Loading (50 kb)...'
(continued) dimensions to enable observation of soil characteristics by visual and tactile means to a depth three feet deeper than the anticipated bottom of the disposal component; or
(B) Stopping at a shallower depth if a water table or restrictive layer is encountered; and
(ii) Allow determination of the soil's texture, structure, color, bulk density or compaction, water absorption capabilities or permeability, and elevation of the highest seasonal water table; and
(b) Assume responsibility for constructing and maintaining the soil log excavation in a manner to reduce potential for physical injury by:
(i) Placing excavated soil no closer than two feet of the excavation;
(ii) Providing a ladder, earth ramp or steps for safe egress to a depth of four feet, then scoop out a portion from the floor to gain the additional two foot depth necessary to observe the six feet of soil face, however the scooped portion is not to be entered;
(iii) Provide a physical warning barrier around the excavation's perimeter; and
(iv) Fill the excavation upon completion of the soil log.
(4) The local health officer:
(a) Shall render a decision on the height of the water table within twelve months of receiving the application under precipitation conditions typical for the region;
(b) May require water table measurements to be recorded during months of probable high-water table conditions, if insufficient information is available to determine the highest seasonal water table;
(c) May require any other soil and site information affecting location, design, or installation; and
(d) May reduce the required number of soil logs for OSS serving a single family residence if adequate soils information has previously been developed.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-11001, filed 4/15/94, effective 1/1/95.]
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246-272-11501
Design.
(1) The local health officer shall require that on-site sewage systems be designed only by engineers or qualified designers, except:
(a) Where at the discretion of the local health officer a resident owner of the single family residence is allowed to design a system for that residence; or
(b) The local health officer performs the soil and site evaluation and develops the design.
(2) The local health officer and the department shall require the following design criteria:
(a) All the sewage from the building served is directed to the OSS;
(b) Drainage from the surface, footing drains, roof drains, and other nonsewage drains is prevented from entering the OSS and the area where the OSS is located;
(c) The OSS is designed to treat and dispose of the following flows:
(i) For single family residences, one hundred twenty gallons per bedroom per day, with a minimum of two hundred forty gallons per day, unless technical justification is provided to support calculations using a lower design flow;
(ii) For other facilities, the design flows noted in "Design Manual: On-site Wastewater Treatment and Disposal Systems," United States Environmental Protection Agency, EPA-625/1-80-012, October, 1980 (available upon written request to the department.) If the type of facility is not listed in the EPA design manual, design flows from one of the following documents are used:
(A) "Design Standards for Large On-site Sewage Systems," 1993, Washington state department of health (available upon request to the department); or
(B) "Criteria for Sewage Works Design," revised October 1985, Washington state department of ecology (available upon written request to the department of ecology).
(d) Septic tanks:
(i) Are included on the approved list under subsection (5)(d) of this section;
(ii) Have the following minimum liquid capacities:
(A) For a single family residence use Table III, Required Minimum Liquid Volumes of Septic Tanks:
TABLE III
REQUIRED MINIMUM LIQUID VOLUMES OF SEPTIC TANKS
Number of bedrooms Required minimum liquid
tank volume in gallons
< 3 900
4 1000
Each additional bedroom 250
(B) For facilities handling residential sewage, other than one single family residence, one and one-half times the daily design flow with a minimum of one thousand gallons;
(iii) Have clean-out and inspection accesses within twelve inches of finished grade; and
(iv) Are designed with protection against floatation and ground water intrusion in high ground water areas;
(e) Pump chambers:
(i) Are included on the approved list under subsection (5)(d) of this section;
(ii) Have clean-out and inspection accesses at or above finished grade; and
(iii) Are designed with protection against floatation, ground water intrusion, and surface water inflow in high ground water areas;
(f) Methods for effluent distribution shall correlate to soil types 1A through soil type 6 as described by Table IV of this section, except where local regulations approved by the department under WAC 246-272-02001 are more stringent:
