Sustainability Report 2025

Stepping Up When Others Step Away

2025 Sustainability Report

Diversified Energy 2025 Sustainability Report 2

Table of Contents

OVERVIEW

Diversified at a Glance 3 A Message from

Our CEO 4

Our Corporate Culture 5

Sustainability

Approach 6

From the Office

of Sustainability 7

Sustainability Framework 8

Financial Sustainability 10

Operational Sustainability 11

Stakeholder Engagement 12

Issues that Matter the Most 13

Sustainability: 2025

Progress & 2026 Targets 14

PLANET

Protecting Our Environment 16

Environmental

Management System 17

Greenhouse Gas

Emissions 18

Air Quality 26

Energy Efficiency

& Renewables 26

Well Retirement 27

Water & Waste

Management 29

Spills 32

Biodiversity 34

PEOPLE

Supporting Our Employees 36

Safety...No Compromises 37

Talent Acquisition

& Management 43

Employee Training

& Development 45

Engagement & Culture 47

Health & Well-Being 48

Serving Our

Communities 50

State-by-State

Economic Impact 51

Community Engagement 53

Community Support 54

PRINCIPLES

Governing Our

Actions 56

Governance Framework 57

Compliance & Ethics 60

Risk Management 61

Political & Corporate

Advocacy 62

Information Systems 63

Cybersecurity 64

APPENDIX

Glossary 66

About This Report 67

Performance Data Table 68

Emissions Assurance 73

GRI Content Index 75

SASB Content Index 79

Additional Resources 84

Contact Us 84

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3

NET PRODUCTION

PROVED RESERVES

1,086

MMcfepd

6,082

Bcfe

PRODUCTION MIX: GAS & NGL

88%

TOTAL REVENUE

PRODUCTION MIX: UNCONVENTIONAL

57%

TOTAL EMPLOYEES

$1.6

Billion

1,987

in 14 states

WESTERN ANADARKO/ OKLAHOMA

APPALACHIA

PERMIAN

HAYNESVILLE/ COTTON VALLEY

Core basins

Processing facilities

Non-op development

‌Diversified at a Glance

Diversified Energy Company (Diversified, DEC or the Company) is a leading publicly traded U.S. onshore energy producer focused on acquiring, operating, and optimizing mature natural gas and liquids

assets, supported by vertically integrated midstream, marketing, and well-retirement operations. From our Birmingham, Alabama headquarters, the Company serves a wide range of customers across 14 states of operation, including energy marketers, LNG export facilities, local municipalities and utilities, other producers, and industrial and retail end users.

With a de-risked business model, Diversified is a proven consolidator that enhances the operational and environmental performance of acquired assets throughout their lifecycle and responsibly retires them at end of life. Recognized by rating agencies and industry organizations for our sustainability leadership, the Company's stewardship-driven approach

supports responsible energy production, reliable free cash flow generation, and long-term economic and environmental value creation.

Diversified is honored to have received a 2026 Gold Stevie Award for Best Small Energy Company for its

commitment to operating with excellence and driving sustained value for stakeholders.

Diversified Energy 2025 Sustainability Report Overview Planet People Principles Appendix 4

‌A Message from Our CEO

2025 stands as a testament to Diversified's strategic vision and execution capabilities, evidenced in record-setting financial and operational performance. It was a year of profound transformation that further solidified our position as a leading energy producer committed to Stepping Up when others step away from the challenge of owning and operating established assets."

Consistent, Proven Strategy

Since our 2017 IPO, Diversified has executed more than 30 acquisitions exceeding $5 billion, transforming the scale and longevity of our asset portfolio. In 2025, we successfully closed and integrated our largest acquisition to date - the $1.275 billion acquisition of Maverick Natural Resources (Maverick) -demonstrating the strength of our repeatable, well-defined growth strategy and integration playbook.

Alongside Maverick, the 2025 addition of Canvas Energy (Canvas) and assets from Summit Natural Resources (Summit) significantly expanded our operational footprint, enhanced operational leverage, and further validated our ability to unlock value at scale. These integrations deepen our confidence in the durability of our strategy and our capacity

to capture future growth opportunities while maintaining financial discipline.

Relentless Execution Driving Value

In 2025, Diversified delivered record production, driving a doubling of revenue, EBITDA and Free Cash Flow versus 2024 and marking the strongest financial performances in the Company's history. We also announced an innovative, first-of-its-kind partnership with the State of West Virginia to establish a dedicated assurance well plugging fund, reinforcing our leadership in responsible stewardship.

Beyond core operations, we enhanced corporate value and acquisition returns by monetizing land sales on assets acquired at zero cost. We also continued to invest financially and physically in the communities where we live and work, executed through our growing community affairs programs.

These record-setting results demonstrate the strength of our proven strategy: disciplined, de-risked growth enabled by a vertically integrated operating model and an unwavering focus on execution. Our ability to

consistently acquire, integrate, optimize and responsibly operate long-life assets enables us to generate durable cash flow while creating additional revenue opportunities. Responsible operations are inseparable from our business model and remain central to our pursuit of sustainable, long-term value for all stakeholders.

Staying the Course

For Diversified, 'sustainability' is the foundation of how we operate and grow responsibly. Time and again we have proven this approach, one that is solidly anchored in four core principles: value creation and protection, operational excellence, responsible environmental action, and human and community well-being.

Diversified has always operated under a One DEC culture, grounded in innovation, collaboration, accountability, and shared purpose. With our significant 2025 acquisitions, we are advancing toward a bigger and better One DEC by unifying superior assets and ongoing relentless execution to fully realize the value of our expanded portfolio. As we approach and celebrate nearly 25 years as a successful and growing energy company, we owe special thanks to our employees who made it happen and to our investors and business partners for their continued support.

This report reflects our commitment, today and into the future, to sustained performance, operational excellence, and responsible execution, and we welcome your feedback and inquiries.

Robert R. "Rusty" Hutson, Jr.

Founder and Chief Executive Officer

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‌Our Corporate Culture

At Diversified, we are a leader because of the talent, skill, and tenacity of every member of our team.

What we do every day is driven by who we are and what we represent. Our Core Values, Daily Priorities, and Winning Language aren't just concepts. Rather, they are the foundation of our corporate culture - guiding how we work, communicate, and achieve success together.

In turn, our daily demonstration of these fundamentals drives meaningful impact by creating a system of trust, accountability, and success by ensuring we are all moving forward in alignment, with purpose and excellence.

Read more about our corporate culture initiatives in Engagement & Culture herein.

OUR CORE VALUES

Our Core Values define who we are and how we engage with one another, our communities, and business partners.

They reflect our responsibility as stewards of stakeholder interests and help us earn and sustain their trust. By living these values, we reach our highest potential as individuals and contributors to the Company and stay grounded in the standards that guide our actions and define Diversified.

OUR DAILY PRIORITIES

Our four guiding daily priorities are the underlying key to making our acquire-and-operate business model a proven success. We embrace these guidelines and challenge our employees to make them a priority in their daily work as they reflect our foremost commitment to safety as well as our commitment to focused operational results, sustainability and environmental stewardship.

OUR WINNING LANGUAGE

Our winning language is a shared framework that aligns our intent with action and serves as the cultural connection between who we are (our Core Values) and where we focus each day (our Daily Priorities). Embedded in our communications and actions across Diversified, this common language guides how we work, support one another, and consistently execute our individual and corporate goals.

WHO WE ARE WHERE WE FOCUS HOW WE ENGAGE

Diversified Energy 2025 Sustainability Report Overview Planet People Principles Appendix 6

‌Sustainability Approach

1. From the Office of Sustainability

2. Sustainability Framework

1. Financial Sustainability

2. Operational Sustainability

3. Stakeholder Engagement

4. Issues that Matter the Most

5. Sustainability: 2025 Progress

& 2026 Targets

Diversified Energy 2025 Sustainability Report Overview Planet People Principles Appendix 7

‌From the Office of Sustainability

Stepping Up means doing the hard work-integrating people, systems, and standards-so that process improvement remains our top priority. As we take on new assets and accompanying performance opportunities through our acquisitive business model, the core tenets of our sustainability journey remain continuous consolidated improvement, accountability, and transparency."

Teresa B. Odom Senior Vice President of Sustainability

Diversified plays an essential role in responsibly meeting growing energy demand. In 2025, undeterred by a continually evolving political and energy landscape, we remained focused on a balanced, practical approach grounded in efficiency, reliability, and best practice. Sustainability, viewed through the lens of long-term value protection and creation, provides the framework that makes this approach possible by guiding daily decisions, strengthening governance, and reinforcing accountability across our operations.

2025 was also a year of significant integration, including our largest acquisition to date, as we unified people, systems, and standards under our One DEC framework. From a sustainability performance perspective, we recognize that integration can create short-term complexity and drive non-linear

year-over-year changes as inventories and operating practices are recalibrated, but we view this as

an opportunity and a catalyst for stronger future performance.

This dynamic is most evident in safety. While we advanced several important initiatives, we did not meet our 2025 personal and driver safety objectives, with TRIR increasing to 1.65 (incidents per 200,000 work hours) and PMVA to 0.55 (per million miles driven). We are addressing this directly. As performance began to fall short during the year, we immediately began rebuilding our entire safety program with renewed focus, including refreshing our safety management system in alignment with ANSI/ ASSP Z10, strengthening leadership accountability through a new Safety Leadership Committee, and collaborating across legacy and newly acquired teams to integrate best practices, reinforce work controls, and deepen employee participation.

A similar integration effect appears in our emissions results. While we executed multiple initiatives to drive pre-acquisition reductions, Scope 1 and 2 emissions increased year over year due to portfolio growth.

Even so, we strengthened the foundation for durable reductions by consolidating our emissions inventory and

calculations within a single carbon accounting system of record, expanding voluntary LDAR coverage across our enlarged footprint to achieve a 99% no-leak rate, earning OGMP 2.0 Gold Standard Reporting recognition in just our fourth year of participation, and eliminating or converting natural gas-driven equipment. Cross-functional task forces, including for pneumatics and methane slip, are actively identifying scalable, often innovative mitigation solutions.

Looking ahead, we are building one unified culture and operating system designed to deliver safer operations, lower emissions, and stronger execution. Thank you for your interest in Diversified's sustainability journey. We appreciate your continued engagement as we keep raising the bar for ourselves and the industry while embracing our leadership role in Stepping Up to the challenge of delivering sustained value from operating existing assets.

