ENVIRONMENTAL CONSULTING SERVICES

Interstate 25 South Gap Project: Monument to Castle Rock

Pinyon Environmental, Inc. played a key role in supporting the Colorado Department of Transportation’s (CDOT) Planning and Environmental Linkage (PEL) Study for the critical 33-mile stretch of Interstate 25 (I-25) between Monument and C470, El Paso and Douglas Counties, Colorado. This 33-mile portion of I-25 is a vital link between Colorado’s two largest urban areas. High rates of population growth and development statewide, particularly in the Denver and Colorado Springs metropolitan areas, have increased transportation demand throughout the region. The primary goal of the PEL Study was to develop both short-term and long-term alternatives to reduce congestion, improve operational performance, and address future transportation needs along this stretch of I-25.During the course of the PEL, CDOT identified the “Gap” section of the corridor as an urgent priority. A Templated Environmental Assessment (EA) was initiated for the Gap between Monument and Lone Tree, Colorado. This section carries high-speed (75 mile-per-hour) and high-volume traffic through a hilly portion of Douglas County that poses severe winter maintenance challenges, including managing snow removal during severe storms; icing of hills, overpasses and bridges; and poor visibility during storms over the Palmer Divide. The lack of alternate routes and frontage roads through this area frequently leave travelers stranded during lane and highway closures. For both the PEL and the EA, Pinyon led numerous environmental tasks, including biological and cultural resource assessments; wildlife movement studies; air and water quality evaluations; and hazardous materials risk assessments. Their efforts prioritized minimizing impacts to sensitive ecosystems, such as habitats for the federally threatened Preble’s meadow jumping mouse, recommended wildlife crossings to improve movement corridors, and authored programmatic and site-specific Biological Assessments (BAs). Pinyon also managed Section 106 consultation, completing eligibility and effects determinations efficiently for direct and indirect impacts. Throughout the project, Pinyon collaborated closely with CDOT, local municipalities, and federal agencies to ensure compliance with environmental regulations and supported the development of Purpose and Need statements, reflecting their expertise in balancing infrastructure improvements with environmental stewardship. The same consultant team quickly followed up the Templated EA with a series of reevaluations for the Gap that addressed design refinements, enabling construction to move forward quickly and efficiently.

Additional information

Technical Services

Air Quality & Noise, Biological Resources, Cultural Resources, GIS/CAD, NEPA & Planning, Site Characterization & Remedation

Locations

Colorado

Market

Transportation