TABLE IV
METHODS OF EFFLUENT DISTRIBUTION FOR SOIL TYPES AND DEPTHS
VERTICAL SEPARATION
SOIL
TYPE < 1 foot > 1 foot to
< 2 feet > 2 feet to
< 3 feet > 3 feet
1A Not
allowed Pressure
Distribution
(see note)1&2 Pressure
Distribution
(see note)1 Pressure
Distribution
(see note)1
2A Not
allowed Pressure
Distribution
(see note)1&2 Pressure
Distribution Pressure
Distribution
1B -6 Not
allowed Pressure
Distribution
(see note)1&2 Pressure
Distribution Gravity
Distribution
1 System meeting Treatment Standard 2 required.
2 Mound systems installed where the original, undisturbed, unsaturated soil depth is between twelve and eighteen inches, require pretreatment by an intermittent sand filter.
(g) SSAS beds are only designed in soil types 2A, 2B, or 3, with a width not exceeding ten feet;
(h) Designs for conventional gravity systems in type 1A soil are not permitted due to the inadequate treatment performance capability of coarse grained soils. However, an exception may be permitted by the local health officer if the site meets all of the following criteria:
(i) System serves a single family residence;
(ii) The lot size is greater than two and one-half acres;
(iii) Annual precipitation in the region is less than twenty-five inches per year as described by "Washington Climate" published jointly by the Cooperative Extension Service, College of Agriculture, and Washington State University (available for inspection at Washington state libraries);
(iv) The system is located outside all areas of special concern defined by WAC 246-272-21501(1);
(v) The system is located outside the twelve county Puget Sound water quality authority region; and
(vi) The geologic conditions beneath the disposal component must satisfy the minimum unsaturated depth requirements to ground water identified by interpreting a readable, representative well log. The method for determination is described by "Design Guideline for Conventional Gravity Systems In Soil Type 1," (available upon written request to the department).
(i) Individual SSAS laterals greater than one hundred feet in length are to use pressure distribution;
(j) OSS having daily design flows between one thousand and three thousand five hundred gallons of sewage per day:
(i) Are located only in soil types 1 - 5;
(ii) Are located on slopes of less than thirty percent, or seventeen degrees; and
(iii) Have pressure distribution;
(k) Conventional gravity systems and conventional pressure distribution system have:
(i) The calculation of absorption area based upon the design flows in (c) of this subsection and loading rates equal to or less than those in Table V, Maximum hydraulic loading rate for residential sewage, and applied only to the bottom of the trench of the excavation.
TABLE V
MAXIMUM HYDRAULIC LOADING RATE
FOR RESIDENTIAL SEWAGE1
SOIL
TYPE SOIL TEXTURAL CLASSIFICATION DESCRIPTION LOADING RATE
gal./sq. ft./day
1A Very gravelly2 coarse sands or coarser, extremely gravelly3 soils. Varies according to system selected to meet Treatment Standard 24
1B Very gravelly medium sands, very gravelly fine sands, very gravelly very fine sands, very gravelly loamy sands. Varies according to soil type of the non-gravel portion5
2A Coarse sands (includes the ASTM C-33 sand). 1.2
2B Medium sands. 1.0
3 Fine sands, loamy coarse sands, loamy medium sands. 0.8
4 Very fine sands, loamy fine sands, loamy very fine sands, sandy loams, loams. 0.6
5 Silt loams that are porous and have well developed structure. 0.45
6 Other silt loams, sandy clay loams, clay loams, silty clay loams. 0.2
1 Compacted soils, cemented soils, and/or poor soil structure may require a reduction of the loading rate or make the soil unsuitable for conventional OSS systems.
2 Very gravelly = >35% and <60% gravel and coarse fragments, by volume.
3 Extremely gravelly = >60% gravel and coarse fragments, by volume.
4 Due to the highly permeable nature of type 1A soil, only alternative systems which meet or exceed Treatment Standard 2 can be installed. However, a conventional gravity system may be used if it meets all criteria listed under (h) of this subsection. The loading rate for these systems is provided in the appropriate guideline.
5 The maximum loading rate listed for the soil described as the nongravel portion is to be used for calculating the absorption surface area required. The value is to be determined from this table.
