What was that in the siding at Hito?

SP 3383 W. the Valley Flyer at the south end of Oregon City, Oregon - April 1994

SP's peddler freight to Eugene switches cars on a gratefully clear early Spring day in 1994. There is a lot of notable detail in this photograph. From left;  James River Paper Mill in West Linn, an open time switch box next to the switch stand, the Conde B. McCollough cast concrete bridge over the Willamette, Mt. St. Helens, Smurfit paper mill,  one rather decrepit SP GP-9 with improvised nose lettering, and some very muddy ballast.