Apple is building a high-security “tactical” data center on the site of its massive data center in Maiden, N.C., according to records reviewed by the Hickory Daily Record.

According to CNet News, design plans filed with Catawba County show that the new 21,030-square-foot data center will store clusters of servers in 11 rooms and be guarded by mantraps at either end. When entering the building, the article writes, people will have to pass one door that closes behind them before being cleared to enter the building through a second door.

The building will also be surrounded by an 8-foot-high chain-link security fence.

CNet News also reports that the project will cost Apple approximately $1.8 million – far less than the reported $1 billion it spent to build the 500,000-square-foot data center on the same property. Apple is also building two solar array installations in the area to help power the data center, and when combined, the arrays will bring in 84 million kilowatt-hours of power annually, the article says.

The Hickory Daily Record also reports that the plans show the smaller data center T-boning the larger center, as well as showing “the footprint for a larger data center that would run nearly parallel to the existing one” and T-bone the smaller one under construction, suggesting that apple has even more plans to expand the site.

Other permits issued for the property describe a new building with a reinforced concrete pad that would house a hydrogen fuel cell facility, CNet News reports. The permit describes the cost of construction at $4.1 million.