Fog and airports do not go well together, but Hartsfield-Jackson Atlanta International Airport had to deal with an entirely different meaning of the word with the addition of its new terminal.
Restaurants located in the new terminal serve up more than just food to hungry travelers. Almost all restaurants create byproducts that need to be removed from wastewater prior to discharge into the sewer system. A precast concrete grease interceptor removes fats, oils and greases (FOG) from the waste stream and brings water to acceptable effluent standards. Precast concrete grease interceptors are easy to maintain and large enough to hold considerable amounts of waste.
In addition to fast installation, precast grease interceptors are strong and airports need strength when it comes to underground structures. When Bartow Precast, located in Cartersville, Ga., received the job, the request was for tanks that could handle a 50,000 lb wheel load. The resulting H-62.5 design included a 14-in. thick lid, 10-in. thick floor and 6-in. thick walls. The baffle wall was cast monolithically instead of a slide-in design to further increase structural stability. Access openings consist of a 24 in. cast-in ring and covers that are proof load tested to 200,000 lb. The interior is coated with epoxy for additional durability.
To date, Bartow Precast has manufactured nine tanks to provide each restaurant with one to two tanks depending on size. Each site was saw cut, excavated and following the tank setting, the area was backfilled. The concrete cover was re-poured with the top of the lid sitting at grade.
Wastewater construction projects that impact transportation systems pose many demands and challenges, but the need for materials that are strong, durable and offer fast installation is near the top. Setbacks and delays are the words nightmares are made of, particularly if they impact the general public. The use of precast concrete tanks enabled the airport to minimize disruptions to normal operations while also providing peace of mind that the tanks will stand up to anticipated wheel loads and the tests of time.
For more information, contact the National Precast Concrete Assn. at 800.366.7731.
