What is a Preliminary Environmental Study (PES)?

The National Environmental Protection Act (NEPA) is a law that acts as a process of due diligence before a project can take place. The NEPA review process can be lengthy as it has review and disclosure standards that must occur to greenlight a project. Agencies must complete a preliminary environmental study (PES) to ensure NEPA compliance. A PES is the first step in NEPA compliance and aims to set a standard for the decision-making process to integrate environmental factors into project plans. All Local Public Agency (LPA) federal aid projects must complete a PES form, considering various requirements and extensive expectations that assess the risk level of potential impacts.  

A PES aims to maintain and enforce compliance with NEPA and the California Environmental Quality Act (CEQA) initiatives to regulate projects off the State Highway System (SHS). The California Department of Transportation (Caltrans) is responsible for delegating and overseeing any SHS plan, design, maintenance, and more.

Completing a PES Form 

A PES form focuses on the project plan and description and requires a detailed map of the proposed project. A review process follows, giving resource and regulatory agencies an opportunity to review technical information. The final procedure includes verifying research findings in the field. 

General considerations outlined in a PES form include:

  • Cultural and Biological Resources Management
  • Land Use, Community, and Farmland Impacts
  • Relocation Impacts
  • Floodplains, Waterways, Water Quality/Resources, and Coastal Zones Impacts
  • Hazardous Waste Zones and Materials
  • Noise and Visual Quality Control


Learn more about initiating a Preliminary Environmental Study (PES) for NEPA here.

How we can help

In an ever-changing regulatory and sustainability environment, FCS understands the challenges you face. Our highly qualified environmental specialists, energy management consultants, and technical experts deliver integrated, industry-specific solutions that move your project forward—so that you can focus on what matters.