Presentation Abstract

Sewage typically contains high levels of nitrogen. Even with new technologies, on-site sewage (septic) treatment systems typically do not reduce nitrogen levels in treated wastewater. Cost effective on-site sewage systems with adequate denitrification capabilities are needed for areas where nitrogen has been determined a contaminant of concern. A collaborative effort between the Washington State Department of Health and the University of Washington Civil and Environmental Engineering Department was undertaken to design and evaluate cost effective, reliable, and low maintenance public domain treatment technologies that have high nitrogen removal efficiencies. The systems were installed and tested at the Snoqualmie Wastewater Treatment Plant. In addition to meeting low effluent biochemical oxygen demand and low total and volatile suspended solids concentrations and bacteriological reduction, a major treatment objective was to produce an effluent TN concentration below 20 milligrams per liter (mg/L). A total nitrogen (TN) concentration of less than 20 mg/L is the Washington State technology-based standard for on-site nitrogen removal. Using the EPA Environmental Technology Verification protocol for nutrient reduction, three novel systems were evaluated for performance and denitrification capability. All three systems met the objective of reducing total nitrogen concentrations to less than 20 mg/L. This presentation will summarize the system designs, evaluation protocols, results, and next steps.

Session Title

Session S-06C: Water Quality III

Conference Track

Water Quality

Conference Name

Salish Sea Ecosystem Conference (2014 : Seattle, Wash.)

Document Type

Event

Start Date

1-5-2014 1:30 PM

End Date

1-5-2014 3:00 PM

Location

Room 606

Genre/Form

conference proceedings; presentations (communicative events)

Contributing Repository

Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.

Subjects – Topical (LCSH)

Sewage--Purification--Nitrogen removal--Washington (State)--Puget Sound; Sewage disposal--Technological innovations--Washington (State)--Puget Sound

Geographic Coverage

Salish Sea (B.C. and Wash.); Puget Sound (Wash.)

Rights

This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.

Type

Text

Language

English

Format

application/pdf

COinS
 
May 1st, 1:30 PM May 1st, 3:00 PM

Three Cost-effective Public Domain On-site Sewage Treatment Technologies Verified for Their Ability to Denitrify

Room 606

Sewage typically contains high levels of nitrogen. Even with new technologies, on-site sewage (septic) treatment systems typically do not reduce nitrogen levels in treated wastewater. Cost effective on-site sewage systems with adequate denitrification capabilities are needed for areas where nitrogen has been determined a contaminant of concern. A collaborative effort between the Washington State Department of Health and the University of Washington Civil and Environmental Engineering Department was undertaken to design and evaluate cost effective, reliable, and low maintenance public domain treatment technologies that have high nitrogen removal efficiencies. The systems were installed and tested at the Snoqualmie Wastewater Treatment Plant. In addition to meeting low effluent biochemical oxygen demand and low total and volatile suspended solids concentrations and bacteriological reduction, a major treatment objective was to produce an effluent TN concentration below 20 milligrams per liter (mg/L). A total nitrogen (TN) concentration of less than 20 mg/L is the Washington State technology-based standard for on-site nitrogen removal. Using the EPA Environmental Technology Verification protocol for nutrient reduction, three novel systems were evaluated for performance and denitrification capability. All three systems met the objective of reducing total nitrogen concentrations to less than 20 mg/L. This presentation will summarize the system designs, evaluation protocols, results, and next steps.