(ii) The bottom of a SSAS shall not be deeper than three feet below the finished grade, except under special conditions approved by the local health officer. The depth of such system shall not exceed ten feet from the finished grade;
(iii) The sidewall below the invert of the distribution pipe is located in original, undisturbed soil;
(iv) Clean gravel, covered with a geotextile; and
(v) A cover of between six and twenty-four inches of mineral soil containing no greater than ten percent organic content over the gravel to preclude accumulation of water over the drainfield.
(l) For other features, conventional gravity systems shall conform with the "Design Manual: On-site Wastewater Treatment and Disposal Systems," United States Environmental Protection Agency, EPA-625/1-80-012, October, 1980 (available upon written request to the department) except where modified by, or in conflict with this section or local regulations.
(3) When proposing the use of OSS for nonresidential sewage, the designer shall provide to the local health officer:
(a) Information to show the sewage is not industrial wastewater;
(b) Information to establish the sewage's strength and identify chemicals found in the sewage that are not found in residential sewage; and
(c) A design providing treatment equal to that required of residential sewage.
(4) The local health officer or department:
(a) Shall approve only OSS designs meeting the requirements of this chapter;
(b) Shall only permit the use of septic tanks, pump chambers, and holding tanks on the approved list under subsection (5)(d) of this section;
(c) Shall not approve designs for:
(i) Cesspools;
(ii) Seepage pits, except as allowed for repairs under WAC 246-272-16501(3); or
(iii) Conventional gravity systems or conventional pressure distribution systems in soil type 1A, except when an applicant meets all criteria established by subsection (2)(h) of this section.
(d) May approve a design for the reserve area different than the design approved for the initial OSS, if both designs meet the requirements of this chapter for new construction; and
(e) May allow the hydraulic loading rate calculated for the infiltration surface area in a disposal component to include six inches of the SSAS sidewall height for determining design flow where total recharge by annual precipitation and irrigation is less than twelve inches per year.
(5) The department shall:
(a) Develop and maintain design and construction standards for septic tanks, pump chambers, and holding tanks.
(b) Review septic tanks, pump chambers, and holding tanks, approving those satisfying the design and construction standards developed by the department.
(c) Require an annual report from the manufacturers or distributors of all products on the approved list under (d) of this subsection which assures that the product still meets the standards defined in this section, before relisting the product.
(d) Maintain a list of approved septic tanks, pump chambers, holding tanks that meet design and construction standards.
(e) Make periodic checks of products approved under this subsection.
(6) Persons desiring to manufacture or distribute septic tanks, pump chambers, holding tanks for use in an OSS shall:
(a) Certify the product meets standards for subsection (5)(a) of this section and submit the required documentation to the department for approval when:
(i) The manufacturer or distributor needs initial departmental review and listing to allow permitting by the local health officer or department;
(ii) The department amends the applicable criteria or standards; or
(iii) The manufacturer or distributor alters the product;
(b) Submit an annual report acceptable to the department to retain departmental approval; and
(c) Pay required fees to the department.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-11501, filed 4/15/94, effective 1/1/95.]
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246-272-12501
Holding tank sewage systems.
(1) Persons shall not install or use holding tank sewage systems for residential development or expansion of residences, whether seasonal or year-round, except as set forth under subsection (2) of this section.
(2) The local health officer may approve installation of holding tank sewage systems only:
(a) For permanent uses limited to controlled, part-time, commercial usage situations, such as, recreational vehicle parks and trailer dump stations.
(b) For interim uses limited to handling of emergency situations.
(c) For repairs as permitted under WAC 246-272-16501 (1)(c)(i).
(3) A person proposing to use a holding tank sewage system shall:
(a) Follow established design criteria established by the department;
(b) Submit a management program to the local health officer assuring ongoing operation and maintenance before the local health officer issues the installation permit; and
(c) Use a holding tank on the current approved list under WAC 246-272-11501 (5)(d).
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-12501, filed 4/15/94, effective 1/1/95.]
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246-272-13501
Installation.
(1) The local health officer and the department shall require approved installers to construct OSS, except as noted under subsection (2) of this section.
