permit fact sheet general information · 6/5/1984 · notes prop comp mercury, total recoverable...

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Permit Fact Sheet

General Information

Permit Number: WI-0028541-09-0

Permittee Name: CITY OF WATERTOWN

Address: 800 Hoffman Dr

City/State/Zip: Watertown WI 53094

Discharge Location: West Bank 4,850 feet downstream of Hwy Bus. 26 bridge in the NE ¼ of SE ¼ of

Section 8, T8N, R15E

Receiving Water: Rock River (Middle Rock River Watershed, UR01 – Upper Rock River Basin) in

Jefferson County

StreamFlow (Q7,10): Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

7-Q10

(cfs) 45 56 109 278 109 48 30 22 20 21 45 47

7-Q2

(cfs) 169 184 440 819 365

18

0

10

9 86 77 102 193 184

Stream Classification: Warm Water Sport Fishery (WWSF), non-public water supply

Design Flow(s) Annual

Average

Design Flow(s)

Significant Industrial

Loading?

Yes, Waste Pak (Pepsi Co.), Johnsonville (Butcher Co.), Western Industries, Ad Tech,

Clasen Quality, Diversey

Operator at Proper Grade? Yes, required: Advanced – A1, B, C, D, P & SS. SS is required by the end if this

permit term.

Approved Pretreatment

Program?

June 5, 1984

Facility Description

The City of Watertown operates a recently upgraded (2002-2004) wastewater treatment facility serving a population of

23,655 designed to treat a daily flow of 5.2 MGD of domestic, commercial and industrial wastewater. The plant currently

receives approximately 3.2-3.5 MGD for treatment. The facility consists of parallel bar screens and grit removal, two

primary clarifiers followed by a splitter box to three activated sludge tanks with an anoxic selector in the front of the

basins. At the end of the tanks ferric chloride is added to bind up phosphorus and then the flow goes to two final clarifiers,

UV disinfection and step aeration prior to discharge to the Rock River. Waste sludge is co-settled in the primary clarifiers

and all sludge is pumped into anaerobic digesters. Digesters are heated to 95-98 degrees F and mixed with draft tube

mixers. Once processed, sludge is pumped to centrifuges that thicken the sludge to ~23-28% solids and then to sludge

storage and finally hauled and land applied to DNR-approved farm fields to the agronomic needs of the cover crop. Over

180 days of sludge storage is available. BLENDING: The permittee has requested blending approval as part of their

permit application. Based on an evaluation of their request and associated documentation, blending is approved per s. NR

210.12(2), Wis. Adm. Code.

The permittee has been found to be in substantial compliance with its current permit. Shaded cells below indicate changes.

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Sample Point Designation

Sample

Point

Number

Discharge Flow, Units, and

Averaging Period

Sample Point Location, WasteType/sample Contents and

Treatment Description (as applicable)

701 4.25 MGD (2019) Influent: 24-Hr flow proportional sampler located after raw influent

screening. Flow meter located after raw wastewater pumps.

001 4.12 MGD (2019) Effluent: 24-Hr flow proportional sampler located prior to UV

disinfection. Grab samples taken post aeration prior to discharge to

the Rock River.

002 N/A Representative samples of class B, anaerobically digested liquid

sludge shall be collected from the secondary digester, if this sludge

is land applied. If this sample point is activated, the sludge shall be

analyzed for List 2 parameters (Nutrients) just prior to land

application and DNR shall be notified prior to land application.

004 401 MT (2017-2019) Representative samples of class B, anaerobically digested cake

sludge shall be collected from the centrifuge.

102 <0.12 ng/L (2019) Collect the mercury field blank using sample handling procedures

specified in NR 106.145(9), Wisconsin Administrative Code.

103 4.25 MGD (2019) Sample point for reporting diverted flow from the primary clarifiers

during high flow events. Flow bypasses the aeration basins and final

clarifiers but receives disinfection prior to discharge. Department

approval for blending shall be obtained prior to use of this sample

point. Any flow diverted prior to blending approval shall be

considered to be a bypass, is prohibited, and should be reported to

the Department as such. The permittee shall notify the Department

when blending occurs. See Blending requirements in the Standard

Requirements section of the permit.

