Okla. Admin. Code § 252:624-3-1

Current through Vol. 41, No. 19, June 17, 2024

Section 252:624-3-1 - Design and construction of minor public water supply system wells

(a)Licensed well driller. Minor public water supply system wells shall be drilled and completed:

(1) by a licensed well driller; and

(2) in compliance with OWRB rules.

(b)Well design. Minor public water supply system wells shall be designed and constructed in accordance with the generic plans for minor public water supply systems located in Appendix A.

(c)System capacity. The daily production capacity of the minor public water supply system shall be designed to equal or exceed the maximum daily demand.

(d)Separation distances. Minor public water supply system wells shall meet the following minimum separation distances:

(1) Fifty feet (50') from existing septic tanks and subsurface on-site sewage treatment systems. This separation distance shall be increased to one hundred feet (100') if the septic tank and/or subsurface on-site sewage treatment system is located in soil identified as:

(A) coarse sand;

(B) loamy coarse sand; or

(C) soils with a rock fragment content greater than thirty-five percent (35%) by volume having continuous voids greater than one millimeter.

(2) Fifty feet (50') from:

(A) buildings that have been treated for termites;

(B) property lines; and

(C) sewer lines. If the sewer line is Schedule 40 PVC, then the separation distance from the sewer line may be decreased to ten feet (10'); and

(3) One hundred feet (100') from petroleum underground storage tanks and all other pollution sources.

(4) Three hundred feet (300') from the outside perimeter of an existing or proposed wastewater lagoon.

(e)Approved materials. All materials that will come in contact with potable water must be approved by the NSF, UL, WSC or AWWA for use in public drinking water supplies and made of material that will not impart taste, odor, toxic substances or bacterial contamination to the water.

(f)Gravel pack. If gravel pack is used, the gravel shall be disinfected by being immersed in a chlorine solution containing not less than two hundred (200) ppm of available chlorine.

(g)Grouting requirements. Minor public water supply system wells shall be made watertight around the outside of the casing by grouting to a depth necessary to exclude pollution. In no case shall the depth of the grouting be less than twenty (20) continuous feet. The grout may be a bentonite grout, cement grout or a combination of the two. Grout must be installed so that bridging will not occur in the annular space.

(1) The cement grout shall conform to ASTM Standard C150, mixed with no more than six (6) gallons of water per ninety-four pound (94 lb.) sack of cement. When the annular space is:

(A) one and one-half inches (1.5") thick, then additives may not be used to increase the cement's fluidity without prior approval by DEQ.

(B) greater than one and one-half inches (1.5"), then sand may be added to the grout mix with a ratio of no more than one part sand to one part cement.

(C) greater than four inches (4"), then one-half inch (.5") gravel or smaller may be added to the cement grout mix.

(2) The bentonite grout shall consist of chip, chunk or pelletized bentonite varieties that are hydrated to manufacturer's specifications. If bentonite grout is used the annular space shall be a minimum of two inches (2").

(3) Where a pitless adapter or unit is being installed, the grouting shall start below the junction of the pitless well adapter or unit where it attaches to the well casing and shall continue to at least twenty feet (20') below this junction.

(h)Well screens. When well screens are used:

(1) the screens shall be constructed of materials resistant to damage by ground water or cleaning operations; and

(2) the slot size shall be selected to prevent or minimize infiltration of the filter pack through the well screen.

(i)Slab around well casing. The slab around the well casing shall:

(1) be constructed with reinforced concrete not less than three and one-half inches (3.5") thick;

(2) extend at least twelve inches (12") from the well casing in all directions;

(3) extend at least three inches (3") above the surrounding ground; and

(4) slope at least one-eighth of an inch (1/8") per foot away from the well casing.

(j)Pitless well adapters and units. A pitless well unit or pitless adapter may be used if it meets the standards of the most recent PAS-97 in a listing maintained by the WSC, and installation is performed in a manner meeting or exceeding manufacturer's installation requirements.

(k)Wellhead. The wellhead shall be constructed as follows:

(1) The well casing shall extend at least:

(A) twelve inches (12") above the concrete slab; and

(B) two feet (2') above the 100-year flood plain or the highest known flood elevation, whichever is higher.

(2) The top of the casing shall be sealed with a well seal or a cap. The well seal or cap shall be WSC approved.

(3) The discharge piping shall:

(A) be equipped with a:

(i) check valve;

(ii) shutoff valve;

(iii) pressure gauge; and

(iv) sampling tap located between the wellhead and the shutoff valve.

(B) have all exposed piping, valves and appurtenances protected against physical damage and freezing.

(C) be properly anchored to prevent movement.

(D) be protected against surge or water hammer.

(E) not be connected to any source of contamination or be configured to allow back siphonage from any source of pollution.

(4) There shall be access to disinfect the well.

(5) There shall be a properly constructed well casing vent that:

(A) vents to the atmosphere and prevents a vacuum in the well casing, unless designed for vacuum operation.

(B) is fitted into the well cap or pump base so as to form a water-tight connection.

(C) terminates in a full one hundred eighty degree (180°) bend above the top of the well casing.

(D) has a corrosion resistant screen covering the vent opening. The openings in the screen must not be larger than 24-mesh.

(l)Full-time disinfection. When disinfection is required [see 252:624-5-2 and 7-1(c) (relating to sampling and testing)], either a positive displacement hypochlorite chlorinator or an NSF approved tablet chlorinator shall be provided prior to distribution. The water supply piping for the chlorinator shall be designed to prevent back-siphonage or cross connections with non-potable water.

(m)Electrical controls. All electrical controls shall be protected from flooding.

(n)Well security. Minor public water supply systems shall be protected from vandalism, trespass and sabotage by either having:

(1) the wellhead located in a locked well house; or

(2) a locked cap on the wellhead.

Okla. Admin. Code § 252:624-3-1

Added at 25 Ok Reg 2294, eff 7-11-08

Amended by Oklahoma Register, Volume 34, Issue 24, September 1, 2017, eff. 9/15/2017