Environmental Support for Deepwater Ports (DWPs), LNG Terminals, and Offshore E&P

For more than 25 years Trinity Consultants has provided dispersion modeling, permitting, and compliance support for a wide range of coastal operations including oil, gas, and sulfur exploration, production, and processing in the Outer Continental Shelf (OCS), Deepwater Ports (DWPs), and liquefied natural gas (LNG) terminals. The regulatory landscape that applies to offshore and coastal operations is extremely complex. Trinity has played a key role in the success of many of these capital intensive projects by identifying and demonstrating compliance with the applicable health, safety, security, and environmental (HSSE) obligations while helping our clients obtain construction authorization under multiple licensing regulations from the various regulatory agencies that have jurisdiction over offshore facilities. 

Deepwater Ports 

The Deepwater Port Act (DWPA) regulates fixed and floating manmade structures located beyond State seaward boundaries that are used as a port or terminal for the transportation, storage, or further handling of oil or natural gas for transportation to or from any State. Trinity has prepared Deepwater Port License (DWPL) application materials for both LNG and crude oil and condensate DWPs and has met and worked with representatives of the U.S. Coast Guard (USCG) and Maritime Administration (MARAD) who coordinate processing of DWPL applications and cooperating agencies which include the Environmental Protection Agency (EPA), Bureau of Ocean Energy Management (BOEM), and appropriate state environmental agencies. Per subchapter NN of the Code of Federal Regulations (33 CFR 148-150), DWPL applications must address the requirements of the National Environmental Policy Act (NEPA), the Clean Air Act (CAA), and the Clean Water Act (CWA). As an example, Trinity's support for the first DWPL application for crude condensate export included the preparation and submission of the following documents:

  • Air quality information for the NEPA Environmental Impact Statement (EIS)
  • New Source Review (NSR) permit application including Prevention of Significant Deterioration (PSD) and Minor NSR
  • Air quality dispersion modeling analysis (NAAQS and toxics analysis)
  • Case-by-case MACT application for the Single Point Mooring (SPM) system for crude export through Very Large Crude Carriers (VLCC)
  • Title V federal operating permit
  • Construction authorizations for onshore facilities - tank farm, booster station, and valve station

LNG Terminals

The U.S. historically imported LNG from other countries. With the development of innovative technologies and plentiful reserves, the U.S. has become the world's leading natural gas producer.1 This has resulted in a shift in focus to LNG export from the U.S. As a result, the number of license applications for LNG terminals has expanded significantly in the last decade.

The Federal Energy Regulatory Commission (FERC) is an independent agency that regulates the interstate transmission of electricity, natural gas, and oil. The FERC also reviews proposals to build LNG terminals and interstate natural gas pipelines including compressor stations. In addition to the FERC requirements for LNG terminals, interstate natural gas pipelines including compressor stations are also required to obtain approvals and permits from the state agencies in which the operations are located. For example, an LNG terminal in Louisiana is required to obtain an air permit from the Louisiana Department of Environmental Quality (LDEQ) in addition to the FERC approval.  

Trinity has extensive experience in assisting LNG terminals with preparation of air permit applications and critical portions of the NEPA EIS. Specifically, Trinity has provided the following services to LNG terminals:

  • NSR permit application including PSD and minor NSR
  • Air quality dispersion modeling analysis (NAAQS and HAP/TAP analysis)
  • Case-by-case MACT applicability
  • Title V operating permit
  • Preparation of Resource Report 9 (RR9)
  • Client advocacy 

Oil and Gas and Sulfur Operations in the Outer Continental Shelf

To regulate exploration, development, and production of oil, gas, sulfur, and other minerals in the Outer Continental Shelf (OCS) of the U.S., the U.S. Secretary of the Interior (Secretary) authorized the Bureau of Ocean Energy Management (BOEM) as the regulatory agency. BOEM requires the submittal and approval of certain plan documents before drilling activities can be initiated. For drilling activities these plans typically consist of one of the following:

  • EP, or Exploration Plan- required to conduct exploratory drilling on any offshore lease
  • DOCD, or Development Operations Coordination Document- required for development and production drilling activities on any offshore lease

Regulations governing the requirements for EP and DOCD plans are codified under Title 30 of the Code of Federal Regulations at 30 CFR Part 550. An EP or DOCD plan must include air emissions information for the proposed activities. In general, this information includes projected emissions, frequency and duration of emissions, bases for calculations, equipment information, emissions reductions measures (if applicable), and dispersion modeling (if applicable). Before submitting an EP or DOCD plan to BOEM for approval, the applicant must demonstrate that onshore air quality impacts from proposed offshore activities, as compared to the National Ambient Air Quality Standards (NAAQS), will not adversely affect human health or the environment. Emissions from offshore sources must be quantified using EPA-approved methodologies. These sources include fuel burning sources, such as drilling rigs, generators, flares, and supply vessels as well as sources of fugitive emissions. Trinity has supported the submittal of the air quality component of these plans for several platforms and drillships in the eastern and western Gulf of Mexico (GOM).

In some OCS areas, a combination of approvals is needed from EPA, BOEM, and local authorities. In other OCS areas, BOEM is the sole regulatory authority for obtaining the necessary approval for air emissions. As an example, in the western GOM (west of the 87.5 degree longitudinal line), EPA does not issue air permits for construction or operation of offshore activities. Instead the approval is solely obtained through the aforementioned EP or DOCD plan.