SUSTAINABILITY HIGHLIGHTS

GHG SCOPE 1 & 2 YOY CHANGE

(9%)

Pre-acquisition

OGMP 2.0 CERTIFICATION

Gold

Reporting

WATER RECYCLE RATE

92%

SPILL INTENSITY YOY CHANGE

(10%)

PERSONAL SAFETY PROGRAM

100%

Overhaul Launched

COMMUNITY OUTREACH

$1.8 Million

See details herein for more information on these achievements.

Diversified Energy 2025 Sustainability Report Overview Planet People Principles Appendix 8

‌Sustainability Framework

Our comprehensive sustainability framework focuses on creating and preserving stakeholder value across every stage of our strategy and operations.

Grounded in six core pillars of risk management, asset integrity, employee safety, environmental protection, emissions reduction, and community engagement, this framework ensures that sustainability considerations guide how we acquire and manage assets, make daily decisions, and support our people and communities.

Our acquisition-driven business model expands our portfolio and geographic reach while enabling us to apply our proven, disciplined operating methods to enhance asset performance, efficiency, and environmental outcomes. By improving reliability, optimizing production, and reducing operating costs and emissions, this approach strengthens both operational and financial sustainability,

thus extending asset life, stabilizing cash flows,

and supporting long-term value for our stakeholders. Together, these outcomes reinforce our commitment to operational excellence and responsible, sustainable growth.

Our Differentiated Stewardship Model

Stewardship is not just an ideal. For Diversified, it is the foundation of how we operate. By combining rigorous investment due diligence, our Smarter Asset Management operating

approach, and systematic, responsible retirement of end-of-life assets, we demonstrate that operational excellence and sustainable growth are complementary and mutually attainable goals. Together, these practices define our differentiated approach to stewardship and underpin our commitment to delivering lasting, sustainable value throughout an asset's lifecycle.

A key component of our daily stewardship operating model is optimized decision-making enabled by real-time data. Information flows continuously from the field to the corporate office, thus equipping operational teams and leadership with visibility to identify risks, enhance efficiency, and pursue continuous improvement. This connected system, in

turn, supports strong governance while reinforcing a culture of accountability in which sustainability is a shared responsibility.

SUSTAINABILITY COMMITMENT

We are committed to addressing key environmental issues for our PLANET and likewise relevant social issues for the PEOPLE we engage across our operations, and doing so with a constant focus on the values and PRINCIPLES under which we were founded and continue to operate.

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Stewardship through the Asset Lifecycle

From pre-acquisition due diligence to safe, systematic retirement, we employ a comprehensive, lifecycle asset management approach that prioritizes sustainability and operational excellence at every stage.

PRE-ACQUISITION DILIGENCE

SMARTER ASSET MANAGEMENT

ASSET RETIREMENT

Our acquisition-driven growth strategy is supported by a rigorous, multidisciplinary due-diligence process designed to ensure strategic fit, long-term value creation, and risk mitigation. Beyond financial performance, this process evaluates environmental performance, safety and workforce integration, and legal and compliance readiness. By embedding these factors into investment decisions, we strengthen integration planning, mitigate risk, and reinforce our commitment to operational integrity, stakeholder value, and ethical governance.

Our Smarter Asset Management (SAM) approach serves as the cornerstone of how we integrate sustainability into our operations. This data-driven process combines advanced monitoring technologies, predictive maintenance, and operational analytics to reduce fugitive emissions, improve production reliability, and enhance cost efficiency. As both a business imperative and sustainability initiative, SAM exemplifies how responsible stewardship and strong economic performance align to drive long-term value.

Through our Next LVL Energy subsidiary, we safely and permanently retire end of life assets as part of our Safe and Systematic Asset Retirement program, which applies standardized, data-driven processes and strong oversight to meet or exceed regulatory requirements and support our environmental goals.

This approach underscores our belief that responsible retirement is essential to responsible ownership, and Next LVL extends this stewardship by retiring third party, orphaned, and abandoned wells.

Excellence in Energy - Upstream

ESG/Sustainability Report of the Year

Best Sustainability Reporting (small to mid-cap)

In recognition of our demonstrated actions and disclosure transparency, in 2025 we received the following Finalist (short-list) award recognitions for our 2024 actions and related Sustainability Report, Winning Through Collaboration:

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‌Financial Sustainability

Financial sustainability is the cornerstone that supports our ability to deliver on our operational, environmental, and social commitments. It is driven by a proven business strategy and strong vertical integration that positions Diversified to safely and efficiently operate established assets, deliver reliable and affordable energy, and retire wells responsibly-creating lasting value for shareholders, communities, and the environment."

Brad Gray President and Chief Financial Officer (CFO)

STRENGTH THAT DRIVES RESPONSIBLE OPERATIONS

More than a single action or metric, financial sustainability at Diversified is the engine that powers our ability to operate responsibly and deliver long-term value. Every employee plays a role in enabling, supporting, and delivering financial results that drive our success.

Financial sustainability starts with a consistently demonstrated accretive growth model underpinned by innovative acquisition financing and forward-looking protections that support stability, enable efficient operations, and promote investments in emissions-reduction technologies and asset retirement, while simultaneously supporting community engagement. This sustainability is delivered through a vertical integration model that allows control along the entire value chain - from acquisition to retirement

- and thus increases efficiencies, promotes improved operational decision-making, and minimizes our third-party costs while supporting third-party revenue generation.

Accretive Growth

Financial Innovation

Built-In Resilience

We have demonstrated repeated success in acquiring and integrating attractively-valued assets, gaining operational efficiencies, and driving durable value through our de-risked business model. As Diversified progresses, so too has our ability to deliver consistent growth in production, cash flow, and asset scale while utilizing an information technology (IT) and operational technology (OT) approach to drive daily decision-making and subsequent investments. Our financial strength and operational capabilities position us as a

leading steward of long-life assets with the proven ability to acquire, optimize, and retire those assets while delivering reliable energy and continued financial strength.

A cornerstone of our financial strategy is our market-leading, investment-grade Asset-Backed Securities (ABS) program, which provides low-cost, long-term financing aligned with asset cash flows. Built-in amortization supports steady deleveraging and disciplined repayment while preserving capital to support environmental initiatives such as methane mitigation and plugging. We further protect cash flows through a robust hedging strategy that mitigates commodity price volatility. Our 38,000+ mile midstream system provides access to more than 260 sales points, enabling broad market reach, end-use optionality, and third-party fee generation. Our in-house marketing team enhances revenue expansion through, in part, gas storage field optimization and arbitrage opportunities, and alternative energy credit sales.

Our disciplined approach to capital management, combined with deep operational expertise, ensures we have the resources and capabilities to responsibly operate assets across our entire

footprint. By maintaining a strong balance sheet and leverage structure suited to our stable, cash-generative assets, we fund programs that reduce methane emissions and apply proven approaches for well integrity, monitoring, and maintenance practices. This financial and operational foundation creates a mutually reinforcing cycle: sustainability initiatives protect and optimize production, while strong operational performance strengthens our financial position and capacity to fund continued investment in responsible operations, environmental risk mitigation, and well retirement.

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‌Operational Sustainability

We are integrating and co-creating best-in-class practices in field operations, safety, environmental performance, and capital discipline across our enlarged asset portfolio. By deploying these standards consistently among all operations and locations, we are building a stronger, unified "One DEC 2.0" company well positioned to deliver long-term value for all stakeholders."

Rick Gideon

EVP & Chief Operating Officer (COO)

OPERATIONAL EXCELLENCE THAT DRIVES PROVEN PERFORMANCE

In 2025, Diversified closed three strategic acquisitions that strengthened scale and margins through operational synergies and introduced new revenue opportunities, such as non-operated development opportunities and the capture and conversion of third-party coal mine methane emissions into salable environmental credits.

Joining Diversified from the Maverick acquisition as the Company's new Chief Operating Officer, Rick Gideon led the day-to-day operations integration of these acquisitions into Diversified's portfolio. He was supported in this role by our Chief Human Resource Officer and Chief Information Officer who provided co-management of the employee and technology aspects, respectively, of this comprehensive integration process. Throughout the process, our Board monitored the integration's strategic goals and achievements to protect shareholder value and employee interests. As part of our proven integration playbook, various stakeholders were consulted and included, as appropriate, throughout the process.

Rick shares his thoughts on the integration process and how a new and improved One DEC framework is building a more resilient, efficient, and sustainable Diversified.

Is there a core value that guides your leadership and how did you apply it during the integration?

I have two core values-communication and collaboration. During the integration, I focused on bringing together two strong operational cultures by working closely with teams across legacy and acquired assets, learning from one another, and empowering employees to take ownership-building a stronger, unified organization rather than imposing a singular approach. The intent should always be that we can be better together by utilizing new and better ideas to continuously improve.

What do operational excellence and winning look like as "One DEC 2.0"?

Operational excellence as One DEC 2.0 means winning together-operationally and financially-by working as a unified team. It's field, technical, and leadership groups aligned and collaborating around shared data, ownership, and relentless execution. We aim to provide the right tools to the right people so that they can make the right decisions at the right times. When our people and systems grow together, empowered and supported, we consistently deliver results and build a strong culture.

Safety is vital to the success of our operations. How do you ensure that safety remains the Company's top daily priority?

Safety is our foundational value and number one daily priority. It is "how" we work. I stay actively engaged with field and support teams, reinforce best practices, and ensure consistent processes across all assets. Through

strong oversight, frontline empowerment, and continuous improvement, we create shared ownership-proactively identifying risks to better protect our people and maintain safe,

reliable operations.

Emissions reduction is a key component of our environmental stewardship and long-term sustainability. Where do you see opportunities to reduce emissions while improving operational efficiency?

We see strong opportunities to reduce emissions while improving efficiency by applying our proven roadmap across all assets. By measuring and prioritizing emissions with advanced detection, targeting leaks and equipment upgrades, and using high-quality operational data, we reduce our environmental footprint while enhancing performance and scalability.

In what ways does the non-operated development opportunity from the Maverick acquisition complement Diversified's core operating model?

Diversified's non-operated development opportunity complements our operating model by providing

low-risk, capital-efficient development with consistent operational results. Partnering with a proven operator diversifies our portfolio and enhances financial flexibility which support reinvestment in safety, sustainability, and other initiatives that drive

long-term stakeholder value.

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‌Stakeholder Engagement

Strong, transparent stakeholder relationships are essential to responsible and sustainable operations. We actively engage internal and external stakeholders to identify priority topics that guide our sustainability approach, ensuring the insights we receive shape how we operate, improve, and deliver long-term value. Our engagement emphasizes clear communication and proactive dialogue, maintaining open feedback channels that strengthen trust, enhance responsiveness, and ensure alignment with stakeholders' environmental, social, and governance priorities. Rooted in stewardship and long-term partnership, our stakeholder engagement spans employees, investors, communities, governments, customers, and business partners, and includes a range of communication methods designed to encourage collaboration and

continuous improvement.

