Arq, Inc. experienced significant operational hurdles in ramping up production of its granular activated carbon (GAC) products due to design flaws and feedstock challenges at its Red River Plant, resulting in halted production and increased costs in 2025. Regulatory shifts, including the EPA’s rollback of stricter mercury emission standards under the MATS Rule, pose demand risks for Arq’s core consumable products targeted at coal-fired power plants. Financially, the company reported a substantial net loss of over $52 million in 2025 and negative operating cash flow, despite a history of revenue growth through 2021. Liquidity remains supported by a revolving credit facility and cash on hand for now, but continued resolution of production setbacks and regulatory clarity are critical to shifting financial trends.