The maximum dry unit weightobtained from a standard compaction test on a silty sand forest road subgrade soil is 110 lb/ft^3. The corresponding optimum water content is 26%.The compaction specifications call for compaction to 90% or greater of the maximum dry unit weight by the standard compaction test, and a water content of 2% less than the optimum water content. If the existing natural water content is 17%, how much water, in gallons, must be added per cubic yard of compacted soil to meet the specification?