Peninsula Energy (ASX:PEN) started the acidification process at Header House 16 within Mine Unit 4 at its Lance project in Wyoming as part of its production reset plan, according to a Thursday filing with the Australian bourse.
Header House 15 construction is on track, with acidification expected to begin in the latter part of the first quarter, the filing said.
Meanwhile, Header House 14 showed flow rates averaging 15 gallons per minute (GPM) since the start of acidification in December 2025, surpassing the reset plan assumption of 12 GPM, per the filing.
Shares rose 1% in afternoon trade on Thursday.