Environmental Management
Commitment, Challenge and Opportunity
CH. Karnchang’s core operations, particularly its construction projects, have significant environmental impacts, including resource consumption, air and water pollution, and industrial waste management challenges.
These activities affect multiple stakeholders, including local communities around project sites, business partners, contractors, customers, and shareholders, all of whom are concerned with the company’s environmental and social sustainability. If not properly managed, these impacts could pose risks to operations, such as regulatory penalties or a decline in stakeholder confidence.
To address these challenges, CH. Karnchang has implemented environmental and sustainability policies committed to minimizing the pollution, resources, waste, and water impacts of its construction projects. This includes developing operational plans to mitigate effects on local communities and the environment while conducting ongoing impact assessments through external agencies. The company also prioritizes air pollution emission, water use and reduction, resource efficiency and responsible waste management—not only to reduce environmental harm but also to meet the growing demand for socially and environmentally responsible business practices. Furthermore, its commitment to sustainability enhances long-term business stability and strengthens stakeholder trust across all sectors.
Supporting the SDGs Goals
Goal 8:
Goal 12:
Stakeholders Directly Impacted
Goals and Performance Highlights
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Recycled waste amounted to 295 tons of carbon dioxide equivalent (tCO₂e), compared to the 2023 baseline
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Reduction of Waste and Landfilled Material Volume: Baseline Year 2023, Target Year 2024
- This represents an increase of 311 tCO₂e, or 21.65%, compared to the base year.
- This represents an increase of 66 tons of carbon dioxide equivalent compared to last year, or a 22.37% increase from the base year.
Management and Operational Approach
Environmental Management Process
CH. Karnchang’s Sustainability Policies cover environmental management, green construction practices, climate action, and biodiversity management, which focus on managing negative environmental impacts of business operations and value chain through reduction, avoidance, or efficiency improvement as demonstrated by the company’s compliance with applicable environmental regulations and standards, and issue-specific management strategies.
These principles are integrated into every stage of the construction process—from planning and project execution to waste management and post-construction sustainability. The company follows ISO 9001:2015 standards for environmental management, requiring project management teams to develop operational plans and impact mitigation strategies for local communities and the environment. Continuous quality monitoring is conducted, with third-party organizations assessing and reporting environmental impacts in compliance with project owner requirements throughout the construction phase. This ensures transparency and accuracy for all stakeholders.
Standards Compliance:
| Description | Standard |
|---|---|
| Hazardous Materials Management Plan |
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| Wastewater and Runoff Management Plan |
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| Solid Waste Management Plan |
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| Drinking Water and Water Supply Management Plan |
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| Spoil Disposal Management Plan |
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| Air pollution and Dust, Noise and Vibration Control Plan |
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| Processing Plant, Quarry, Borrow Pit Management Plan |
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| Cultural, Archaeological and Historical Heritage Management |
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The company strictly monitors and reports compliance with environmental impact mitigation measures in each project. This includes air quality control through dust suppression techniques, noise and vibration monitoring, surface water quality assessments, and aquatic ecosystem protection. Hazardous waste and debris management is carefully planned, while transportation and traffic conditions are also monitored. Additionally, CH. Karnchang actively engages with local communities to address concerns and gather feedback on potential environmental impacts.
Beyond compliance, the company fosters environmental awareness by educating employees, contractors, customers, and business partners on resource conservation, waste management, and relevant environmental regulations. This collaborative approach supports long-term, sustainable, and responsible business operations.
CH. Karnchang has also formed a committee for safety, occupational health, and environmental management. This committee keeps environmental law databases up to date and aligned with business operations, conducts scheduled internal audits to ensure regulatory compliance, and holds annual meetings to review progress, address challenges, and propose continuous improvements for sustainability initiatives.
Audit Process by Third Parties
In conducting environmental operations, CH. Karnchang typically undertakes operational and data audits covering areas such as water management, waste management, pollution control, and resource utilization at all work sites. These audits are normally performed by external auditors engaged by the company to ensure the accuracy and reliability of information prior to submitting the annual environmental report to the Office of Natural Resources and Environmental Policy and Planning (ONEP).
For the Luang Prabang Hydropower Project, environmental inspections are carried out periodically by officials from the Ministry of Natural Resources and Environment (MONRE) of the Lao PDR, as well as by the Lender Environmental and Social Advisor (LESA), who represents the project’s financing institutions. These oversight visits focus on verifying compliance with environmental and social requirements.
