John Gill Commentary Nehemiah 13:9

"Then I commanded, and they cleansed the chambers: and thither brought I again the vessels of the house of God, with the meal-offerings and the frankincense." — Nehemiah 13:9 (ASV)

Then I commanded, and they cleansed the chambers
By which it appears there were more than one, or that several were thrown into one; which was done not only by washing them, but as this was a ceremonial uncleanness, contracted by the habitation of an Heathen in them, their purification might be by the water of separation, (Numbers 19:9)

and thither brought I again the vessels of the house of God, with the
meat offering and the frankincense ;
replaced them where they were before.