(2) The local health officer may allow the resident owner of a single family residence to install the OSS for that single family residence when: The OSS is either located on the same lot as the residence or situated on adjoining property controlled by the owner and legally listed as an encumbrance.
(3) The installer described by either subsection (1) or (2) of this section shall:
(a) Follow the approved design;
(b) Have the approved design in possession during installation;
(c) Only install septic tanks, pump chambers, and holding tanks approved by the department;
(d) Be on the site at all times during the excavation and construction of the OSS;
(e) Install the OSS to be watertight, except for the disposal component;
(f) Cover the installation only after the local health officer has given approval to cover; and
(g) Back fill and grade the site to prevent surface water from accumulating over any component of the OSS.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-13501, filed 4/15/94, effective 1/1/95.]
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246-272-14501
Inspection.
(1) The local health officer shall:
(a) Visit the OSS site during the site evaluation, construction, or final construction inspection;
(b) Either inspect the OSS before cover or allow the designer of the OSS to perform the inspection before cover if:
(i) The designer is qualified; and
(ii) The designer is not also named as installer of the system; and
(iii) A qualified installer installed the OSS.
(c) Keep the "as-built" or "record" drawings on file.
(2) The person responsible for the final construction inspection shall:
(a) Assure the OSS meets the approved design; and
(b) Direct the person responsible for final cover of the system to place a permanent marker at finished grade where needed to identify the location of the septic tank's first manhole.
(3) The designer or installer, as directed by the local health officer, upon completion of the OSS shall develop and submit a complete and detailed, "as-built" or "record drawing" to both the health officer and the OSS owner that include:
(a) For new OSS, measurements to existing site features enabling the first tank manhole to be easily located, and a dimensioned reserve area; and
(b) For repaired or altered OSS, the new, repaired, or altered components with their relationship to the existing system.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-14501, filed 4/15/94, effective 1/1/95.]
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246-272-15501
Operation and maintenance.
(1) The OSS owner is responsible for properly operating and maintaining the OSS, and shall:
(a) Determine the level of solids and scum in the septic tank once every three years;
(b) Employ an approved pumper to remove the septage from the tank when the level of solids and scum indicates that removal is necessary;
(c) Protect the OSS area and the reserve area from:
(i) Cover by structures or impervious material;
(ii) Surface drainage;
(iii) Soil compaction, for example by vehicular traffic or livestock; and
(iv) Damage by soil removal and grade alteration;
(d) Keep the flow of sewage to the OSS at or below the approved design both in quantity and waste strength;
(e) Operate and maintain alternative systems as directed by the local health officer; and
(f) Direct drains, such as footing or roof drains, away from the area where the OSS is located.
(2) The local health officer shall:
(a) Provide operation and maintenance information to the OSS owner upon approval of any installation, repair, or alteration of an OSS; and
(b) Develop and implement plans to:
(i) Monitor all OSS performance within areas of special concern;
(ii) Initiate periodic monitoring of each OSS no later than January 1, 2000, to assure that each OSS owner properly maintains and operates the OSS in accordance with this section and in accordance with other applicable operation and maintenance requirements.
(iii) Disseminate relevant operation and maintenance information to OSS owners through effective means routinely and upon request; and
(iv) Assist in distributing educational materials to OSS owners.
(3) Persons shall not:
(a) Use or introduce strong bases, acids or chlorinated organic solvents into an OSS for the purpose of system cleaning;
(b) Use a sewage system additive unless it is specifically approved by the department; or
(c) Use an OSS to dispose of waste components atypical of residential wastewater.
(4) The local health officer shall require annual inspections of OSS serving food service establishments and may require pumping as needed.
(5) The local health officer may require the owner of the OSS to:
(a) Use one or more of the following management methods or another method consistent with the following management methods for proper operation and maintenance:
(i) Obtain and comply with the conditions of a renewable or operational permit;
(ii) Employ a public entity eligible under Washington state statutes to, directly or indirectly, manage the OSS; or
(iii) Employ a private management entity, guaranteed by a public entity eligible under Washington state statutes or sufficient financial resources, to manage the OSS;
(b) Evaluate any effects the OSS may have on ground water or surface water; and/or
(c) Dedicate easements for inspections, maintenance, and potential future expansion of the OSS.
