That portion of the eastern boundary line of the county of Gilpin and that portion of the western boundary line of the county of Jefferson lying between the northwest corner of the county of Jefferson and the junction of the North and South Clear creeks, is fixed and established as follows:
Beginning at a certain point on the north line of township two south, range seventy-two west of the sixth principal meridian, which point is due north of the junction of the North and South Clear creeks; thence due south to the junction of the North and South Clear creeks; but Jefferson county shall not be liable for any taxes already collected on lands lying west of the boundary hereby established.
C.R.S. § 30-5-127