Casella Waste Systems and Waga Energy Unveil RNG Facility at Ribbon Cutting

EYBENS (France), May 18, 2026 — Casella Waste Systems, Inc. (NASDAQ: CWST), a regional solid waste, recycling and resource management services company in the Eastern United States, and Waga Energy (EPA: WAGA), a global expert in the production of Renewable Natural Gas (RNG) from landfills, held a ribbon-cutting ceremony on May 14, 2026, to celebrate the opening of the RNG production facility at the Chemung County Landfill in Elmira, New York. The facility, which has been successfully turning landfill gas into RNG since January 2026, represents a key milestone in Casella’s efforts to create valuable resources from waste.

“We’re excited to celebrate the opening of this facility as it represents a key piece of our strategy coming to life,” said Ned Coletta, President and CEO of Casella Waste Systems, Inc. “We made the decision several years ago to find great partners to develop these RNG projects at our facilities rather than invest the capital and embark on projects that are outside the scope of our expertise. This project is a great example of the benefits of that approach as we see the collective expertise of Chemung County, Waga Energy, and our landfill operations team coming together to create value out of the waste we manage.”

The facility leverages the WAGABOX® technology developed and patented by Waga Energy to upgrade landfill gas into pipeline‑quality RNG. The RNG produced on-site is injected directly into the Valley Energy natural gas distribution network, supplying the region with a renewable alternative to fossil natural gas. The facility is designed to generate up to 610,000 MMBtu of renewable gas annually and is expected to avoid more than 47,000 tons of CO₂‑equivalent emissions each year, according to U.S. Environmental Protection Agency (EPA) standards^[1]. Through its first four months, the facility has performed well through its ramp-up phase and is projected to produce 340,000 MMBtu in year one, which is equivalent to 2.4 million gallons of diesel fuel.

“We are honoured to celebrate this inauguration alongside Casella, a company whose commitment to sustainability and environmental stewardship is truly exemplary,” said Guénaël Prince, Chief Executive Officer of Waga Energy Inc. “The successful commissioning of the Chemung facility demonstrates the strength of our partnership and Casella’s leadership in renewable energy development. This project showcases how innovative collaboration can turn waste into a valuable resource for the energy transition, benefiting both the environment and local communities.”

Under the terms of the agreement, Waga Energy deployed the capital required to fully fund the construction of the facility and will own and operate the facility for 20 years, while Casella and Waga Energy share the revenue generated from RNG sales.

[1] Landfill Gas Energy Benefits Calculator | US EPA

About Casella Waste Systems, Inc.

Casella Waste Systems, Inc., headquartered in Rutland, Vermont, provides resource management expertise and services to residential, commercial, municipal, institutional and industrial customers, primarily in the areas of solid waste collection and disposal, transfer, recycling and organics services in the eastern United States. For more information, visit www.casella.com.

About Waga Energy

Waga Energy produces competitively priced Renewable Natural Gas (RNG, also known as biomethane) by upgrading landfill gas using a patented purification technology called WAGABOX®. The RNG produced is injected directly into the gas grids that supply individuals and businesses, providing a substitute for natural fossil gas. Waga Energy currently operates 36 RNG production units in France, Spain, Canada and the USA, representing an installed capacity of more than 6.5 million MMBtu (1.9 TWh) per year. To date, Waga Energy has 19 RNG production units under construction worldwide. Each project initiated by Waga Energy contributes to the fight against global warming and helps the energy transition. Waga Energy is listed on Euronext Paris (FR0012532810 – EPA: WAGA).