(6) Persons may obtain a handbook with material outlining management methods to achieve proper operation, maintenance, and monitoring of OSS from the department one year after the effective date of this chapter.
(7) The local health officer may require installation of observation ports in each individual lateral or bed which extend from the bottom of the gravel to the finished grade for monitoring OSS performance.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-15501, filed 4/15/94, effective 1/1/95.]
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246-272-16501
Repair of failures.
(1) When an OSS failure occurs, the OSS owner shall:
(a) Repair or replace the OSS with a conforming system or a Table VI repair either on the:
(i) Property served; or
(ii) Nearby or adjacent property if easements are obtained; or
(b) Connect the residence or facility to a:
(i) Publicly owned LOSS; or
(ii) Privately owned LOSS where it is deemed economically feasible; or
(iii) Public sewer; or
(c) Perform one of the following when requirements in (a) or (b) of this subsection are not feasible:
(i) Use a holding tank; or
(ii) Obtain a National Pollution Discharge Elimination System or state discharge permit from the Washington state department of ecology issued to a public entity or jointly to a public entity and the system owner only when the local health officer determines:
(A) An OSS is not feasible; and
(B) The only realistic method of final disposal of treated effluent is discharge to the surface of the land or into surface water; or
(iii) Abandon the property.
(2) Prior to replacing or repairing the effluent disposal component, the OSS owner shall develop and submit information required under WAC 246-272-09001(1).
(3) The local health officer shall permit a Table VI repair only when:
(a) Installation of a conforming system is not possible; and
(b) Connection to either an approved LOSS or a public sewer is not feasible.
(4) The person responsible for the design shall locate and design repairs to:
(a) Meet the requirements of Table VI if the effluent treatment and disposal component to be repaired or replaced is closer to any surface water, well, or spring that is not used as a public water source as prescribed by the minimum separation required in Table 1 of WAC 246-272-09501(1);
TABLE VI
REQUIREMENTS FOR REPAIR OR REPLACEMENT OF DISPOSAL COMPONENTS NOT MEETING VERTICAL
AND HORIZONTAL SEPARATIONS 1,2
Vertical
Separation in
feet Horizontal Separation in Feet3
< 25 25 - 50 > 50 - <100
<1 Treatment
Standard 1 Treatment
Standard 1 Treatment
Standard 24
1 - 2 Treatment
Standard 1 Treatment
Standard 24 Pressure
Distribution
>2 Treatment
Standard 24 Pressure
Distribution Pressure
Distribution
1 The treatment standards refer to effluent quality before discharge to unsaturated, subsurface soil.
2 The local health officer may permit ASTM C-33 sand to be used as fill to prevent direct discharge of treated effluent to ground water, surface water, or upon the surface of the ground.
3 The horizontal separation indicated is the distance between the disposal component and the surface water, well, or spring. If the disposal component is up-gradient of a surface water, well, or spring to be used as a potable water source, the next higher standard level of treatment shall apply unless treatment standard 1 is already being met.
4 Mound systems are not allowed to meet treatment standard 2.
(b) Protect drinking water sources;
(c) Prevent the direct discharge of sewage to ground water, surface water, or upon the surface of the ground;
(d) Meet the horizontal separations under WAC 246-272-09501(1) to public drinking water sources;
(e) Meet other requirements of this chapter to the maximum extent permitted by the site;
(f) Maximize the:
(i) Vertical separation;
(ii) Distance from a well, spring, or suction line; and
(iii) Distance to surface water.
(5) The local health officer shall identify Table VI repair permits for the purpose of tracking future performance.
(6) An OSS owner receiving a Table VI repair permit from the local health officer shall:
(a) Immediately report any failure to the local health officer;
(b) Monitor the performance of the OSS according to the "Interim Guidelines for the Application of Treatment Standards 1 & 2, using Alternative On-site Sewage Treatment/Disposal Systems" amended August 4, 1992, (available upon written request to the department of health) and report the results to the local health officer at a minimum frequency of:
(i) Quarterly when treatment standard 1 is required; and
(ii) Annually when treatment standard 2 is required;
(c) Comply with all local and state requirements stipulated on the permit.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-16501, filed 4/15/94, effective 1/1/95.]
