Lead Sheathing of Cables
A recent Wall Street Journal investigation found more than 2,000 lead-sheathed telecom and power cables across the nation, and AT&T has confirmed that roughly 200,000 miles of their copper wires are sheathed in lead. Many of these cables are underground, raising concerns about lead being released into water and surface soil. The article focused on legacy lead covered copper cable infrastructure in the telecom industry, but the investigation raised questions about such infrastructure in other sectors, particularly electric power.
Telecommunications is not the only network infrastructure with lead-covered cables. Electric power cables installed from the 1800s into the 1960s were often sheathed in lead and buried underground, underwater, and in certain cases, on overhead pole lines. Lead-sheathed cables were also used for communication, power, and signaling by railroads. Paper-insulated lead-covered (PILC) cables have been used in medium and high voltage power distribution in the United States since the late 1800s. PILC cable is still manufactured by companies like Okonite, but today’s PILC cables are further protected with a polyethylene sheath to protect the cable from the environment, and the environment from the cable.
While many of the older PILC cables are being replaced as they reach their lifespan – generally 30 to 50 years – some electric cables have been in use for more than 90 years. It is difficult to estimate how many miles of such electric power cables exist without reviewing cable records at the local level for every transmission and distribution utility. Reports submitted by electric utilities such as FERC Form 1 provide circuit-miles for different voltages, but they do not cover aerial conductor or underground cable type, size, or insulation.
Concerns with Lead-Sheathed Cables
Not all PILC cables are dangerous to the environment. Some PILC cables are protected by a polyethylene jacket and are encased in underground ducts. Efforts to remove these cables may be more harmful than leaving them in place. Many utility companies choose to leave cable no longer needed or retired from service dead and abandoned (D&A) to avoid the cost of remediation if it is determined that leaving the cables in place does not risk contamination or environmental damage.
The EPA has addressed lead in soils and water as part of the EPA Strategy to Reduce Lead Exposures and Disparities in U.S. Communities and pursuant to the response authorities in section 104 of the Comprehensive Environmental Response, Compensation and Liability Act (CERLCLA) and in section 1431 of the Safe Drinking Water Act (SDWA). In the case of PILC cables, however, this process is time consuming and complicated. Older conduit and duct systems may have shifted or been crushed making removal difficult if not impossible. Replacement cables may have larger diameters than PILC cables due to the need to increase system capacity, rendering existing ducts unusable.
It’s important to understand that electric power transmission and distribution cable networks have not experienced the technological transformation that telecommunications networks experienced when they moved from copper to optical fiber. Often, older power cables are still used and useful, and they have not been rendered obsolete nearly to the extent of copper communications cable. Furthermore, the critical nature of electric power, concerns about aging electric infrastructure, and a societal imperative for “grid modernization” have created an environment where regulators have encouraged electric utilities to make reasonable investments to upgrade their physical plant. So, while there is a concern about this type of cable generally, and the telecommunications variety has been rendered obsolete and simply abandoned, its electric power brethren is being steadily, if slowly, replaced.
Lead-Based Infrastructure Remediation and Removal Complications
OSHA requires companies that remove lead-sheathed cable use extensive safety protocols to keep workers safe [OSHA 1910.1025]. Whether in an enclosed environment such as a manhole or underground vault, or on poles, proper ventilation and encapsulation of materials containing lead are required. Workers must wear appropriate personal protective equipment, and air monitoring may be required. Today, specialized techniques to remove cables from ducts have been developed by a number of companies and cables previously considered infeasible to remove are being reclaimed and recycled.
Removal of underground cable infrastructure from manholes generally involve environmental remediation. Manholes collect water, and that water often contains traces of oils, lead, and PCBs. The water must be pumped out of the manholes, tested for hazardous materials and contaminants, and treated before it can be discharged to municipal treatment systems.
Older PILC cables in manholes often had asbestos fireproofing wrapped around the splices and the cables up to the entry and exit ducts. Asbestos is carcinogenic, so workers must wear appropriate protective gear while removing the asbestos fireproofing [OSHA 1910.1001]. The asbestos must be safely transported to an approved disposal site.
Once the work area is safe from asbestos and environmental hazards, a cable removal team can begin work. If the cable was in use, it must be de-energized and grounded for electrical safety. The removal team must follow lockout-tagout procedures to ensure personnel safety, with the individual responsible for the work holding all safety tags and ensuring every member of the work team is accounted for and no one is exposed to hazards.
PILC cable that is removed from service, cut, and scrapped, is likely sent to salvage operations for the value of the copper conductor or steel armoring in the case of submarine cable. The lead sheath is either safely recycled or sent to a hazardous material landfill.
Starting the Lead Remediation Process
Programmatically and systematically removing PILC cables is a long-term commitment. A complete inventory of your cable network is required, including which cables are still in use, which ones are dead and abandoned, and which ones pose the greatest risk to the environment and local communities. Failure frequency data across installations and cable types, or those at the end of their life, or those identified as creating the highest level of actual exposure to a community, are examples of the kind of risk assessments that support such a program.
In a constructive regulatory environment, long-duration capital programs will eventually drive replacement of aged cable irrespective of construction and configuration, but this can take decades to complete. The EPA is encouraging utilities to remove old PILC cables as soon as possible, but safely removing lead-covered cables that may still be in use is both expensive and difficult, requiring careful planning and execution. Tangibl has extensive experience with cable replacement programs of all types, including understanding the constructability issues associated with capacity upgrades, reliability improvements, and asset management generally. The right consulting partner can help you develop the best, most cost-effective plan to implement a PILC cable replacement program.
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The EPA has encouraged utility companies to remove Paper-insulated lead-covered (PILC) cables from the ground as soon as possible, but this process is complicated, time consuming, and often very expensive. When a company develops a PILC cable remediation plan, they need to evaluate their entire cable network, complete a risk assessment, and develop a holistic remediation plan for the entire network. Not all cables need to be removed, and sometimes leaving cables in place is the safest course of action. You need an expert team to work collaboratively and create the optimal remediation plan.
If you need to assess your PILC cable infrastructure and develop a comprehensive plan for cable removal, contact Tangibl’s Utility Engineering and Consulting team to learn how we can help.