The project does send selected samples to accredited external laboratories in Thailand for independent testing, including:
- Soil samples from the hazardous waste landfill area, tested for chemical contamination at the Central Laboratory (Thailand) Co., Ltd., an agency under the Department of Agriculture, Ministry of Agriculture and Cooperatives.
- Water samples, including drinking water, tap water, treated wastewater, groundwater near the hazardous waste landfill, reservoir water within the project area, and Mekong River water, tested for water quality parameters at United Analyst and Engineering Consultant Co., Ltd.
- Flue gas samples from the waste incineration facility, tested for air pollutants (Stack Emission Test) at MET Co., Ltd.
These targeted laboratory analyses provide independent verification of specific environmental parameters, supporting the project’s ongoing environmental monitoring and compliance efforts.
Governance Structure
The Social Responsibility and Sustainability Committee of CH. Karnchang Public Company Limited has appointed three members to oversee the company’s sustainability initiatives. Their key responsibilities include:
- Developing and proposing social and environmental policies for approval by the Board of Directors.
- Reviewing and endorsing the company’s CSR strategies to ensure alignment with sustainability goals. Evaluating and approving the annual CSR plan and budget before submission to the Executive Committee and Board of Directors.
- Monitoring CSR activities, assessing their progress and effectiveness, and evaluating the overall impact and quality of CSR initiatives.
- Carrying out additional responsibilities as assigned by the Board of Directors.
- Promoting sustainable business development by establishing policies that foster long-term growth while maximizing benefits for all stakeholders. This is achieved through adherence to environmental, social, and governance (ESG) principles and a commitment to measurable, impactful sustainability
Water Management
Effective water management in all construction sites is a crucial factor that requires careful planning, as water is a valuable resource with significant environmental impacts. Proper management can reduce costs, improve efficiency to reduce water use, and promote environmental sustainability.
For construction-related water use, thorough planning should be conducted from the project's outset. This includes estimating water requirements at each stage, from foundation work and concrete mixing to curing and site cleaning. It is also essential to consider water sources, which may include municipal water supplies, groundwater, or local natural sources. In most cases, the company primarily relies on water provided by the Metropolitan Waterworks Authority and the Provincial Waterworks Authority. Moreover, the company also implemented water reduction actions like installing sensor-activated faucets throughout its own operations beyond construction sites, including in the Head Office.
In terms of wastewater treatment, appropriate systems must be in place. Water recycling is a key component of sustainable water management, and the company actively promotes its implementation within projects. Treated water can be repurposed for activities that do not require high water quality, such as irrigation, surface cleaning, and dust control, thereby reducing the demand for clean water. Construction activities also generate contaminated water, such as wastewater from washing concrete mixing equipment and site cleaning. To address this, the company has implemented a system to separate stormwater drainage from wastewater. Sedimentation tanks and septic tanks are used to filter contaminants before releasing water into the public drainage system. Additionally, the company emphasizes wastewater management for both construction processes and temporary sanitation facilities.
Lastly, educating construction workers on efficient water use and conservation is a priority. Training programs, clear guidelines, and regular monitoring ensure that water management practices in construction projects remain effective and sustainable.
Water Risk Assessment
CH. Karnchang has established Water Management Guidelines and a Water Risk Assessment and Management Flow to ensure responsible water use across construction projects. These frameworks support efficient water consumption, proactive identification of water-stressed areas, and mitigation of potential impacts on local communities, while promoting continuous performance improvement throughout the project lifecycle.
Stress Area Assessment
Based on the 2025 site locations reported by CH. Karnchang, a majority of the listed infrastructure projects are situated within high to extremely high-water stress areas, particularly in the central and northern regions of Thailand (e.g., Bangkok Metropolitan Area, Ayutthaya, and Chiang Rai), indicating significant competition for water resources among sectors and heightened sensitivity to drought and seasonal shortages.
In areas with high water stress, construction projects must adopt more stringent and proactive water management approaches than in low-risk regions.
Effective water governance in these zones is not only an environmental responsibility but also critical to project continuity, regulatory approval, and community trust. Projects operating in water-scarce locations must treat water management as a core component of their construction planning and risk mitigation strategy.