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246-272-17501
Expansions.
The local health officer or department shall require an on-site sewage system and a reserve area in full compliance with the new system construction standards specified in this chapter for an expansion of a residence or other facility.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-17501, filed 4/15/94, effective 1/1/95.]
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246-272-18501
Abandonment.
Persons permanently removing a septic tank, seepage pit, cesspool, or other sewage container from service shall:
(1) Have the septage removed by an approved pumper;
(2) Remove or destroy the lid; and
(3) Fill the void with soil.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-18501, filed 4/15/94, effective 1/1/95.]
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246-272-19501
Septage management.
(1) An individual shall be approved by the local health officer as a qualified pumper before removing septage from an OSS.
(2) Persons removing septage from an OSS shall:
(a) Transport septage or sewage only in vehicles clearly identified with the name of the business and approved by the local health officer;
(b) Record and report septage removal to the local health officer;
(c) Dispose of septage, or apply septage biosolids to land only in a manner consistent with applicable laws.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-19501, filed 4/15/94, effective 1/1/95.]
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246-272-20501
Developments, subdivisions, and minimum land area requirements.
(1) A person proposing the development shall obtain approval from the local health officer prior to any development where the use of OSS is proposed.
(2) The local health officer shall require the following prior to approving any development:
(a) Site evaluations as required under WAC 246-272-11001, excluding subsections (3)(a)(i) and (4)(d);
(b) Where a subdivision with individual wells is proposed:
(i) Configuration of each lot to allow a one hundred-foot radius water supply protection zone to fit within the lot lines; or
(ii) Establishment of a one hundred-foot protection zone around each existing and proposed well site;
(c) Where preliminary approval of a subdivision is requested, provision of at least one soil log per proposed lot, unless the local health officer determines existing soils information allows fewer soil logs;
(d) Determination of the minimum lot size or minimum land area required for the development using Method I and/or Method II:
(i) METHOD I. Table VII, Single family residence minimum lot size or minimum land area required per unit volume of sewage, shows the minimum lot size required per single family residence. For developments other than single family residences, the minimum land areas shown are required for each unit volume of sewage.
TABLE VII
MINIMUM LAND AREA REQUIREMENT
SINGLE FAMILY RESIDENCE OR UNIT VOLUME OF SEWAGE
Type of
Water Supply Soil Type (defined by section 11001 of this chapter)
1A, 1B 2A, 2B 3 4 5 6
Public 0.5 acre1 12,500
sq. ft. 15,000
sq. ft. 18,000
sq. ft. 20,000
sq. ft. 22,000
sq. ft.
2.5 acre2
Individual,
on each lot 1 acre1 1 acre 1 acre 1 acre 2 acres 2 acres
2.5 acres2
1 Due to the highly permeable nature of type 1 soil, only alternative systems which meet or exceed Treatment Standard 2 can be installed.
2 A conventional gravity system in type 1 soil is only allowed if it is in compliance with all conditions listed under WAC 246-272-11501 (2)(h). One of these limiting conditions is a 2.5 acre minimum lot size.
(ii) METHOD II. A minimum land area proposal using Method II is acceptable only when the applicant:
(A) Justifies the proposal through a written analysis of the:
(I) Soil type and depth;
(II) Area drainage, and/or lot drainage;
(III) Public health impact on ground and surface water quality;
(IV) Setbacks from property lines, water supplies, etc.;
(V) Source of domestic water;
(VI) Topography, geology, and ground cover;
(VII) Climatic conditions;
(VIII) Availability of public sewers;
(IX) Activity or land use, present, and anticipated;
(X) Growth patterns;
(XI) Reserve areas for additional subsurface treatment and disposal;
(XII) Anticipated sewage volume;
(XIII) Compliance with current planning and zoning requirements;
(XIV) Possible use of alternative systems or designs;
(XV) Existing encumbrances, such as listed in WAC 246-272-09001 (1)(c)(v) and 246-272-11001 (2)(a)(vii); and
(XVI) Any other information required by the local health officer.
