Brunot Island-Crescent Transmission Reliability Project

Duquesne Light is proposing to replace 106 existing transmission towers (“structures”), which were initially built approximately 100 years ago.

Not necessarily. The BI-Crescent Project proposes eliminating approximately 7 structures.

The new structures will be located along the same route of the existing structures. Specifically, the new structures will be placed along the 14.5 miles between the Brunot Island Substation to the Crescent Township substation.

Yes. In connection with the BI-Crescent Project and consistent with Pennsylvania Public Utility Commission (“PUC”) regulations, Duquesne Light conducted a siting study. The goal of the siting study was to select a reasonable route for the BI-Crescent Project and consider alternative routes for evaluation that are environmentally sound, feasible from an engineering and economic perspective, and compliant with applicable regulations. The existing route is the shortest and has the least impacts from an environmental, human/built, cultural, and engineering perspective.

If approved by the PUC the new structures will be “weathered” steel monopoles. The existing structures have a steel “lattice” configuration, which look like large silver steel triangles. The new structures are designed to fit into the natural environment. The new structure is a singular, reddish-brown, upright structure.

The new structures vary in height, but on average, the new structures will be approximately 155 feet high. The existing structures vary in height, but on average, are 93 feet high.

The BI-Crescent Project must be designed, maintained, and operated in accordance with the National Electric Safety Code, or “NESC.” Current NESC standards provide minimum wire clearances. In example: The NESC provides requirements for the clearance from wire to ground, which in turn increases the new structure height. Clearances required by the NESC from phase to phase also increases the new structure height. .

All NESC Rules that relate to 138kV voltage clearances as well as NESC loading and strength requirements would apply to the BI-Crescent Project.

No. The existing structures support two 138 kilovolt (“kV”) lines. The new structures will support the same voltages. The existing towers have one 138 kV line on each side of the structures. The new structures will have both 138 kV lines on the same side. When the Company originally submitted the BI-Crescent Project to the PUC, it proposed building the BI-Crescent Project to higher voltage standards. Based on customer feedback and generation changes in the region, Duquesne Light is submitting an amended proposal to the PUC. The amended proposal does not propose building to higher voltage standards. As mentioned above, the BI-Crescent Project does not change the existing 138kV voltage.

The new structures will be sturdier, safer, and will meet current NESC standards, which will allow the Company to deliver safe and reliable electric service to the region. Simply put, the existing transmission facilities are at or near the end of their useful lives.

There are several reasons Duquesne Light is not proposing underground transmission facilities for the BI-Crescent Project. For example, the outages involving the underground electric facilities take more time to resolve compared to overhead facilities. Additionally, underground cables last half as long as overhead facilities. In Western Pennsylvania where the terrain consists of steep slopes, hills, and rock, constructing an underground transmission line would significantly increase the project cost. Duquesne Light remains conscious of any increased costs to its customers, and has chosen not to underground the existing above-ground facilities as a safe, reliable, and cost-effective option for the benefit of its customers at large.

No. In fact, the exposure to electromagnetic fields (“EMFs”) remains at the same level at the edge of the right-of-way. The BI-Crescent Project has EMF levels that are below the allowable EMF exposure as outlined by the World Health Organization.

Duquesne Light must routinely inspect the growth around its facilities to make sure trees or brush are not interfering with its facilities. Maintaining the vegetation around the transmission facilities is important to prevent trees or other vegetation from causing power outages or reliability issues. To prevent regrowth, Duquesne Light uses herbicides approved by the U.S. Environmental Protection Agency and best industry practices.

Duquesne Light is happy to address any comments, questions, or concerns you may have about the BI-Crescent Project. Feel free to email BI-Crescent@duqlight.com. You can also visit the official filings on the PUC’s website, http://www.puc.state.pa.us/, by searching for Docket Number A-2019-3008589.