INTRODUCTION
I. SYSTEM WIDE
II. BUTTERFLY ENHANCEMENT PROJECT


INTRODUCTION

The Potomac Electric Power Company (PEPCO) is headquartered in the Nation's Capital, and serves the electrical energy needs of Washington, D. C. and the surrounding metropolitan area. The service area is supplied through a network of transmission lines on 330 miles of rights-of-way, which covers approximately 10,000 acres. Pepco's overhead transmission line rights-of-way are purchased in "fee simple" with the exception of small portion that transverses state and federal property, where easements are obtained.

One of these rights-of-way passes through the U. S. Department of the Interior's, U. S. Fish and Wildlife Service's, Patuxent Wildlife Research Center. The PWRC is world renowned for their extensive research and educational programs. Part of the PWRC is open to the public at the multi-million dollar Visitors Center. Pepco contributed to the success of this facility and there is a field observation area that depicts an optimum electric utility corridor.

For decades Pepco and PWRC has had a very successful partnership managing the vegetation in a fashion consistent with the mission of the wildlife center. The program that was established on the PWRC became the primary method of vegetation control throughout the Pepco system.

Pepco's Transmission Strategic Business Unit will continue to incorporate and be proactive in environmental stewardship as part of the integrated vegetation management program in maintaining the transmission line rights-of-way. These efforts are in joint sponsorship with Pepco's Natural Resource Management Department.

One of Pepco's environmental stewardship initiatives is the Butterfly Enhancement Project.

I. SYSTEM WIDE

PEPCO'S INTEGRATED VEGETATION MANAGEMENT PROGRAM

Potomac Electric Power Company's rights-of-way (ROW'S) are essential for the safe and reliable transmission of electricity. Tall growing trees, commonly referred to as undesirables, naturally invade and can eventually dominate ROW'S, posing a threat to electric service reliability and safety. The principal vegetation management objective is to remove these undesirable plants and promote the growth of low-growing, relatively stable plant communities. Desirable plants are compatible with electric system reliability (needing relatively little maintenance over the life of the ROW) and, we believe, are aesthetically appealing and beneficial to wildlife.

Pepco utilizes various management tools to control and maintain the vegetation on the rights-of-way. Many factors affect the prescriptive analysis for the care taking of 10,000 acres of transmission line right-of-way. The following are the primary programs used to monitor and maintain the rights-of-way throughout the Pepco overhead transmission system:

AERIAL INSPECTION - A contractor patrols the designated transmission and sub-transmission (circuits) by air. The patrol occurs twice a year, during the spring and winter. The contractor inspects the facility for unauthorized activity, erosion and vegetation problems, as well as for broken insulators and wires.

BARRICADE AND DEBRIS - This program is used for removing illegally dumped debris from Company property, the construction of barricades to prevent vehicles from trespassing onto Company property and soil restoration to prevent erosion.

BRUSH CONTROL - The primary purpose of this program is to control undesirable trees with herbicide application. In addition to the herbicide work there will be other vegetation control work, both manual and mechanical. This also includes some tree trimming and other miscellaneous work.

CONFLICT TREE - This work is primarily the trimming and removal of those trees which are outside the bounds of the transmission line rights-of-way that, if the tree fell toward the transmission facilities within the next 10 years, could damage those facilities or cause an interruption in service.

TRACTOR MOWING - In this program, the contractor mows the grass and weeds on Pepco's rights-of-way. This is usually in the more urban areas or where housing developments are adjacent to the rights-of-ways. The work is typically performed with a farm tractor pulling a "bush-hog" mower.

THE 230,000 VOLT OUTAGE

During 1998, we experienced an electrical outage on one of the 230kV circuits due to a single tree that grew into the wires. Six other trees were found burning in the wires. After a system wide aerial and ground inspection, approximately 350 trees were considered too close to the wires and had to be removed before the next growing season. The entire vegetation management program was re-evaluated and we concluded that more intensive (control of the vegetation) ROW maintenance practices must be achieved. The vegetation density of undesirable species was too high. The test plots revealed in many locations 25,000 to 30,000 stems per acre. A reasonable manageable level of 2,000 stems per acre is acceptable. The heights of a majority of the undesirable species were over 10 feet, upwards to 35 feet. The dense, high growing vegetation could fuel an out of control fire resulting in damage to the towers and wires. Pepco would be unable to transmit electricity and a major power outage would occur.

In order to successfully recapture our ROW'S, three goals must be achieved:

1) Reduce the stem density of undesirable species and undergrowth, which makes our ROW'S inaccessible and more costly to maintain.