FEEDBACK CHANNELS

2025 By The Numbers

How We Engage

• Code of Business Conduct & Ethics

• DEConnection intranet

• Compliance hotline & website

• C-suite town halls & field visits

• Performance

  management system

• Career training & development

• Engagement surveys

• Safety meetings

• Health & wellness programs

• Annual shareholder meeting

• Annual lenders meeting

• Analyst & portfolio manager engagements

• Investor presentations & conferences

• Quarterly earnings releases & calls

• Annual financial & sustainability reports

• Socio-Economic & Biodiversity policies

• Community giving program

• Internship & scholarship programs

• Employee volunteerism

• Matching gift program

• Local hiring

• Tax revenue & GDP contributions

• First responder & public safety events

• Advocacy & policy development

• Industry association leadership & participation

• Tax Policy

• Annual statement of payments to governments

• Regulatory engagement, audits & compliance

• Field & facility tours

• States' partner in orphan/abandoned well retirement programs

• Dedicated owner relations access

• Marketing events & conferences

• Call Before You Dig

  program

• Pipeline awareness programs

• Domestic taps program

• In-field engagement with operations team

• Business Partners Policy

• Online compliance website

• Contractor risk

  management tools & programs

• Competitive bidding

  program

• Contract management

Applicable to all stakeholders: corporate Call Center, company website, digital and multimedia campaigns, active social media presence, and corporate press releases, presentations and other public materials.

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‌Issues that Matter the Most

In 2023, Diversified conducted a comprehensive, multi-stakeholder materiality assessment aligned with

leading sustainability frameworks and our Enterprise Risk Management (ERM) process, evaluating and prioritizing 29 environmental, social, and governance topics through internal and external interviews, stakeholder outreach, and peer benchmarking to inform our sustainability strategy, strengthen risk oversight, and guide corporate initiatives.

This assessment confirms that our sustainability efforts are deeply connected to our business strategy- managing environmental impact, engaging people and communities, and upholding strong operating principles. We continue to proactively engage stakeholders to track emerging issues and ensure our priorities remain aligned with their expectations. In line with best practice, we are conducting a new assessment in 2026 to maintain a clear,

forward-looking view of the sustainability issues most likely to influence company performance and stakeholder value.

The Assessment Process

SELECT MATERIAL TOPICS UTILIZING:

• prior assessments

• stakeholder outreach

• peer benchmarking exercises

LAUNCH AND COMPILE ASSESSMENT SURVEY

ANALYZE MATERIAL ISSUES AND CREATE STRATEGIES/METRICS

Planet People Principles

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‌Sustainability: 2025 Progress & 2026 Targets

PLANET

Supported by data-driven management and a strong culture of stewardship, the tables below highlight our commitment to measurable performance, transparent disclosure, and meaningful progress toward certain environmental and social goals. While some 2025 targets set at year-end 2024 were not achieved as originally expected, we view these challenges as valuable opportunities for continued learning and improvement. Invigorated by a now expanded asset portfolio and exceptional team, we've wasted no time in 2026 prioritizing and advancing the work needed to achieve our new sustainability targets and further strengthen our performance.

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Diversified Energy 2025 Sustainability Report Overview Planet People Principles Appendix 16

‌Protecting Our Environment

17 Environmental Management System

18 Greenhouse Gas Emissions

26 Air Quality

26 Energy Efficiency & Renewables

27 Well Retirement

29 Water & Waste Management

32 Spills

34 Biodiversity

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‌Environmental Management System

Diversified is committed to balancing growing energy demands with responsible resource management. Through a comprehensive Environmental Management System (EMS) and strengthened roadmap to reducing our environmental footprint, we are passionate about environmental stewardship achieved through proactive execution and innovative solutions.

The cornerstone of our environmental sustainability culture is our SAM operational approach which focuses on optimizing asset performance and reducing environmental impact. Our OneDEC safety culture, combined with intentional programs, protocols, and proven practices, contributes to a comprehensive and standardized approach to our responsible resource management.

Our EMS guides the responsible management of our upstream, midstream, and well retirement activities. Diversified prioritizes regulatory compliance and implements a field-based approach to enhance our environmental performance, as exemplified in our key environmental commitments.

OUR ENVIRONMENTAL COMMITMENTS

Eliminate Fugitive Emissions

Reduce Total Emissions

Decrease Freshwater Consumption

Reduce Waste

Protect Biodiversity

Increase Energy Efficiency

A central element of our environmental footprint management strategy is our integrated asset connectivity. We operate through a centralized, all-cloud, wireless technology stack that enables real-time data and analytics on automated assets. Partnered with our exceptional field management capabilities, this system allows us to seamlessly

incorporate information streams from acquired assets into our existing EMS.

Diversified's goal is to deliver timely and actionable data to implement effective changes. Our comprehensive EMS is supported by 24/7 Integrated Operations and Gas Control centers for certain upstream and midstream assets, respectively. This enhanced system aims to prevent environmental incidents and allow for rapid response when needed. Our EMS is also improved by utilizing the Iconic Air carbon accounting platform to integrate comprehensive emissions data, allowing us to calculate, visualize, and report emissions from all assets within the portfolio as well as prioritize future emission reduction efforts.

Our EMS approach directly connects to Diversified's key environmental commitments. The following narrative highlights our many environmental stewardship programs, including specific practices and initiatives to manage and continuously improve our environmental performance.

For more information on our EMS approach, please see our separate Environmental, Health and Safety and Climate policies on our website.

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‌Greenhouse Gas Emissions

With a focus on the acquisition and operation of established assets, Diversified views effective greenhouse gas (GHG) management as both an environmental responsibility and an operational imperative.

Our 'Every Molecule Counts' approach emphasizes asset integrity, disciplined maintenance, and preventive controls designed to avoid methane losses. By keeping natural gas molecules in the pipe and delivered to a sales

meter, we reduce emissions while improving efficiency, reliability, and asset value. Even amid evolving energy demand and regulatory uncertainty, efficiency remains a constant, and avoiding fugitive emissions is simply good business, for both Diversified and the environment.

Grounded in accurate measurement, consistent management practices, continuous improvement, and transparency in reporting, Diversified's GHG strategy is underpinned by a SAM program that empowers our teams to collaborate, innovate, and take ownership of asset performance from acquisition to retirement.

These practices reinforce responsible growth aligned with environmental stewardship and sustainability.

In 2025, Diversified continued advancing efforts to reduce emissions across an expanded portfolio while also contributing to broader industry progress.

Our environmental team remained actively engaged in industry forums, peer-to-peer working groups, and methane advisory efforts, sharing practical insights and best practices for emissions reductions. As a leader in this space, we recognize the importance of translating our experience into actionable guidance that supports operating efficiency and emissions reductions across the industry, including for smaller operators or other reporting jurisdictions.

Tackling Emissions Reductions

As our portfolio evolves through acquisitions, we apply a disciplined framework to understand emissions sources, ensure transparency, and deliver meaningful environmental and operational outcomes.

Assess the source(s) of emissions

Establish workflows, from the field to the system of record

Develop emissions profile by equipment type

Define and prioritize the reduction strategy

DIVERSIFIED'S PRIORITIES

• Fugitive leaks (facilities & pipelines)

• Pneumatic devices and pumps

• Engines

• Other (compressors, tanks, dehydrators, liquids unloading)

Implement reductions and process changes

Utilize fit-for-purpose technology to identify and measure emissions

Continually improve accuracy to inform decisions and prioritize next steps

By maintaining consistent standards and oversight across our asset base, Diversified has built a scalable platform that supports emissions reduction while enabling safe, reliable, and efficient operations.

Independent third-party validation reinforces the strength of this framework, as evidenced in our fourth consecutive Oil & Gas Methane Partnership 2.0 (OGMP 2.0) recognition and achievement in 2025 of Gold Standard Reporting for in-scope assets, the program's highest designation,

This recognition reflects multi-year investments in advanced measurement and detection technologies, universal leak detection and repair (LDAR) programs, and the elimination or conversion of natural gas-driven equipment. Measurement-based methane disclosure also positions Diversified to supply the Responsibly Sourced Gas valued by utilities and LNG buyers and aligns our reporting with emerging international methane standards such as the European Union Methane Emissions Regulation (MER) and the South Korea-Japan CLEAN initiative.

Diversified Energy 2025 Sustainability Report Overview Planet People Principles Appendix 19

Our emissions-reduction strategy is built on a largely circular, data-driven model that enables continuous improvement. Data from multiple systems informs targeted actions, those actions are enabled and verified through a suite of technologies, and the resulting insights flow back into our data systems to guide the next cycle of decisions. This repeatable process strengthens accuracy, efficiency, and accountability across our operations.

DATA: A SINGLE SOURCE OF TRUTH

We utilize IBM's Maximo Asset Management system to capture total inventory on each 'cut of dirt' in our portfolio - approximately 302,000 assets spanning upstream and midstream operations. The equipment data is integrated into Iconic Air, our carbon accounting system of record, ensuring seamless, comprehensive capture of emissions sources across the portfolio.

In 2025, our "Air Force" team completed validation and full migration to Iconic Air after running parallel records with our legacy spreadsheet system. As our portfolio expanded, the spreadsheet approach became increasingly complex and more conducive to data integrity issues. Transitioning to Iconic Air eliminated more than 30 extensive workbooks and established instead a single, validated system with streamlined data entry, robust quality checks,

multi-level calculations from reporting area to individual piece of equipment, and detailed audit trails.

BY THE NUMBERS

Diversified's Air Force created records for

73,000 locations &

245,000 inventory assets

and completed approximately

739,000 calculations

related to emissions across 17 reporting basins and multiple EPA calculation frameworks within Iconic Air to support year-end 2025 emissions reporting.

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TECHNOLOGY:

DETECT, MEASURE, VERIFY

We deploy a fit-for-purpose suite of complementary methane detection and measurement technologies across our upstream and midstream operations, including handheld devices, optical gas imaging (OGI) cameras, continuous monitoring systems, and aerial surveillance. Together, these technologies enhance emissions accuracy, enable effective detection and verification across diverse asset types and operating environments, and accelerate mitigation efforts. This integrated approach strengthens emissions performance and reporting confidence while supporting the expanded use of direct measurement under EPA 40 CFR Part 98, Subpart W, and the OGMP framework.

