NCS000251_SWPPP 4_20221207

N �� permit No t4csow2s 1
AIVALVTICAL MONITORING REQUIREMENT,
caimonitor~
monitori ofstormwater discharges shall be performed as
z ni[oring will res $ shall be performed during a representative storm evetniedThe required
in sb All
the permit at c it in a minimum often analytical samplings bein
-� storm water discharge outfall (SDO). g c°Mlucted over the term of
A representative
this save atoms event is a storm event that measures greater than 0.1 inches of rainfall. The time
72 hours. A sing event and tite previous storm event measuring
it rains but stops bef °nn event may have a period of no precipitation greater
up to �0 hours. For examplemust be at , roducin a disch reproducing any collectable discharge, a sam l
ar c be ins within 10 hours. ' p e ma y be O°Ilected if the next rain
Table 1.
Anal
vtical Monitorin Re uirements
Discharge
Characteristics Measurement Frequency) Sample Sample
Non -Polar Oil & Grease / TPH Units T e2 Location3
EPA Method 1664 SGT-HEM mg/11, semi-annual Grab SDO
Biochemical Ox �
Y en Demand m semi-annual
Chemical Oxygen D Grab SDO
Nitrogen. errand m �- semi-annual Grab SDO
g ,Total semi-annual
Phosphorous mg� Grab SDO
Total mg/L semi-annual
Cresol, Total Grab SDO
Phenol4 mg/L semi-annual Grab SWDBO
mg/L semi-annual Grab SWDBO
Formaldehyde4 semi-annual
mg/L Grab SWDBO
PH
Total Rainfalls standard semi-annual
Grab SDO
inches semi-annual Rain _
Gauge
Footnotes:
1 Measurement Frequency: Twice per year during a representative storm event.
2 Grab samples shall be collected within the first 30 minutes of discharge.
3 Sample Location: Samples shall be collected at all the stormwater discharge outfalls (SDO) including the stormwater
detention basin outfall (S WDBO).
4 Monitor in stormwater detention basin (SWDB) prior to each storm event that could prompt discharge. The Chemetrics
test and gas chromatograph analysis is recommended for detection of phenol and formaldehyde. Spray irrigation is
required iftest results exceed 2. 0 mg/L for phenol or ].0 mg/L for formaldehyde. Spray irrigation treatment shall continue
until samples show concentrations in the SWDB are below these thresholds.
5 For each sampled representative storm event the total precipitation must be recorded. An on -site rain gauge or local rain
gauge reading must be recorded.
The permittee shall complete the minimum ten analytical samplings in accordance with the
schedule specified below in Table 2. A minimum of 60 days must separate Period 1 and
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