NC0044440_Dissoved to Total Metal Calculator_20170717

Date: 5/9/2017
Dissolved to Total Metal Calculator FACILITY: City of Cherryville
NPDES PERMIT: NCO044440 Dissolved to Total Metal Calculator
Do NOT enter any data directly into this spreadsheet.
Enter data onto "Table 1" under the Input Sheet and enter In accordance with Federal Regulations, permit limitations must be written as Total Metals per 40 CFR 122.45(c)
"Effluent Hardness" under the Data Sheet.
In accordance with 40 CFR 122.45 (c ), permits are, have and
Receiving
Receiving
Rec. Stream NPDES Total Suspended
Combined
Combined
nstream
must be written as total metals.
Stream
summer
Stream
summer 7010
1010 Flaw Limit Solids
-Fixed Value-
Hardness
chronic
Hardness
Acute
Wastewater
Concentration
This calculator has been inserted into the RPA to calculate
7010 (CFS)
(MGD)
MGD MGD (mg/L)
(mg/L)
(mg/L)
Chronic)
6.1000
3.9355
3.2774 2.0000 10
26.572
26.769
33.6957
Total Metal allowable allocations once Table 1 has been
completed (Input Sheet) and Effluent hardness has been
entered (Data Sheet).
1) Following the spreadsheet from left to right. First
US EPA Maximum Allowable Effluent Concentration
COMMENTS (identify pammeters to PERC
the allowable allocations for the dissolved metals will
appear for all the metals listed once Table 1 is complete
Dissolved Metals Translators -using (MAEC) as a Total Metal
PARAMETER Default Partition =Dissolved Meld Translator
Chronic Acute Coefficients Chronic Acute
and effluent hardness entered. Use a default value of 25
rug/11f fuq/11 streams rug/11f fug/11
Cadmium d 0.16 0.87 0.252 0.62 3.44
mg/L if no hardness data is available.
Cd -Trout streams 0.16 0.54 0.252 0.62 2.14
Second, the Dissolved Metal allocations are divided by the
Chromium III (d)(h) 25 194 0.202 123.76 957.19
Translators to determine the Total Metals that can be
Chromium VI d 11 16 1.000 11.00 16.00
allocated to the Permittee. These Total Metals values are
Chromium, Total t N/A N/A
Copper (d)(h) 2.9 3.9 0.348 8.30 11.17
automatically inserted into Table 2 and are the allowable
Total Metal allocations determined for the Permittee prior
Lead d h 0.58 15 0.184 3.15 81.52
Nickel (d)(h) 17 154 0.432 39.20 355.16
to allowing for dilution. See Input sheet Table 2. The final
Ni - WS streams t 25 N/A
acute and chronic values shown under the RPA sheet are
Silver d h,acute 0.06 0.33 1.000 0.06 0.33
the Total Metal values listed in Table 2 divided by the
Zinc (d)(h) 38 38 0.288 133.46 133.20
acute and chronic IWC, respectively.
2) The Translators used in the freshwater RPA are the
Partition Coefficients published by US EPA in 1984. They
Beryllium
6.5
65 1.000 6.5 65
Arsenic (d)
1501
3401 1.0001 15011340
are TSS dependent equations and can be found listed with
(d) = dissolved metal standard. See 15A NCAC 026.0211 f -ore information.
the WQS hardness dependent equations under the sheet
(h)=hardness-dependeutdisgolvedmetal standard. See 15ANCACO2B.0211formoreinformation.
labeled Equations. A fixed TSS value of 10 mg/L is used to
(t) = basedupon measurement oftotal recoveable metal. See 15ANCAC 02B.0211 for more information.
calculate the Translator values.
The Human Health standard for Nickel in Water Supply Streams is 25 mg/L which is Total Recoverable metal standard.
3) Pretreatment Facilities- PERCS will need a copy of the
The Human Health standard for Arsenic is 10 pg/L which is Total Recoverable metal standard.
Dissolved to Total Metal Calculator spreadsheet and the
RPA sheet along with the Final Permit. Pretreatment
Facilities are required to renew their Headwords Analysis
after renewal of their permits. Since all their metal
allocations are likely to change PERCS needs to see any
new metal permit limits and the allowable allocations for
the dissolved metals to assess Maximum Allowable
Headworks Loading (MAHL) numbers for each metal based
on the Combined Hardness values used in the permit
writers RPA calculations.
4) For Cadmium, Lead, Nickel, Chromium and Beryllium, if
all the effluent sampling data for the last three to five
years shows the pollutant at concentrations less than the
Practical Quantitative Level (PQL), it is not likely a limit or
monitoring will be put in the permit. However, if the
estimated NPDES permit limit is less than the Practical
Quantitative Limit (particularly, Cadmium and Lead) and
the pollutant is believed to be present, to assess
compliance with the new standards and for future permit
limit development, monitoring for the pollutant will be
required. If the facility is monitoring for the pollutant in its
Pretreatment LTMP, no monitoring is needed in the
permit.
Inet-on Upstream Effluent
Wastewater Hardness
Concentratim Hardness Average
(Acute) Average (mg/L) (mg/l-)
earn vara rvg kn1l = zo
EFF Hard Avg (mg/L) = 29.66667