The city of Vapi in the state of Gujarat, India, has a deep industrial history, with chemicals, pesticides, dyes, textiles, and other sectors active in the municipal area. Though such heavy industrial activity presents environmental challenges, Vapi is excelling due to its sustained effort over the last decade to continuously elevate its environmental performance. One of the signature projects in the area, and which underscores Vapi’s engineering and infrastructure goals, is the development of India’s first vertical expansion of a landfill.
The geosynthetic-reinforced, vertical expansion enabled 260,000 m3 of toxic waste to be contained on a landfill originally designed for 150,000 m3 of waste.
VERTICAL EXPANSION WITH GEOSYNTHETICS
Vapi Green Enviro Limited, working with geosynthetics provider Strata India, proposed the innovative solution. Led by Strata India CTO Shahrokh Bagli, a reinforced soil structure with StrataGrid™ geogrids and StrataBlock™ modular precast concrete blocks was designed and executed, including with other parts of the landfill that had already been closed.
The containment was completed with conventional earth embankments and side slopes.
One of the challenges in finishing up the project, however, was the desire to complete the landfill’s vertical expansion with a vegetated exterior. Mulch mats had commonly been used for the outer slopes of landfills in India, but the Vapi site, with its more aggressive waste types, was sealed on the outer slopes with smooth geomembrane. Cover soil and matting could not be placed on it without slope failure being a risk.
To resolve this, the project team secured a geocellular confinement system (StrataWeb®) to the slopes with a layer of geogrid reinforcement beneath the geocells. These layers were anchored into a reinforced soil mound at the crest.
The end result is an aesthetically pleasing, green slope on the secured landfill and a very progressive, vertical expansion for all of India’s solid waste engineers to learn from.
Learn more about Strata India’s engineering services and geosynthetics at www.strataindia.com.4