwater runoff and flash flooding, which can occur anywhere. Localised flooding can also lead to reduced site operation. To minimise these risks, Ben looks at:

• designing the stormwater system to allow for increased rainfall and inflow volumes. He will use the latest:
  • Australian Rainfall and Runoff guidelines
  • Melbourne Water Model for Urban Stormwater Improvement Conceptualisation (MUSIC) Modelling Guideline.
• keeping chemicals and waste chemicals:
  • in sealed containers
  • above flood levels
  • in areas designed to contain spills.
• the Liquid storage and handling guidelines. It can assist in design of the storage area surface and bunding.

Escape of dust emissions offsite could increase. This is due to the damage of buildings and other structures from more intense and frequent storms. To minimise this risk, Ben considers the following in the design:

• vulnerable structures and buildings
• installing dust extractors and collection systems. He also considers operating buildings under negative pressure where practicable.

Loss of power to the site from more intense and frequent storms could result in:

• potential air emissions escaping offsite
• pollution of surface waters
• reduced site operation.

Ben considers installing backup power as part of the design to minimise this risk. This can provide electricity to critical infrastructure.

Ben has prepared an environmental management plan (EMP). The EMP documents the risk management process for the site.

He includes the following operational controls:

• regular updating of emergency management plan and procedures. This accounts for increased risk of catastrophic equipment failure
• regular monitoring of weather and adjusting of activities as needed.
• regular updating of inspection procedures, increasing inspections on hot days. This will help prevent dust accumulation on driveways, internal roads etc.

On a regular basis, Ben:

• reviews the efficacy of his EMP especially after extreme weather events
• checks and maintains effective climate-related controls
• reviews updated climate projection data. This can help him identify if he needs any future controls.
  

They identify the following climate hazards as relevant to the location and industry:

• heatwaves and extreme temperatures
• annual rainfall
• extreme rainfall/flooding
• storm events.

The consultant sourced historical weather data from the Bureau of Meteorology (BOM) from a nearby weather station. This helped determine baseline weather data for 1986-2005. After consulting with the BOM and flood data, they found no evidence of extreme weather events near the site.

The consultant:

• used Victoria’s Future Climate Tool to assess some climate hazards
• assessed future climate under both a medium (RCP4.5) and high (SSP3-7.0) emissions scenario
• used 2030 and 2050 time horizons (as the plant has a 30-year design life).

The qualitative assessment included the following climate parameters:

• average and extreme temperatures
• average and extreme rainfall
• heatwaves including number, duration and frequency
• extreme dry conditions and duration of dry conditions.

Not all climate hazards, like floods and storms, are covered by Victoria’s Future Climate Tool. To get information on these, the consultant referenced:

• VCSR24
• factsheets
• Greater Melbourne regional summaries.

The information above was used to inform a workshop. Workshop participants included internal staff and external climate risk assessment experts. Workshop participants:

• used the climate science. This helped identify potential risks from current and future climate change. (see Implementing controls)
• assessed physical climate risks. They considered the likelihood of the climate hazards causing harm and the consequences of each harm.
• They used the same risk scales and rating description as the corporate risk register. The scales include impacts on human health and the environment
• rated risks from current and future climate change. This was for both medium and high emission scenarios for the time horizons
• assisted in identifying controls. These controls add to those planned to minimise risk from current climate conditions. Implementing these added controls will reduce the high risks to medium or low.

Mary will consider some engineering controls during the design phase. Changes to the design to incorporate future climate change will be considered, so far as reasonably practicable. Mary will also consider controls in the management and operation of the plant.

Climate hazards, potential risks and controls to minimise physical climate risk

Increased average and extreme temperatures can lead to:

• more pollution incidents. This is due to expansion and stress of plant infrastructure, pipework and fittings. This can result in cracks and leaks. Mary considers:
  • reviewing the design of plant infrastructure, pipework and fittings to handle higher temperatures.
• increased fire risk for stored flammable chemicals and waste. Mary considers:
  • reviewing the design of the ventilation and cooling system. This can account for projected increases in ambient and extreme temperatures
  • installing smoke and flame detection systems to detect any fire in the early stages
  • installing and routinely servicing fire protection equipment
  • installing a drainage system to collect firewater. This will prevent it entering the environment.
• an increase in odour from the site due to increased volatility of stored chemicals. Mary considers:
  • the potential increase in odour in the design of the ventilation system
  • a chemical stability assessment. This will help to understand how temperature and humidity changes may affect the safety or stored chemicals. It includes assessing the stability, reactivity or volatility of stored chemicals.

Increased frequency, severity and duration of extreme rainfall events and flooding. This could lead to:

• pollution of surface waters due to increased site surface water and flash flooding. Mary considers:
  • reviewing the design of the site stormwater system. This will ensure there is enough storage or treatment capacity. She uses the Australian Rainfall and Runoff Guidelines and MUSIC Modelling guideline.
  • storing hazardous chemicals in sealed containers, above any flood levels and in areas where spills can be contained. She considers liquid storage and handling guidelines. This can assist in the design of the storage area surface and bunding
  • inspecting and maintaining stormwater systems during operation.

