Power Generation, Transmission, and Use

Markets, Regulation, and Oversight

Impacts of Power Generation and Transmission

Looking Ahead


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Maryland Power Plants and the Environment (CEIR-18)

Chapter 1 Background

The Maryland Department of Natural Resources (DNR) Power Plant Research Program (PPRP) evaluates how the design, construction, and operation of power plants and transmission lines impact Maryland's environmental, socioeconomic, and cultural resources. PPRP's legislative mandate seeks to ensure that the citizens of Maryland can continue to enjoy reliable electricity supplies at a reasonable cost while minimizing impacts to Maryland's resources. The program plays a key role in the licensing process for power plants and transmission lines by coordinating the State agencies' review of new or modified facilities and developing recommendations for license conditions.

PPRP is directed by the Maryland Power Plant Siting Act to prepare a biennial Cumulative Environmental Impact Report (CEIR). The intent of the CEIR is to assemble and summarize information regarding the impacts of electric power generation and transmission on Maryland's natural resources, cultural foundation, and economic situation. A listing of key PPRP projects and reports, as well as a complete Program bibliography, is available at

This eighteenth edition of CEIR (CEIR-18) is divided into chapters as follows:

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The Role of PPRP

The Maryland legislature passed the Power Plant Siting Act in 1971 as a result of extensive public debate over the potential effects of the Calvert Cliffs Nuclear Power Plant, which was in the approval and design stage, and the legislature’s desire that the State of Maryland play a significant role in the decision-making process. At that time, Calvert Cliffs was a source of concern mainly due to its once-through cooling system, designed to withdraw up to 3.5 billion gallons of water per day from the Chesapeake Bay and then discharge it back into the Bay with an increase in temperature of up to 12°F. This and other issues prompted the creation of PPRP to ensure a comprehensive, objective evaluation based on sound science to investigate environmental and economic issues.

Today, PPRP continues this role by coordinating the comprehensive review of proposals for the construction or modification of power generation and transmission facilities and by developing technically based licensing recommendations for submission to the Maryland Public Service Commission (PSC). Consistent with the original statute, PPRP also conducts research on power plant impacts to Maryland’s natural resources, including the Chesapeake Bay. In addition to surface water concerns, PPRP evaluates impacts to Maryland’s ground water, air, land, and socioeconomics for proposed power facilities and transmission lines, both for new installations and for modifications to existing structures.

Power Plant and Transmission Line Licensing

The PSC is the regulating entity whose jurisdiction includes licensing power generating facilities and overhead transmission lines greater than 69 kilovolts (kV) within the state. The PSC is an independent commission created by the State legislature with commissioners appointed by the Governor for set terms.

An electric company that is planning to construct or modify a generating facility or a transmission line must receive a permit, called a Certificate of Public Convenience and Necessity (CPCN) from the PSC prior to the start of construction. The approved CPCN constitutes permission to construct the facility and incorporates several, but not all, additional permits required prior to construction, such as air quality and water appropriation (see Appendix A).

Applications for a CPCN are reviewed by the PSC, or a delegated Public Utility Law Judge, in a formal adjudicatory process that includes written and oral testimony, cross examination, and the opportunity for full public participation. Parties to a CPCN licensing case include the applicant, the PSC Staff, the Office of People’s Counsel (acting on behalf of the Maryland ratepayers), and PPRP (acting on behalf of DNR and six other State agencies). Other groups, such as federal agencies and private environmental organizations, as well as individuals with a specified interest, also may have a right to participate as intervenors in these hearings. The broad authority of the PSC allows for the comprehensive review of all pertinent issues and was designed in 1971 to be a "one-stop shop" for power plant licensing.

The CPCN licensing process provides an opportunity for the State to examine all of the significant aspects and impacts of a proposed power facility or transmission line, including the cumulative effects of interrelations between various impacts. This is a unique process within the State’s regulatory framework. The CPCN mechanism recognizes that electricity is a vital public need, but its generation and transport can result in impacts to the state’s natural, social, and cultural resources. A distinguishing feature of PPRP’s role in the CPCN process is the high degree of interagency coordination involved. PPRP coordinates the project review and consolidates comments from the Departments of Natural Resources, Environment, Agriculture, Commerce, Planning, and Transportation, and the Maryland Energy Administration. PPRP then develops a consolidated set of scientifically supported recommended license conditions, unique to each facility’s CPCN, and submits these recommendations to the PSC on behalf of the State agencies. In many instances, conditions go beyond regulatory requirements to incorporate creative measures for mitigating potential facility impacts, often as stipulations agreed to by the applicant and other parties to the case prior to the conclusion of the adjudicatory process.

