UFC 3-270-07
12 August 2002
2-2.4.2.6 Move unusable debris at least 9 meters (30 feet) off the MOS and stockpile
no higher than 0.9 meter (3 feet).
2-2.4.2.7 Standing water in the crater must be pumped out, if possible.
2-2.4.2.8 Any reinforcing material protruding from the original pavement must be cut off
and removed.
2-2.4.2.9 Clean an area 30 meters (100 feet) from the crater edge for assembling the
FOD cover, if possible. The mat assembly site should be no further than 0.8 kilometer
(0.5 mile) from the repaired crater. An area approximately 15 meters by 15 meters (50
feet by 50 feet) square is required for assembling the mat.
2-2.4.2.10 Backfill the crater with useable debris or a combination of debris and/or
crushed stone. Level this material to 406 millimeters (16 inches) below the original
pavement surface. This measurement is critical to ensure a flush repair.
2-2.4.2.11 Compact the debris backfill to a minimum 4 CBR.
2-2.4.2.12 Line the crater with an impervious membrane.
2-2.4.2.13 Place the first layer of sand-grid parallel to the centerline of the runway.
Place fill material or short U-shaped pickets in the corners of the grid and along the
sides to hold it in place.
2-2.4.2.14 Backfill the sand-grid using cohesionless material, if possible. Overfill the
grid by approximately 50 millimeters (2 inches).
2-2.4.2.15 Compact this first layer of fill material. Typically, two passes with a vibratory
roller are required for compaction.
2-2.4.2.16 After compaction, all excess material must be struck off level with the top of
the sand-grid. This is critical to ensure a flush repair meeting the RQC.
2-2.4.2.17 Place a membrane over the first layer of sand-grid.
2-2.4.2.18 Lay the second layer of sand-grid perpendicular to the first layer and the
runway centerline.
2-2.4.2.19 Backfill and overfill the sand-grid using cohesionless material, if possible.
2-2.4.2.20 Compact this layer of backfill. If the two sand-grids were installed and
compacted properly the sand-grid should not protrude above the pavement surface.
2-2.4.2.21 Grade off excess material so the repair is flush with the original pavement
surface.
2-8
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