Greenfield sites are often treated as the faster path to development. Fewer legacy constraints, fewer visible risks, fewer barriers to entry. Yet, greenfield sites still present environmental and regulatory considerations that must be carefully assessed and managed from the outset.
For developers working to bring solar, wind and battery energy storage projects online in the U.S., early site due diligence plays a critical role in keeping projects on track. Missteps at this stage can delay timelines by months and add significant unexpected costs.
Early site due diligence is more than a preliminary step. It defines how a project moves through design, permitting and financing, and more importantly, how a project is developed responsibly.
Greenfield sites still carry environmental risk
Early site due diligence for greenfield projects focuses on constraints that may not seem immediately present but affect every decision thereafter. These include wetlands and waterways, threatened and endangered species, cultural resources, environmental review requirements and permitting pathways.
Individually, each factor may appear manageable. Combined, they determine whether a site can support a viable layout, meet regulatory thresholds and move through approvals without redesign.
Identifying these constraints early means you can adjust the siting, sequencing and permitting strategy before costs are locked in. Taking a strategic approach early in the process helps developers minimize environmental impacts, comply with regulatory requirements, manage costs more effectively, and engage with communities in a more meaningful and informed way.
Three areas of environmental due diligence that shape outcomes
Effective early site due diligence typically contains three essential elements: environmental site assessments, wetland and waterway impacts, and natural and cultural resources, including endangered species. Together, these core studies provide a more complete understanding of site considerations and the appropriate regulatory pathways for permitting.
Environmental site assessments
Even on greenfield sites, unknown historical or adjacent land uses can introduce liabilities that affect financing, permitting and site viability. Phase I Environmental Site Assessments (ESAs) are a foundational component of due diligence, used to understand potential environmental risk.
These assessments include on-site reconnaissance, review of historical records and interviews with property owners. They help uncover risks such as hazardous material storage, nearby industrial use, pipelines or undocumented dumping, and may lead to Phase II investigations or even Phase III remediation.
Identifying these conditions early allows developers to:
- Avoid sites with significant remediation requirements
- Incorporate mitigation strategies into project planning to avoid natural and cultural resources
- Reduce the likelihood of unexpected delays during permitting or financing
Jurisdictional waters and wetlands
Wetlands and other jurisdictional waters are among the most common sources of permitting complexity with renewable energy projects. The U.S. Environmental Protection Agency’s (EPA) Clean Water Act regulates activities that impact these water resources and plays a central role in project approvals.
The craft of waterway and wetland delineation involves identifying and mapping the boundaries of aquatic resources in a particular area, an essential step for site planning and regulatory compliance.
While desktop data can indicate potential wetland presence, it can lack the resolution needed to define boundaries accurately. We use a multi-parameter approach that analyzes hydrology, soils and vegetation and field-based mapping to determine where regulated areas begin and end.
This information is critical to:
- Establish project layout and infrastructure placement
- Determine permitting requirements across jurisdictions
- Avoid redesigns caused by inaccurate early assumptions
Early delineation enables developers to design around constraints and incorporate mitigation measures while supporting the long-term protection of these critical ecosystems.
A recent example of this approach comes from the Bayou Chicot Solar project in Louisiana, where early wetland delineation played a key role in site planning. The project team evaluated 433 acres of the site’s 1,817 total acres for potential wetland impacts. Through early environmental assessment and careful design, the team limited disturbance to less than half an acre, well below regulatory thresholds. This type of early insight allows developers to identify constraints upfront and adjust layouts accordingly, reducing the likelihood of redesign and helping projects move more efficiently through permitting.
Regulatory pathway alignment through limited NEPA review
Understanding the regulatory landscape early in the process helps avoid delays and streamline permitting. A limited National Environmental Policy Act (NEPA) review gives you a faster, more focused way to evaluate environmental impacts and identify applicable requirements.
Compared to a full Environmental Impact Statement (EIS), limited NEPA reviews are typically used for projects with more contained impacts and require a narrower scope of documentation.
These assessments often include desktop review of threatened and endangered species and cultural resources, followed by onsite confirmations. They often also include a permitting matrix outlining applicable federal, state and local requirements related to water resources (surface water, wetlands and wetland soils), protected species (rare, threatened or endangered), and cultural resources (historical and archaeological areas of concern).
By clarifying the regulatory landscape early, developers can:
- Anticipate permitting timelines
- Identify potential approval challenges
- Align project planning with compliance expectations
Desktop vs. field assessments: balancing speed and accuracy
Desktop assessments are often the starting point for early site due diligence, allowing developers to quickly evaluate multiple locations using available data sources. This approach lets you screen multiple sites quickly and narrow down options early.
However, desktop analysis has limitations. It relies on existing datasets, which may be outdated, incomplete or not detailed enough to reflect site-specific conditions. Important factors such as wetland boundaries, soil composition or vegetation may not be fully captured, creating gaps between initial assumptions and actual site conditions.
Field-based assessments help close this gap by providing direct, site-specific insight. Through on-site reconnaissance, wetland delineation and targeted environmental surveys, project teams can validate desktop findings and identify constraints that may not be visible in existing data.
Rather than replacing one approach with the other, the most effective due diligence strategies combine both. Desktop tools provide speed and broad coverage, while field assessments add accuracy and confirmation. Integrating these approaches early in the process allows developers to make more informed decisions, reduce uncertainty and avoid adjustments later in project development.
A more strategic approach to early site due diligence
As renewable energy projects grow in scale and complexity, early site due diligence is becoming more closely tied to overall project performance. The ability to identify constraints, align with regulatory requirements and validate site conditions early can have a direct impact on timelines, costs and long-term viability.
Developers who take a more integrated approach, combining desktop analysis with targeted field assessments and multidisciplinary expertise, are better positioned to reduce uncertainty and move projects forward with confidence. Rather than serving as a standalone step, early due diligence becomes an input into smarter planning and more efficient execution.
By connecting the right environmental, biological and regulatory expertise with quality desktop analyses, field-based evaluations and GIS-enabled mapping, renewable energy developers can:
- Identify and manage environmental and regulatory risks early
- Clarify permitting pathways and requirements
- Optimize site selection and project design
This coordinated approach reduces duplication of effort, minimizes delays and helps you move projects forward with confidence.