Aerial LiDAR Surveillance

Through our ongoing partnership with Bridger Photonics (Bridger), periodic Light Detection and Ranging (LiDAR) surveys identify fugitive emissions with equipment-level precision and are approved for NSPS OOOOa & OOOOb regulatory compliance. Aerial detections are relayed to field teams for targeted field verification and repair, reducing reliance on labor-intensive ground surveys and focusing resources on the highest-priority reduction opportunities. Deployed across both Appalachian and Central regions, this voluntary program has delivered measurable efficiency and cost benefits and will continue in 2026.

Handheld Laser OGI

BY THE NUMBERS

During 2025, Bridger surveyed nearly

100%

of legacy assets and

98%

of newly acquired Central assets, covering

~9,400 miles

of pipeline and

~14,300 facilities

across six states

We continue to leverage Xplorobot's EPA-approved handheld OGI technology, which integrates directly with our data systems to identify assets, pinpoint leaks, and generate work orders. In 2025, we expanded this pilot program by purchasing two devices and certifying more than a dozen employees on its application and use. The technology supports OGMP Level 4 quantification and Subpart W reporting for newly acquired assets and shows strong potential for broader regional deployment.

Remote Monitoring

Through our Integrated Operations Centers (IOCs), Diversified monitors production and key operating parameters across approximately 75% of automated upstream and midstream automated assets in the Central region, with a clear path to 100% coverage through ongoing system integration initiatives. IOC operators identify abnormal conditions in real time, enabling immediate remote intervention where possible or prompt field response. This capability is complemented by facility-level continuous monitoring devices, including Qube and Project Canary units deployed on select assets, which provide 24/7 methane monitoring.

Diversified and Xplorobot were recognized for their innovative partnership with a Methane Mitigation Excellence Award.

In parallel, our centralized Gas Control Center operates 24/7 oversight of more than 1,700 miles of regulated midstream assets across six states, with the ability to remotely manage gas flows. Together, these real-time remote monitoring systems play a critical role in proactively preventing unintended environmental impacts while supporting safe,

reliable operations.

SUSTAINED IMPROVEMENT

Working together, these data systems and technologies enable faster detection, targeted repairs, improved reporting confidence, and measurable operational efficiencies. The insights generated are fed back into our systems of record, strengthening future decision-making and reinforcing a continuous cycle of emissions identification and reduction.

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Our employees' expertise and collaboration have been instrumental to the success of our emissions reduction strategy. Fully supported by senior leadership and strengthened through investments in technology, our teams continue to embody an innovative spirit that challenges the status quo and delivers measurable results across our operations.

PNEUMATICS TASK FORCE

Diversified's company-wide, cross-functional Pneumatics Task Force, established in 2024 and active throughout 2025, advanced targeted strategies to reduce emissions from natural gas-powered pneumatic controllers and pumps.

METHANE SLIP TASK FORCE

Methane emissions from natural gas engines, commonly referred to as methane slip, are a recognized industry challenge, particularly for

lean-burn engines. In 2025, we established a Methane Slip Task Force to proactively address this issue through targeted monitoring, optimization, and mitigation strategies. The team advanced several complementary, data-driven initiatives including (i)SCADA-based analytics to identify anomalous engine operating conditions and support SCADA alarm system integrations; (ii)engine-tuning trials focused on ignition timing and intake air to reduce emissions from under-loaded lean-burn units; and (iii)evaluation of crankcase closed-vent recycling to eliminate crankcase emissions while reducing fuel use and oil consumption.

Together, these efforts are informing 2026 priorities related to engine selection, system integration, and the scaling of methane-mitigation actions that support both emissions reductions and long-term engine performance and reliability.

Pneumatics: Retrofits and Eliminations

In the Western Anadarko Basin, we piloted an emission reduction project across nearly 100 company-owned compressor skids encompassing some 550 pneumatic devices. The project captures natural gas exhaust from the devices (such as interstage scrubber dump valves) using tubing and routes it back into the compressor's engine fuel lines for on-site fuel use. Following the project's success, we shared this approach with compressor leasing vendors to encourage broader adoption across leased equipment.

In Appalachia, our Midstream Operations team developed and implemented a power take-off system that uses compressor engine power to drive an integrated air compressor, supplying instrument air to pneumatic devices at sites without grid access. Adapted from mobile equipment applications and tailored for stationary compressors, the system provides a reliable

on-site power source while eliminating the need for standalone air compressors, generators,

or solar-battery systems as well as the ongoing maintenance for each. Each installation enables the conversion of approximately 10-15 natural gas-driven pneumatic devices to instrument air.

The Pneumatics Task Force eliminated or converted more than 1,470 pneumatic devices in 2025, exceeding our objective by over 23%.

Coordinated efforts across our operating regions included equipment retrofits, device

eliminations using compressed air, instrument gas recycling, and evaluation of alternative technologies. The success of these collective efforts helped inform our 2026 capital planning and actions.

These scalable, fit-for-purpose, innovative solutions now serve as models for additional pneumatic system conversions across the Company's expanded operations.

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REPORTING METHODOLOGY

Our 2025 GHG inventory uses GHGRP24, which allows expanded calculation options, including direct measurement and operator-specific factor development, and represents a meaningful advancement over prior methodologies. Given that the current Administration has delayed the 2025 reporting deadline and proposed suspending reporting obligations through 2034, we believe applying the established 2024 framework provides the most defensible and consistent basis for our emissions inventory. We have not restated prior year emissions to reflect 2025 methodology changes, as it introduces new source categories and calculation approaches for which the underlying historical input data is not readily available.

Importantly, while our reported emissions

trends may not be linear - fluctuating largely due

production which contributed to lower atmospheric emissions from storage tanks. These reductions were offset by a net 1% increase in methane emissions driven by improvements in reporting methodologies for blowdowns and improved field level tracking of liquids unloading (accounting changes).

With no significant change in year-over-year net methane emissions, methane intensity increased from

0.7 MT CO2e per million cubic feet equivalent (MMcfe) of production to 0.8 MT CO2e/MMcfe primarily as a function of natural production declines of the base business. We believe this intensity rate continues to reflect the success of our emissions playbook that is focused on equipment optimization and improved reporting, and more broadly reflects the value of our circular, data-driven emissions reduction strategy.

IMPACT OF ACQUISITIONS

As expected, significant portfolio growth in 2025 contributed to higher year end absolute emissions.

2025 TOTAL EMISSIONS

Inclusive of acquisitions, absolute Scopes 1 and 2 GHG emissions increased to 2,614 thousand MT CO2e.

Representing 26% of total GHG, methane increased year over year to 680 thousand MT CO2e, driving a 2025 year-end overall methane intensity increase to 1.0 MT CO2e/ MMcfe. Nitrous oxide (N2O) remains an immaterial component (<0.1%) of our overall GHG emissions. Please refer to the Assurance Statement in the Appendix for additional information on 2025 reported emissions.

SCOPES 1 & 2 GHG EMISSIONS

(thousand MT CO2e)

1,646

1,502

(144)

1,113 2,614

to acquisitions, methodology updates, and evolving reporting standards - our focus remains on delivering real, underlying emissions

Total Scopes 1 and 2 GHG emissions from these acquisitions added 1,113 thousand MT CO₂e, largely attributable to increased engine and pneumatic device

2024

Year End

2025

Activity (net)

2025

before Acquisitions

2025

Acquisitions

2025

Year End

reductions through disciplined execution and continuous improvement as noted below.

PRE-ACQUISITION EMISSIONS

For assets owned at December 31, 2024 (base assets), absolute Scopes 1 and 2 GHG emissions declined 9% in 2025 to 1,502 thousand metric tons (MT) of carbon dioxide equivalent (CO2e) driven primarily by eliminations and rightsizing of combustion equipment, which directly contributed to a nearly 35% reduction in metered

inventories and, new to Diversified's asset portfolio,

natural gas flaring in the Permian Basin where third-party midstream operators can influence the timing and volume of reportable flaring activity.

These acquisitions also carry a higher methane intensity than our base business and, because of the closing timing of the acquisitions during the year, reported emissions reflect only a partial period of incorporating Diversified's reduction initiatives. For example, we were able to combine our already planned use of Bridger's LiDAR technology to survey

• CO2 ■ Methane

SCOPE 1 METHANE INTENSITY

(MT CO2e/MMcfe)

0.7

0.1

0.8

0.2 1.0

fuel emissions.

Absolute methane emissions from base assets increased immaterially year over year. Real reductions to methane were largely attributable

nearly 100% of the now expanded Central Region

assets in 2025, with the exception of the Canvas acquisition which closed late in the year. As with all acquisitions, we develop a comprehensive emissions inventory and multi-year reduction plans upon

2024

Year End

2025

Activity (net) and Production Rebase

2025

before Acquisitions

2025

Acquisitions

2025

Year End

to the aforementioned combustion eliminations,

ongoing pneumatic device and pump conversions or eliminations, and naturally declining oil

integration to deliver meaningful absolute reductions in future reporting periods and are already executing on this plan.

Totals may not sum due to rounding. Minimal N2O emissions are included above though not visible at this scale.

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Amid rapid change in the global energy sector, Diversified remains focused on executing a deliberate, balanced strategy anchored in operational excellence and energy security. We focus on identifying and advancing opportunities that complement and extend our proven business model while capitalizing on our core operational strengths.

COAL MINE METHANE

Environmental Credits Provide Cash Flow Boost

COAL PRODUCTION

METHANE EMISSION

CAPTURE / ABATEMENT

CREDIT GENERATION

We leverage our expertise and financial strength to selectively diversify into adjacent energy initiatives that are strategically aligned with our core capabilities and capable of delivering sustainable, attractive returns.

With the completion of the $42 million strategic, portfolio-enhancing acquisition of Summit in 2025, the Company added natural gas production assets and related midstream infrastructure within its existing southern Appalachian operations. This acquisition strengthened Diversified's ability to capture production economics through regional scale while opening the door to utilize its operational expertise in adjacent energy markets, including

low-carbon transportation fuels and Alternative Energy Credits (AECs) generated from the capture of coal mine methane (CMM).

Diversified continues to advance initiatives to capture CMM vented from third-party operations, converting methane emissions into revenue-generating sales of natural gas, AECs, and, increasingly, low-carbon transportation fuels. These initiatives not only create salable environmental attributes but also provide strategic flexibility to retain and utilize those attributes internally as aligned with the Company's own emissions-reduction objectives.

The capture and abatement of CMM delivers multiple co-benefits: it reduces atmospheric methane emissions, enhances mine safety by eliminating physical risk to workers, supplies electricity generated from the abated methane, and supports the production of low-carbon transportation fuels.

