Oregon Department of Transportation

Region 5 Geology 3012 Island Avenue

La Grande, OR 97850

July 18, 2025

To: Paul Howland Assistant D12 Manager, Pendleton

Rich Lani District 12 Manager, Pendleton

From: Scott Billings Region 4/5 Engineering Geologist

Subject: Material Source Narrative D12 Chip Seal Rock Production 2025 Project Grant, Wheeler, and Morrow Counties

RE: Prospective Material Source Hoogie Doogie Quarry ODOT Source #OR-35-008-5, DOGAMI #35-0003 Sec. 12, T. 09 S., R. 23 E., W.M.

OR19 (Hwy 005), M.P. 83.70

This narrative memo and the attachment (laboratory testing results) should be duplicated and distributed to all bidders that inquire about this prospective material source, according to Section 00120.25 of the 2024 Standard Specifications for Highway Construction. This is an existing BLM-owned ODOT-controlled material source.

ODOT Region 5 is offering this prospective material source for production of crushed aggregate for chip seal aggregate. Not knowing where the Contractor will produce rock from, the development plan for this source is based upon estimated project material requirements of 6,375 cubic yards (cyds) of material. The quarry development plan sheets identify an excavation area and associated volume adequate to supply the aggregate materials necessary to complete this project.

Hoogie Doogie Mountain Quarry is located in the Blue Mountain physiographic province of northeastern Oregon. This area that includes the quarry is shown on published geologic maps (P.T.

Robinson, 1975; Walker & MacLeod, 1991) as Picture Gorge Basalt, part of the Columbia River Basalt Group erupted predominantly from 15 to 16.4 Ma. during the middle and lower Miocene geologic epoch. A thick succession of basaltic flows and volcanic ejecta form the bedrock exposed on the slopes of Hoogie Doogie Mountain. Based on observed rock exposures a thick sequence of basalt forms the steep bluffs from at least the existing highway elevation up for approximately 100 feet, with welded vitric-crystal tuff forming the more gently sloping surface above. The basaltic rocks are hard and have close- to wide-spaced joint fractures. The welded tuff is moderately hard and massive with few

July 18, 2025 Page | 2 fractures, and is relatively impermeable to water. The welded tuff surface has been scoured by water runoff, leaving drainage swales and only isolated patches of thin soil overburden.

According to Agency records, ODOT Maintenance and ODOT contractors for State Transportation Improvement Projects (STIP) have utilized this site several times in the past for highway aggregates since it was appropriated from the BLM in 1958, and revised in 1973. The last ODOT operation at the site was in 2012 for producing 10,000 cyds of highway sanding rock for the OR 19/207: D12 Sanding Rock Production. Production blasting from the 2012 entry resulted in fractured rock covering and closing a portion of the highway for several days. Oversize rock was also produced from the production blasting in 2012. Our files on this material source are limited and there are no documented problems associated with the material for use as highway aggregates. A laboratory testing result is attached to this Narrative.

No subsurface exploration drilling has been performed at this material source to date. However, there are numerous exposures of bedrock in cliffs and road cuts that readily show the geologic characteristics of the rock to be excavated, and the near horizontal weak planes (“bake zones”) within them that separate individual flows. Contractors should be aware of these conditions and take appropriate measures in excavating to accommodate them.

The development concept for this source is for long term intermittent use. The developmental concept for the current operation is to excavate an elevated bench in the rock cliff face. The benches can eventually be lowered to the highway floor elevation with successive benches up the rock face in future entries.

Excavations can then progress east and west. Contractor operations shall avoid and protect existing property boundary and survey markers, as well as any buried utility cables and overhead utility lines and poles. Even with a successful blast, special equipment or equipment setup may be necessary for secondary reduction, or to enable the contractor to handle larger (“over size”) material if it is generated.

In conformance with the Standard Specifications for Highway Construction, subsection 00120.15 Examination of Work Site and Bidding Documents, Contractors should make an on-site visit to this source to familiarize themselves with the existing conditions and appearance of the source and to visually inspect the existing quarry faces and the surrounding ground surface in advance of bid preparation. Based on the on-site visit and review of all available information, Contractors will then be able to use their best judgment to prepare a bid based upon existing site conditions, the conditions they expect to encounter at the time of the proposed operation, and on the most accurate information available for the source.

Documentation contained within this material source narrative packet, such as the development plan maps and operating specifications, is for informational purposes only; they are not meant to replace those pages supplied in the Project Bid Packet.

Attachments:

Laboratory Testing Results