Washington Administrative Code › Title 173 - Ecology, Department of (See also Titles 197, 317, 372, and 508) › Chapter 173-160 - Minimum standards for construction and maintenance of wells › Part ONE - GENERAL REQUIREMENTS FOR WATER WELL CONSTRUCTIO › Section 173-160-331 - How do I make sure my equipment and the water well are free of contaminants?

Current through Register Vol. 24-14, July 15, 2024
(1)
				All tools, drilling equipment and materials shall be free of contaminants prior
				to beginning well construction. Contaminants include lubricants, fuel, bacteria
				that will reduce the well efficiency, and any other item(s) that will be
				harmful to public health and/or the resource or reduce the life of the water
				well.
(2) Every new or
				reconditioned water well, after completion of construction or repair, and
				before being placed in service, shall be cleared of all foreign materials, and
				free of contamination.
(3) The well
				casing shall be swabbed and cleaned to remove oil, grease or joint
				dope.
(4) All pumping equipment,
				sand or gravel used in gravel-packed water wells and the well casing shall be
				thoroughly sluiced with clean water and disinfected. The disinfecting agent
				shall be safe and not impair the potability of the groundwater. All
				disinfectants shall be used in accordance with manufacturer's
				recommendations.
(5) Before the
				well is put to use, the standing water in the well shall be disinfected and
				flushed to remove all traces of disinfectant. A water sample may then be taken
				and tested for coliform bacteria or other items required by the state
				department of health or local health authority. Examples of other test items
				may include: Nitrates, dissolved solids, sodium, iron, pH, manganese,
				conductivity, hardness, and turbidity. If testing indicates a presence of
				coliform bacteria, more stringent disinfecting methods may be required by the
				department of health or local health authority.
If chlorine is used to disinfect the well water, sufficient
				  chlorine will be added to the standing water to give a residual of fifty ppm
				  free chlorine. The chlorine shall remain in the well for a period of at least
				  twenty-four hours. After twenty-four hours, a minimum of one ppm free chlorine
				  residual shall remain in the water before the well is flushed free of chlorine
				  and a sample taken. Other disinfectants placed in the groundwater shall be used
				  in quantities that are safe, nonpolluting, and that are not a detriment to the
				  potability of the groundwater. All disinfectants used in groundwater shall be
				  used in accordance with manufacturer's recommendations.
(6) Chlorine and other disinfectants can
				pollute. Allow the chlorine or other disinfectants in the rinse water to
				dissipate before discharging the water to surface water. This water shall be
				discharged in a safe manner consistent with the intent of the Water Pollution
				Control Act,
				chapter
				90.48 RCW.
Statutory Authority: Chapter 18.104 RCW and
					 RCW
					 43.21A.080. 98-08-032 (Order 97-08), §
					 173-160-331, filed 3/23/98, effective
					 4/23/98.