Collectively, these outcomes demonstrate a mutually beneficial model that aligns operational reliability with shared decarbonization and sustainability goals.

Diversified is uniquely positioned to benefit from the

U.S. Department of the Treasury's final rules under Section 45Z of the Inflation Reduction Act, which enable the production of low-emission transportation fuels and the generation of Clean Fuel Production Credits (CFPCs). CMM qualifies for CFPCs due to its inherent environmental benefits associated with emissions abatement, creating a compelling opportunity to expand and monetize Diversified's environmental credit portfolio.

Looking ahead, the Company is pursuing the expansion of its CMM operations across multiple markets while continuing to evaluate opportunities to repurpose legacy wells for alternative and low-carbon uses. These efforts include converting wells otherwise slated for permanent closure into value-generating assets, such as those supporting geothermal energy generation or carbon credit creation.

As new opportunities and technologies emerge, potential projects like these are systematically evaluated through a carbon lens supported by our Iconic Air data warehouse and carbon accounting tool, which helps us prioritize investments that deliver the greatest impact financially, operationally, and environmentally. This diligent approach enables us to methodically evaluate and, where prudent, participate in new avenues of revenue and operational growth.

Diversified Energy 2025 Sustainability Report Overview Planet People Principles Appendix 24

TCFD AT A GLANCE

As part of our commitment to transparent reporting, we disclose our climate risks, opportunities, and resilience annually in line with the Task Force on Climate-related Financial Disclosures (TCFD) framework (with the exception of Scope 3 emissions). The following is a summary of our climate-related disclosures, with complete details available in our separately published Climate Risk and Resilience Report which can be found on

our website.

CLIMATE RESILIENCE: KEY TAKEAWAYS

Governance

Climate accountability occurs at every level of the Company, beginning with a dedicated Sustainability & Safety Committee leading Board oversight of corporate risk appetite and potential climate risk impacts to growth strategy. Executive and senior leadership develop and oversee climate-related sustainability initiatives with accountability through KPIs, while business unit advisory working groups execute approved climate strategies.

Strategy

Our pragmatic decarbonization strategy remains

Diversified's approach to climate, specifically emissions reductions, positions the Company well for supporting increasingly demanded energy security in the U.S. and abroad. Achievement of OGMP 2.0's highest Gold Standard Reporting recognition reaffirms our commitment to responsibly produced natural gas, a commodity sought by utilities and LNG exporters and required for alignment with the EU's MER.

A refreshed and enhanced scenario analysis confirms that climate-related physical and transition risks are not expected to have a material financial impact on Diversified's business. Portfolio resilience is supported by asset diversification, emergency preparedness, and operational flexibility, with scenario modeling showing positive free cash flow across multiple time horizons under a wide range of transition pathways.

Climate-related governance is embedded from the Boardroom to field operations, supporting active oversight, aligned incentives, and clear accountability across the organization. This framework supports disciplined, methane-focused emissions management through strategic acquisitive growth, cost-effective technologies, asset optimization, and ongoing target refinement following portfolio changes.

A pragmatic, methane-focused operating model aligns climate stewardship with energy security, disciplined capital allocation, and continuous improvement across emissions, water management, and asset lifecycle performance. Operational execution drives corporate resilience, emissions reductions, regulatory readiness, and durable value creation across the asset lifecycle.

practical and focused, prioritizing near-term methane reductions while advancing broader lower-carbon initiatives through SAM operations, expanded and enhanced leak detection, and fit-for-purpose technologies. Climate-related risks and opportunities are financially prioritized, with portfolio analysis demonstrating resilience across transition and physical risks, including under multiple Net

Zero scenarios.

Risk Management

Climate risk is embedded within our ERM framework under the oversight of the Board's Audit & Risk Committee. Aligned with the Board's risk appetite, risks are identified, assessed, and monitored using structured scorecards. The Senior Vice President of Sustainability directly oversees climate risk controls and regularly reports progress to management and the Board.

Metrics & Targets

We track key metrics to assess climate-related risks, opportunities, and environmental performance, with results disclosed annually. Working toward harmonization with emerging standards such as IFRS S2, our reporting highlights GHG emissions and water management. Executive and senior leaders' variable compensation is partially linked to achieving environmental and sustainability targets.

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Building on the success of our 2025 initiatives, we see multiple, clear opportunities to expand targeted emissions reduction projects. We will look to our established Pneumatics and Methane Slip task forces to continue advancing their respectively identified

opportunities for emissions reductions, whether through technology applications, physical eliminations or retrofits, or in-house innovative solutions. We will also continue malfunction and LDAR surveys, with a particular focus on pneumatics to reduce reliance on default factors by confirming actual leak/no-leak conditions in the field. These efforts will be supported by a fit-for-purpose technology portfolio of emissions detection and measurement devices, such as handheld tools and aerial surveillance, that is integrated with

high-quality data to prioritize repairs and plan future LDAR campaigns.

In parallel, we will continue working with midstream partners to reduce natural gas flaring where appropriate, particularly in situations where force majeure events can drive extended downtime, while recognizing that new third-party pipelines and gas plants under construction may improve basin takeaway capacity over time. Across our mature asset base and future acquisitions, Diversified will continue to lead with our proven SAM operating practices-optimizing assets, eliminating or converting emissions sources, and rightsizing equipment-to deliver measurable methane mitigation and continuous improvement in emissions performance.

As the regulatory landscape continues to evolve, Diversified will closely monitor changes that affect GHG reporting requirements and industry expectations. Even as recent EPA actions indicate that annual GHG reporting may no longer be required, we plan to continue reporting emissions until further notice because we believe that consistent disclosure supports transparency, strengthens stakeholder confidence, and improves comparability. Grounded in our SAM operating best practices and our focus on delivering maximum natural gas production to sales, we will remain disciplined in using accurate measurement, repeatable processes, and prudent capital allocation to guide decisions and deliver durable emissions reductions.

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‌Air Quality

Our commitment to environmental stewardship includes sustained compliance with both state and federal air quality regulations. Our proactive and varied approaches to reduce methane emissions, such as through LDAR or natural gas pneumatic device eliminations or conversions to compressed air, have the co-benefit of reducing VOCs.

2025 AIR QUALITY METRICS

35,892 MT

Nitrogen Oxide (NOx, excluding N2O)

27,536 MT

Carbon Monoxide (CO)

125 MT

Sulfur Oxide (SOx)

7,625 MT

Volatile Organic Compounds (VOC)

211 MT

Particulate Matter (PM Total)

As new assets are integrated into our portfolio, Diversified conducts systematic environmental compliance reviews to identify legacy risks, address compliance gaps, and expose opportunities for improvement. This process includes implementing our voluntary LDAR program and incorporating acquired assets into broader emissions-reduction initiatives, such as pneumatic device upgrades and deployment of monitoring and new technologies.

In 2025, we completed seven voluntary air-quality self-audits, reinforcing our proactive approach to integration and environmental compliance across the portfolio.

A key part of our success is a cross-functional Air Force team who meets monthly to

align on evolving air regulations, evaluate emerging monitoring technologies, and advance emission-reduction initiatives including mitigation, continuous monitoring, and LDAR improvements. These sessions also strengthen permitting, compliance, and reporting rigor to

ensure consistent progress toward our air quality and GHG goals.

In 2025, we constructively engaged with six state agencies as they developed state implementation plans required under Emission Guidelines

(EG) OOOOc, the federal program directing states to establish methane and air emissions standards for existing oil and gas operations.

Our engagements included hosting site visits and sharing data from our voluntary leak detection program and pneumatic device inventories. We also provided technical input focused on practical implementation considerations, particularly for marginal well operators who are often small businesses, to support informed and balanced regulatory development.

Energy Efficiency & Renewables

We continues to advance energy-efficiency initiatives and incorporate renewable energy solutions where practical to support our core gas and oil operations.

While Diversified remains focused on gas and oil production, we also actively pursue

low-carbon and energy-efficient solutions that reduce emissions and enhance operational performance.

Our multi-year program to eliminate natural

gas-driven pneumatic devices continued in 2025, with conversions to compressed air, electric, and renewable-powered alternatives where feasible. Where applicable, we also deploy electric valves in grid-connected areas and use solar panels or small wind turbines to support remote operations. While efficiency gains in 2025 were more than offset by increases from acquisitions, we sourced approximately 535 million kWh of electricity from low-carbon sources-natural gas, nuclear,

and renewables-representing more than 80% of our total electricity purchases of 663 million kWh.

LOW-CARBON ELECTRICITY SOURCES

44%

Natural Gas

8%

Nuclear

28%

Renewables

Together, these efforts support the sustainability, efficiency, and long-term resilience of our operations.

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‌Well Retirement

Well retirement is a core component of Diversified's lifecycle management approach and a central pillar of our

environmental stewardship. Retiring wells responsibly reduces long-term liabilities and supports broader sustainability goals, reinforcing the importance of a disciplined retirement program.

As one of the region's most active well-retirement teams, our Next LVL Energy (NLE) wholly-owned subsidiary maintains full-service, in-house capabilities that reduce reliance on third-party contractors, enhance operational efficiency,

and generate third-party revenue across our Appalachian footprint.

Our retirement strategy focuses on three key tenets:

We maintain dedicated, in-house plugging crews to provide consistency, operational flexibility, and

Our teams emphasize materials recycling and reuse, soil remediation, habitat restoration, and proper disposal methods to minimize environmental impact.

Together, these elements strengthen our commitment to responsible well retirement and support our broader goal of managing assets safely, efficiently, and sustainably from acquisition through end of life.

Our 2025 plugging efforts focused on improving operational efficiency and increasing the number of retirements through more robust planning and

optimized resource utilization. At the same time, we expanded the number of rigs and teams during the year to support our commitment to increasing total annual wells retired for our own account and that of third parties.

WELL RETIREMENTS

As a result, the Company retired a record 388 Diversified-owned wells in 2025, including 235 wells in Appalachia to exceed our long-standing annual commitments with the states and achieve for the fourth consecutive year our near-term goal to plug at least 200 owned wells. This accomplishment

was achieved in large part through NLE's addition in 2025 of two internal rigs and operating teams, bringing our owned pole rig count to 17 (14 active) at year end with accompanying operating teams.

Contracted third-party well retirements contributed another 98 plugs, bringing our total 2025 Diversified retirement activity to 486 wells. Of these 98 third-party wells, 75 wells were part of

six different orphan well packages awarded to NLE from the states of West Virginia and Ohio as well as the U.S. Department of Interior. The remaining wells in these awarded packages will be plugged in 2026.