CH. Karnchang used Aqueduct Water Risk Atlas for analysis
| Location | Water stress status |
|---|---|
| Southern Purple Line MRT Project: Contract 1 (Tao Poon - National Library) |
High(40-80%)
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| Southern Purple Line MRT Project: Contract 2 (National Library - Phan Fa) |
High(40-80%)
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| Chulabhorn 60th Anniversary Learning and Research Center |
High(40-80%)
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| Water Transmission Tunnel Project along Kanchanaphisek Road and the Old Railway Road (Bang Mod Pumping Station - Samrong Pumping Station) |
High(40-80%)
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| Bang Ban - Bang Sai Flood Drainage Canal Project: Contract 4 |
Extremely high (80%)
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| Thonburi Wastewater Collection and Treatment System Project: Contract 1 |
High(40-80%)
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| CH. Karnchang Headquarter |
High(40-80%)
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| Double-Track Railway Project (Den Chai - Chiang Rai - Chiang Khong): Contract 3 (Chiang Rai - Chiang Khong) |
Low to High
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| Double-Track Railway Project (Den Chai - Chiang Rai - Chiang Khong): Contract 3 (Chiang Rai - Chiang Khong) |
Extremely high(80%)
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| CH. Karnchang (Lao) Company Limited - Luang Prabang Hydroelectric Power Plant |
Low
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Water Management Guidelines of CH. Karnchang
CH. Karnchang provide a structured approach to managing water use across construction projects, focusing on awareness, efficiency, risk identification, and continuous performance improvement.
- Communicate the importance of water conservation.
- Establish water use guidelines for all projects.
- Use efficient machinery and minimize washing.
- Utilize onsite storage tanks.
- Check site location using risk maps (e.g. WRI Atlas).
- Identify local water stress factors.
- Monitor water usage.
- Review and adjust water measures.
- Report to stakeholders (community, authorities).
Practical Measures
- Use concrete mixer trucks with self-washing systems to reduce the need for water rinsing by supplier.
- Reuse polymer slurry water from drilling operations by supplier.
- Install temporary rainwater harvesting systems during construction phases.
- Recirculate water in processes like concrete saw cooling, grout mixing, or hydro-demolition.
- Share water consumption and savings trends with internal leadership and external stakeholders.
Water Risk Assessment and Management Flow (Construction Projects)
CH. Karnchang has implemented Water Management Guidelines that integrate water efficiency measures, site-level risk consideration, and ongoing monitoring throughout the project lifecycle.
click to enlargeWater Monitoring and Risk Management in Construction Projects
Water accumulation within construction sites poses potential risks to structural integrity, disrupts project timelines, and leads to increased operational expenditures. To proactively mitigate these challenges, the company has implemented a comprehensive water management and drainage strategy aimed at minimizing risks at their source. A systematic approach has been established to continuously monitor and assess water levels, ensuring prompt intervention should water volumes exceed acceptable thresholds. This initiative aligns with best practices in risk mitigation, supports sustainable project management, and fulfills stakeholder expectations. The overarching principles guiding this framework are as follows:
At water-stressed sites, CH. Karnchang actively engages with its stakeholders
At water-stressed sites, CH. Karnchang actively engages with its stakeholders to ensure responsible water management. The company collaborates with contractors by implementing a monitoring process for shared water usage. This includes systematic collection and submission of water consumption data, enabling transparency and informed decision-making.
Target
To ensure effective water management within construction projects, CH. Karnchang has set a long-term water consumption reduction target for the Luang Prabang Hydropower Project. The project currently has approximately 65% project progress between 2023-2025. For the remaining 35% of project progress to be completed between 2026-2029, CH. Karnchang expects to consume 1,451 million liters of water. Thus, the company’s water consumption reduction target focuses on achieving 4% reduction in four years (2026 to project completion in 2029) from the expected water to be consumed in the Luang Prabang Hydropower Project.
Water consumption for the Luang Prabang Hydropower Project (2026 to project completion in 2029)
Tap water usage at CH. Karnchang headquarters
Performance and Results
CH. Karnchang monitors and reports water consumption, water discharge, and water reuse across its operational sites. The following tables present water-related performance data for operations in Lao PDR and Thailand during the reporting year 2025.
Water usage is categorized by key operational activities, including potable water supply for camps and site offices, concrete production, and various on-site construction activities. In addition, information on water discharge and water reuse is disclosed to provide a comprehensive overview of how water is managed throughout the construction lifecycle.
For overseas operations in Lao PDR, detailed data on water withdrawal, discharge, and reuse is presented to reflect site-level water management practices. For domestic operations in Thailand, water consumption data is reported by major construction projects and the head office. This disclosure aims to demonstrate the company’s approach to responsible water use, support the assessment of water-related risks, particularly in water-stressed areas, and provide a foundation for continuous improvement in water efficiency and management practices.
