Mid-Columbia Fire and Rescue Chief Bob Palmer says they have been unable to determine an accurate cause of Tuesday’s 20-acre fire west of The Dalles between Highway 30 and Interstate 84 near Pinewood Mobile Manor.  Palmer says there was a number of cigarette butts in the area, and it’s possible a smoker throwing one out from a car could have led to the fire, but it can’t be confirmed because there are so many of them.  Palmer adds it is unlikely anyone would have intentionally started the fire at that location because of its visibility.  The fire call came in at about 10:30 a.m. Tuesday.  Dallesport, Hood River, Oregon Department of Forestry, and U.S. Forest Service crews along with Klickitat County EMS were all assisting MCFR crews.