For our 2025 Appalachian well retirements, NLE managed the replanting of ~6,700 pounds of native

greater control over safety, quality, and scheduling.

Even so, we continue our use of third-party partner rigs to retain the ability to scale their use as needed.

We use a proactive, hybrid leak-detection approach, conducting pre- and post-plugging scans, to

2023

2024

2025

300

404

486

and pollinator-friendly seed mix and the restoration of >176 acres in returning these locations to their natural state. Additionally, we installed bird and bat boxes to promote habitats for native species. Further, we recycled salvaged material where appropriate as part of

effectuate accurate emissions measurement and tracking and to promote environmental protections.

• Appalachia ■ Central/Other ■ Third Party

our waste management program.

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The Common Sense Solution to Well Retirement

On the heels of a record year in well retirements, we are anticipating significant increases in retirements of

In 2025, Diversified and the State of West Virginia established the Mountain State Plugging Fund, a first-of-its-kind long-term agreement providing financial assurance for the safe retirement of all Diversified-owned wells in the State. Developed collaboratively, this agreement strengthens environmental protection for West Virginia while enhancing operational certainty for Diversified.

Under the terms of this agreement, Diversified will fund $70 million across a 20-year period and will retire at least 1,500 wells during this same period, with a goal to retire 250 wells per year thereafter.

Secured and guaranteed by an independent assurance provider, the fund will grow to $650 million of financial protection for West Virginia as the third-party beneficiary to ensure the wells are properly retired.

This pioneering approach offers a scalable model for both Diversified and the industry as a whole to address legacy infrastructure challenges, and demonstrates how innovative, public-private collaboration can balance environmental responsibility with operational flexibility across the energy sector.

our owned wells in 2026 and beyond, owing in part to regulatory changes in our Central region, changes in certain States' definition of inactive wells, and the fulfillment of commitments entered into by Maverick prior to its acquisition by Diversified. These changes could increase Diversified's total owned retirements by more than 50% to some 600 wells per year

by 2026.

We remain optimistic that in 2026 and beyond States will continue to pursue the permanent closure of their expansive orphaned well inventories, and we intend to pursue these activities. Therefore, assuming third-party retirements of an estimated 100 wells per year for the States and other third-parties, total well retirements under Diversified's direct or managed activities could exceed 700 wells. We are actively positioning ourselves to achieve this increase through early 2026 acquisitions of additional retirement equipment and teams and expanded utilization of third-party partnerships.

At the same time, new regulations in West Virginia for plugging "modern wells" create an opportunity to reduce well retirement costs by as much as 20% and reduce the total time to plug a well by one to two days. These changes create potential significant benefits for our West Virginia retirement activities and present additional support for Diversified to seek similar changes in our other states of operation.

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‌Water & Waste Management

Recognizing water as a finite and critical resource, Diversified manages water withdrawal, consumption, reuse, and disposal to protect the availability and quality of water resources in the areas where we operate. We annually evaluate water stress conditions within our footprint to inform risk-based, responsible water management decisions. Because water consumption and produced water management activities are inextricably linked within our operations, our water stewardship approach prioritizes both by seeking to reduce freshwater use, manage produced water in an environmentally responsible manner, and advance recycling and reuse practices where feasible.

WATER MANAGEMENT STRATEGY

Our water withdrawal and consumption are related to domestic use, asset retirement, well

operations such as well maintenance and enhanced recovery efforts, and, to a lesser extent, hydraulic stimulation. As expected, acquisitions during the year can significantly influence water withdrawal and consumption patterns, as observed in 2025; however, we systematically evaluate water availability, infrastructure constraints, disposal capacity, and water reuse opportunities as part

of the integration of newly acquired assets.

Water Consumption

Water use in our asset retirement activities is primarily associated with cementing operations required to permanently plug wells. As we increase the number of operated wells per year that we expect to retire, water consumption will correspondingly increase. Our use of fresh or produced (salt/brine) water in our retirement activities is dictated by the States' respective regulatory requirements.

As part of our SAM operating approach, we also use water in certain well maintenance and treatment activities to improve optimization and production. This year, Diversified's Maverick acquisition significantly increased well operation water volumes in regard to both withdrawals and consumption, where acquired assets in the Rockies, Permian Basin, and Florida produce significant amounts of water from the wellbores. However, as highlighted herein, we are able to reuse and recycle a large portion of that volume in our waterflood and enhanced recovery efforts as well as return it directly to the hydrological cycle through permitted discharge. In doing so,

these recycling efforts limit the need to consume fresh water.

As a production-focused company that grows primarily through the acquisition and optimization of established assets, the Company does not consume the large volumes of water typically associated with hydraulic stimulation activities. The limited stimulation-related water consumption reported in 2025 reflects our role as contract operator for a small number of natural gas wells drilled by

third-party developers in West Virginia for their own use. As operator of record, we included the water used to stimulate these nine wells within our reported water consumption for the year.

Water Sharing Agreements

As part of our produced water management strategy, we deploy digital monitoring and performance systems to strengthen data quality, enhance accountability, and reduce disposal costs. Our digital ticketing platforms enable real-time verification, improved contractor oversight, and accurate tracking of water volumes across our operations.

We leverage risk-analysis intelligence to guide capital allocation decisions and address emerging constraints such as third-party transportation and disposal capacity, underscoring the strategic value of collaborative produced water sharing agreements and recycling efforts. In 2025, our Appalachian and Central regions achieved notable progress where more than 41% of produced water volumes were recycled or reused as compared to less than 1.5%

in 2024.

Collaborating with more than 30 other operators in Pennsylvania, Ohio, and West Virginia, Diversified continues to expand the use of water sharing agreements in Appalachia as a core component of our water management strategy. These agreements allow operators to exchange, reuse, and recycle produced water, minimizing broader reliance on freshwater sources. In 2025, we entered into five new water sharing agreements across the basin and recorded a 4% increase in shared water volumes.

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2025 WATER PERFORMANCE

Our approach to water use and management in 2025 continued to balance operational efficiency,

environmental protection, and tailored strategies with an increased emphasis on reuse and recycling through best practices and operational advancements. Acquisitions during the year contributed to noteworthy changes in our water management practices and performance, driven largely by the nature of Maverick's assets with

TOTAL WATER CONSUMPTION INTENSITY

(Water Consumed (Bbl) / Gross Production (Boe))

2024 0.039

2025

• Fresh Water ■ Produced Water

additional influences of increased well retirement activities and higher employee counts.

Year-over-year freshwater consumption increased approximately 80% to six million barrels (MMBbl) primarily related to increases in asset retirement activity, employee count impacting domestic use, and hydraulic stimulation volumes in Diversified's legacy

MANAGED PRODUCED WATER

99%

2024

2025

MMBbl

27.8

BY THE NUMBERS

92% water

recycle rate

0% consumption

in High/Extremely High water stress areas1

94% consumption

in Low water stress areas1

58% produced water

recycled/beneficially discharged

865kdisposal truckloads

avoided with recycle/discharge

>37 MBbl

stormwater discharged to hydrological cycle

178.8

operations. These increases contributed to a 2025 freshwater consumption intensity of 0.053 Bbl/Boe as compared to 0.038 Bbl/Boe in 2024.

With the addition of Maverick's assets in the year,

• Injected

  for Disposal

• Recycled/ Reused

• Discharged by Permit

total recycled produced water volumes increased substantially in 2025 to 74.1 MMBbl. These produced volumes were reused in waterflood and enhanced recovery operations, contributing to a total water consumption intensity of 0.708 Bbl/Boe in 2025 as compared to 0.039 Bbl/Boe in 2024.

Responsible wastewater management remains central to our stewardship efforts, and even more so now with the addition of Maverick's assets that increased total managed produced water volumes nearly 6.5x from 27.8 MMBbl in 2024 to 178.8 MMBbl in 2025.

Virtually 100% of the Company's produced water in 2024 was injected for disposal, negatively impacting disposal costs, spill incidents, and roadway traffic and emissions from hauling. Following the integration of Maverick's assets, produced water disposal by injection declined to 42%, with recycle/reuse and permit discharge volumes combining for the remaining 58% of total produced water management.

WYOMING SURFACE WATER DISCHARGE

In Wyoming, through a regulated produced water discharge program managed under NPDES permit, Diversified safely returned more than 29 MMBbl of treated water to the hydrological cycle

for beneficial use in support of local community, agricultural, and environmental needs. This program demonstrates our ability to apply fit-for-purpose water management solutions that comply with regulatory requirements while enhancing water availability in the regions where we operate.

PROCESSING PLANT WASTEWATER MANAGEMENT

Diversified's processing plant in Florida achieves 100% reuse of produced wastewater. This produced water is blended with minimal volumes of fresh water for re-injection down hole to support reservoir pressure maintenance and increase hydrocarbon recovery.

1 Percent of gross operated production measured at the county level, applying World Resources Institute's Aqueduct Water Risk Atlas and assuming oil & gas industry weighting

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Our teams are dedicated to continuous improvement in resource stewardship across all assets. While

we are harmonizing waste management practices throughout our expanding operational regions, we are also integrating digital tracking technologies to enhance reporting capabilities and identifying additional waste reduction opportunities.

Recycling Electronics

With a workforce of nearly 2,000 employees, we are able to extend the life of our electronic technology through responsible reuse. In 2025, we donated 100 refurbished iPads to Cornerstone Christian School in Alabama

to support elementary STEM learning, along with 20 laptops to update the school's computer lab for high school research and writing. These donations reflect a core tenet of our Community Giving program focused on advancing STEM proficiency among youth.

Many assume that as a private school we have ample resources for 21st-century learning, but we intentionally keep tuition low so more students can attend. As

a result, our budget is tight and limits our access to technology. I am grateful that God moves the hearts of companies like Diversified to support small organizations like ours."

Margaret Pickett

Principal

Diversified's waste management philosophy is rooted in responsible handling, reduction, and reuse of materials across our operations. With our strategic focus on optimizing existing assets rather than extensive drilling, we generate modest waste volumes in our operations which are predominantly classified as non-hazardous materials.

Building on prior initiatives, in 2025 we updated our Appalachia waste management plan and began integrating newly acquired assets into their respective regional plans. These efforts support the development of a comprehensive, unified waste management framework that applies consistent protocols across our operating regions while remaining tailored to local activities, infrastructure, and available resources.

Across the Central and Appalachia regions, Diversified teams actively reuse and repurpose tubular materials recovered during well retirement for internal operations or sale to third parties.

