HILL AIR FORCE BASE — The Air Force on Friday released the draft Environmental Impact Statement for the first bases slated to receive the F-35A Joint Strike Fighter.

The study analyzes the potential environmental consequences of a United States Air Force proposal to "beddown" F-35A Lightning II aircraft at one or more Air Combat Command or Air National Guard bases starting in 2015, to be completed by 2020.

Hill recently unveiled new facilities on base to maintain the next-generation aircraft, scheduled to replace the base's F-16s. Although a timeframe for the changeout at Hill has not been announced, the EIS executive summary said the first deliveries of F-35As could be as early as 2015 and be completed by 2020.

For aircraft enthusiasts, the draft EIS includes diagrams of the fighter and program particulars. For environmentalists, the document includes projections of the aircraft's ground impacts, like sonic booms and impacts on wetlands and wildlife. The EIS also makes economic projects significant to local and state governments where they would be located.

The draft EIS considers six air bases for the initial beddown of the new fighter jets, listing Hill and Burlington Air Guard Station, Vt., as the preferred choices. The study considers three alternate scenarios for Hill — basing either 24, 48 or 72 of the F-35As there.

"The F-16 mission and 48 aircraft currently at the installation would either be reassigned or retired," according to the document, making for a net loss of 24 aircraft if only 24 F-35As get based at Hill, but adding 24 additional aircraft if Hill gets 72 of the new fighters.

"Since the F-35A replaces legacy fighter aircraft, the Air Force proposes to … remove all legacy fighter aircraft from the selected bases … as the F-35As become available after manufacturing and testing," the study says.

According to the study, Hill would need around $18 million to $40 million in new construction, depending on the 24-, 48-, or 72-fighter alternative chosen. Military operation and maintenance personnel at Hill would decrease respectively by 1,157, 572, or increase by 13 under the three scenarios.

"However, the scenarios would not substantially impact regional employment, income, or regional housing market," the draft EIS summary says.

Residential land subject to high noise levels would decrease with either 24 or 48 F-35As and no F-16s, but would increase with 72 new fighters.

With 24 F-35As and no F-16s, pollutants would decrease, but would increase with the higher-number scenarios.

Formal public hearings on the draft EIS are scheduled May 1 at Northridge High School in Layton, May 2 at Ogden High School and May 3 at West Wendover Branch Library in West Wendover, Nev., according to information Hill released on Friday.

New F-35A aircraft would replace aging legacy aircraft, such as F-16s, at the bases that currently support them, and the new fighters would be the first F-35As slated for combat roles throughout the world.

Along with Hill, other bases included in the study are Burlington Air Guard Station, Vt; Jacksonville AGS, Fla.; McEntire Joint National Guard Base, S.C.; Shaw AFB, S.C., and Mountain Home AFB, Idaho.

The F-15s currently based at Mountain Home AFB would not be replaced with the arrival of any new F-35s.

The six bases were chosen for the study in 2009, the draft EIS notes.

"The actual number of aircraft assigned and bases used will be determined in light of national strategic considerations and F-35A aircraft availability as of the completion" of the final EIS.

The F-16 is considered a legacy aircraft, as it is no longer manufactured. The last F-16 is will be withdrawn from service by around 2025. The Air Force says the next generation F-35 fighters are needed because more effective enemy air defense systems and the growing worldwide prevalence of sophisticated air-to-air and surface-to-air missiles pose a greater threat to older aircraft.

"Slated to purchase and deploy F-35As over the next several decades, the Air Force must ensure this initial beddown provides a solid start to the program," according to the document, assuring "availability of combat-ready pilots in the most advanced fighter aircraft in the world."

The new fighter has stealth design features, greater speed and combat range, and lower maintenance costs due to a computerized self-test system, according to the Air Force.

The F-35A is the conventional take-off and landing version of the F-35.

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