Early in 1918, Yamhill County requested that the concrete pavement laid in 1917 be continued to a total length of four miles, and offered to pay for all grading necessary in connection therewith. This request was granted by the Highway Commission and in the early spring, construction was started on the additional 2.2 miles.
The type of pavement laid on this section was the same as that laid in 1917, except that crushed rock aggregate was used instead of gravel, and the mix was reduced to 1 : 2 : 31⁄2.
STATE OWNED PAVING PLANT IN OPERATION NEAR SHERIDAN IN YAMHILL COUNTY. ON THE YAMHILL NESTUCCA HIGHWAY
The coarse aggregate consisted of crushed stone ranging from 1⁄4 inch to 21⁄2 inches. For the fine aggregate, both Columbia River and Willamette River sand was used. The stone was crushed from a quarry operated by the State on Deer Creek which was near the center of the job and consisted of an altered basalt of rather coarse texture. The quality of this stone is not equal to the true basalt; but tests made by the Oregon Agricultural College showed that it was of good quality. The average haul on this material was .6 of a mile.
Crushing was begun early in March and 1200 cubic yards of material stored in a stock pile which was rehandled later by means of an automatic loader purchased by the State Highway Department for this class of work. The output of the crusher was insufficient to keep the mixer running and by means of this stock pile it was possible to keep the material coming on to the road steadily and finish the job in a minimum length of time and with the least inconvenience to traffic.
In this connection the experience on this job shows the advisability of using a stock pile of material to draw from in case of emergencies. When this is done the work is allowed to go ahead steadily, although a breakdown at the crusher may occur. The saving made by a steady run more than offsets the cost of rehandling the material, which is done very reasonably by the use of machinery.
The sand was shipped to Ballston and Sheridan by railroad, approximately equal amounts being shipped to both places and was so divided as to get a minimum length of haul on this material. The average haul was 3.5 miles. At Ballston the sand was unloaded from the cars into bunkers, which dumped directly into trucks, while at Sheridan no bunkers were available and the material was unloaded on the ground and rehandled by means of an automatic loader. No delay was caused by car shortage as we used our stock pile at Sheridan in emergencies. All the material was hauled and handled by means of trucks, two of which belonged to the State Highway Department, others working on a yardage basis.