When reuse is not feasible, certain metal materials are sold to processors for recycling into new steel

products. This approach reduces waste, improves cost efficiency, generates incremental revenue, and supports environmental sustainability.

Our waste reduction efforts continue to uphold stringent regulatory requirements while embracing circular economy principles through material repurposing and community-focused reuse opportunities. In 2025, our Central teams maintained productive partnerships with local organizations

to repurpose decommissioned equipment for agricultural applications and community projects. Meanwhile, our Appalachian operations expanded specialized recycling programs targeting batteries, lubricants, and waste oil recovery.

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‌Spills

Spill prevention is an integral part of Diversified's environmental management and a core element of our commitment to asset integrity. Avoiding liquid releases is fundamental to safe, compliant, and sustainable energy operations. Proactive measures to prevent unintended fluid releases protect personnel, safeguard ecosystems, and reduce operational disruptions. This focus strengthens operational reliability and upholds Diversified's reputation for safety

and environmental stewardship.

Our spill strategy centers on proactive prevention, early detection, and continuous improvement.

We seek to implement the right equipment, tools, and techniques tailored to each site's needs, ensuring risks are uniquely addressed yet with a collective consistency that supports the Company's environmental stewardship aims.

We continue to embed a comprehensive

spill-prevention framework across our operational footprint, including through the systematic integration of best practice Spill Prevention, Control, and Countermeasure (SPCC) plans into acquired assets to maintain full state and federal compliance. As Diversified grows, our approach remains grounded in operational excellence

and transparency, thereby protecting our assets while safeguarding the environments in which we operate.

This year, we continued to advance spill reduction initiatives that reinforce both operational resilience and environmental protection. By expanding

the integration of prevention tools and response mechanisms across our growing operations, we strengthened our ability to prevent spills, respond more quickly when incidents occur, and further protect the environments in which we operate.

EARLY DETECTION

We actively promote the use of our Near Miss reporting system not only for personal safety but also environmental protection such as for identifying and mitigating potential spills. This reporting process, supported by increased physical site inspections, serves as an important early warning system for

spill prevention.

Technology also plays a central role in this approach, with expanded deployment of SCADA systems and field-level telemetry, where applicable, providing continuous visibility into fluid levels, pressures, and flow rates. This real-time monitoring enables rapid identification of abnormalities and faster response, including remote shutdowns or prompt field dispatch.

SPILL TASK FORCE

Made up of representatives from EHS, Operations, and Engineering, this task force meets monthly

to conduct root cause analyses, evaluate incident trends, and share cross-regional lessons. These reviews ensure that any reported Near Miss or actual event translates into actionable improvements across our footprint.

PREVENTATIVE MAINTENANCE

As part of our preventive maintenance program, we use enhanced failure analysis to identify potential leak sources, such as corrosion or mechanical fatigue, and enable proactive, targeted mitigation. To further reduce spill risk and potential environmental impacts, we continue to strengthen secondary containment measures, including expanded use of improved liner systems.

Planet

Diversified Energy 2025 Sustainability Report Overview People Principles Appendix 33

The integration of liquid-intensive operations acquired through the Maverick transaction resulted in a more than 530% year-over-year increase in handled produced liquids (crude oil, condensate, and produced water). Even with this increase and without accounting for recovered volumes, we successfully achieved our stated 2025 goal of reducing spill intensity by 10%. Intensity declined to 0.07 barrels per 1,000 barrels of gross liquids production (Bbl/ MBbl), demonstrating continued effectiveness in spill prevention relative to production growth.

Diversified's historical spill intensity calculations have traditionally included only agency reportable spills, as per States' respective reporting thresholds, but without the benefit of our teams' spill recovery efforts. For example, in 2025, our teams recovered 62% of total reportable spilled volumes due in part to the aforementioned early detection and preventative maintenance initiatives during the year.

New to our 2025 reporting, we introduced a spill-intensity metric designed to improve

comparability and alignment with industry reporting practices. Going forward, intensity will be calculated using net liquids spill volumes-defined as spills greater than one barrel that reach the environment (outside of secondary containment), net of recovered

volumes. This approach reduces variability across multiple state reporting thresholds and supports more accurate peer comparison.

With this change in methodology, our 2025 spill intensity falls further to 0.03 Bbl/MBbl, representing a nearly 50% improvement to 2024 using this new methodology and a 55% reduction to the previous methodology for 2025. Updated metrics are included accordingly in the Performance Data Table for the years ended 2023-2025.

SPILL INTENSITY

(Spill Volumes (Bbl) / Total Produced Liquids (MBbl))

2023

2024

2025

2023

2024

2025

The primary drivers of spills in 2025 were power grid interruptions, specifically in New Mexico, and corrosion of mature storage tanks and other

equipment. Both challenges continue to be addressed through targeted mitigation actions, including the foregoing reduction initiatives, corrosion mechanisms, tank replacements, and the installation of new telemetry to help connectivity and monitoring during grid issues.

• Agency Reportable Spills, excl. Recovered Volumes

• Spills >1Bbl that impact the environment, incl. Recovered Volumes

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‌Biodiversity

Biodiversity is a core tenet of Diversified's stewardship approach. Through clear policies, regulatory alignment, and field-based best practices, we seek to minimize environmental impacts, restore habitats, and protect sensitive ecosystems across our growing operational footprint.

As acquisitions expand our geographic reach, our biodiversity oversight extends across diverse regions and legacy asset conditions, reinforcing our commitment to preventing ecosystem degradation and proactively safeguarding the multitude of habitats and species within

our control and throughout our operations.

For more information, please refer to the Biodiversity Policy on our website.

Diversified's biodiversity strategy continues to be guided by the four-part standardized framework of the internationally recognized Mitigation Hierarchy - Avoid, Mitigate, Restore, and Offset - which collectively supports our commitment to maintaining and enhancing ecological integrity across our operations.

AVOID

Early environmental assessments and pre-activity planning identify and avoid sensitive areas, including wetlands, wildlife corridors, and habitats for threatened or endangered species, with consideration of local biodiversity and indigenous land protections where applicable.

MITIGATE

Where impacts cannot be fully avoided, we apply mitigation measures, such as waterway buffer zones, seasonal work restrictions, and soil-stabilization practices, to minimize disturbance and prevent erosion or sediment transport.

RESTORE

Restoration is a permanent element of Diversified's asset-lifecycle management. Through soil remediation, regrading, and native vegetation and seed mixes, we return disturbed land to productive ecological conditions that support local ecosystems.

OFFSET

When residual impacts remain, we pursue offset opportunities, including habitat creation and reforestation, to support regional conservation objectives.

In 2025, we continued to strengthen the alignment between our biodiversity and asset retirement programs, recognizing that restoration outcomes achieved through plugging and reclamation activities represent only part of our broader biodiversity impact. Our focus on biodiversity extends across our entire operational footprint, both active and retired assets, to ensure that all sites are managed in ways that promote long-term ecosystem resilience.

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Oversight of biodiversity is embedded within our governance framework and managed through the policies and practices that make up our EMS. Environmental specialists are supported by field

Our biodiversity efforts are grounded in collaboration with conservation organizations, community partners, and regulators to achieve positive outcomes. The following examples highlight some of the ongoing partnerships and restoration work Diversified has across our operating regions:

teams with direct oversight by our Senior Vice President of EHS&R and more broadly by our Chief Operating Officer. These specialists work closely with regulatory, wildlife and forestry agencies, and environmental consultants to assess potential biodiversity impacts and ensure responsible operations near sensitive habitats or protected species.

In alignment with our policy commitments, Diversified respects legally designated protected areas, including national parks and nature reserves, and we do not operate wells in designated UNESCO World Heritage Sites.

HABITAT RESTORATION WITH THE RUFFED GROUSE SOCIETY

We collaborate with the regional chapter of the Ruffed Grouse Society to restore and create upland habitats for grouse and other native wildlife. These efforts include re-establishing native vegetation, improving forest structure, and enhancing biodiversity in previously disturbed areas.

APPALACHIAN REGIONAL REFORESTATION INITIATIVE (ARRI)

Through our participation in ARRI, Diversified supports reforestation projects focused on native tree species and Red Spruce restoration in Appalachia, strengthening forest health, carbon sequestration, and wildlife habitat.

WEST VIRGINIA FORESTRY AND DEPARTMENT OF NATURAL RESOURCES

In collaboration with the West Virginia Division of Forestry and Department of Natural Resources, we support native and pollinator-friendly plantings on state-managed lands to strengthen ecological connectivity and pollinator health.

AULTMAN WATERSHED ASSOCIATION FOR RESTORING THE ENVIRONMENT (AWARE)

In central Pennsylvania, we support AWARE's tree-planting and watershed-improvement efforts, contributing to soil stabilization, improved water quality, and native habitat restoration.

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‌Supporting Our Employees

37 Safety...No Compromises

43 Talent Acquisition & Management

45 Employee Training & Development

1. Engagement & Culture

2. Health & Well-Being

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‌Safety…No Compromises

Safety is the uncompromising foundation of Diversified's operations and related decision-making. It is embedded in our daily activities, reinforced by leadership at every level of the organization, and further strengthened through the establishment of our Safety Leadership Committee.

While we achieved many great safety initiatives in 2025, our measured safety performance did not reach our stated objectives. As we saw this performance begin to unfold, we immediately took action to bolster our safety efforts and re-validate our entire program, aggressively rebuilding our safety program foundations in a refreshed management system aligned with ANSI/ASSP Z10.0-2019 Occupational Health and Safety Management Systems. This framework will increase assurance that our system is both comprehensive and scalable.

Integrated Approach to Safety

Diversified's integrated approach to safety is designed to protect our workforce and contractors, safeguard operational integrity, and reduce potential impacts to the communities where we operate. We seek to combine disciplined management practices with data-driven insights and advanced technologies to prevent incidents, manage operational risk, and strengthen reliable performance. Our cultural themes and associated multi-channel messaging sustain our safety efforts and connect them to personal ownership of safety.

Following the Company's 2025 acquisitions, particularly the transformative Maverick transaction, Diversified took time to perform a comprehensive comparative gap analysis of its legacy Safety Management System as compared to industry

standards and the Maverick program. In many areas, Maverick had attained better safety performance in 2024 than Diversified, therefore providing considerable opportunities across both companies to assess all safety programs and efforts for effectiveness before solidifying our approach.

Based on the gap analysis, we expanded our safety focus to re-establish comprehensive unified safety standards within the enlarged organization, adopting the Maverick approach where appropriate. Safety teams from both legacy Diversified and Maverick operations collaborated to identify and integrate best practices, supported by joint workshops to align operating priorities and reinforce consistency, accountability, and continuous improvement.

