Education & Resources

What is hydrovacing?

• Can safely replace hand-digging in the hand expose zone.
• Combines water pressure and a vacuum to excavate.
• Suits all sizes of projects.
• Fast, easy and safe when done properly.
• Works well during frozen ground conditions.
   

Requirements

• Use a wand tip and suction hose covered with Teflon® or rubber.
• Keep wand in motion at all times, with the wand tip at least 0.3 metres (one foot) from the line.
• The wand tip should have a three-jet tip or an agitating spinner assembly.
• Do not exceed pressures of 1,500 PSI or temperatures of 60ºC.
• Reduce pressure to finish exposing the gas line.
• Damage to the pipe or coating must be reported to ATCO Gas.
   

Hydrovac contractors

• Must carry a Material Safety Data Sheet (MSDS) for natural gas and be aware of emergency procedures.
• Cover and barricade all open holes and excavations.
• Responsible for the public’s safety until inspection and backfilling is complete.
• Responsible for major damage to a natural gas line – including costs of repair, gas loss, customer re-lights, and emergency response.
• Minor damage to the gas line coating will be repaired at no charge to the contractor.
• Must contact ATCO Gas immediately if damage occurs.

Only after hand exposing

• Hand expose the gas line first by shovel or hydrovac. 
• You must see the line to verify its location and depth.
• Only then can you use machines to excavate.

Safety musts

• Two workers should always be present – the machine operator and a spotter.
• Remove small layers of soil at a time.
• Dig parallel to the buried line. Stay at least 0.6 metres (2 feet) away from the line.
• Watch the excavation at all times for movement (cable contact), soil consistency (trench line) or foreign objects identifying underground facilities.

 Perpendicular drilling

• Expose the gas line by hand or hydrovac to create a day-lighted area.
• This area should extend at least 0.3 metres (one foot) on all sides around and below the pipe – one metre (three feet) is better.
• The drill path must cross under the pipe in this day-lighted area.
• Keep a close watch on the area below the pipe to ensure the drill-head does not hit the gas line.
• Watch during both the initial push and the pull-back.
• Never assume the gas line will be at the same depth on either side of the day-lighted area.

Parallel drilling

• If drilling within one metre (three feet) of the outside edges of the natural gas locate marks, you must hand expose.
• Hand shovel or hydrovac a number of points along the gas line.
• Number of day-lighted points depends on the drill path and depth of the gas line.
• At minimum, points must be exposed every 30 metres (98 feet) along the line.
• For shorter jobs, points must be exposed more closely.

What are temporary support systems?

• Installed before excavating below a natural gas line.
• Also used during the backfill.
• Prevent gas lines from sagging, bending or deflecting.
• Usually made of steel or wood.

Is it always required?

• Depends on the length of the gas line.
• Contact us  
• We will walk you through the requirements, methods and materials.

An ATCO Gas representative must inspect your temporary support systems.

Call Us

• Before you backfill around a natural gas line.
• If you discover a natural gas line with less than 0.6 metres (two feet) of cover.

Other requirements

• Compact the fill under the gas line to provide support.
• Do not interfere with gas lines.
• Do not add to the depth of cover without ATCO’s permission.
• Use clean, lump-free material to cover the line.
• Do not place frozen dirt on the line.