Page 22 - Texas811

From the Locator’s
By Bob Nighwonger DUtility Training Academy
Responding to Emergency Excavations and Repair
uring the course of any given day, many line locating technicians are responding to emergency 811 excavation
notifications. Many of these emergency excavation requests involve a service outage, broken poles or leaking product which can create hazardous scenarios and need emergency excavation to take place in order to repair and make it safe.
During my years as a full time utility locator, I gained a lot of personal experience responding to hundreds of these emergency excavations involving repair of our aging infrastructure. Here are a few tips for line locators and
any other responders to these types of emergencies.
First and foremost you should definitely know what emergency scenario you are responding to and the potential hazards on the excavation and repair site.
Responding to Damaged or Leaking Natural Gas Lines
These were the types of emergencies that worried me the most. I once heard a horror story about a vehicle pulling up to a gas leak and igniting the blast and killing the driver. I knew that I never wanted to be the person who brought the ignition source to the
fuel source. If dealing with natural
gas or other hazardous material lines, determine wind direction and park upwind. Remember that natural gas
is lighter than air and can collect in covered spaces and mix with air at just the right level to make it very explosive. If a buried pipe is leaking or the pipe was struck during directional drilling operations, the gas can migrate through the soil into a nearby basement or sewer pipes which lead to houses or buildings where the gas may find an ignition source. Do not park over any valve
lids or manhole covers. The valve you accidently park on may be needed to isolate the flow of gas from the leaking pipe. Manhole covers are often removed to vent out any natural gas that may have seeped into the sewer system.
If the fire or police department is on site, contact the incident command and let them know who you are and why you are there. Do not enter
the controlled site until you obtain permission and are informed the area is now safe for you to proceed. Line locating equipment is not intrinsically safe. Electrical arcs could occur
when applying or adjusting the direct connection leads.
Responding to Emergencies involving Broken Power Poles and Downed Power Lines
These types of emergencies are often associated with storm damage or a car accident. During a heavy ice storm, I received an emergency call-out around 1:30 in the morning. The emergency call was made by a power company crew that needed to replace a broken pole hit by a car. The broken pole was located in front of a bank. I had a power line and telephone cable coming down and had to spot them before the pole could be replaced.
I have always had respect for electricity and I was determined not to touch anything metal on site. Since the pole had already been broken and ice continued to build on the power lines, the crew supported the pole with their bucket truck. I decided to get away from that hazardous area and apply my locate signal on the cables from the bank and trace the lines back to the pole. I chose to apply my locate signal indirect to each line because I didn’t want to directly connect my signal transmitter to the meter, transformer
or shield of the phone cable just in
case a short occurred when the pole was broken which may have made the grounding systems of both the electric and telephone systems electrified. As I traced the lines back to the broken pole, I kept my eyes open and approached from the opposite direction that the pole was leaning. I do remember thinking that my hard hat was probably not going to do much good if the pole came down on my head, but it’s all I had.
Another tip for this type of scenario
is to not park near broken poles or downed power lines, or any other overhead lines in the general area. The pole was installed to support the weight of the lines and now the lines are supporting the pole. This is sure to put a lot of extra stress on the entire overhead system in the area that could break additional poles and lines in the area, well after the initial damage.
Responding to Emergency Locates involving Damaged Water Lines
Water leaks are very common on both small and large scale occurrences. There is a difference between a trickle leak and a full on ruptured pipe. Some water pipe ruptures are powerful enough to wash out the soil beneath the grass and roadways and could result
in an unexpected sink hole on site. Anything on the roadway, including people and equipment, could end up at the bottom of the hole if they’re not extra careful.
When responding to emergency excavation notifications for repair and restoration of both pipeline and utility outages and leaks, it is good to be paranoid. In some cases, you may be heading directly into harm’s way, so take your time to evaluate the site and make a plan of approach.
20 • Texas811 2024, Issue 3