The museum is adding a giant screen IMAX theater, which it is hoping to open this fall.

Plans are also in the works for a new gift shop. And in the long term, Operations Manager James Nelson said the museum hopes to build another 121,000 square foot exhibit hall.

Construction is expected to take about four months.

The new theater will have about 55,000 square feet of floor space in all. It will also house conference rooms, office space, exhibit space, a gift shop, storage areas and multipurpose rooms.

The museum's long-range plan also calls for development of an aircraft restoration and model-building shop, a chapel and four outbuildings of unspecified use.

Evergreen initially sought to have 35 additional acres brought into the city's urban growth boundary to support future museum expansion.

The city agreed, but land-use watchdog group Friends of Yamhill County filed an appeal with the state Land Use Board of Appeals.

Eventually, the museum and the group reached a private settlement in which 9.5 acres was trimmed from the expansion and the museum agreed to rule out several possible uses on site, including anything involving overnight lodging.

(Copyright 2005 by The Associated Press. All Rights Reserved.)