Montrose Environmental Group, Inc. is pleased to announce it has acquired Horizon Engineering, LLC and its affiliate AmTest Air Quality, LLC. Terms of the transaction were not disclosed.
Formed in 1977, Horizon Engineering, LLC is a leading source testing company with offices in Portland, Oregon and Auburn, WA (AmTest Air Quality). Mr. David Bagwell, QSTI and Managing Member of Horizon Engineering, LLC, will continue with Montrose Environmental Group, Inc. as Vice President, Northwest Region in its Air Quality Services Division.
David Bagwell stated, “We are very pleased and excited to join the Montrose team of service providers. We look forward to continuing our commitment of delivering superior customer service and the highest quality point source data. These promises will only be strengthened by the Montrose depth, talent base, and resource pool while providing our personnel with new and challenging opportunities.”
Jeremiah Yu, Co-Chief Executive Officer of Montrose Environmental Group, added, “We are extremely excited to have Horizon and AmTest join Montrose. With Horizon’s reputation as a leading provider of source testing, Montrose is now better positioned to serve our clients throughout the Northwest and the rest of the country.”

About Horizon Engineering, LLC

Horizon Engineering was founded in 1977 with the purpose of serving the environmental and energy needs of industrial clients. Horizon’s present work is centered on air pollution emission testing. Horizon acquired AmTest Air Quality in 2010. AmTest complements Horizon with an experience base of providing excellent stack testing service that goes back to 1982.
Horizon serves a variety of clients throughout the Western US, Alaska, Hawaii, Asia, and Europe.
Horizon Engineering is C.A.R.B. certified to perform emissions testing in California. Horizon manages its business in conformance with ASTM D7036-04 “Standard Practice for Competence of Air Emission Testing Bodies.” Horizon holds interim accreditation status from the Stack Testing Accreditation Council (STAC), which is a third party accrediting body. For more information, visit

About Montrose Environmental Group, Inc.

Montrose Environmental Group, Inc. is a national, high-growth environmental company offering Air Quality and Environmental Laboratory services to a diverse range of clients in industry and government. Headquartered in Orange County, California, Montrose Environmental Group, Inc. has 25 offices and approximately 425 employees nationwide. For more information, visit