Publication Summary

An announced Class II inspection was conducted December 2-4, 1996 at the Blaine Wastewater Treatment Plant, located in Whatcom County. Influent characteristics were generally similar to other typical treatment plants with weak influent.

An announced Class II inspection was conducted December 2-4, 1996 at the Blaine Wastewater Treatment Plant, located in Whatcom County. Influent characteristics were generally similar to other typical treatment plants with weak influent.

Moderately effective reductions in BOD5, TOC, TSS, and ammonia nitrogen occurred across the Blaine treatment plant. Effluent ammonia nitrogen concentration was expected to be reduced to below water quality criteria at the edge of the acute and chronic mixing zone, but it was determined that a reasonable potential exists for the effluent result to exceed the allowable chronic whole effluent ammonia nitrogen concentration. Blaine should conduct additional sampling to determine if this potential persists as sample size increases. Blaine might also establish mitigating dilution factors by conducting a dilution zone study of their discharge.

The 24-hour composite BOD5 and TSS concentrations were within the NPDES weekly and monthly permit limits, but the percent reduction in BOD5 was less than the minimum required by the permit. Effluent fecal coliform results were exceptionally high and exceeded both monthly and weekly average permit limits. All other inspection results were within applicable effluent limits and influent loading limits. Detected whole effluent priority pollutant organics and metals concentrations were generally within marine water quality criteria, with the exception of copper, which exceeded the acute criterion. Blaine should ensure that all concentrations remain within applicable criteria or limits. Split sample comparisons found Ecology and Blaine TSS sample results to be generally similar, but the BOD5 results to be substantially different for both sample and laboratory comparisons. Blaine should review sampling and analytic procedures for BOD5. Fecal coliform concentrations in Blaine sludge exceeds the pathogen limits of Class A land application requirements and it is recommended that these concentrations be reduced for this level of use. Organic and metal concentrations were well within both EPA land application concentration limits and state dangerous waste regulation designation criteria. Discharges from industrial contributors are not expected to have an appreciable effect on plant performance or effluent quality.