Monday, 22 January 1990
Trocadero
Philadelphia, PA, USA
supporting Voivod with Soundgarden
[No setlist details]
Confirmation:
Tour t-shirt dates (22nd Philadelphia)
CV Database
Audience recording
Soundgarden Live Guide
Voivod gig list

PattonTrader quotes this date as "January 20, 1990 Philadelphia (PA)."
http://fnm.com/trade/ quotes this date as "Bayshore, NY".
This article suggests Philly played after Boston, which would make it the 22nd.

The Philadelphia Inquirer, 24 Jan 1990, page 5D - gig review
Description:
From Soundgarden Live Guide:
"Mike Patton of Faith No More sings "I Awake" while Chris crowd surfs. At the end of Faith No More's set, Soundgarden and crew join them for a cover of Black Sabbath's "War Pigs"."
This show included a "massive food fight" - Tampa Tribune, 2 Feb 1990, page 5F
On This Day:
Year Venue State/Country
1988 Dingwalls, London England
1993 Hollywood Palladium, Los Angeles CA, USA