Increase in frequency and intensity of storms can lead to:

• increased runaway emissions or chemical leaks due to damage of building structures. This can lead to heightened risk of ignition of flammable substances. Mary considers:
  • reviewing the design of vulnerable structures and buildings
  • connecting ventilation system to backup power sources. This ensures management of odours from waste
  • maintaining building integrity during operation.
• loss of power and other utilities to the site. Mary considers:
  • adding backup power and redundancy to critical systems and equipment. This ensures critical infrastructure can continue to operate in the case of power outages. Critical infrastructure includes cooling systems, heat pumps, fire protection systems and emergency lighting.

Mary will check risk controls on a regular basis once the plant is operational. This includes those related to managing physical climate risks.

• Reviewing responses to emergency events and incidents. Updating the EMP and Incident Management Plan as needed
• Conducting exercises and other scenarios from the EMP
• Updating staff training as necessary
• Revisiting her assessment and controls when:
  • the latest information becomes available
  • authoritative climate science and projections are updated.

Under a warmer and drier climate, droughts may increase risks of harm from pollution and waste such as:

• sewer spills from blockages. Increased blockages may arise from increased tree root intrusion into sewer pipes as they seek water
• poorer water quality in receiving surface waters. This is from reduced flows and dilution capacity. This can affect mixing zones and compliance with licence conditions
• unplanned discharge. This is from ground movement and pipe failure during prolonged dry conditions.

Extreme rainfall events can increase the risk of water pollution. This can happen in several ways, including when:

• intense rainfall sends excessive inflows into sewer systems or wastewater treatment plants. This can overwhelm hydraulic capacity of these systems. It can lead to release of untreated or partially treated wastewater
• wet weather flows move through treatment processes too quick or overload them. This reduces the effectiveness of the wastewater treatment. It can lead to release of partially treated or untreated wastewater
• floodwaters overflow or damage bunded or contained areas. This can allow pollutants to escape into the environment.

The company used an initial qualitative assessment to assess physical climate risks. This helped prioritise areas requiring more detailed assessment. The water company did a detailed, comprehensive and quantitative assessment of its assets that are not often replaced. The assessment:

• applied an appropriate industry standard for the likelihood and consequence. This helped inform risk ratings
• focussed on critical assets such as treatment plants and pump stations
• considered several emission scenarios and timeframes.

Climate change is already affecting water cycles. The company identified a range of future climate scenarios for its risk assessments. These represent best estimates of impacts to each system over the next 50 years. This is the timeframe for their urban water strategy.

The scenarios inform climate change adaptation actions. These can ensure effective and reliable wastewater services in the future. The company recognised it would be good to develop localised models to further explore climate projections. They used BoM information and local catchment data.

The company’s assets were not built to withstand the increasing frequency and intensity of events under a changing climate. However, incorporating climate change adaptation measures can build resilience to the expected impacts.

The company has developed an action plan. It identifies both administrative and engineering controls. The controls can address risks over a range of time periods. The company used a multi criteria analysis method to assess the effectiveness of potential controls.

The potential impact on receptors from some controls was also factored into the action plan. Such as the reuse of recycled water for irrigation considered impacts on land, groundwater, animal and human health.

The company has considered the consequences and uncertainty due to climate change. This is in line with their 50-year urban water strategy. They have identified short, medium and long-term actions. This is part of a climate change adaptation pathway approach. The business has certainty about the short-term actions.

The adaptation pathway approach provides greater flexibility. It allows for medium and long-term projects to come forward, if needed. They can consider changes in technology over time.

The business will use triggers. These will signal when decisions should be made.

Short term actions include:

• adding a climate change section to the operation, maintenance and flood management plans
• conducting an engineering feasibility study of existing systems to accommodate higher projected flows
• reviewing current tank capacity for managing short duration, increased rainfall volumes
• improving drainage capacity of sites. This can help manage increased flows and includes implementing flood/ inundation barriers.

Medium term (up to 25 years) actions may assist the company during licence renewal or EPA initiated review of their operating licence. Actions include considering and acting on:

• storage capacity constraints and upgrade requirements for wastewater treatment plants
• mechanical treatment capacity increases
• stormwater detention to adapt to higher inflows
• added wastewater treatment to cope with increased volumes and pathogen concentrations
• appropriate geotechnical stabilisation works where extreme rainfall increases soil erosion.
• investments in research to build knowledge of emerging technologies

Long term (25 to 50 years) actions include:

• investigating adaptations for infrastructure impacted by a changing climate. Such as, converting gravity flow designs to pumping stations
• planning to adopt alternative solutions to improve climate resilience such as aquifer recharge.
  

The company will ensure the assessment of physical climate risks is aligned with its related strategies and plans. For example, the Urban water strategy and Climate change adaptation action plan.

The company has also put in place:

• a system for regular checks of effectiveness of controls identified in its RMMPs
• an undertaking to review the risk assessment after a flood or extreme weather event in the region or when new risks are identified
• an action to revise models used in the assessments. This will be when new climate data is released.