DAQ-2025-001863

195 North 1950 West • Salt Lake City, UT
Mailing Address: P.O. Box 144820 • Salt Lake City, UT 84114-4820
Telephone [phone] • Fax [phone] • T.D.D. 800 346-3128
www.deq.utah.gov
Printed on 100% recycled paper
State of Utah

Department of
Environmental Quality

Tim Davis
Interim Executive Director

DIVISION OF AIR QUALITY
Bryce C. Bird
Director

SPENCER J. COX
Governor

DEIDRE HENDERSON
Lieutenant Governor
DAQC-342-25
Site ID 10259 (B4)

Derek Forsberg
Northwest Pipeline LLC
295 Chipeta Way
Salt Lake City, UT 84108

Dear Mr. Forsberg:

Re: Northwest Pipeline LLC – Cisco CS, Solar Centaur Compressor Turbines P001-2 Stack
Emissions Testing – Protocol Review and Test Date Confirmation – Grand County

The emission testing protocol received April 2, 2025, has been reviewed and determined to be
acceptable. Stack testing of Turbines P001-2 is approved for May 6-7, 2025.

Acceptance of a protocol does not relieve the owner/operator and the testing contractor from strict
adherence to all applicable EPA methods, Utah Division of Air Quality (DAQ) policies, Utah Air
Quality Rules (UAQR), and methods approved by the director. Any deviation from EPA methods,
DAQ policies, UAQR, and methods approved by the director must be addressed separately and
express written consent given prior to commencement of testing.

The DAQ requires that all test reports include a statement signed by a responsible official
certifying that:

A. Testing was conducted while the source was operating at the rate and/or conditions
specified in the applicable approval order, operating permit, or federal regulation.

B. During testing, the source combusted fuels, used raw materials, and maintained
process conditions representative of normal operations, and operated under such
other relevant conditions specified by the director.

C. Based on information and belief formed after reasonable inquiry, the statements
and information contained in the report are true, accurate, and complete.

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DAQC-342-25
Page 2

If you have any questions, call me at [phone] or e-mail me at [e-mail].

Sincerely,

Robert Sirrine, Environmental Scientist
Division of Air Quality

RS:rh

cc: Southeast Utah Health Department
Emissions Science, Inc.

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