(B) Shows development with public water supplies having:
(I) At least twelve thousand five hundred square feet lot sizes per single family residence;
(II) No more than 3.5 unit volumes of sewage per day per acre for developments other than single family residences; and
(C) Shows development with individual water supplies having at least one acre per unit volume of sewage; and
(D) Shows land area under surface water is not included in the minimum land area calculation; and
(e) Regardless of which method is used for determining required minimum lot sizes or minimum land area, submittal to the health officer of information consisting of field data, plans, and reports supporting a conclusion the land area provided is sufficient to:
(i) Install conforming OSS;
(ii) Assure preservation of reserve areas for proposed and existing OSS;
(iii) Properly treat and dispose of the sewage; and
(iv) Minimize public health effects from the accumulation of contaminants in surface and ground water.
(3) The local health officer shall require lot areas of twelve thousand five hundred square feet or larger except when a person proposes:
(a) OSS within the boundaries of a recognized sewer utility having a finalized assessment roll; or
(b) A planned unit development with:
(i) A signed, notarized, and recorded deed covenant restricting any development of lots or parcels above the approved density with the density meeting the minimum land area requirements of subsection (2)(d) of this section;
(ii) A public entity responsible for operation and maintenance of the OSS, or a single individual owning the OSS;
(iii) Management requirements under WAC 246-272-08001 when installing a LOSS; and
(iv) Extinguishment of the deed covenant and higher density development allowed only when the development connects to public sewers.
(4) The local health officer may:
(a) Allow inclusion of the area to the centerline of a road or street right of way in a Method II determination under subsection (2)(d)(ii) of this section to be included in the minimum land area calculation if:
(i) The dedicated road or street right of ways are along the perimeter of the development;
(ii) The road or street right of ways are dedicated as part of the proposed development; and
(iii) Lots are at least twelve thousand five hundred square feet in size.
(b) Require detailed plot plans and OSS designs prior to final approval of subdivision proposals;
(c) Require larger land areas or lot sizes to achieve public health protection;
(d) Prohibit development on individual lots within the boundaries of an approved subdivision if the proposed OSS design does not protect public health by meeting requirements of these regulations; and
(e) Permit the installation of an OSS, where the minimum land area requirements or lot sizes cannot be met, only when all of the following criteria are met:
(i) The lot is registered as a legal lot of record created prior to the effective date of this chapter;
(ii) The lot is outside an area of special concern where minimum land area has been listed as a design parameter necessary for public health protection; and
(iii) The proposed system meets all requirements of these regulations other than minimum land area.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-20501, filed 4/15/94, effective 1/1/95.]
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246-272-22501
Certification of designers, installers, pumpers, inspectors, and maintenance personnel.
Guidelines defining qualifications for designers, installers, pumpers, inspectors and maintenance personnel shall be established by the department. The guidelines shall include, but not be limited to education, experience, testing, and certification.
[Statutory Authority: RCW 43.20.050. 94-09-025, § 246-272-22501, filed 4/15/94, effective 1/1/95.]
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246-272-990
Fees.
(1) The minimum fee for required review of larger on-site system's engineering reports and plans and specifications shall be four hundred dollars. If review time exceeds eight hours, fifty dollars for each additional hour or part of an hour shall be added to the minimum fee. The fee for pre-site inspections for larger on-site systems shall be one hundred dollars per visit. The fee for final inspection of larger on-site systems shall be one hundred dollars per site visit.
(2) The minimum fee for required review of proprietary devices shall be two hundred dollars. If review time exceeds four hours, fifty dollars for each additional hour or part of an hour shall be added to the minimum fee.
(3) The minimum fee for required review of experimental systems shall be four hundred dollars. If review time exceeds eight hours, fifty dollars for each additional hour or part of an hour shall be added to the minimum fee.
[Statutory Authority: RCW 43.70.040. 91-02-050 (Order 122), § 246-272-990, filed 12/27/90, effective 1/31/91.]