Safety Strategy & Approach

Diversified's safety strategy applies a coordinated, risk-based approach that prioritizes workforce protection, asset integrity, and community safety to address risk across all aspects of our operations.

Personnel Safety

Protecting employees and contractors is Diversified's highest safety priority. We manage personnel-related risk through comprehensive training, active knowledge exchange, and data-enabled safety controls that support informed decision-making before, during, and after the workday. Regular safety training and awareness initiatives reinforce hazard recognition and safe behaviors, while cultural programs promote shared responsibility across the workforce.

Process Safety/Asset Integrity

Diversified maintains operational integrity and asset reliability through disciplined, proactive maintenance practices, systematic process-safety controls, and continuous monitoring within its asset base. Our pipeline safety management framework is supported by real-time oversight, integrated information systems, and operator qualification requirements that promote consistent compliance and

operational excellence.

Community Safety

By prioritizing both personnel and process safety, Diversified simultaneously reduces potential risks to the communities surrounding our operations. We emphasize proactive planning, transparent communication, and stakeholder engagement

to support public awareness and emergency preparedness.

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SAFETY CULTURE

Built on shared responsibility, collaboration, and consistent execution, Diversified's safety culture guides how our workforce plans daily activities, identifies hazards, and cares for one another. We reinforce the expectation that safety is not only followed through procedures-it is embedded in daily ownership of behaviors, and decision-making.

Keeping Our Communities Safe

In partnership with Paradigm Liaison Services, Diversified hosted more than 120 public service meetings in the first quarter of 2025, bringing together pipeline operators and community stakeholders- including public officials, emergency responders, educators, contractors and excavators, and one-call centers-to provide resources and education on pipeline safety, damage prevention, emergency preparedness, and coordinated response action.

Maintaining a safety culture requires ongoing commitment and resources. We apply a unified framework that integrates management systems, operational standards, technology-enabled tools, formalized procedures, and diverse training methods. Together, these elements support learning, strengthen consistency across all operations, and reinforce continuous improvement. All leaders rely on our safety themes and their own personal safety leadership success formula, incorporating personal appeals to decide to work safe and to prioritize safety over production. This approach is visible through our Stop Work Expectation, where our employees don't just have the authority to stop work when a safety issue could arise, it is fully expected that they will stop work.

Our Safety Vision Statement Safety As A Way Of Life

Safety is not a program - it is our identity. At Diversified, safety is embedded in every decision, every conversation, and every task. It begins before the work starts and continues beyond the workday. Our people are intentional, aspirational, and unwavering in their commitment to safety, both professionally and personally. We don't just follow safety protocols - we live them, making safety a natural part of who we are.

SAFETY OVERSIGHT, PREVENTION, AND REPORTING

Diversified's health and safety oversight is led by the Company's EHS team and reinforced through a Safety Leadership Committee established to strengthen leadership accountability and elevate safety governance. The Safety Leadership Committee meets quarterly with leadership and field personnel in regional settings to review performance, conduct gap analyses, and identify best practices. In turn, safety performance and progress are regularly reported by the Chief Operating Officer and Senior Vice President of EHS&R to the Board's Sustainability & Safety Committee, which provides governance oversight and monitors safety performance and related initiatives.

Prevention and learning are reinforced through robust data tracking and reporting. We use the IBM Maximo Health, Safety, and Environment platform to manage

safety tasks and support consistent implementation of standards across the workforce. In addition, our employee-led Good Catch/Near Miss/Stop Work Expectation (GC/NM/SWE) program promotes early identification of hazards before incidents occur.

Together, these processes operate seamlessly alongside our enterprise operational and risk management safety solution, KPA Novara, which supports our ability to move from reactive incident tracking to proactive risk management.

GC/NM/SWE submissions are reviewed by the safety and operations teams and documented

alongside actual incidents. All submissions are scored for severity, and we analyze this information to identify trends, inform corrective actions, and enhance training. Lessons learned are advanced by the EHS team across all operations through corporate-wide Safety Advisories to strengthen controls, reduce repeat risks, and improve safety performance over time.

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2025 Safety Initiatives

A central theme of our 2025 safety initiatives was strengthening proactive communication and engagement with employees. By enhancing safety awareness channels and encouraging open dialogue, we aimed to reinforce a culture where safety is personal, meaningful, and continuously improving.

These efforts supported the launch and expansion of several key initiatives, outlined below.

LEADERSHIP-DRIVEN SAFETY

In 2025, Diversified continued and enhanced foreman-led training initiatives to strengthen frontline ownership of safety performance. These initiatives promote practical knowledge sharing, reinforce safety priorities, and enhance leadership accountability by integrating operational and safety

expectations. By enhancing these established training methods, this approach deepens engagement and further embeds safety into everyday work practices.

In addition, the Safety Leadership Committee advanced targeted initiatives to address top workplace hazards, strengthen consistent execution, and expand the use of technology-enabled solutions and focused safety campaigns to reduce risk.

The Safety Leadership Committee also established seven safety charters to guide strategic focus across all operating units and locations, addressing areas such as fit-for-duty/return to work, communications, reporting culture, medical case management, policy adherence/disciplinary action, training and development, and contractor safety. These charters are intended to bolster key opportunities for improving safety performance, as identified through our management system gap analysis. The committee turns its attention in 2026 to driving universal endorsement and change in safety awareness

and expectations.

Safety Leadership Committee Key Initiatives

VISION STATEMENT

Aligns workforce on desired safety results

SAFETY PERFORMANCE

Validates current safety measures and performance

SAFETY CHARTERS

Sets strategic safety direction and long-term goals

FOUR-GAS MONITORS

Equips all field employees with new Four-Gas Monitor device

CONTRACTOR MANAGEMENT

Standardizes onboarding and compliance across all regions

TRAINING AND DEVELOPMENT

Creates new hire training matrix, optimizes resources, and strengthens work controls

PREVENTION, MITIGATION AND LEARNING

Diversified strengthened prevention and learning-based safety practices in 2025 through

multiple complementary programs. Through our Life Critical Program (LCP) standards, the Company maintains protocols for high-risk work activities, including driving safety, excavation and trenching, hydrogen sulfide (H₂S) awareness, and confined-space operations. These protocols establish clear requirements for planning, execution, and risk mitigation and were integrated as a best practice into daily operations following the acquisition of Maverick. The protocols are communicated to each employee as applicable to ensure safe work procedures are understood and formally acknowledged.

We enforce a mandatory Stop Work Expectation that empowers employees to pause work when serious safety concerns are identified. Our complementary GC/NM reporting program supports continuous learning by capturing both potential hazards and incidents, all of which are reviewed by safety leadership to inform workflow changes and safety improvements. In 2025, GC/NM/SWE reporting increased by 5% year over year, enhancing our ability to identify and address risks before they result in incidents. Moreover, we observed an improvement in the quality of submissions, indicating a deeper understanding and ownership of safety matters throughout the organization.

The EHS team distributes a company-wide EHS Weekly Summary report that serves as a leading indicator of safety performance by highlighting recent events, observations, and GC/NM/SWE activity. The summary includes details of actual and avoided vehicle incidents, spills, property damage, and line strikes. By sharing these observations ad lessons learned, we aim to build the skills to pre-emptively recognize hazards, respond effectively, and support one another.

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By systematically sharing these insights, the weekly summary supports meaningful safety conversations across the Company, strengthens hazard recognition, reinforces preventive behaviors, and promotes continuous learning. District-level teams regularly review the summaries together and discuss lessons learned for incorporation into operational practices. This proactive, learning-based approach enables employees to identify emerging risks early and

apply insights that contribute to ongoing safety improvement.

DRIVER AND CONTRACTOR SAFETY

Given the geographic breadth of our operations, we continue to enhance our Driver Safety Program to address roadway risks. This comprehensive program includes remote monitoring protocols, optimized well-tender routing, and initiatives to reduce overall mileage driven.

Protecting Our Most Valuable Assets

Through the work of the Safety Leadership Committee, 100% of field employees are equipped with new four-gas monitors that detect key hazardous and flammable conditions and include a man-down feature to alert responders if assistance is required. This technology enhances worker protection by enabling rapid response to potential gas exposure or fall-related incidents.

To proactively monitor driver behavior and performance, 100% of our vehicle fleet is equipped with GPS tracking and telematics. Driver scorecards based on these analytics are used to evaluate driving trends and have contributed to measurable reductions in at-risk driving behaviors. These insights support targeted training, corrective actions, and accountability. All employees operating company vehicles receive mandated driver safety training, with additional required training following any motor vehicle accident. Our objective is to achieve zero preventable motor vehicle accidents, so we are intentional in recognizing outstanding driver safety performance through annual employee safe

driving awards.

In 2025, we enhanced our supply chain risk management program, delivered through third-party Veriforce, to further strengthen contractor safety screening. Through a streamlined, Procurement Department-led prequalification process, prospective contractors are vetted prior to onboarding using standardized grading criteria and balanced scorecards. By applying consistent evaluation criteria across contractors of all sizes, we reinforce a safe, compliant supply chain and hold our business partners to the same safety expectations as our internal teams. Thereafter, we maintain ongoing evaluations of active contractors to ensure continuing compliance, and we aim to begin contractor audits

in 2026.

EMERGENCY PREPAREDNESS AND RESILIENCE

To promote effective coordination and timely, value-driven communications during emergency situations, Diversified's Crisis Management Policy (CMP) outlines potential emergency scenarios, stakeholder communication protocols, and

emergency response teams at the regional, site, and unit levels. The policy addresses a broad range of risks, including environmental, personal safety, legal, regulatory, data security, and operational disruptions.

The Crisis Management Team (CMT) regularly reviews and enhances the CMP to address both actual and emerging risks. The CMT can also authorize and activate the Business Continuity Plan (BCP) in response to localized events (e.g., floods, fires, disruption of digital networks), with the aim to expeditiously restore operations through established response protocols.

Serving as our centralized, one call

damage-prevention platform, KorTerra is a critical component of Diversified's broader emergency preparedness framework by strengthening the Company's ability to prevent incidents before they escalate into crises. KorTerra routes all 811 locate requests directly to the appropriate personnel, significantly reducing the likelihood of missed or delayed responses. This streamlined process minimizes the risk of third-party damage to underground infrastructure and supports Diversified's CMP and BCP by reducing

avoidable service disruptions.

KorTerra's integration with Diversified's geographic information system capabilities and the expertise of our trained locators further strengthens infrastructure protection, situational awareness, and response coordination, thereby supporting both incident prevention and overall operational resilience.