(1) The design engineer shall identify sewage characteristics in terms of the following:
(a) CBOD5, TSS, O&G, BOD5, and fecal coliform bacteria;
(b) Other parameters that can impact treatment anywhere in the treatment sequence including, but not limited to, pH, temperature and dissolved oxygen; and
(c) Nitrogen and phosphorus, where either parameter is identified as a contaminant of concern.
(2) For LOSS treating sewage from nonresidential or commercial sources, the design engineer shall submit:
(a) Discharger information to show the sewage is not from an industrial facility;
(b) Sewage characterization that identifies any parameters not typically found in residential strength sewage; and
(c) Data that demonstrates that effluent quality is or will be equivalent to or better than effluent from a properly sized septic tank treating residential strength sewage.
[Statutory Authority: RCW
70.118B.020. WSR 11-12-035, § 246-272B-06200, filed 5/25/11, effective 7/1/11.]