Administrative Code

Creating a Report: Check the sections you'd like to appear in the report, then use the "Create Report" button at the bottom of the page to generate your report. Once the report is generated you'll then have the option to download it as a pdf, print or email the report.

Virginia Administrative Code
Title 9. Environment
Agency 25. State Water Control Board
Chapter 790. Sewage Collection and Treatment Regulations
8/11/2020

9VAC25-790-960. Influent and Effluent Sampling.

A. Sampling tests and frequency. Table C lists the typical recommended minimum sampling program schedules for all sewage treatment works (STW).

B. STW effluent tests and frequency of effluent testing and frequency of other sampling for a treatment works will be provided in the VPDES permit or the VPA permit.

TABLE C. TYPICAL SAMPLING PROGRAMS FOR SEWAGE TREATMENT WORKS.

PLANT SIZE

>2.01 MGD

1.0-2.0 MGD

0.101-0.999 MGD

0.401-0.1 MGD

0.0011-0.04 MGD

Flow

Totalizing, Indicating & Recording

Totalizing, Indicating & Recording

Totalizing, Indicating & Recording

Totalizing, Indicating & Recording

Estimate

BOD5, TSS, TKN

24- HC
1/ Day

24- HC
5 Days/ Wk

8-HC
3 Days/ Wk

4-HC
1 Day/ Wk

Grab
1/month

Total Nitrogen* Total Phosphorus*

24- HC
1/ Week

24- HC
1/ Week

8-HC
1/ 2 Weeks

4-HC
1/ Month

Grab
1/month

TRC, Contact tank**

Grab 1/2 Hr

4/Day at 4 Hr.Intervals

3/Day at 4 Hr.Intervals

3/Day at 4 Hr.Intervals

Grab
1/Day

Fecal Coliform**

Grab
1/Day
10am-4pm

Grab
5 Days/Wk
10am-4pm

Grab
3 Days/Wk
10am-4pm

Grab
1/Week
10am-4pm

Grab
1/Month
10am-4pm

pH, DO, TRC Effluent

Grab
1/Day

Grab
1/Day

Grab
1/Day

Grab
1/Day

Grab
1/Day

WQS Parameters (Toxics)

1/8,24 HC or 1/month

1/8,24 HC or 1/month

1/8, 8HC or 1/month

1/8, 4HC or 1/month

Grab
1/month

Statutory Authority

§ 62.1-44.19 of the Code of Virginia.

Historical Notes

Former 12VAC5-581-1020 derived from Volume 18, Issue 10, eff. February 27, 2002; amended and adopted as 9VAC25-790-960, Virginia Register Volume 20, Issue 09, eff. February 12, 2004.

Website addresses provided in the Virginia Administrative Code to documents incorporated by reference are for the reader's convenience only, may not necessarily be active or current, and should not be relied upon. To ensure the information incorporated by reference is accurate, the reader is encouraged to use the source document described in the regulation.

As a service to the public, the Virginia Administrative Code is provided online by the Virginia General Assembly. We are unable to answer legal questions or respond to requests for legal advice, including application of law to specific fact. To understand and protect your legal rights, you should consult an attorney.