WAC 173-160-321
How do I test a well? (1) Well
authorized by appropriation permit - Before being put to use,
each well shall be test pumped for yield and draw down. Reports of the test pumping shall be submitted as required in
chapter 90.44 RCW. The driller shall be familiar with and
meet all testing procedures outlined in the water right
permit. The well shall be test pumped at rates equal to, or
greater than, are expected from the well during its normal
usage. The test pump for public water supply wells shall be
operated continuously for a minimum of four hours, or longer
if required by the department of health. The yield and draw
down shall be determined following at least four hours of
constant rate pumping. Periodic water level observation
should be made during draw down and subsequent recovery
periods. Periods of observation shall be more frequent during
the onset of the draw down and may decrease in frequency as
the draw down or recovery proceeds. A bailer test is not an
acceptable substitute for testing wells under permit or for
public water supply wells.
(2) Wells not requiring appropriation permit - Testing of
a well that does not require an appropriation permit shall be
conducted at a constant rate for a period of at least one hour
or longer if required by the department of health. Test
pumping under this section can be either by bailer, air lift,
or with a pump.
(3) Test data shall be reported to the department on the
water well report by the operator at the time the report is
submitted.
[Statutory Authority: Chapter 18.104 RCW. 06-23-121 (Order
06-08), § 173-160-321, filed 11/21/06, effective 12/22/06. Statutory Authority: Chapter 18.104 RCW and RCW 43.21A.080. 98-08-032 (Order 97-08), § 173-160-321, filed 3/23/98,
effective 4/23/98.]