Pipeline Backfilling    

1.    Backfilling shall be carried out immediately after pipeline lowering in trench after inspection, so as to provide a natural anchorage for the pipeline, thus avoiding long exposure of coating to high temperature, damaging action of adverse weather conditions, sliding down of trench sides and pipeline movement in the trench.

2.    Backfill material shall not contain any extraneous material or hard lumps of soil which can damage pipeline or coating or leave the voids in backfilled trench.

3.    After placing of initial backfill, proper compaction shall be done.

4.    The surplus material shall be crowned (300 mm) directly over trench and adjacent excavated area on both side of trench.

5.    If trench are excavated in steep area where the slope is more than 10%, slope breakers shall be installed to prevent erosion of backfill.

6.    Stabilization of backfill shall be done in sandy area to have consolidated cover over the pipeline.