How is the earth purified if it becomes impure with a liquid impurity like urine or wine?
Chapter on Praying with Impurity and Other Matters
Al-Mughni
Book of Prayer
Primary text
The means of purification for the earth contaminated by a liquid impurity is to flood it with water until the color and odor of the impurity disappear. Whatever water separates from it without being affected by the impurity is pure. This is the position of Al-Shafi'i. The evidence is the hadith where the Prophet (peace be upon him) commanded a large quantity of water to be poured over the place where a man urinated in the mosque. If the separated water were impure, this action would have commanded an increase in pollution, as it would have spread the impurity. The intention was solely to purify the mosque.
Supporting text
Abu Hanifa maintained that the land is not purified until the water separating from it has been poured out, meaning the separated water is impure because the impurity has transferred to it, similar to when water arrives at an impure substance. Furthermore, some narrations suggest scraping the soil first and then pouring water, but these additions are considered disconnected or weak reports.