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Currently the State of Washington requires that all private and public septic systems need periodic inspections by a licensed Septic O & M inspector.

What is Operation and Maintenance (O&M)?

Operation and maintenance (O&M) is about On-Site Sewage Systems (OSS) functioning properly and being cared for correctly. In order for an OSS to continue to function properly, care must be taken by those responsible for it. Think of an OSS as a personal wastewater treatment plant. Proper monitoring, correct operation and maintenance are the responsibility of the OSS owner.

Evaluation of Your OSS

Upon completion of training, homeowners may perform their own OSS evaluations for six consecutive years. Following each six year period, the next required OSS evaluation must be completed by a licensed O&M Specialist.

A Report of System Status (ROSS) is completed at the time of the evaluation and submitted to the Whatcom County Health Department (WCHD) with a $35 filing fee. For each evaluation of your OSS, a ROSS must be submitted.

When do I need an OSS Evaluation?

• Once every three years for conventional gravity systems (systems consisting of a septic tank and drain field ONLY).

• Annually for all other systems unless more frequently as specified by the manufacturer.

• When a property is offered for sale and there is no current ROSS on file by an O&M Specialist.

Who are the O&M Specialists?

Professionals licensed individually by WCHD who:

Passed an examination

Posted a bond with WCHD

Maintain verifiable ongoing education or continuing education units (CEU).

Why do I need to perform Operations and Maintenance on my system?

1. Protect your investment in your property.

Look at it from this perspective: You can spend a few dollars, or some of your time every year to maintain your septic system or you can spend $20,000 or more to replace it. In the long run it makes more sense to spend a little effort every year and save a significant amount of money in the long run. Your septic system will not last forever. The EPA and Washington Department of Health estimate that the average life expectancy of a septic system is only 20 to 30 years. However, poorly maintained and operated systems can fail in only a year or two. While well maintained systems can surpass the 30 year mark. It is similar to owning a car. You spend a large amount of money to purchase it even though you know that its life expectancy is less than twenty years. You also know that if you perform regular service on the

vehicle it will run better and last longer.

2. Protect your health and your neighbors.

Under-treated sewage contains organisms that can cause life-threatening diseases. If your septic system is poorly maintained these organisms can enter

the environment and threaten the health & welfare of children, household pets, and even wild animals.

3. Pumping your septic tank when it is needed can save you money.

Many people think that the septic tank is the most expensive part of their system. As it turns out replacing a septic tank is relatively inexpensive compared to replacing the rest of the system. It is important to check your septic tank because

you can extend the life of your system. When septic tanks are not pumped as needed, sludge from the tank begins to enter the drainfield and clog the soil pores. When the soil pores become plugged the drainfield stops functioning correctly

and the system fails. Pumping the tank when it is needed will keep sludge out of your drainfield and extend the life of your system.

4. Under-treated sewage leads to environmental issues.

Washington State University and the State Department of Ecology, authored a study on Silver Lake. The study concluded that under-treated and untreated septic sewage was partially to blame for the algae and plant blooms that are causing problems at the lake.

5. It is the Law.

This is everybody's least favorite answer but it is still the fact. State and county rules require homeowners to perform regular O&M on their system. Washington Administrative Code 246-272A-0270 and Chapter 24.05 Whatcom County Code explain the requirement.

Whatcom County Revised Code

24.05.160 Operation and maintenance.

A. The OSS owner is responsible for properly operating, monitoring and maintaining the OSS to minimize the risk of failure, and to accomplish this purpose, shall:

1. Obtain approval from the health officer before repairing, altering or expanding an OSS

2. Secure and renew contracts for periodic maintenance where required by the WCHD

3. Obtain and renew operation permits if required by the WCHD

4. Assure a complete initial evaluation of the system components and/or property by a licensed O&M Specialist to determine functionality, maintenance needs and compliance with this chapter and any permits. A Report of System Status shall be completed at thetime of evaluations and submitted to the WCHD.

5. Assure subsequent evaluations of the system components and/or property are

completed as follows:

i. At least once every three years for all systems consisting solely of a septic

tank and gravity SSAS

ii. Annually for all other systems unless more frequent inspections are specified by the health officer

6. Employ an approved pumper to remove the septage from the tank when the level of solids and scum indicates that removal is necessary

7. Provide maintenance and needed repairs to promptly return the system to a properoperating condition

8. Protect the OSS area and the reserve area from:

i. Cover by structures or impervious material

ii. Surface drainage and direct drains, such as footing or roof drains. The drainage must be directed away from the area where the OSS is located

iii. Soil compaction, for example by vehicular traffic or livestock and

iv. Damage by soil removal and grade alteration.

9. Keep the flow of sewage to the OSS at or below the approved operating capacity and sewage quality

10. Operate and maintain systems as directed by the health officer

11. Request assistance from the health officer upon occurrence of a system failure or suspected system failure

12. At the time of property transfer, provide to the buyer, a copy of the current report of system status on file with the Whatcom County Health Department, and any available maintenance records, in addition to the completed seller disclosure statement inaccordance with Chapter 64.06 RCW for residential real property transfers.

13. Ensure that a current Report of System Status by a licensed O&M specialist is on file with WCHD when a residence is offered for sale.

B. OSS owners may perform their own OSS evaluation in accordance with WCC 24.05.160.C. except for the following:

1. OSS technologies that are listed as proprietary on the WA State DOH list of registered onsite treatment and distribution products

2. Community drainfields

3. Nonconforming replacement systems that do not meet vertical and horizontal separation installed as a result of a system failure

4. OSS serving Food Service Establishments.

C. OSS owners who choose to perform their own evaluations shall complete O&M homeowner training as approved by the health officer. Upon completion of training, OSS owners may perform their own evaluation for six consecutive years. Following each six year period, the next required evaluation must be completed by a licensed O&M specialist. If OSS owners are discovered to be repeatedly noncompliant with 24.05.160, all subsequent evaluations shall be performed by a licensed O&M specialist.

D. Persons shall not:

1. Use or introduce strong bases, acids or chlorinated organic solvents into an OSS for the purpose of system cleaning

2. Use a sewage system additive unless it is specifically approved by WDOH or

3. Use an OSS to dispose of waste components atypical of residential wastewater.

E. The health officer shall require annual inspections of OSS serving food service

establishments and may require pumping as needed.

Effluent backflowing from drainfield pipes

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