New "smart lanes" aimed at speeding screening through Atlanta airport security checkpoints will cost up to $3.5 million more than originally expected.

Hartsfield-Jackson International is seeking Atlanta City Council approval of additional funding to pay for the remainder of 20 smart lanes being added at the Atlanta airport.

TSA and airport officials say the new lanes, which have multiple stations for travelers to load bins and an automated bin return process, could speed processing by as much as 30 percent.

Hartsfield-Jackson was the first airport in the nation to get two new lanes for testing in May, with a $1 million investment by Delta Air Lines.

The airport then dedicated $9 million to add 20 more smart lanes, in a resolution approved in September.

Now, the airport is seeking an additional $3.5 million for the final eight of the 20 MacDonald Humfrey smart lanes, for a total of a $12.5 million expenditure. The contract is with East Point-based Bryson Constructors, which is implementing the smart lanes rollout as a special procurement.

The quote provided by MacDonald Humfrey, a U.K.-based developer of the automated airport-checkpoint security scanners, "was forty percent (40%) higher than budgeted," according to the airport. That's why the original $9 million would only pay for 12 of the lanes, which prompted a change order with Bryson Constructors for the additional funding due to "escalated equipment cost," the city council resolution says.

The city council finance committee this week voted unanimously in favor of the resolution for the additional funding, and it now goes to the full council for approval in early January.

"There's only one manufacturer" of the smart lanes the airport is using, said Hartsfield-Jackson interim general manager Roosevelt Council.

Other airports and airlines are also installing the new smart lanes. "Demand drives the price," Council said. "Since we've had so much success here, we've had other airports come down to take a look. And now there's other orders that are actually waiting for those smart lanes. I just think it's a company that's taking advantage of its position now."

MacDonald Humfrey was acquired last month by New York-based defense contractor L-3 Communications.

After the pilot test of the smart lanes starting in May, Delta secured slots for more orders of the lanes, then transferred the slots to Hartsfield-Jackson for the rollout.

The airport will have five smart lanes by the end of the year, with two installed in May at the domestic terminal South security checkpoint, a third installed there in November and two more were recently added at the domestic terminal North security checkpoint.

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