6044580 REPAIR AVIATION CONCRETE APRON BASE ASTORIA

SCOPE: Project will correct aviation pavement and sub-grade failures as identified by recent pavement analysis sub-grade study (PSN: 5665535). Study identified sections to be removed and sub-grade replaced to correct settling issues and to prevent further degradation and failure of the aviation apron system. Apron drainage as well as sub-grade drainage will need to be incorporated into the design to increase effectiveness of repairs and mitigate future failures of new and adjacent apron panels. JUSTIFICATION: Protection of operational assets. The apron is critical for operations. In 2012, a $1.2M maintenance project was completed to address runway pavement failures that impacted operational use. The damage was significant and ranged from divided slabs and joints, spalled concrete, sink holes and other depressions caused by poor soil conditions. Airframes transiting across the apron had to exercise extreme caution to protect the aircraft from potholes, cracks, and other pavement deficiencies. The maintenance project resolved these symptoms and restored partial operational use. However, root causes of the issues were from sub-grade failures that can only be addressed with full replacement of the sub-grade and apron concrete panels. Continued deterioration of the sub-grade after the 2012 maintenance project has required loading restrictions on portions of apron that present potential damage to airframes. IMPACT OF DENIAL: Sector Columbia River will not be able to operate its aircraft without potentially causing damage to its assets. Foreign Object Damage (FOD), potholes, cracks, and standing water may cause damage and increase required maintenance on transiting aircrafts, as well as continue to damage the apron. Furthermore, loose grout and spalled concrete present significant hazards to personnel should they be dislodged and thrown by operating airframes.