Staple your homework! or 10 pts off.

EART 10 - Geologic Principles		NAME_____________________
Fall 1995		

DARCY'S LAW
due date:  November 9, 1995

Coefficient of permeability (K) for some rock types:
	igneous rock, unfractured	1 x 10-10 cm/s
	igneous rock, fractured		1 x 10-3 cm/s
	sandstone			1 x 10-6 cm/s



A person illegally dumps a large quantity of pollutant at point A in the figure
above.  For the following problems, assume that groundwater flows parallel to
the hillside.  Give answers for rates in cm/s and for time in years.  Show all work
on a separate piece of paper that you will turn in with this answer sheet.

PART A	Calculate the rate of flow (Q/A) and how long (t) it will take the
pollutant to travel to point B if the hillside is composed of:
	1.  unfracture igneous rock
	2.  fractured igneous rock
	3.  sandstone
Show your work on a separate paper and put your answers in the table below.

		unfractured 		fractured		sandstone
		igneous rock		igneous rock

Q/A (cm/s)	__________		__________		_________

t (years)	__________		__________		__________



What is the effect of rock permeability (K) on the rate of flow?

_____________________________________________________________

_____________________________________________________________


PART B	Calculate the rate of flow (Q/A) and the time (t) it takes the
pollutant to travel to point B through sandstone given that the slope of the angle
ABC is:
	1.  14.0 degrees
	2.  26.6 degrees
	3.  36.9 degrees
Show your work on a separate paper and put your answers in the table below. 
Note:  Length B-C is constant, however length A-C will vary with slope.

			14.0 degrees	26.6 degrees	36.9 degrees

Q/A (cm/s)		______		_____		_____

t (years)		______		_____		_____


What is the effect of slope (hydraulic gradient) on the rate of flow?

____________________________________________________________


____________________________________________________________