WP1323 - Working Near Overhead and Underground Electric Lines

Electricity Entity Requirements:
Working Near Overhead and Underground Electric Lines

7.2.3       Heavy Machinery Operation Over Underground Electrical Assets
Where heavy “crawler” or “vibration” type machinery is operated over the top of cables, a
minimum cover of 450 mm to the cable protective cover must be maintained. Alternatively,
subject to a Certified Engineering Assessment, use load bearing protection whilst the machinery
is in operation.

7.2.4       Directional Boring Near Underground Electrical Assets
When boring parallel to cables, it is essential that trial holes are carefully dug using non
mechanical excavation (pot holing using hydrovac or hand tools) at regular intervals to prove
the actual location of the conduits/cables before using boring machinery. Where it is required to
bore across the line of cables/conduits, the actual location of the cables/conduits shall be
proven by non-mechanical excavation (pot holing using hydrovac or hand tools). A trench shall
be excavated 1 m from the side of the cables where the auger will approach to ensure a
minimum clearance of 500 mm from cables/conduits can be maintained.

7.2.5       Hydro Vac Operation
When operating hydro vac equipment to excavate in vicinity of underground electrical assets
(cables/conduits):
       Fitted with:
               nonconductive (neoprene rubber or equivalent) vacuum (suction) hose.
               oscillating nozzle on pressure wand with water pressure adjusted to not exceeding
                2000 psi.
       Maintain a minimum distance of 200 mm between end of pressure wand and underground
        electrical assets. DO NOT insert the pressure wand jet directly into subsoil.
       Ensure pressure wand is not directly aimed at underground electrical assets (cables /
        conduits).

7.3. Blasting
Explosives must not be used within 5 m of cables/conduits, unless an engineering report is
provided indicating that no damage will be sustained. Clearances shall be obtained from the
Electricity Entity for use of explosives in the vicinity of cables/conduits. Contact Electricity Entity
(General Enquiries phone number - refer page 3) for further advice.
The Electricity Entity will accept the level of 25 mm / sec as a peak component particle velocity
upper limit as defined in AS 2187.2 Appendix J for blasting operations in the vicinity of these
power lines.
Electric line insulators and conductors are particularly susceptible to damage from fly rock and
adequate control measure including the use of blast mats shall be used to manage this. Contact
Electricity Entity for consultation and application.

8.      REPORTING DAMAGE CAUSED TO OVERHEAD OR
        UNDERGROUND ELECTRIC LINES
Any damage caused to the Electricity Entity overhead electric lines, poles, stays, underground
cables, conduits and pipes must be reported no matter how insignificant the damage appears to
be. Even very minor damage to cable protective coverings can lead to eventual failure of cables
through corrosion of metal sheaths and moisture ingress.



Check this is the latest version before use.               Page 24of30                                        EGX WP1323 Ver 2
9 June 2015                                                                                               EE BS001405R107 Ver 2
                            Joint Reference Document between Energex and Ergon Energy
                    Energex Limited ABN 40 078 849 055  Ergon Energy Corporation Limited ABN 50 087 646 062