Laserfiche WebLink
48 <br /> <br />SECTION 5 - SAMPLING AND ANALYTICAL REQUIREMENTS <br /> <br />5.1 Sampling Requirements for Users. <br /> <br />All samples shall be taken in a manner so they are representative of the wastestream <br />being sampled. <br /> <br /> A. Where the discharge is continuous, a minimum of four (4) grab samples shall be <br />taken for cyanide, total phenols, oil and grease, sulfide, and volatile organics. For <br />all other pollutants, 24-hour composite samples shall be obtained through flow- <br />proportional composite sampling techniques where feasible. The City may waive <br />flow-proportional composite sampling for any user that demonstrates that flow- <br />proportional is not feasible. In such cases, samples may be obtained through <br />time-proportional composite sampling techniques or through a minimum of four <br />(4) grab samples where the user demonstrates that this will provide a <br />representative sample of the effluent being discharged. Multiple grab samples <br />for cyanide, total phenols, and sulfides may be composited in the field, volatile <br />organics and oil and grease should be composited in the laboratory. Composite <br />samples for other parameters unaffected by the compositing procedures as <br />documented in approved EPA methodologies may be authorized by the Director, <br />as appropriate. In addition, grab samples may be required to show compliance <br />with instantaneous limits. <br /> <br /> B. Samples shall be taken immediately downstream from pretreatment facilities if <br />such exist or immediately downstream from the regulated or manufacturing <br />process if no pretreatment exists or as determined by the City and/or contained <br />in the user's wastewater discharge permit. For categorical users, if other <br />wastewaters are mixed with the regulated wastewater prior to pretreatment the <br />user shall measure the flows and concentrations necessary to allow use of the <br />combined wastestream formula of 40 CFR 403.6(e) in order to evaluate <br />compliance with the Applicable Categorical Pretreatment Standards. For other <br />SIUs, for which the City has adjusted its local limits to factor out dilution flows, <br />the user shall measure the flows and concentrations necessary to evaluate <br />compliance with the adjusted pretreatment standard(s). <br /> <br /> C. In the case of batch discharges, the samples shall be obtained in a manner that <br />ensures they are representative of the batch. <br /> <br /> D. All sample results shall indicate the time, date and place of sampling, and <br />methods of analysis, and shall certify that such sampling and analysis is <br />representative of normal work cycles and expected pollutant discharges from <br />the user. If a user sampled and analyzed more frequently than what was