Alliance Technical Group Acquires Horizon Air Measurement Services

Alliance Technical Group (ACP-backed) Acquires Air Quality Services (AQS)

April 1, 2021

Environmental Services

Alliance Technical Group, the environmental testing and compliance platform backed by Align Capital Partners, has acquired Air Quality Services (AQS), a 1998-founded provider of stack testing, ambient air monitoring, and CEMS services based in Evansville, Indiana. The add-on expands Alliance’s service capabilities into continuous emissions monitoring and strengthens its Midwest footprint.

Morgan Stanley Capital Partners Acquires Alliance Technical Group from Align Capital Partners

July 20, 2021

Environmental Services

Morgan Stanley Capital Partners (MSCP) has acquired a controlling interest in Alliance Technical Group, a Decatur, Alabama–based provider of air emissions testing, monitoring and analytical services, from Align Capital Partners. MSCP will partner with Alliance's management led by CEO Chris LeMay to continue geographic expansion and M&A-driven growth while the management team and employees retain a meaningful ownership stake.

Alliance Technical Group Acquires Environmental 360

June 20, 2025

Environmental Services

Alliance Technical Group acquired Environmental 360, LLC to expand its environmental consulting, monitoring, and compliance capabilities. The deal strengthens Alliance's onsite field services and emissions/compliance monitoring offerings for industrial clients across the United States.

Alliance Technical Group Acquires Emission Monitoring Service, Inc. (EMSI)

April 1, 2021

Environmental Services

Alliance Technical Group, a portfolio company of Align Capital Partners, acquired Emission Monitoring Service, Inc. (EMSI) in a transaction that closed April 1, 2021. EMSI, headquartered in Baytown, Texas, provides emissions leak detection, repair and regulatory compliance services and employs more than 300 technicians; the deal provided liquidity to an absentee majority owner and expands Alliance's environmental services footprint and capabilities.

Alliance Technical Group Acquires Slipstream Environmental Services

May 13, 2025

Environmental Services

Alliance Technical Group has acquired Slipstream Environmental Services, a Sheridan, Wyoming-based specialist in combustion source emissions testing for the oil & gas sector. Slipstream's ~45 employees and fleet of 23 mobile testing labs will integrate into Alliance's national network to expand combustion source testing capabilities and regulatory compliance services.

Alliance Holdings Acquires Blue Mountain Environmental

November 10, 2020

Environmental Services

Alliance Holdings, the environmental services platform backed by Align Capital Partners, has acquired Blue Mountain Environmental Management Corporation. The deal expands Alliance’s air emissions (stack) testing and LDAR capabilities in the Northeastern and Midwestern United States as part of its ongoing add-on buildout to create a national emissions testing platform.