Trinity has provided the following services to OCS facilities:

  • BOEM GOADS reporting
  • Air Quality Report (AQR) preparation
  • GHG reporting (Corporate and 40 CFR 98)
  • Fugitive emission campaigns
  • ODS & PCB inventories
  • Client advocacy
  • Air dispersion modeling

Outer Continental Shelf (OCS) Facilities

OCS facilities are defined by the Outer Continental Shelf Lands Act as sources located offshore of the States along the Pacific, Arctic, and Atlantic Coasts, and along the Gulf Coast off the State of Florida east of 87.5° longitude. OCS facilities do not include Deepwater Ports for crude oil or LNG import/export. The Clean Air Act (CAA), at Section 328, directs the U.S. EPA to regulate air emissions associated with these OCS facilities. The EPA has promulgated regulations at 40 CFR 55 that define the applicable permitting, compliance, and enforcement requirements for OCS facilities.

Under these regulations, the EPA remains the permitting authority for most facilities - both permanent and temporary.2  As a result, pre-construction authorization in accordance with the Federal PSD permitting program, and subsequently, a Title V air operating permit per 40 CFR 71 are required. This is analogous to onshore facilities attaining and maintaining compliance with the NAAQS. These facilities can also be subject to applicable air emissions standards under 40 CFR 60 (New Source Performance Standards) and standards under 40 CFR 63 (National Emissions Standards for Hazardous Air Pollutants). If the OCS facility is located within 25 nautical miles of a state seaward boundary, the facility must also comply with applicable air quality requirements of the nearest/corresponding onshore areas (e.g., state permitting and modeling, emissions standards, and compliance requirements).

In addition to the CAA requirements that are similar to onshore facilities, there are notable, unique considerations for OCS facilities, including:

  • “Potential emissions” by definition at 40 CFR 55.2 includes emissions from vessels servicing or associated with an OCS source when they are within 25 miles of the facility. This explicit inclusion of a mobile source within the total direct emissions required to be authorized under stationary source programs is unique to OCS facilities, and can introduce challenges for permitting and air dispersion modeling demonstrations. 
  • EPA also has the ability to issue temporary permits (up to 2 year-duration of operations) for temporary OCS facilities. In order to qualify for these temporary permits, the air quality impacts (demonstrated through dispersion modeling) must not affect areas with PSD increment exceedances and must remain below significant thresholds at Federal Class I areas.
  • EPA reviews and issues the air permit only for a project. Additional authorization is likely required for non-air environmental impacts from BOEM, and if the project involves drilling, additional authorization will be required by DOI.

Trinity has extensive project experience with, and understanding of, the unique OCS regulatory requirements. With the experience to anticipate air permitting impacts to scope and schedule, and the modeling expertise and relationships with EPA and local agency reviewers, Trinity identifies key air permit authorization risk mitigation strategies. Trinity's ability to define strategic options for air permitting for OCS facilities has proven extremely valuable while working with multi-disciplinary project teams to balance the project design and multi-agency authorization requirements.

Offshore Dispersion Modeling

Offshore dispersion modeling is typically required to demonstrate acceptable onshore air quality impacts from proposed offshore activities. Trinity has performed offshore dispersion modeling analyses for emissions from deepwater ports, drillships, platforms, and tankers/vessels in the U.S. as well as other parts of the world. Models typically incorporate emissions from the source types listed above, source exhaust stack parameters, and the coordinates of these offshore emissions sources. Impacts are typically predicted at the shoreline or nearby federal Class I areas, depending in guidance from the regulatory agency. In some cases, impacts are also determined at offshore locations (e.g., fishing zones, coastal safety zones, state seaward boundaries).

There are several dispersion models available for modeling offshore sources, including OCD (Offshore & Coastal Dispersion), CALPUFF, AERMOD (with AERCOARE). Each of these models has unique features that can be utilized depending on the type of analysis needed. 

  • OCD - OCD is currently on EPA's list of preferred models. OCD was developed by EPA in conjunction with BOEM's predecessor agency, the MMS, in the late 1980s. It is an hourly, steady-state model used to predict the onshore concentration of air pollutants emitted from offshore sources. This model is suitable for faster, albeit more conservative results.
  • CALPUFF - Although currently not on EPA's list of preferred models, EPA considers this model to be suitable as a screening technique for long range transport (distance > 50 km). CALPUFF is a more sophisticated model than OCD, and can be used for over-land AND over-water modeling. Modeling using CALPUFF typically requires a significant amount of pre-processing and post-processing of data. This model is also capable of handling regional haze and acid deposition, unlike OCD or AERMOD (with AERCOARE).
  • AERMOD (with AERCOARE processor, beta version) - The standard AERMOD model is not considered suitable for over-water dispersion modeling analysis. This is because the standard version of the model is able to handle over-water meteorological conditions that differ drastically from over-land meteorological conditions. The AERCOARE meteorological data processor allows for the use of AERMOD over water. However, unlike CALPUFF, the accuracy of modeling using AERMOD (with AERCOARE) is limited to 50 km. This model is also considered to be a beta version since a final EPA approved version has not yet been released.

Each of these offshore dispersion models is uniquely capable of handling over-water meteorological data challenges. Together, these models can incorporate water temperature, buoyancy, over-water air temperature, coastal fumigation, and mixing effects.   

[1] Mark Mills, “SHALE 2.0 Technology and the Coming Big-Data Revolution in America's Shale Oil Fields,” Manhattan Institute, Energy Policy and the Environment Report No. 15, May 2015

[2] The permitting authority is typically the assigned EPA Region, though, in some instances the EPA may delegate authority to an adjacent or corresponding state or local agency.