It has cut the number of park employees by more than half, from 4,507 in 1990 to 2,190 this year.
The process is controlled by the park employees and volunteers.
The park employee even thanked them for coming when they left.
The building now houses uniforms and other material for park employees.
The $33 million project, which began in the late 1970's, is halfway completed, park employees say.
"For the past 25 years there's been a downhill slide" in numbers of park employees, he said.
They are brought to a stop by two park employees.
Two park employees died in the explosion and resulting fire.
Of 33 park employees, at least three were killed and seven became refugees.
Two park employees have also died in accidents since 2001.