National Grid Task -71 Operator Excavation and Backfilling Exam Test 2024\2025.
Soil class is type c and its the least stable
What type of soil class is used for national grid and how stable is it?
BEPM - Butane, Ethane, Propane, Methane
What are the natural gases?
for all excavations at a depth of 5 feet or more
When is shoring mandatory?
electric - powerlines, cables, conduit, and lighting cables
RED utility markings is
communication - alarm or signal lines, cables or conduits
ORANGE utility markings is
gas - oil, steam, petroleum, or gaseous materials
YELLOW utility markings is
sewer - sewers and drain lines
GREEN utility markings is
water - potable water
BLUE utility markings is
slurry lines - reclaimed water, irrigation or slurry lines
PURPLE utility markings is
temporary survey markings
PINK utility markings is
proposed excavation
WHITE utility markings is
white proposed excavation, pink temp survey and purple slurry, reclaimed and grey water and
radioactive lines
Which utility markings are seen but not as prominent?
on 6" lifts
when are pneumatic tamper and pavement breaker tamping foot used?
on 6" to 12" lifts
When are vibratory plate compactor and percussive whacker rammer used?
Tracing wire is present
Why should you use caution digging in area of plastic pipes?
811 for mark out
How do you notify utilities of the intent to excavate?
every 25 feet
When should you check for proper compaction in each trench?
Soil class is type c and its the least stable
What type of soil class is used for national grid and how stable is it?
BEPM - Butane, Ethane, Propane, Methane
What are the natural gases?
for all excavations at a depth of 5 feet or more
When is shoring mandatory?
electric - powerlines, cables, conduit, and lighting cables
RED utility markings is
communication - alarm or signal lines, cables or conduits
ORANGE utility markings is
gas - oil, steam, petroleum, or gaseous materials
YELLOW utility markings is
sewer - sewers and drain lines
GREEN utility markings is
water - potable water
BLUE utility markings is
slurry lines - reclaimed water, irrigation or slurry lines
PURPLE utility markings is
temporary survey markings
PINK utility markings is
proposed excavation
WHITE utility markings is
white proposed excavation, pink temp survey and purple slurry, reclaimed and grey water and
radioactive lines
Which utility markings are seen but not as prominent?
on 6" lifts
when are pneumatic tamper and pavement breaker tamping foot used?
on 6" to 12" lifts
When are vibratory plate compactor and percussive whacker rammer used?
Tracing wire is present
Why should you use caution digging in area of plastic pipes?
811 for mark out
How do you notify utilities of the intent to excavate?
every 25 feet
When should you check for proper compaction in each trench?
