backfilling questions and accurate answers
1. Soil class is type c and
What type of soil class is used for national grid and
its the least stable
how stable is it?
2. BEPM - Butane,
What are the natural gases?
Ethane, Propane,
Methane
When is shoring mandatory?
3. for all excavations at a
depth of 5 feet or more
RED utility markings is
4. electric - powerlines,
cables, conduit, and
lighting cables
5. communication - alarm or signal ORANGE utility markings is
lines, cables or conduits
6. gas - oil, steam, YELLOW utility markings is
petroleum, or gaseous
materials
7. sewer - sewers and drain lines GREEN utility markings is
8. water - potable water BLUE utility markings is
9. slurry lines - reclaimed PURPLE utility markings is
water, ir- rigation or slurry
lines
10. temporary survey markings PINK utility markings is
11. proposed excavation WHITE utility markings is
12. white proposed excavation, pink Which utility markings are seen but not as
prominent?
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, National Grid Task #71 Operator excavation and
backfilling questions and accurate answers
temp survey and purple slurry,
reclaimed and grey water and
radioactive lines
13. on 6" lifts
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