Page 62 - CCGA Best Practices Version English

Practice Description: During long complex projects, the marks for
underground facilities may need to be in place far longer than the locating
method is durable. Paint, staking and other marking techniques last only as
long as the weather and other variables allow. When a mark is no longer
visible, but work continues around the facility, the excavator requests a
remark to ensure the protection of the facility.

4-17: Excavation Observer

Practice Statement: The excavator has an observer to assist the
equipment operator when operating excavation equipment around known
underground facilities.

Practice Description: The observer is a worker who is watching the
excavation activity to warn the equipment operator while excavating around
a utility to prevent damaging that buried facility. This is common practice
among excavators and large facility owners.

4-18: Excavation Tolerance Zone

Practice Statement: The excavator observes a tolerance zone which is
comprised of the width of 1 metre from the centreline of a located cable or
conduit and 1 metre from either side of the outside edge of the underground
facility on a horizontal plane. This practice is not intended to pre-empt any
existing provincial or federal requirements.
Practice Description: (See Practice Description for #4-19 following.)

4-19: Excavation within Tolerance Zone

Practice Statement: When excavation is to take place within the
specified tolerance zone, the excavator exercises such reasonable care
as may be necessary for the protection of any underground facility in or
near the excavation area. Methods to consider, based on certain climate
or geographical conditions, include: hand digging when practical, vacuum
excavation methods, pneumatic hand tools, other mechanical methods
with the approval of the owner, or other technical methods that may be
developed. Hand digging and non-invasive methods are not required for
pavement removal.

Practice Description: Safe, prudent, non-invasive methods that manually
expose a facility are considered “safe excavation practices”. Some guides for
excavation in the vicinity of utilities specifically allow for the use of power
excavating equipment for the removal of pavement and sidewalk but not
curbs or base materials. Differing geologic conditions and weather related
factors must be taken into consideration when using types of excavation
within the tolerance zone.

Canadian Common Ground Alliance
Best Practices Version 3.0 – October 2018
56