it are Hangars 20 through 23, and the lower building to their left is an associated storage building. Hidden behind Hangar 22 is another new building, constructed in 2003. It is smaller, and connected to the surrounding hangars by underground pipes. Possibly a fuel storage or heating unit.
In front of that group of hangars, next to the weapons storage facility mentioned above, is Hangar 19. It is used for Weapons Arm and De-Arm of aircraft. In spring 2005 two extensions were constructed to the north and south, effectively tripling the size of this hangar. The purpose of this extension is not yet known, but it is interesting that the lower section of the extensions is open.
This could indicate a need for good ventilation, possibly due to running jet engines. It appears that the extensions are designed to hide something from curious eyes. This is supported by the fact that the open section of the southern extension is hidden by an additional screen in the direction of Tikaboo. Whatever goes on here is obviously top secret! A new concrete ramp connects these hangars to the new Center Taxiway, constructed in spring of 2003. The new taxiway connects the South Ramp with the new runway 14L/32R.
In the background, on the slope of the Papoose Range, is a group water tanks. Originally there were only four white tanks. The three huge dark colored tanks were added between 1995 and 1999.
Further over to the right is Hangar 8, which is said to be used by Northrop Grumman. To the right of it is Fire Station #2 (#1 is near the four northern hangars). Sometimes the doors can be seen open, and we have seen the inside brightly lit at night, with what appeared to be a fire truck inside. The next building is the P.E. Building ("Personal Equipment").
This is where the pilots keep their flight gear, and prepare for their missions. It is surrounded by marked parking spaces and the only trees at Area 51.
Next to it is the huge Hangar 18. It is approximately 100 ft. tall, easily large enough for even the largest aircraft. A B747 could easily fit inside. It opens on both ends to make it easier for large planes to get in and out. The exact purpose is not known, but it is assumed that it is used for new developments. We have also seen Janet aircraft, Boeing 737 that are used to shuttle workers back and forth between Area 51 and Las Vegas, on the ramp north of it. So it may be used for maintenance work on the Janet fleet. Behind Hangar 18, partly visible on the right, is a connected office and support building.
The brown building further over to the right is the Security Building, the headquarters of the famous cammo-dudes. Area 51 security is split into several layers. The Cammo Dudes (so named after their camouflage outfit) are members of a private contractor, guarding the outer perimeter of Area 51. They can bee seen near the Groom Lake Road entrance of the base, keeping an eye on curious tourists. Security further inside is likely provided by Air Force Police.
The next building over contains several labs. It is known as "Photo Lab and Precision Measurement Equipment Lab (PMEL)".
Behind these two buildings are the old toxic waste burning pits. This is where until the early 1990's highly toxic waste products were burned in open trenches, including still classified and highly toxic byproducts of the stealth paint used for the development of the F-117 Stealth Fighter. After several workers got sick and even died from breathing the toxic fumes, the open burning has stopped and the area has been covered up with dirt.