McKesson Corporation is conducting an environmental investigation under the oversight of the San Francisco Regional Water Quality Control Board (Water Board) in the area where the company operated a chemical distribution and repackaging facility from 1971 to 1986 at 33950 Seventh Street in Union City.

Past operations left chemicals called volatile organic compounds (VOCs) in soil and groundwater.  VOCs that evaporate from polluted soil and groundwater can create chemical vapors underground (called soil vapor). Under some circumstances, soil vapor can move underneath a building and enter indoor air through cracks in the building foundation, around pipes, or through a drain system. The VOCs can then negatively impact the quality of indoor air. This process - when pollution moves from air spaces in soil to indoor air - is called vapor intrusion.

Beginning in fall 2021, McKesson will be conducting indoor air testing within select homes and commercial properties to evaluate if vapor intrusion is occurring. Contractors working for McKesson will also collect samples of soil gas from public rights-of-way and of outdoor air.  This information will be used to determine next steps in the investigation process.

We are currently developing this website which will have more information on the site history, environmental investigations, community outreach, and key project documents. Please check back soon.

If you have any questions, we encourage you to visit the Water Board’s project website or contact our toll-free information line at (877) 326-3796 or info@McKessonUC.com. Thank you.

• Project Fact Sheet

• Water Board Vapor Intrusion Fact Sheet