Water Well Journal

May 2016

Water Well Journal

Issue link: http://read.dmtmag.com/i/668983

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Page 51 of 77

T he possibilities of damaging underground utilities exist at every drilling site. Inadvertently severing an under- ground power line. Rupturing a natural gas line. Doing damage to underground utilities can result in costly consequences—disrupting essential services, requiring re- pairs, downtime, and potentially serious injuries or death. The number of incidents involving damage to underground utility lines submitted in 2014 reported in the Damage Infor- mation Reporting Tool (DIRT) was 273,599 for Canada and the United States. To prevent such incidents, it is critical to first understand the possible causes and industry practices in place. The most common causes for incidents resulting in underground utility damages are shown in Figure 1. The Occupational Safety and Health Administration has specific requirements (29 CFR 1926.651) designed to protect employees and prevent accidental damage to underground in- stallations. These include establishing the location of under- ground installations prior to beginning excavation activities. According to the DIRT Report (CGA 2014), calling the na- tional 811 call service before digging or drilling is the most important precaution professionals and homeowners can take. When an excavator or driller notifies a one-call center before digging—damage can be avoided more than 99% of the time! Underground utilities can be located by many methods— owner records, other sources of information, and utility locat- ing techniques. However, some methods can result in more uncertainty. The root cause category for damages in Figure 1 titled "Location Practices Not Sufficient" includes areas where no locating or marking of the utility was completed prior to excavation activities; areas where utility markings or locations were insufficient; the type of utility, its depth, or lack of records prevented locating the installation; and incorrect util- ity records and maps led to an incorrect location. Of the events that included utility damages and for which a locate request was made, the majority (68%) had visible but in- correct markings and 29% had markings that were not visible. The root cause category "Excavation Practices Not Suffi- cient" includes actions where clearances were not maintained while using power equipment; hand tools were not used where required; markings became deteriorated and not maintained; test holes were not used to verify exact location of buried lines; exposed utility lines were unsupported; and improper materials or compaction were used in backfilling (CGA 2014). Call Before You Dig The first step in preventing contact with underground util- ity lines is to call 811—the number the Federal Communica- tions Commission has designated as the national toll-free "Call Before You Dig" number for the United States. An 811 representative will take information about your project and notify appropriate utility companies to locate and mark buried lines they own at the location specified in the call ticket. The call must be placed at least 48 hours before work is scheduled to begin. Utility locations and markings are often made in utility easements only, not on private property. Therefore, if any drilling or other intrusive activities will be performed outside easements, underground lines will not be marked. There are also many other variables in locating and mark- ing underground utility lines. Among them: • Some utility owners feel a service line belongs to the property owner. • Power and communications cable and water/sewer lines serving buildings of educational institutions, government complexes, and office parks are on private property and are not covered by one-call. • One-call information does not provide depth, but rather a window of horizontal space where utilities are estimated to be buried. White-Lining the Dig Site White-lining is a best practice endorsed by the Common Ground Alliance (CGA 2015). Physical white-lining requires the excavator or drilling contractor to pre-mark the dig or drill site with white paint or an equivalent. While this practice is known to reduce damages, it may add costs to a job. The product Virtual WhiteLine™ is a re- SAFETY MATTERS PREVENTING DAMAGE TO UNDERGROUND UTILITIES You must have a plan so accidents are avoided and services are not disrupted. SAFETY continues on page 50 JEROME E. SPEAR In addition to power lines, there are phone lines, gas lines, water lines, and sewer lines running underground. Different detection techniques need to be used for different types of buried lines. waterwelljournal.com 48 May 2016 WWJ

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