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City of San Mateo Municipal Code.


(a) As a condition of discharge, the Director may require that the user conduct a sampling and analysis program of the user's wastewater discharge of a frequency and type required by the Director to demonstrate compliance with the requirements of this chapter. The waste discharge permit shall specify the minimum frequency and types of samples, flow monitoring, measuring, and analyses to be conducted by the user. The permit may also specify the type of sampling equipment and flow monitoring equipment, which must be installed or used. The required self-monitoring program will depend on factors such as flow, potential for the discharge to cause interference, pass-through, or upset of treatment processes, pollutants present, and prior compliance his-tory, if any, of the user. Additional monitoring may be required by the Director for violation follow up, to assist in evaluating effects of the discharge, or as part of a compliance directive or notice of violation.

(b) Information to be included in self-monitoring reports, and acceptable sampling and analytical methods are specified in the pretreatment regulations and this chapter. Samples shall be analyzed at the user's expense, by a laboratory accredited by the State of California Department of Health Services for such analysis. The detection limit used by the user shall be no greater that the applicable regulatory limit of the parameter as specified in the waste discharge permit.

(c) If sampling performed by the user indicates a violation, the user shall notify the Director as soon as possible but no later than within 24 hours of the user's knowledge of the violation. The user shall repeat the sampling and analysis and report the results to the Director within 30 days after becoming aware of the violation. Where the Director has performed the sampling and analysis in lieu of the user, the Director must perform the repeat sampling and analysis unless it notifies the user of the violation and requires the user to perform the repeat analysis. The user is not required to resample if the Director samples between the user's initial sampling and the user's receipt of the sampling results.

(d) The self-monitoring reports and notices required by the pretreatment regulations shall be submitted to the Director on the date specified.

(e) The Director may require self-monitoring for facilities for which a permit has not been issued. The Director may also request that information be submitted within a reasonable time concerning the chemical or biological constituents of any substance or chemical product that could potentially be discharged to the sanitary sewer system or which the Director determines may, alone or in accumulation with other discharges, contribute to a violation by the POTW of its NPDES permit or contribute to an upset of plant processes.

(f) If a user subject to the reporting requirements monitors any regulated pollutant at the appropriate sampling location more frequently than required by the Director, using the procedures prescribed in this section, the results of this monitoring shall be included in the report.

(g) The Director may authorize an industrial user subject to a categorical pretreatment standard to forego sampling of a pollutant regulated by a categorical pretreatment standard if the industrial user has demonstrated through sampling and other technical factors that the pollutant is neither present nor expected to be present in the discharge, or is present only at background levels from intake water and without any increase in the pollutant due to activities of the industrial user in accordance with 40 CFR 403.12(e)(2). This authorization is subject to the following conditions:

(1) The waiver may be authorized where a pollutant is determined to be present solely due to sanitary wastewater discharged from the facility provided that the sanitary wastewater is not regulated by an applicable categorical standard and otherwise includes no process wastewater.

(2) The monitoring waiver is valid only for the duration of the effective period of the individual wastewater discharge permit, but in no case longer than five years. The user must submit a new request for the waiver before the waiver can be granted for each subsequent individual wastewater discharge permit.

(3) In making a demonstration that a pollutant is not present, the industrial user must provide data from at least one sampling of the facility's process wastewater prior to any treatment present at the facility that is representative of all wastewater from all processes.

(4) The request for a monitoring waiver must be signed by an authorized representative of the user in accordance with Section 7.38.030, and include the certification statement in Section 7.38.230 and 40 CFR 403.6(a)(2)(ii).

(5) Non-detectable sample results may be used only as a demonstration that a pollutant is not present if the EPA approved method from 40 CFR Part 136 with the lowest minimum detection level for that pollutant was used in the analysis.

(6) Any grant of the monitoring waiver by the Director must be included as a condition in the user's permit. The reasons supporting the waiver and any information submitted by the user in its request for the waiver must be maintained by the Director for three years after expiration of the waiver.

(7) Upon approval of the monitoring waiver and revision of the user's permit by the Director, the industrial user must certify on each report with the following statement that there has been no increase in the pollutant in its wastestream due to activities of the user:

Certification of Pollutants not Present

Based on my inquiry of the person or persons directly responsible for managing compliance with the Pretreatment Standard for 40 CFR _______ [specify applicable National Pretreatment Standard part(s)], I certify that, to the best of my knowledge and belief, there has been no increase in the level of ______ [list pollutant(s)] in the wastewaters due to the activities at the facility since filing of the last periodic report.

(8) In the event that a waived pollutant is found to be present or is expected to be present because of changes that occur in the user's operations, the user must immediately: Comply with the monitoring requirements of subsections (a) through (f) of this section, or other more frequent monitoring requirements imposed by the Director, and notify the Director.

(9) This provision does not supersede certification processes and requirements established in categorical pretreatment standards, except as otherwise specified in the categorical pretreatment standard.