Deuteronomy 21:4

21:4 and bring the heifer down to a wadi with flowing water, ¹  to a valley that is neither plowed nor sown. ²  There at the wadi they are to break the heifer’s neck.

Deuteronomy 21:6

21:6 and all the elders of that city nearest the corpse ³  must wash their hands over the heifer whose neck was broken in the valley. ⁴ 

[21:4]  ¹ tn The combination “a wadi with flowing water” is necessary because a wadi (נַחַל, nakhal) was ordinarily a dry stream or riverbed. For this ritual, however, a perennial stream must be chosen so that there would be fresh, rushing water.

[21:4]  ² sn The unworked heifer, fresh stream, and uncultivated valley speak of ritual purity – of freedom from human contamination.

[21:6]  ³ tn Heb “slain [one].”

[21:6]  ⁴ tn Heb “wadi,” a seasonal watercourse through a valley.