2) Reduce the height of all species to less than 10 feet, thereby increasing reliability.

3) Extend all management practices to the edge of our property, thereby recapturing the full extent of the ROW and reducing the encroachments of vegetation onto our property.

To reach our goals, we developed the program of "meadow management - a low profile shrub/scrub plant community." The initial phase of this program is to mow, a one-time process, all vegetation and treat the area with a herbicide to limit the undesirable type of woody species from resprouting. The rights-of-way are then maintained on a four-year cycle. Henceforth, only a selective basal application of herbicide will be used to treat the undesirable species and any undesirable species over ten feet will be removed. Thus, creating a low profile shrub/scrub plant community that is beneficial to wildlife habitat and compatible with providing safe and reliable electric service.

This "meadow management" approach was presented to a jointly sponsored Edison Electric Institute and U.S. Fish & Wildlife Service seminar that was held at the Patuxent Wildlife Research Center on October 26, 1998. Participants were from EEI, BGE, Connectiv, AEP, Fish and Wildlife Service-National Conservation Training Center, PWRC and Pepco.

The development of the Integrated Vegetation Management Plan (IVMP) is critical to the success of the Company's goal in providing safe and reliable electric service. The IVMP is a dynamic management tool. Over the years, we have maintained our ROW'S consistent with corporate direction. The rights-of-way had established a mini-forest underneath the high voltage power lines. This management practice had to change.

II.BUTTERFLY ENCHANCEMENT PROJECT

In western Montgomery County Pepco is enhancing an area on the Dickerson to Potomac River 230kv transmission line right-of-way, to provide for butterfly habitat. Transmission line rights-of-way consist of many ecosystems as they transverse across the country.

Butterfly populations are an integral part of this complex community in that they are the great pollinators of flowers and provide food for wildlife and add to the beauty of nature's surroundings. In developing the Butterfly Enhancement Project (BEP), Pepco's meadow management program is to remove all of the trees under the transmission lines in selected areas, bushhog everything near ground level and use selective herbicides to prevent rapid regeneration of all woody perennials the first year. This permits the dormant annual and perennial seeds of grasses and herbaceous plant material to germinate and grow. The second year, and thereafter, all woody perennial seedlings of taller growing species are spot treated with a selective herbicide. The low growing wildlife habitat can be reestablished and maintained in this manner.

The BEP is a joint partnership with the Washington Area Butterfly Club (Pat Durkin), the International Butterfly Breeders Association (Jay McRoberts), Maryland-National Capital Park and Planning Commission (Dennis Gibbs) and Pepco.

We will selectively introduce as many native butterfly nectar and larva host plants as possible, along with the naturally occurring herbaceous vegetation. One area will be maintained as a control section and allow only the natural low growing vegetation to germinate. There is approximately six acres on the right-of-way that was timbered, mowed and treated in the spring of 1999 (See attached drawing). Only a partial growing season elapsed from the time of mowing and treatment, thus germination did not reach its full extent. However, the herbaceous growth, even with the severe drought, was impressive.

Jay McRoberts said, "Pepco's approach to these scrublands is impressively butterfly friendly, and might be something IBBA could advocate with other power companies once we become more informed of the details." Pat Durkin of the WABC has already begun contacting other electric utility companies in the pursuit additional butterfly habitat.

Pepco continues to strive to be good stewards of the environment. Several other initiatives the company has embarked on are reparian enhancement, bayscapes and raingardens, bog conservation/ preservation, wild turkey habitat enhancement and seeking recognition in a program called Project Habitat by American Cyanamid (co-sponsor is Butterfly Lovers International).

---

The pictures shown above were taken on 8/21 showing the first growing season and the success of our meadow management/butterfly project on the Dickerson-Pleasant View 230kv right-of-way. Half of this right-of-way is shared with Allegeny Power's 500kv (note their treed section of the r/w).

A multitude of wildflowers attracting the butterflies and other insects is developing an ecosystem that was prevented from being established, because of competition from the previous tree. This area was also shown during the Wildlife Habitat Council's site inspection for Pepco's certification.

Stephen M. Genua

STAFF FORESTER
TRANSMISSION LINE RIGHT-OF-WAY
INTEGRATED VEGETATION MANAGEMENT PROGRAMS

POTOMAC ELECTRIC POWER COMPANY
1900 PENNSYVANIA AVE., N.W.
WASHINGTON, D. C. 20068

G;wabc/amg.3/23/00