1941 - 1962: The BMGR, formerly called the Luke Air Force Range, was developed in 1941 to provide training for air crews in aerial and air-to-ground combat and for the evaluation of new weapons and tactics necessary to develop skills for national defense. The range was expanded in 1962 and is still being used for training today.

1986 - 2001: The Military Lands Withdrawal Act of 1986 (P.L. 99-606), was used to withdraw the land for the BMGR and expired in 2001. The Defense Authorization Bill for fiscal year 2000 approved language extending the withdrawal for another 25 years.

2004 - 2005: An investigation began at several munitions targets in the "Area A" buffer zone on the far eastern side of the range.

2006 - 2008: Several targets and roads at the "Area A" buffer zone on the eastern side of the range were investigated for munitions. The former range was used in the 1950s for bombing practice at constructed targets in a canyon valley west of the Sand Tanks Mountains. Munitions include sub-caliber air rockets (that look like pipe bombs), BDU-33 25-pound bombs, 100-pound practice bombs, 500-pound practice bombs and other munitions. The area is now part of the Sonoran  Desert National Monument managed by the U.S. Bureau of Land Management (BLM). BLM requested the investigation of 67 miles of roadways using a composite towed array. The Phase II reacquisition and digging of over 9,000 anomalies took place in 2008. The majority of items were non-munitions related such as barb wire, cans, and iron rich rocks. Most of the munitions were confined to the area around the targets.

2007: In February, a Preliminary Assessment-Comprehensive Site Evaluation Phase I was completed for the closed or transferred ranges.

2008: A kick-off meeting for the Comprehensive Site Evaluation Phase II for several closed and transferred ranges was held on July 22, 2008. The investigation included walking transects looking for munitions debris, and munitions and explosives of concern. It also  included sampling at the Sentinel Plain, Ground 5 Lead-In, I-8 Staircase buffer zone, Firing In-butts and Ajo airport.

The reacquisition at Area "A" BLM roads took place in 2008. Digging of over 9,000 anomalies did not yield munitions or explosives of concern. The majority of items were non-munitions related such as barbed wire, cans, and iron rich rocks. Most of the munitions were confined to the area around the targets.

2009: The start of the Comprehensive Site Evaluation Phase II included walking fixed straight- path transect lines (paths along which one records and counts occurrences of munitions) around denser vegetation, recording and mapping field observations for munitions.

2010: The Draft-Final Comprehensive Site Evaluation Phase II was submitted to ADEQ for review. The Sentinel Plain, and Ground 5 Lead-In were recommended for further munitions response action by the Air Force.