San Mateo County Municipal Code Art. 5 Alternative Owts

a. Types of alternative OWTS permitted, consisting of supplemental treatment systems and/or alternative dispersal systems, shall be limited to those systems identified in the Onsite Systems Manual, and which have been approved by Environmental Health and the appropriate CRWQCB.

b. Supplemental treatment systems may be used to produce higher quality of wastewater effluent beyond that provided by a conventional septic tank and improve the performance of and siting options for the dispersal system.

c. Alternative OWTS, utilizing supplemental treatment of effluent, may be required by Environmental Health for any new construction or repair within designated impaired areas as described in article 6 of this chapter.

d. Alternative OWTS, including supplemental treatment of effluent and/or pressure-dosing distribution, may be required by Environmental Health for any new construction or repair where three (3)-foot separation from base of distribution to groundwater was previously investigated and approved by Environmental Health prior to the effective date of this chapter, as described in section 4.84.165 of this chapter.

e. Alternative OWTS consisting of pressure-dosing distribution dispersal systems shall be required on slopes exceeding thirty-five percent (35%), and for areas with average soil percolation rate between 0.75 and 1.0 inches per hour.

f. All alternative dispersal systems installed in San Mateo County must be below-grade systems.

g. Alternative OWTS may be permitted by Environmental Health for the repair or upgrading of any existing OWTS where it is determined that sewage cannot be disposed of in a sanitary manner by a conventional septic tank and gravity flow dispersal field system.

h. All alternative systems shall be installed by a contractor duly licensed by the Contractors State License Board of the State of California to install OWTS. Where the installation includes a proprietary treatment system, the contractor shall also possess any required manufacturer certifications, as applicable.

i. Notwithstanding any other provisions of this section, Environmental Health shall have the authority to deny and/or require modifications to any alternative OWTS proposal where it determines that such proposal poses an unacceptable threat to public health and/or water quality. Any such denial of a Permit shall be in accordance with section 4.84.085 of this chapter.

j. Alternative OWTS utilizing shallow subsurface drip dispersal may be permitted by Environmental Health for new construction on any legally-created parcel where Environmental Health determines such system would provide equal or greater protection to public health and the environment than a conventional or trench-based pressure-dosing distribution dispersal system. However, both a primary and reserve dispersal system for a conventional or trench-based pressure-dosing distribution dispersal system shall be designed, area reserved and such system could still be installed, if required. The area of the installed shallow subsurface drip dispersal system and the reserved conventional or trench-based pressure-dosing distribution dispersal system can overlap as long as the operation of the shallow drip dispersal system will not affect the potential future function of trench-based dispersal system.

k. All Alternative OWTS must comply with the specific requirements set forth in this section and the Onsite Systems Manual.

(Ord. No. 04754, § 1, 1-5-2016)

a. Engineering plans and site data for alternative OWTS shall be submitted in accordance with application procedures prescribed in the Onsite Systems Manual.

b. Site evaluations, including soil profile inspection, soil percolation testing and groundwater evaluation, shall be conducted in accordance with procedures as prescribed in the Onsite Systems Manual.

c. Engineering plans for alternative OWTS shall be prepared and signed by a qualified OWTS design professional who is knowledgeable and experienced in the field of onsite wastewater treatment and dispersal. The qualified OWTS design professional shall also be responsible for inspection of system installation to assure conformance with approved plans, and shall provide an "as-built" drawing of the installation to Environmental Health and the property owner. The construction inspection by the qualified OWTS design professional shall be in addition to standard County inspection work carried out in accordance with section 4.84.070 of this chapter and the Onsite Systems Manual.

d. Engineering plans will be reviewed by Environmental Health and, where warranted, Environmental Health may refer the plans to the applicable CRWQCB staff and/or external third-party consultant(s) for additional review, the costs for which will be the responsibility of the applicant.

e. Upon completion of installation of alternative OWTS, a release letter shall be submitted by the system designer that the system has been installed and is functioning as designed.

f. Installation permits issued for alternative OWTS are subject to the same expiration and extension time frames as specified in section 4.84.080 of this chapter.

