|Biloxi Mississippi. The leachate is pumped from pond (upper right) to drip irrigate 5 acres of vetiver (left center)|
The American Academy of Environmental Engineers awarded Leggette, Brashears and Graham Inc the 2012 Grand Prize for Small Projects for "Innovative Phytoremediation Process Utilizes Landfill Leachate as a Resource in Lieu of Traditional Disposal As a Waste" see: http://www.aaee.net/E32012GPSmallProjects.php
This project relates to a landfill in Mississippi. Brad Granley and Paul Truong were very involved in the design of the project. Our congratulations!!!
"Integrated Approach - The use of phytoremediation at landfills represents an integrated approach having a profound environmental impact.
Groundwater is protected through minimization of surface water infiltration and better control of leachate within the landfill, which can otherwise result in contamination of aquifers, especially at old facilities like GCAL, which has no bottom liner.
Surface water. Vetiver reduces infiltration which helps prevent leachate seeps (leachate that flows out the side of a landfill and to surface water), and can dry up existing seeps. Vetiver also removes sediment and nutrients from surface water runoff.
Soil erosion is reduced. Leachate distribution does not create a problem with soil. The plants effectively utilize leachate compounds as nutrients. Also, a subsurface “biological treatment reactor” develops which effectively breaks down and mineralizes a wide range of compounds.
Adverse impacts to air quality are greatly reduced. Using phytoremediation at GCAL instead of hauling 3.5 million gallons of leachate per year results in the following:
1 year: 232,000 miles not driven; 38,000 gallons of diesel not burned (6 mpg); 380,000 kg CO2 emissions (10 lbs CO2/gal diesel burned)
30 years: 7 million miles not driven; 1.14 million gallons diesel not burned; 11,400,000 kg CO2 (25 million pounds CO2)
Fast growing vetiver will sequester 113,000 kg CO2/year through carbon fixation.
Quality and User Satisfaction
The GCAL project has exceeded Republic’s expectations. The system has performed as designed and nearly 100% of leachate generated has been utilized on site, well ahead of anticipated results. Republic is also thrilled with the cost savings. Phytoremediation system low-cost O&M has cut annual costs by 60%, saving millions over a standard 30-year post-closure care period. Per Republic, “the approach is a game changer for leachate management.” The work has also attracted the serious interest of other multi- billion dollar US solid waste companies. Internationally, the first three vetiver system installations in Latin America are underway for the largest solid waste company in Mexico."