Operation in Thailand
| Water consumption within domestic projects | Unit | 2025 |
|---|---|---|
| Purple Line MRT (Contract 1) | cu.m. | 308,611 |
| Purple Line MRT (Contract 2) | cu.m. | 290,445 |
| Den Chai–Chiang Rai–Chiang Khong Railway Construction, Contract 2 | cu.m. | 36,710 |
| Den Chai–Chiang Rai–Chiang Khong Railway Construction, Contract 3 | cu.m. | 90,379 |
| Chulabhorn Hospital Learning and Research Center | cu.m. | 152 |
| Water Conveyance Tunnel, Bang Mod–Samrong Pumping Station | cu.m. | 15,322 |
| Bang Ban–Bang Sai Drainage Canal Excavation | cu.m. | 33,792 |
| Thonburi Wastewater Treatment System, Contract 1 | cu.m. | 49,936 |
| CH. Karnchang Head Office | cu.m. | 25,521 |
Operations in Loas
Water usage data of the operations site in Loas
| Water usage by activity | Unit | 2025 | % Consumption |
|---|---|---|---|
| Used for producing tap water and drinking water for the camp and site office | cu.m. | 1,309,907.63 | 71.49% |
| Used for concrete production | cu.m. | 388,131.90 | 21.18% |
| Used for various on-site activities | cu.m. | 134,306.00 | 7.33% |
| Total | 1,832,345.53 | 100% | |
Water discharge data from the operations site in Loas
| Water usage by activity | Unit | 2025 | % Consumption |
|---|---|---|---|
| Used for producing tap water and drinking water for the camp and site office | cu.m. | 1,047,926.102 | 80% |
| Used for concrete production | cu.m. | 77,626.38 | 20% |
| Used for various on-site activities | cu.m. | 107,444.8 | 80% |
| Total | 1,232,997.282 | 100% | |
Water reuse data of the operations site in Loas
| Water usage by activity | Unit | 2025 |
|---|---|---|
| Water reused from excess water from RO Process | Unit | 20,129.558 |
| Water to spray the road | Unit | 41,277 |
| Total | Unit | 61,406.558 |
Waste Management
The Luang Prabang Hydropower Project recognizes the importance of effective waste management in its operations, including leftover materials from construction, renovation, and demolition activities.
As the number of employees relocating to the project site and the local project staff increases, the amount of waste generated also increases. Without proper management in compliance with environmental regulations, this waste could have a significant impact on the environment and surrounding communities. Poor waste management can not only affect the landscape but also lead to soil and water contamination and pose safety risks to nearby residents. To address this, the company prioritizes a comprehensive waste management process, from initial planning to project completion. Waste is first sorted into two main categories: construction waste and community waste. Further classification is carried out to ensure proper disposal, as follows:
carried out to ensure proper disposal
- Non-hazardous, non-recyclable, non-combustible waste
- Non-hazardous, non-recyclable, combustible waste
- Non-hazardous organic waste, such as food scraps and vegetable waste
- Non-hazardous, recyclable, or reusable waste
- Hazardous waste, including engine oil, lubricants, grease, solvents, and batteries
- Hazardous infectious waste
Additionally, recyclable and reusable materials are sorted to minimize the amount of waste requiring disposal. Any remaining waste is sent to municipal authorities for proper processing.
CH. Karnchang has implemented waste management policies across all projects to ensure that waste handling in construction projects meets legal standards and best practices. This includes tracking of the types, quantities, and weights of waste generated from construction activities—such as soil, sand, and materials from construction or demolition. Waste is also segregated by type and managed accordingly, including recyclable materials, organic waste for composting, general and combustible waste for landfill or incineration, and hazardous waste for off-site disposal. All data is compiled and summarized monthly.
The company has implemented waste management policies across all projects to ensure that waste handling in CH. Karnchang construction projects meets legal standards and best practices. This includes tracking the types, quantities, and weights of waste generated from construction activities—such as soil, sand, and materials from construction or demolition. The company also evaluates efficiency and addresses related issues by regularly inspecting construction sites for leftover waste and debris, with weekly progress checks conducted throughout the construction phase. Furthermore, employees are encouraged to recognize the importance of proper waste separation, supporting sustainable waste management efforts.
Incorporating Resource Efficiency into Construction Design
Sustainable construction requires careful planning to minimize resource consumption from the design stage. Several strategies can help achieve this goal:
- Efficient structural design starts with choosing an appropriate system, such as a post-tensioned structure, which allows for a thinner slab, reducing the use of concrete and rebar. Additionally, optimizing column spacing can help minimize the number of foundations and columns, improving overall efficiency.
- Using environmentally friendly alternative materials, such as fly ash to partially replace cement, not only reduces cement consumption but also enhances the quality of concrete.