In the case of multiple facilities proposed in close proximity to each other or to existing plants, or for transmission lines that span multiple regions and resource areas, PPRP includes cumulative impacts within the consolidated review process. In such a case, impacts to air, water, terrestrial, socioeconomic, and other resources are evaluated and compared to any identified thresholds of acceptability. Additionally, the cumulative analysis identifies any licensing conditions needed to address cumulative impacts.

Figure 1-1 illustrates the elements of the CPCN licensing process. The primary steps in the CPCN licensing process are described below.

Figure 1-1 The CPCN Licensing Process

The CPCN Licensing Process

Pre-application. While there are no required pre-CPCN application procedures, PPRP encourages prospective applicants to meet with PPRP staff to identify potential issues of concern with the proposed generation or transmission project and to determine whether and how all relevant concerns will be addressed. This process provides an opportunity for the applicant to become familiar with the PSC regulations and procedures. By the time the applicant files for a CPCN, there usually has been a significant amount of dialogue and, often, the applicant has determined that there is a high likelihood that the proposed facility can obtain a CPCN, subject to the license conditions adopted by the PSC. Through a diligent and thorough pre-application process, a prospective developer can limit the risk of submitting an unsuccessful CPCN application by making changes during the preliminary design to minimize certain impacts.

Application. PSC regulations require the CPCN applicant to summarize the proposed project and its potential environmental, social, cultural, and economic impacts. The application is often accompanied by an environmental review document that presents the applicant’s supporting environmental and socioeconomic studies. Once the applicant has submitted a CPCN application to the PSC, PPRP, in coordination with other State agencies, evaluates the potential impacts of the proposed project on Maryland’s resources, including water (surface and ground water), air, land, ecology, and socioeconomics, including visual and noise-related impacts. In the case of transmission line projects, the need for the project is evaluated and a review of alternative routes is conducted as part of the review process. In the case of generation there is no need or justification requirement; because Maryland is a market-based state, applicants seeking a CPCN for a generating unit do not have to demonstrate that the State has a need for the power.

PSC Process and PPRP Review. The PSC typically assigns a Public Utility Law Judge (PULJ) to the licensing case at a preliminary administrative meeting after an application for a CPCN has been received. The PULJ then schedules a pre-hearing conference to establish an overall procedural schedule, including dates for evidentiary and public hearings. The adjudicatory process commences with a discovery phase, and proceeds to the filing of direct testimony from the applicant summarizing the impact analyses that have been completed and providing the basis for the applicant’s request for a CPCN. During the PSC evidentiary hearing, all the parties to the proceeding may actively participate and file their findings as formal testimony. PPRP and any other parties that have intervened in the process may cross examine applicant testimony and present their own analyses in direct testimony. PPRP’s testimony, presented on behalf of the various State agencies, typically includes initial recommended license conditions along with justifying analyses (in the form of testimony and an independent environmental review document), which can be subject to vigorous cross examination by all parties. Other intervening parties can prepare direct testimony and present their opinions and arguments in turn, and are also subject to cross examination. The PULJ also presides over public hearings to accept comments on a project from the general public.

The PULJ takes into consideration the briefs filed by the applicant, the State, and any other parties, recommended license conditions, and public testimony, and issues a decision in the form of a Proposed Order on whether or not the CPCN should be granted and under what conditions. After a prescribed appeal period, a Final Order is released granting or denying the CPCN.

There are certain exceptions where a CPCN is not required, such as for land-based wind power projects no greater than 70 MW; electric generators no greater than 70 MW that consume at least 80 percent of the electricity generated on-site; and generators with capacity no greater than 25 MW that consume at least 10 percent of the electricity generated on-site (see PUC Article 7-207.1).