2025-03-14_PERMIT FILE - M2025016 ‎(37)‎

• Permit No: M2025016
• IBM Index Class Name: Permit File
• Doc Date: 3/14/2025
• Doc Name Note: Exhibit H Cultural Resources
• Doc Name: Application
• From: Raptor Materials LLC
• To: DRMS
• Email Name: JR2
• Email Name: AME
• Email Name: EL1
• Media Type: D
• Archive: No

Technical Memorandum File and Literature Review
P125 Gravel Mine Project, Weld County, Colorado

ERO Project #24-180 2
ERO Resources Corporation
Methodology
The purpose of the cultural resource file and literature review is to determine if any previously
documented cultural resources listed in or eligible for listing in the National Register of Historic Places
(NRHP) or State Register of Historic Places (SRHP) could be impacted by the proposed project. A
“cultural resource” is defined as an archaeological site, structure, or building constructed 50 or more
years ago (Little et al. 2000). A cultural resource listed in or eligible for listing in the NRHP/SRHP is a
“historic property.” To assist with project planning and potential consultation obligations under Section
106 of the NHPA (36 Code of Federal Regulations 800) and the State Register Act (Colorado Revised
Statutes 34-80.1-104), ERO reviewed the previous cultural resource surveys and resource
documentation completed in the project area by conducting a file search with the Office of Archaeology
and Historic Preservation (OAHP). The OAHP provided the results to ERO on August 1, 2024 (File Search
No. 00-3637).
Results
The file search identified no previous cultural resource surveys that intersect the project area. However,
the file search identified three previous cultural resource surveys located just north of the project area
(Table 1). All surveys were completed from 2005 to 2012.
Table 1. Previous cultural inventories near the project area.
State Project No. Report Title (Date) Institution
MC.CH.R175 An Intensive Archaeological Resource Inventory of Proposed Safety
Improvements on US Highway 287 and State Highway 66, Larimer and Weld
Counties, Colorado (Sta-R400-173) (2005)
Colorado Department of
Transportation (CDOT)
WL.CH.NR44 An Intensive Archaeological Resource Inventory of the Proposed St. Vrain
River Realignment on State Highway 66 West of Gowanda, Weld County,
Colorado (CDOT # STA 0661-009) (2006)
CDOT
WL.CH.NR55 An Intensive Cultural Resources Inventory for the Replacement of the St.
Vrain River Bridge on State Highway 66, Weld County (CDOT Project FBR
006a-002/STA 066a-001, SH 66 at St. Vrain Bridge) (2012)
CDOT

The OAHP records indicate no previously documented cultural resources are in the project area (Table
2). Resources recorded north of the project area consist of two historical resources. The resources
include a segment of the Last Chance Ditch (5WL1975.3) and St. Vrain River Bridge D-17-AK (5WL3007).
Table 2. Previously recorded cultural resources near the project area.
Smithsonian
Site No.
Associated
Report Nos. Resource Name/Type NRHP Eligibility Status (Date)
5WL1975.3 Not listed Last Chance Ditch Segment Officially Eligible (2006)
5WL3007 MC.CH.R100 St. Vrain River Bridge D-17-AK Officially Not Eligible (2002)

In addition to the OAHP file search, ERO reviewed existing literature, historical maps, public records,
General Land Office (GLO) records, and aerial images to assess the potential for unknown historical
resources, such as roads, ditches, and buildings, in the project area. ERO reviewed maps dating from
1863 to 1950 (General Land Office 1863; U. S. Surveyor General’s Office 1902, 1950, 1957; U.S. Surveyor