- The use of technology in structural design and analysis enables precise simulation and evaluation of material usage, reducing errors and minimizing material waste during construction. Additionally, modern structural analysis software enhances the design process by optimizing material efficiency.
Construction methods designed for both building and dismantling should prioritize the use of precast systems, which help minimize on-site material waste and allow components to be reused when a building is demolished. Alternatively, implementing a Design for Deconstruction (DfD) approach enables materials to be repurposed in the future. To further reduce waste, designers should consider the standard sizes of commercially available materials and align their designs accordingly. This reduces excess material from cutting and leftover scraps. For example, column span lengths should match the standard dimensions of structural steel, and wall heights should be designed to fit available sheet materials.
The selection and design of construction materials should consider lifespan and maintenance. Choosing durable materials with a long service life and minimal maintenance needs helps reduce long-term material replacement. For example, using rust-resistant materials for steel structures in areas prone to corrosion during concrete pouring.
However, all operations must adhere to safety principles and relevant design standards. Proper evaluation and testing are required to ensure that material reduction does not compromise the structural integrity.
Target
To exceed legal waste management requirements, CH. Karnchang has set a long-term waste reduction target for the Luang Prabang Hydropower Project. The project currently has approximately 65% project progress between 2023-2025. For the remaining 35% of project progress to be completed between 2026-2029, CH. Karnchang expects to generate 4,135 tonnes of waste. Thus, the waste reduction target focuses on achieving 4% reduction in four years (2026 to project completion in 2029) from the expected waste to be generated in the Luang Prabang Hydropower Project.
In addition, the project commits to maintain a recycling rate of 20% the same period of 2026-2029. This goal promotes continuous improvement in waste segregation and recycling efficiency, supporting broader sustainability objectives.
Waste generation for the Luang Prabang Hydropower Project (2026 to project completion in 2029)
Waste recycling (% of total waste)
Loss Rate of Rebar no more than 4% per year
Performance and Results
In 2025, the waste management program achieved significant environmental impact by reducing greenhouse gas emissions through two key activities: recycling and composting. Recycling efforts alone contributed to a reduction of approximately 722 tons (21.65%), while composting organic waste accounted for an additional 762 tons. Combined, these initiatives prevented the release of 868 tons CO₂e into the atmosphere, underscoring the program’s effectiveness in promoting sustainable practices and mitigating climate change.
Air Pollution Management
During construction, total suspended particulates (TSP) and fine particulate matter (PM10) are key air pollutants that must be properly managed to minimize environmental and community impacts.
CH. Karnchang has implemented effective dust control measures to mitigate the effects of construction, renovation, repair, and demolition activities, which often release airborne dust. These measures help maintain air quality in nearby areas and reduce potential health risks for workers and surrounding communities.
Measures for controlling and reducing particulate matter emissions from construction activities
Work with the project owner to ensure compliance with relevant laws, regulations, and best practices for dust control in construction, including the National Environmental Quality Act of 1992, Bangkok city regulations, and the Pollution Control Department’s guidelines on managing construction dust.
Installing a water spray system at the construction site to control dust.
Lightly spray water over areas with exposed soil, as well as soil and sand piles, to reduce airborne dust.
Clean the vehicle and its wheels to remove any dirt, mud, or sand before taking it outside the construction site.
Limit vehicle speed in construction zones to minimize airborne dust.
Establish guidelines for dust control in construction, identify air quality monitoring points, and strictly adhere to plans and procedures in accordance with government-set standards.
CH. Karnchang continuously monitors and assesses air quality by measuring the 24-hour average of total suspended particulates (TSP) and particulate matter smaller than 10 microns (PM10) using a High Volume Air Sampler. Additionally, levels of nitrogen dioxide (NO₂) and sulfur dioxide (SO₂) are monitored to ensure air quality remains within regulatory standards. Additionally, CH. Karnchang has implemented a strategy to manage construction-related dust issues by setting up air quality monitoring points throughout the project site. The company also defines the project boundary, work plans, and operational procedures in compliance with government-mandated environmental standards.
Additionally, CH. Karnchang has implemented a strategy to manage construction-related dust issues by setting up air quality monitoring points throughout the project site. The company also defines the project boundary,
work plans, and operational procedures in compliance with government-mandated environmental standards.
Target
CH. Karnchang has set a goal to reduce air pollution caused by the organization's operations by setting the following goals:
- The average concentration of airborne particulate matter should not exceed 0.33 mg/m3
- with PM10 levels maintained below 0.12 mg/m3
