Major Gypsum Stack Closure Reaches 70% Completion with 5.69 Million SF of Green Geomembrane Installed
Since mobilizing in 2025, COMANCO’s team has installed more than 5.69 million square feet of 60-mil AGRU Green Geomembrane and geosynthetic materials on one of Florida’s largest ongoing gypsum stack closure projects. The striking green liner has transformed the site’s landscape while serving a critical role in long-term environmental protection, stormwater management, and site stabilization. To put the scale into perspective, the material installed to date could cover nearly 99 football fields.
Now approximately 70% complete, the project remains on schedule for its March 2027 completion milestone while demonstrating COMANCO’s commitment to safety, quality, and environmental stewardship.
Project Overview
The project is a gypsum stack closure, 70% complete, started in 2025, with a target completion date of March 2027. Schedule performance remains on schedule and is actively meeting key project milestones. The primary objective is to create a long-term closure system that protects the environment, supports clean stormwater management, and facilitates sustainable post-mining land restoration.
Featured Installation: AGRU Green Geomembrane
One of the most recognizable features of this gypsum stack closure is the installation of the 60-mil AGRU Green Geomembrane, a high-performance liner system designed to provide long-term environmental containment while blending more naturally into the surrounding landscape than traditional black geomembranes.
With millions of square feet already deployed, the green geomembrane creates a visually uniform closure surface while supporting stormwater management and environmental protection objectives. As installation progresses, the expansive green coverage highlights the scale of the project and the precision required to successfully deploy and weld geosynthetic systems across a large project footprint.
COMANCO Experience: For decades, COMANCO has installed geomembrane liner systems for mining, phosphate, water management, and environmental containment applications throughout the United States. This experience provides the expertise needed to execute large-scale closure projects while maintaining strict quality control standards and regulatory compliance requirements.
Scope of Work and Materials
Installing more than 5.69 million square feet of geosynthetics requires extensive planning, coordination, and quality control. The closure system incorporates geomembrane deployment, geocomposite drainage installation, seam welding, non-destructive testing, anchor trench construction, ballast placement, and ongoing quality assurance activities designed to support long-term environmental performance.
The primary materials include:
- 60-mil AGRU Green Geomembrane
- 270 Geocomposite Drainage Layer
Together, these materials create an engineered closure system that promotes effective stormwater management, protects environmental resources, and supports sustainable post-mining land restoration.
Overcoming Complex Challenges
Large-scale closure projects present unique construction challenges that require flexibility, collaboration, and experience. Throughout the project, the team has managed variable weather conditions, coordination with multiple contractors working simultaneously, tight scheduling requirements, and the logistical demands of a large project footprint. By maintaining open communication and a solutions-focused approach, the team has consistently overcome obstacles while keeping production moving forward safely and efficiently.
Commitment to Safety
Safety remains a cornerstone of project success. Key safety initiatives include providing all personnel with required PPE, conducting ongoing employee training and safety education, implementing company safety policies and procedures, and maintaining daily safety awareness and hazard recognition practices. The company also introduced on-site cooling trailers to help mitigate heat-related risks and improve workforce well-being. This cooling trailer initiative is among the company’s first of its kind and has provided an added level of protection and comfort for employees working in Florida’s demanding climate.
Delivering Quality Every Day
The project team’s commitment to quality shows in consistent installation practices, thorough seam welding and testing, continuous inspection and quality control, strict adherence to project specifications, and attention to detail throughout every phase of construction.
Crew Recognition
The field team’s dedication and professionalism drive this project’s success. Crew highlights include outstanding teamwork and collaboration, promotions, high production rates while maintaining quality standards, employee career development, and consistently meeting and exceeding expectations in the field. Superintendent Ramon Irrizarry and Foreman Fredy Serrano’s leadership, combined with the efforts of a highly skilled 20-person crew, has been instrumental in maintaining project momentum and achieving exceptional results.
Supporting Long-Term Environmental Protection
Gypsum stack closure projects play a critical role in protecting surrounding ecosystems by controlling stormwater, minimizing erosion, and providing long-term environmental containment. Upon completion, this engineered closure system will help manage surface water runoff, stabilize the site, and prepare the area for its intended post-mining land use.
COMANCO Experience: COMANCO’s extensive phosphate and mining containment experience has provided valuable insight into the unique challenges associated with large-scale closure systems. By combining proven geosynthetic technologies with experienced field leadership, COMANCO helps owners achieve sustainable environmental outcomes while maintaining project performance expectations.
SAFETY ★ QUALITY ★ SERVICE
COMANCO is an environmental, commercial, and civil construction company specializing in constructing containment facilities.
Complex phosphate closure projects require careful coordination between geosynthetics, earthwork, drainage systems, and field operations. COMANCO brings decades of environmental construction experience to containment projects where safety, quality, and long-term performance matter. Contact COMANCO to discuss your next phosphate closure or environmental construction project.
📍 4301 Sterling Commerce Dr, Plant City, FL 33566
📞 (813) 988-8829
🌐 www.comanco.com