Environmental Permitting and Compliance for Electric Power

From Prevention of Significant Deterioration (PSD) permitting challenges to specific national and regional regulatory programs focused directly upon the fossil-fueled electric power industry (e.g., Cross-State Air Pollution Rule, Clean Air Mercury Rule), power generation facilities face daunting regulatory hurdles. Trinity has assisted clients with nearly 500 power-related projects, offering an array of services, such as federal air permitting, due diligence environmental investigations, regulatory and environmental compliance management, and environmental regulations training.  Learn more about Trinity's services for the electric power industry including integrated environmental support for new project development.

Client Testimonial

"Trinity Consultants played an instrumental role in conducting our Class I visibility modeling at a new combined cycle combustion turbine generating station. With superior knowledge and expertise, Trinity utilized a refined CALPUFF model that predicted the potential visibility impacts from the station. This effort afforded us the operational flexibility we needed."
Jay Hudson, P.E., Manager
Performance & Environmental Services, Santee Cooper

Environmental Regulatory Round Up

  • Energy & Air Quality Regulation Under the Trump Administration:
    During the Obama administration, EPA issued numerous rules and policies imposing new air quality requirements on the energy sector, including the Clean Power Plan, revised national ambient air quality standards, the Mercury and Air Toxics Rule; pollutant transport rules; and the startup, shutdown, and malfunction SIP Call, to name a few. Under the Trump administration and the new EPA administrator, the policies and roles at the federal level are changing across a wide spectrum of issues, such as agency size and funding, the extent of federal authority over state's rights, enforcement and climate change.  Industry comments and requests made during the comment period for the “Enforcing the Regulatory Reform Agenda” (EO1377) were mostly focused on new source review, national ambient air quality standards, Title V, and hazardous air pollutant issues. For more information on how the changes may impact your site, please contact Scott Osbourn at (407) 982-2891, ext 505 or any of Trinity's power experts in your region.
  • Cross-State Air Pollution Rule (CASPR) Updates
    On September 7, 2016, EPA finalized an update to the Cross-State Air Pollution Rule (CSAPR) for the 2008 ozone national ambient air quality standard (NAAQS).  Under the final ruling, 22 states have revised power sector budgets (tonnage-based state-level emission limits) and allowance trading programs for the NOx ozone season. The EPA is issuing federal implementation plans (FIPs) for the 22 CSAPR update states under which affected electricity generating units (EGUs) in each state are required to reduce emissions to comply with program requirements beginning with the 2017 ozone season (May 1 through September 30). For more information about the CSAPR final rule, click here.
  • EPA Office of Inspector General to Research the Review and Approval Process for AERMOD:
    Over the last several decades of the regulation of air pollutants, industry has generally been one of the most regulated. At the top of the list of industrial sources has, of course, been power plants because of their wide dispersement, their size, their fuels, and the possibility of adding controls. The process has gone from NAAQS compliance under the Clean Air Act, compliance with Prevention of Significant Deterioration incremental air quality, modeling for compliance with the effects on Class I areas under the Best Available Retrofit Technology (BART), MATS, BACT, and other programs to improve air quality. One of the requirements that is followed in this process is performing dispersion modeling to demonstrate that new or modified sources, add-on controls, fuel conversions, and other projects will have an acceptable air quality impact under some or all of the programs listed above. This is accomplished through dispersion modeling following the Guideline on Air Quality Models (40 CFR 51, Appendix W) with the number one preferred model in the last decade and a half being the AERMOD Model. Permit limits, ambient impacts, control and operational strategies have relied upon the results of AERMOD. However, as of June 5, 2017, the Guideline and its preferred AERMOD Model are coming under scrutiny. Click here to learn more.
  • Clean Air Interstate Rule (CAIR)/Clean Air Mercury Rule (CAMR):
    Although there are many, two of the regulatory challenges affecting the electric power industry, particularly for coal-fired boilers, are compliance with the CAIR and CAMR rules. The final CAIR rule was promulgated by EPA on March 10, 2005, and the CAMR was issued as a final rule on March 15, 2005. Both rules are “cap-and-trade” emission reduction programs where an overall cap on emissions is established and then pollutant “allowances” are divided up to those emission source owners required to comply with the program. The EPA's CAIR rule is focused upon reductions of NOx and SO2 emissions from the fossil fuel power industry located in the eastern half of the U.S., while the CAMR rules establish reductions of mercury emissions from coal-fired utility powers located across the entire country. The individual states that are required to implement both these rules must update their State Implementation Plans (SIPs) and gain approval from EPA as to how these programs will specifically be implemented. For more information on either of these rules, please contact any of the Trinity power industry experts.

