Spokane Municipal Code

Title 13 Public Utilities and Services

Chapter 13.03A Pretreatment

Article V. Sampling and Analytical Requirements

Section 13.03A.0501 Sampling Requirements for Users [5.1]

1. Samples.

1. 1. Grab samples must be used for pH, cyanide, total phenols, oil and grease, sulfide and volatile organic compounds. For all other pollutants, twenty-four hour composite samples must be obtained through time-proportional composite sampling techniques, unless flow-proportional composite sampling or grab sampling is required by the Plant Manager. The samples must be representative of the discharge and the decision to allow the alternative sampling must be documented in the industrial user file for the facility or facilities.

1. 2. Using protocols (including appropriate preservation) specified in 40 CFR Part 136 and applicable EPA guidance, multiple grab samples collected during a twenty-four hour period may be composited prior to the analysis as follows: for cyanide, total phenols, and sulfides the samples may be composited in the laboratory or in the field. For volatile organics and oil and grease, the samples may be composited in the laboratory.

1. 3. Composite samples for other parameters unaffected by the compositing procedures as documented in approved EPA methodologies may be authorized by the Plant Manager, as appropriate. In addition, grab samples may be required to show compliance with instantaneous limits. Samples for oil and grease, temperature, pH, cyanide, total phenols, sulfides, and volatile organic compounds must be obtained using grab collection techniques.

2. For sampling required in support of baseline monitoring and ninety day compliance reports, a minimum of four grab samples must be used for pH, cyanide, total phenols, oil and grease, sulfide and volatile organic compounds for facilities or processes for which historical sampling data do not exist. For facilities for which historical sampling data are available, the Plant Manager may authorize a lower minimum. For the reports required by 40 CFR 403.12(e) and (h), the industrial user is required to collect the number of grab samples necessary to assess and assure compliance with applicable pretreatment standards and requirements. (Cross reference: Ninety-day report, see SMC 13.03A.0402 and 40 CFR 403.12(b) and (d))

3. Samples shall be taken immediately downstream from pretreatment facilities if such exist, or immediately downstream from the regulated or manufacturing process if no pretreatment facilities exist. The location shall be specified in the discharge permit. For categorical users, when wastewater subject to a categorical pretreatment standard is mixed with other wastewater, the user shall measure the flows and concentrations necessary to allow use of a combined wastestream formula (CWF) in accordance with 40 CFR 403.6(e) to evaluate compliance with applicable categorical standards. For other SIUs, wastewater for which the City has adjusted its local limits to factor out dilution flows, the user shall measure the flows and concentrations necessary to evaluate compliance with the adjusted pretreatment standards.

4. All sample results shall indicate the time, date and place of sampling, and methods of analysis and shall certify that the wastestream sampled is representative of normal work cycles and expected pollutant discharges from the user. If a user sampled and analyzed more frequently than what was required in its wastewater discharge permit, using methodologies in 40 CFR Part 136, it must submit all results of sampling and analysis of the discharge as part of its self-monitoring report.

NOTE: Bracketed enumerations reference the numbering in the EPA Region 10 Model Ordinance of March 27, 2012.

Date Passed: Monday, November 9, 2020

Effective Date: Wednesday, December 16, 2020

ORD C35961 Section 49