Golden Gate Capital Launches Stonehill Environmental Partners and Acquires Waterfield Midstream Assets

NGL Energy Partners LP Acquires Hillstone Environmental Partners from Golden Gate Capital

November 1, 2019

Oil & Gas

NGL Energy Partners LP has agreed to acquire all equity interests of Hillstone Environmental Partners LLC from Golden Gate Capital for approximately $600 million. The acquisition adds Hillstone's produced water pipelines and disposal well network in the Northern Delaware Basin to NGL's existing Delaware Basin water platform, increasing disposal and transportation capacity and providing long-term contracted volumes.

Energy Transfer Acquires WTG Midstream for $3.25 Billion

May 28, 2024

Oil & Gas

Energy Transfer LP agreed to acquire WTG Midstream Holdings LLC in a transaction valued at approximately $3.25 billion, comprising $2.45 billion in cash and ~50.8 million newly issued Energy Transfer common units. The deal, from affiliates of Stonepeak, the Davis Estate and Diamondback Energy, adds WTG's Permian-focused midstream assets — including a 6,000-mile pipeline network, eight processing plants (≈1.3 Bcf/d) and a 20% interest in the BANGL NGL pipeline — to Energy Transfer's footprint to enhance its gas/NGL supply, processing and downstream capabilities.

SK Capital Partners Acquires Milestone Environmental Services

October 4, 2023

Environmental Services

SK Capital Partners has acquired a controlling stake in Milestone Environmental Services from Amberjack Capital Partners, with Milestone CEO Gabriel Rio remaining in place and retaining significant ownership. The deal positions SK Capital to grow Milestone’s waste management platform and accelerate its Milestone Carbon subsidiary’s development of permanent carbon sequestration projects in the U.S., particularly in energy and industrial markets.

GAI Consultants Acquires PGH Petroleum & Environmental Engineers

April 6, 2022

Engineering Services

GAI Consultants, an employee‑owned engineering, planning and environmental consulting firm headquartered in Homestead, Pennsylvania, acquired PGH Petroleum & Environmental Engineers of Austin, Texas. The transaction, advised by Generational Equity, closed on April 6, 2022 and expands GAI's petroleum and regulatory consulting capabilities and presence in the Texas oil & gas market.

Tailwater Capital Acquires Majority Stake in Central Midstream

December 11, 2025

Oil & Gas

Tailwater Capital has acquired a majority interest in Central Midstream Partners, LLC, a Houston-based liquids transportation, storage and terminal services provider with assets across the Gulf Coast and Ohio/Utica region. Tailwater will invest additional equity from Tailwater Fund V to support growth projects while Central Midstream CEO George Jordan and the Jordan family remain involved post-transaction.

Water Engineering Acquires Earthwise Environmental

September 20, 2023

Environmental Services

Water Engineering, a portfolio company of Nolan Capital, has acquired Earthwise Environmental, a Wood Dale, Illinois-based provider of water treatment equipment, chemicals, consultation, and preventative maintenance services. The deal is an add-on to the Water Engineering platform to expand its footprint and service capabilities across the Midwest, South and Southeast while retaining Earthwise's brand and founder Robert "Bob" Miller.