Project Profiles

  • A major national power generation company proposed to construct a merchant electricity plant with total facility power output of 800 MW. Trinity prepared the Prevention of Significant Deterioriation (PSD) permit application for this facility. The PSD application included a full BACT analysis for CO, NOx, PM, PM10, PM2.5, SO2, VOC, and GHGs; AERMOD dispersion modeling, and a detailed regulatory review. Trinity also conducted ozone impacts analysis and secondary PM2.5 formation analysis as part of the air impacts analysis.
  • A North American energy company was considering construction of several power generation facilities, some of which would be built in nonattainment areas or in the counties that are collectively considered a zone of influence to a nonattainment area. In order to build a power generation facility in these regions, the company would have required emission offsets. Trinity identified potential sources of NOx emission credits and assisted with negotiations for the purchase of these credits.
  • Trinity assisted a power generation facility with a feasibility study for a new coal-fired power plant. Trinity estimated emissions for NOx and SO2, conducted Air Quality Related Values (AQRV) modeling using CALPUFF, and conducted Class I area increment modeling. Trinity demonstrated that the proposed facility would not cause a violation of the Class I Increment, completing the entire analysis in less than one month.
  • Trinity prepared a PSD permit application for a proposed 1,200 MW natural-gas fired power plant to be located in the northwestern U.S. on Native American lands. The project required the submittal of a PSD permit application, a Title V (Part 71) operating permit application, an analysis of the acid rain requirements, and an analysis of the applicability of the New Source Performance Standards (NSPS) and the National Emission Standards for Hazardous Air Pollutants (NESHAPs). The PSD permit application included a Best Available Control Technology (BACT) analysis and a detailed modeling analysis both for the surrounding area (Class II modeling analysis), and the Class I areas. AERMOD-Prime was used in the Class II modeling analysis while CALPUFF was used to determine expected impacts to visibility, acid deposition and PSD Class I Increment levels at all Class I areas within 200 km of the proposed plant.

Case Study

Permitting Large RICE for Power Generation Under the 2017 Guideline on Air Quality Models

Fast-starting, quick-ramping flexible reciprocating internal combustion engines (RICE) units can respond to a sudden drop in wind or solar power as utilities move to renewable energy. For example, a typical boiler may take up to four hours to come online while RICE units can provide power to the grid in about one minute.

Trinity has and is preparing several Prevention of Significant Deterioration (PSD) permit applications for RICE Generating Stations. Each generating station includes multiple RICE units with sizes ranging from 8 MW to 17 MW. The total number of units permitted is a function of the peak power requirement. If 80 MW of generation is needed, either 10 8-MW units or 5 17-MW units could be permitted. The main advantage to installing multiple units is the ability to achieve a heat rate comparable to combined-cycle combustion turbines across the full load range (from one unit to all units). Fuel flexibility is another advantage. RICE units are available that burn either natural gas or liquid fuels or dual-fuel units that can burn both natural gas and liquid fuels.

In the preparation of the permit applications, Trinity had to overcome challenges with:

  • Stack height limits,
  • Demonstrating compliance with the 1-hour NO2 and SO2 National Ambient Air Quality Standard (NAAQS),
  • Demonstrating compliance with the 24-hr PM2.5 PSD Class II Increment and NAAQS,
  • Modeling existing generating units in the cumulative impact modeling, and
  • Assessing the project's impact on ozone and secondary PM2.5

The recent updates to “Appendix W to Part 51 - Guideline on Air Quality Models” (Guideline) were useful in meeting some of these challenges. These updates added clarity by codifying the steps required and the items to be considered when preparing the ambient air quality analysis, but, they also added complexity as they do not specify the methods required to complete the steps. Trinity has the knowledge and expertise to overcome this added complexity.

A few key updates to the Guideline include:

  • Changes to the required emissions input data for nearby sources
  • The inclusion of the Ozone Limiting Method (OLM) and the Plume Volume Molar Ratio Method (PVMRM) as detailed Tier 3 screening techniques for modeling NO2
  • A two-tiered approach for assessing secondary pollutant (Ozone and PM2.5) impacts
  • Removal of CALPUFF as the preferred long-range transport model  

The changes to the required emissions input data for nearby sources simplified the permitting of new RICE units near an existing generating station. The Guideline (Table 8-2) allows the modeler to account for actual operations in developing the emissions inputs for nearby sources. Nearby sources include the unaffected existing generating units. Modeling compliance with the 24 hour PM2.5 NAAQS would not have been possible without this change.

EPA's approval of the OLM and PVMRM into AERMOD as regulatory options removes the alternative model approval requirement for OLM and PVMRM. However, the applicant must demonstrate that OLM and PVMRM are applicable on a case-by-case basis. Trinity developed the justification that OLM and PVMRM are applicable for each project.

The Guideline recommends the following two-tier approach for assessing single-source secondary ozone and PM2.5 impacts: 

  • Tier 1 - The first tier involves using appropriate and technically credible relationships between emissions and ambient impacts developed from existing modeling studies deemed sufficient for evaluating a project's impact. EPA is in the process of developing Modeled Emission Rates for Precursors (MERPs) as a Tier 1 demonstration tool for secondary PM2.5.
  • Tier 2 - The second tier involves a more sophisticated case-by-case application of chemical transport modeling.

The term MERP describes a precursor emission rate that is expected to result in a change in ambient ozone or secondary PM2.5 that is less than a specific air quality concentration threshold. Therefore, if the project's precursor emissions are below the MERPs, the project is not expected to cause or contribute to a violation of the NAAQS due to ozone and secondary PM2.5 formation. Otherwise, if the project's precursor emissions are above the MERPs, the MERPs can be used to estimate the project's ozone and secondary PM2.5 impact. Trinity was able to use the draft MERPs to assess the project impact on ozone and secondary PM2.5.

For one of the projects, the closest Class I Area to the project is > 50 km. With the removal of CALPUFF as a preferred model, modeling Class I Increment requires an alternative approach. Following the Guideline recommendations, AERMOD modeling conducted at a distance of 50 km in all directions showed the project was insignificant.

If you are interested in learning more about this Large RICE power generation permitting or how Trinity can assist your facility with environmental permitting, please contact Ms. Latha Kambham in Trinity's Dallas Office by calling (972) 661-8100 or any of Trinity's listed power experts in your region

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