Non-Discharge Effluent Monitoring Policy 160209

State of North Carolina
Department of Environment and Natural Resources
Division of Water Resources
WATER QUALITY PERMITTING SECTION
NON-DISCHARGE EFFLUENT MONITORING FOR DOMESTIC WASTEWATER

February 9, 2016
PCS
Code Parameter – PCS Code Units Frequency 1 Sample Type 2
00310 BOD, 5-Day (20 ºC) mg/L See Table 2 Composite 3
00940 Chloride (as Cl) 4 mg/L Same as GW monitoring Composite 3
50060 Chlorine, Total Residual 5 mg/L Major 6 5 x Week 8 Grab 10
Minor 7 Weekly 9
31616 Coliform, Fecal MF, M-FC Broth, 44.5 ºC #/100 mL See Table 2 Grab 10
50050 Flow, in Conduit or thru Treatment Plant 11 GPD Major 6 Continuous Major 6 Recorder
Minor 7 Monthly Minor 7 Estimate
00610 Nitrogen, Ammonia Total (as N) mg/L See Table 2 Composite 3
00620 Nitrogen, Nitrate Total (as N) mg/L See Table 2 Composite 3
00625 Nitrogen, Kjeldahl, Total (as N) mg/L See Table 2 Composite 3
00600 Nitrogen, Total (as N) mg/L See Table 2 Composite 3
00400 pH s.u. Major 6 5 x Week 8 Grab 10
Minor 7 Weekly 9
00665 Phosphorus, Total (as P) mg/L See Table 2 Composite 3
70300 Solids, Total Dissolved – 180 ºC 4 mg/L Same as GW monitoring Composite 3
00530 Solids, Total Suspended mg/L See Table 2 Composite 3
00076 Turbidity, HCH Turbidimeter 12 NTU Continuous Recorder
1. Permits not matching recommended sampling frequencies shall include documentation in the Cover Letter and
Attachment A footnotes supporting this variation.
2. For Active Treatment Systems (e.g., extended aeration, anoxic, MBR, etc.), if Q < 30,000 GPD, sample type can be
grab (15A NCAC 02B .0505). For Passive Treatment Systems (e.g., facultative lagoons, septic tanks, etc.), sample type
shall be grab.
3. See 15A NCAC 02B .0503(4).
4. Applicable only for facilities with groundwater monitoring wells.
5. Applicable only if chlorine is used as a disinfectant.
6. Q ≥ 10,000 GPD.
7. Q < 10,000 GPD.
8. Lagoon type systems with weekly ORC visits can have a weekly sampling frequency for pH and/or Total Residual
Chlorine.
9. Total Residual Chlorine / pH can be “Per Event” if Permittee documents that the facility infiltrates/irrigates at a rate
less than once per week.
10. See 15A NCAC 02B .0503(14).
11. Flow thru treatment plant should be monitored at a representative location (i.e., flow monitoring is not acceptable
following treatment systems with substantial equalization such as lagoons).
12. Applicable only for Reclaimed Water facilities, and facilities complying with the High-Rate Infiltration Policy.
Table 2 – Recommended Sampling Frequencies
Flow
(GPD)
Active Treatment Systems (e.g., extended aeration, anoxic, MBR, etc.) Passive Treatment Systems
(e.g., facultative lagoons,
septic tanks, etc.)
Mainland Systems
Year-round
Coastal Barrier Island Systems
September 1st to April 30th
Coastal Barrier Island Systems
May 1st to August 31st
With BNR 1 Without BNR With BNR 1 Without BNR With BNR 1 Without BNR
≤ 1000 3 x Year 3 x Year 3 x Year 3 x Year 3 x Year 3 x Year Annual
> 1,000 to 10,000 Monthly 4 x Year Monthly 4 x Year Weekly Monthly 3 x Year
> 10,000 to 100,000 2 x Month Monthly 2 x Month Monthly Weekly Weekly 4 x Year
> 100,000 to 500,000 2 x Week 2 x Month 2 x Week 2 x Month 2 x Week Weekly Monthly
> 500,000 3 x Week 2 x Week 3 x Week 2 x Week 3 x Week 2 x Week 2 x Month
1. Applies when Total Nitrogen (TN) and/or Total Phosphorus (TP) limits are met by a Biological Nutrient Removal (BNR) process.
Table 3: Minimum Operator of Responsible Charge (ORC) Visitation Requirements for Classified Facilities (15A NCAC 08G .0204)
Treatment Type Flow Criteria Classification Minimum ORC Visitation
Schedule
Surface Irrigation Systems with the exception of (a) and (b) N/A Surface Irrigation System Weekly 1
Domestic systems with septic tank/sand filters; biological lagoons;
or constructed wetlands ≤ 1,500 GPD Surface Irrigation System 2 x Year 2
Domestic systems with ATUs (aerobic treatment units) ≤ 1,500 GPD Surface Irrigation System 2 x Year 2
Activated sludge or fixed growth 1,500 GPD to 0.5 MGD Grade II Biological 5 x Week
Activated sludge or fixed growth + BNR required by permit 3 1,500 GPD to 0.5 MGD Grade III Biological 5 x Week
Activated sludge or fixed growth 0.5 to 2.5 MGD Grade III Biological 5 x Week
Activated sludge or fixed growth + BNR required by permit 3 0.5 to 2.5 MGD Grade IV Biological 5 x Week
Activated sludge or fixed growth > 2.5 MGD Grade IV Biological 5 x Week
Physical process (DAF, screening, filtration) N/A Grade I Phys/Chem Weekly
Chemical process, RO, electrodialysis, and ultrafiltration N/A Grade II Phys/Chem 5 x Week
1. In the event of dual classification as a Surface Irrigation System and a Biological Treatment System, the visitation schedule for the surface irrigation system
applies only to the irrigation portion of the system. The biological wastewater treatment facility visitation is set by a separate classification.
2. There must be a six month interval between visits.
3. Applies when Total Nitrogen (TN) and/or Total Phosphorus (TP) limits are met by a Biological Nutrient Removal (BNR) process.