(Ord. No. 04754, § 1, 1-5-2016)

a. In addition to an installation permit, an operating Permit is required for all alternative OWTS, including those installed in connection with the repair or upgrade of existing OWTS as well as those for new construction. General requirements pertaining to operating permits are as follows:

1. The operating Permit will be issued by Environmental Health following: (a) completion of construction of the alternative OWTS; (b) satisfactory compliance with the installation Permit requirements; and (c) payment of applicable fees. Operating permits are non-transferable. Operating permits must also be renewed at the time of change in property ownership.

2. After initial issuance, the operating Permit is required to be renewed periodically with the standard renewal period being one year. Environmental Health may establish conditions allowing the time period between renewals to be extended for certain types of OWTS based on a record of favorable performance or other factors warranting a reduction in system oversight by Environmental Health. Provisions for adjusting the Operating Permit renewal period shall be prescribed in the Onsite Systems Manual.

3. Operating permits are intended to serve as the basis for verifying the adequacy of alternative OWTS performance and ensuring on-going maintenance. Permit conditions shall include monitoring and inspection requirements, Permit duration, and other provisions as prescribed in the Onsite Systems Manual or as deemed appropriate by Environmental Health on a case-by-case basis.

4. Renewal of an operating Permit requires: (a) payment of the applicable fees, upon receipt of notice from Environmental Health; and (b) submission of the results of required system inspection and monitoring.

5. Failure to pay the required fee or submit the specified monitoring and inspection information, or failure to undertake any required corrective work specified by Environmental Health may be cause for issuance of a citation, penalty fees, non-renewal and/or revocation of the Operating Permit by Environmental Health. Environmental Health may place a lien on the property for recovery of any associated abatement costs and unpaid fees.

b. An operating Permit may also be utilized for circumstances other than alternative OWTS, such as for larger flow OWTS (>2,500 gpd), or where, in the opinion of Environmental Health, the type, size, location or other aspects of a particular OWTS installation or portable toilet installation warrant the additional level of oversight provided by an operating permit. In such cases, the issuance and scope of operating permits will be issued in accordance with the general requirements listed in subsections a.1. through a.5. above, and any additional requirements prescribed in the Onsite Systems Manual for particular circumstances.

(Ord. No. 04754, § 1, 1-5-2016)

a. A monitoring program will be established for each alternative OWTS as a condition of the operating Permit at the time of Permit issuance, and may be amended at the time of Permit renewal. Said monitoring shall be performed to ensure that the alternative OWTS is functioning satisfactorily to protect water quality and public health and safety. The monitoring program will be in accordance with guidelines prescribed in the Onsite Systems Manual.

b. Inspection and monitoring results shall be submitted to Environmental Health in accordance with reporting guidelines as prescribed in the Onsite Systems Manual.

c. Environmental Health will compile and review monitoring and inspection results for alternative OWTS and periodically provide a summary of results to the San Francisco Bay and Central Coast Regional Water Quality Control Boards. Based on this review, Environmental Health may require corrective action for specific properties or certain types of alternative OWTS, or general changes in monitoring and inspection requirements.

(Ord. No. 04754, § 1, 1-5-2016)

All requirements specified in section 4.84.120 of this chapter shall also apply to alternative OWTS. However, vertical separation distance between trench bottom and groundwater may be reduced from five (5) feet to three (3) feet by utilizing supplemental treatment OWTS or pressure-dosing distribution dispersal system in compliance with criteria as prescribed in the Onsite Systems Manual. In addition, pressure-dosing distribution dispersal systems shall be required on slopes exceeding thirty-five percent (35%), and for areas with average soil percolation rate between 0.75- and one (1.0-) inches per hour. Design and construction of Alternative OWTS shall be in conformance with requirements as prescribed in the Onsite Systems Manual.

(Ord. No. 04754, § 1, 1-5-2016)