MCPHERSON, Kan. - An oil refinery's $555 million expansion project is proving to be a boost to McPherson's economy. The National Cooperative Refinery Association oil refinery is replacing its coker, which converts some residual oil into higher-value products. The project has brought cranes, one as high as 530 feet tall, to the city's skyline. NCRA spokesman Vince Bengston says the project should conclude by late September. McPherson Chamber of Commerce executive director Jennifer Burch says the project brought more than 1,000 people to McPherson, which is also benefiting surrounding communities because there isn't enough housing in McPherson. The Hutchinson News reports (http://bit.ly/1qbMJ4a ) that later this year, NCRA plans to shut down the refinery to clean it, which Burch said will bring another 2,500 people to the area.