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Large On-Site Sewage System Program

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Large On-site Sewage Systems (LOSS) Program

The LOSS Program reviews and approves Large On-site Sewage System (LOSS) project applications state-wide (except as noted below under "Regulatory Jurisdictions").

NOTE: Our Spokane office has moved!

Regulatory Jurisdictions for On-Site Wastewater Projects changed - effective July 1, 2009.

LOSS Program Description

LOSS Designer/Installer Qualifications

Fees for LOSS Project Review

LOSS Program Staff

LOSS Rule Development Activities

Regulatory Jurisdictions
for On-Site Wastewater
(See below for exceptions and more detail):

The Local Health Officer has authority and approval over:

(a) Systems with design flows through any common point up to 3,500 gallons per day.

(b) Any Large On-site Sewage System for which jurisdiction has been transferred by the department to a local health jurisdiction by contract. Counties with such agreements currently include Clallam, King, Kitsap, Thurston and San Juan.

As of July 1, 2009, the Washington State Department of Health (Large On-Site Program) per Chapter 70.118B RCW, has authority and approval over:

(a) Sewage systems with domestic strength design flows through any common point between 3,500 to 100,000 gallons per day that use subsurface treatment or disposal.  May include mechanical treatment.

(b) Any Large On-site Sewage System for which jurisdiction has been transferred to the Department of Health from Department of Ecology in accordance with the statute.

The Washington State Department of Ecology has authority and approval over:

(a) Domestic or industrial wastewater under chapter 173-240 WAC.

(b) Sewage systems with subsurface disposal with design flows above 100,000 gallons per day.

(c) Sewage systems with subsurface disposal that treat industrial waste.

(d) Any system utilizing subsurface disposal that receives a federal or state construction grant administered by Ecology. Ecology will co-review and approve the planning and construction documents with Department of Health.  Department of Health will issue the permit and regulate the system.

(e) Sewage systems with subsurface disposal where the effluent is in hydraulic continuity with surface water.

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The DOH LOSS Program:

• Reviews and approves LOSS project applications.

• Performs "pre-site" (soils) inspections and "final" (post construction) inspections for LOSS projects.

• Issues and tracks operating permits for all active LOSS projects.

• Conducts enforcement actions for LOSS failures.

• Provides LOSS project-related technical assistance.

• Reviews and approves septic tank applications.

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LOSS Designer and Installer Qualifications:

Per WAC 246-272B, all LOSS project design documents submitted to the Washington state Department of Health for review and approval must be prepared and stamped by a licensed professional engineer.

Only qualified (approved by local health jurisdiction) on-site sewage system installers may construct LOSS projects.

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Fees for LOSS Project Review

Fees for large onsite sewage system project review, inspections and operating permits were adopted September 26, 2006 and became effective on January 1, 2007, for projects submitted after that date. The base fee is required at the time of application. Any hourly fees for additional review time must be paid in full before final approval is granted. The fees are as follows:

1. Plan review and inspection. The following fees apply for LOSS application, review and inspection:

2. Operating permits The following fees apply for annual LOSS operating permits and renewals.

[Statutory Authorities:  RCW 43.20.050, 43.70.110; 43.70.250, and Chapter 246-272B-990 WAC]

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Our Spokane office has moved:

Friday, June 5, 2009 our Spokane Office staff moved to their permanent location in Spokane Valley.
The mailing and physical address is:

16201 E. Indiana Avenue, Suite 1500
Spokane Valley, WA  99019

They received NEW PHONE NUMBERS at that time.

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Last Update: 09/22/2009 06:45 AM