Terumos11: 6
מְגוּרָה שֶׁפִּנָּה מִמֶּנָּה חִטֵּי תְרוּמָה, אֵין מְחַיְּבִין אוֹתוֹ לִהְיוֹת יוֹשֵׁב וּמְלַקֵּט אַחַת אַחַת; אֶלָּא מְכַבֵּד כְּדַרְכּוֹ, וְנוֹתֵן לְתוֹכָהּ חֻלִּין.
A storeroom from which one cleared out wheat of terumah, we do not obligate him to sit and pick up [kernels of the terumah wheat] one by one; rather, he sweeps [the storeroom] as is his [usual] way, and puts chullin into it.