Extensions of electric distribution lines made after June 5, 1968, which are necessary to furnish permanent electric service to new residential buildings and mobile homes, shall be made underground. The extensions of service shall be made by the utility in accordance with the provisions in these regulations. These regulations apply to: Extensions of electric distribution lines in subdivisions where primary, secondary, and service lines will be placed underground to provide permanent electric service to any number of residential buildings or mobile homes; and An extension to provide permanent electric service to a single residential building or to a mobile home. In this chapter, the following terms have the meanings indicated. Terms Defined. Applicant" means the developer, builder, property owner, or other person, partnership, association, corporation, or governmental agency applying for permanent electric service to new residential buildings or mobile homes. “Commission” means the Public Service Commission of Maryland. “Mobile home” means a dwelling unit constructed for permanent occupancy, which is: Designed for moving along roads and highways by towing with a truck or tractor; and Installed on a permanent foundation. “Person” has the meaning stated in Public Utilities Article, §1-101, Annotated Code of Maryland. “Public service company” has the meaning stated in Public Utilities Article, §1-101, Annotated Code of Maryland. “Residential building” means a structure enclosed within exterior walls or fire walls, built, erected, and framed of component structural parts and designed for single-family occupancy. “Subdivision” means a portion of real property: Which includes or otherwise designates lots or locations intended for residential buildings or mobile homes including “planned unit developments” or “new towns”; and For which a new electric distribution system is required in order to furnish electric service in it. “Underground electric distribution system” means that portion of an electric utility distribution plant necessary to furnish permanent underground service to all present and anticipated residential buildings and mobile homes in a subdivision. The system includes underground electric service lines as defined in §B(9) of this regulation. “Underground electric service line” means that portion of an electric utility distribution plant necessary to furnish permanent underground service from the lot line to a residential building or mobile home. “Utility” means an “electric company” stated in Public Utilities Article, §1-101, Annotated Code of Maryland. The utility shall construct, own, operate, and maintain an underground electric distribution system only along public streets, roads, and highways which the utility has the legal right to occupy, and on public lands and private property across which rights-of-way and easements satisfactory to the utility may be obtained without cost or condemnation, in reasonable time to meet service requirements. Rights-of-way and easements shall be cleared of trees, tree stumps, and other obstructions at no charge to the utility, and shall be graded to within 6 inches of final grade by the applicant before the utility will commence construction. The clearance and grading shall be maintained by the utility. If, subsequent to construction, the clearance or grade is changed in such a way as to require relocation of the underground facilities, the cost of the relocation shall be borne by the applicant or his successor. Upon receipt of a proper application, the utility shall install, own, and maintain an underground electric distribution system or underground electric service line with sufficient capacity and suitable material which, in its judgment, will assure that the applicant will receive safe, adequate, and reasonable electric service for the foreseeable future. If the underground electric distribution system is to be installed in a subdivision, the applicant shall furnish the utility as required, at no charge, property plats, utility plans, grading plans, roadway profiles, and other items showing details of proposed construction within the applicant's subdivision in reasonable time to allow the utility to engineer, design, and construct its facilities in a safe and efficient manner to meet service requirements and to comply with applicable laws, codes, and regulations. A charge may not be made by the utility for the underground installation, except in accordance with tariffs filed with the Commission and the following general guidelines: The service connection to the building normally will be at the corner of the building nearest the point at which the underground electric service line enters the property to be served. Each applicant will cooperate with the utility in an effort to keep the cost of construction and installation of the underground electric distribution system or service line as low as possible. Additional costs arising from failure of the applicant to cooperate with the utility, such as his making changes in grade or failing to maintain grade, shall be borne by the applicant. If an underground installation is to be constructed within a subdivision designed to include large open areas which would result in an abnormal increase in the investment per customer required to construct the underground distribution system, then the utility may refer the matter to the Commission for a ruling as to whether a charge should be assessed against the applicant, and the amount of the charge, if any. For underground electric distribution systems installed in subdivisions, the utility shall construct a connection from the boundary line of the applicant's subdivision to the utility's existing supply facilities, subject to the following provisions: The extension from the boundary line of the subdivision, for a maximum distance of 200 feet, shall be made underground, at the utility's expense; and If an extension in excess of 200 feet is required, then the extension over 200 feet shall be made underground in accordance with the regular extension of the utility on file with the Commission, subject to appeal to the Commission if this should appear to be impracticable. For underground electric service lines to new residential buildings or mobile homes for which §A of this regulation is not applicable, the utility shall construct an underground line from the lot line of applicant's property to the existing underground or overhead line on either side of the street or road in front of the lot, at no charge to the applicant. If there is no electric supply facility or overhead facilities of another public service company which may be jointly shared along the street or road at that location, then the utility shall construct an underground line to the nearest practicable existing electric supply facilities in accordance with the provisions of the regular extension rules in the tariff of the utility on file with the Commission. However, any charge or deposit to the applicant may not exceed the equivalent of $1 per foot of line extension not on applicant's property, subject to appeal to the Commission under Regulation .10, if this should appear to be impracticable. An electric company may not permit any person not a public service company to make attachment to any electric company existing overhead facilities for the purpose or intended purpose of providing overhead service to a customer to whom the electric company is required to provide underground service in accordance with the regulations of the Commission with respect to underground service. When, due to the manner in which a subdivision is developed, the utility is required to construct an underground electric distribution system through a section or sections of the subdivision where service will not be connected for at least 2 years, then the utility may require the applicant to make a reasonable deposit before construction is commenced. The deposit may be no more than the estimated installed cost of the underground distribution system less the estimated installed cost of transformers and meters. The deposit, without interest, shall be returned to the applicant on a proportional basis as each new customer in the subdivision completes his permanent service connection. Any portion of a deposit remaining unrefunded 10 years from the date the utility is first ready to render service from the extension will be retained by the utility and credited to an appropriate account. Each utility engaged in underground construction shall cooperate to the extent practicable in having information available for review by other utilities concerning applicants for new services. To the extent practicable, electric cables, communications cables, and gas pipes shall be installed in the same trench, due care being taken to conform to any applicable code and utility specification. Upon timely application, an electric company shall allow any person precluded from using overhead facilities as set forth in Regulation .06C of this chapter, joint use of its open trenches wherever reasonable and technically feasible in accordance with mutually agreeable terms and conditions. In unusual circumstances, when the application of these regulations appears impracticable or unjust to either party, or discriminatory to other customers, the utility or applicant may refer the matter to the Commission for modification of the regulations or for the approval of special conditions before commencing construction. Requests to the Commission for exemption from the requirements for underground installation of an electric distribution system or a service line shall be in writing and shall include the following: Description of the probable impact on the environment if the overhead line is constructed, including proposed overhead construction; Estimate of the installation cost of underground, by major elements; Estimated annual revenue from the proposed system or line; Number of customers to be served from the proposed system or line; and Property plat indicating the physical features, potential customers, and system or line layout (underground and overhead). Public Utilities Article, §§2-121 and 5-101, and Title 12, Subtitle 1, Annotated Code of Maryland Effective date: June 5, 1968 (Order No. 57282) Amended effective November 1, 1968 (Order No. 57413) Chapter revised effective September 1, 1971 (Order No. 59429) Chapter revised effective July 1, 1973 (Order No. 60316) Regulations .02D, E, .06C, and .08C adopted effective October 1, 1973 (Order No. 60391) Regulation .05 amended effective March 26, 1984 (11:6 Md. R. 557) Regulation .09 repealed effective August 21, 2023 (50:16 Md. R. 728)