HomeMy WebLinkAboutEngineer's Observation Letter 11.25.25(970) 274-2343 • Jeff@IronMountainEng.com • P.O. Box 2316, Glenwood Springs, CO 81602
November 25, 2025
Garfield County Community Development Department
108 8th Street, Suite 401
Glenwood Springs, CO 81601
RE: Primo Return Terminal Retaining Wall – Construction Review (Permit # BLCO-07-25-9380)
Mr. Plano:
Iron Mountain Engineering (IME) was retained by Ski Sunlight to provide the initial wall layout and
conceptual design guidance for the retaining wall constructed at the return terminal of the new Primo
Lift. The premanufactured gravity-block retaining wall system used in the project—including
engineering of the proprietary wall components, internal stability calculations, and detailed design—was
prepared by others.
As part of the County’s permit approval, a condition was included requiring third-party engineering
inspection during construction to verify the wall was installed in accordance with the approved design.
IME worked with Sunlight Ski Resort throughout their summer projects but was not informed of Garfield
County’s wall inspection condition until after the wall was completed. As such, I did not observe or
document the installation process, buried components, subsurface conditions, compaction, drainage
elements, or foundation preparation. During construction I had several conversations with Ross Terry
about the wall, drainage and material procurement. These conversations lead me to believe that care
was being taken to follow the design requirements.
At the request of Garfield County and Ski Sunlight, Iron Mountain Engineering conducted a post-
construction visual inspection of the completed retaining wall. This inspection was limited to elements
visible at the time of observation. During my inspection, I observed that the grade on the interior face
of the wall has exposed gravel for drainage per the design drawings. This gravel is not capped with the
“4 oz Non-Woven Filter Fabric” or “8” of Lower Permeable Soil” per the design drawings. This final
grading step prevents soils from filtering into the gravel drainage system over time and clogging the
drainage outlets. I have consulted with the engineer of record (Ben Daiss) regarding this final step. He
agreed that completing this final layer is necessary but can be completed next summer. Sunlight is
aware of the requirement and will complete the final step next summer when access to the area is no
longer congested with contractors completing the ski lift. Outside of the final grading cap noted, the
retaining wall appears to generally conform to the layout, geometry, and exposed features shown in the
design documents prepared by Soil Structures Engineering, LLC. No signs of distress, displacement, or
instability were observed during the site visit.
Because Iron Mountain Engineering did not observe construction and cannot assess concealed or buried
elements of the wall system, this letter does not certify or attest to:
(970) 274-2343 • Jeff@IronMountainEng.com • P.O. Box 2316, Glenwood Springs, CO 81602
• the adequacy of foundation preparation;
• subsurface conditions;
• internal drainage;
• compaction of retained soils;
• installation of buried wall units or reinforcement; or
• any portion of the work not visible during the post-construction inspection.
This letter is provided solely to document that the finished, exposed portions of the retaining wall
appear consistent with the intended design configuration (except as noted) and with industry
expectations for a gravity-block system of this type.
Please contact me if additional information is needed or if the County requires a additional information
or documentation.
Sincerely,
11/25/25
Jeff Peterson P.E.
Iron Mountain Engineering