1 Influent - Proposed Monitoring

Sample Point Number: 701- INFLUENT

Monitoring Requirements and Limitations

Parameter Limit Type Limit and

Units

Sample

Frequency

Sample

Type

Notes

Flow Rate MGD Daily Continuous

BOD5, Total mg/L 5/Week 24-Hr Flow

Prop Comp

Suspended Solids,

Total

mg/L 5/Week 24-Hr Flow

Prop Comp

Cadmium, Total

Recoverable

ug/L Quarterly 24-Hr Flow

Prop Comp

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Units

Sample

Frequency

Sample

Type

Notes

Chromium, Total

Recoverable


Prop Comp

Copper, Total

Recoverable


Prop Comp

Lead, Total

Recoverable


Prop Comp

Nickel, Total

Recoverable


Prop Comp

Zinc, Total

Recoverable


Prop Comp

Mercury, Total

Recoverable

ng/L Quarterly 24-Hr Flow

Prop Comp

Changes from Previous Permit:

Flow frequency changed to ‘daily’ from ‘continuous’ for consistency and eDMR reporting purposes. Metals sampling

frequency changed to quarterly throughout the full permit term. Mercury influent sampling increased to monthly.

Explanation of Limits and Monitoring Requirements

BOD5 and Total Suspended Solids: Tracking of BOD5, and Suspended Solids are required for percent removal

requirements found in s. NR 210.05, Wis. Adm. Code and in the Standard Requirements section of the permit.

Metals: Quarterly metals sampling throughout the permit term is required for permittees with approved pretreatment

programs.

Mercury, Total Recoverable: Mercury monitoring is included in the proposed permit pursuant to s. NR 106.145, Wis.

Adm. Code. Required field blanks for Mercury monitoring per ss. NR 106.145(9) and (10), Wis. Adm. Code,

requirements. The permittee shall collect a mercury field blank for each set of mercury samples (a set of samples may

include a combination of influent, effluent or other samples all collected on the same day). The permittee shall report

results of influent and effluent samples and field blanks to the Department on Discharge Monitoring Reports.

2 Inplant - Proposed Monitoring and Limitations

Sample Point Number: 102- GEN PLANT (Hg blank)



Units

Sample

Frequency

Sample

Type

Notes

Mercury, Total

Recoverable

ng/L Quarterly Blank See Mercury Monitoring

section


No changes made.


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Required field blanks for Mercury monitoring per ss. NR 106.145(9) and (10), Wis. Adm. Code, requirements. The

permittee shall collect a mercury field blank for each set of mercury samples (as set of samples may include a

combination of influent, effluent or other samples all collected on the same day). The permittee shall report results of

influent and effluent samples and field blanks to the Department on Discharge Monitoring Reports.

Sample Point Number: 103- BLENDING



Units

Sample

Frequency

Sample

Type

Notes

Flow Rate MGD Per

Occurrence

Continuous See Blending Flow permit

section.

Time hours Per

Occurrence

Calculated Report the total duration of

blending within a given day

(12:00 am - 11:59 pm) in

which blending occurs. See

Blending Flow permit

section.


The permittee requested blending as part of the permit application. Blending requirements including reporting

requirements added.


Blending requires approval by the Department and reporting of flow rate and time per occurrence of blending. The

Approval for blending is required upon each permit reissuance. See Standard Requirements section of the permit for

additional requirements. Department has determined that blending as defined in s. NR 210.03 (2e), Wis. Adm. Code, may

occur at this sewage treatment facility.

3 Surface Water - Proposed Monitoring and Limitations

Sample Point Number: 001- EFFLUENT



Units

Sample

Frequency

Sample

Type

Notes

Flow Rate MGD Daily Continuous

BOD5, Total Monthly Avg 30 mg/L 5/Week 24-Hr Flow

Prop Comp

Effective January through

May


Prop Comp

Effective June


Prop Comp

Effective July and October


Prop Comp

Effective August and

September

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Units

Sample

Frequency

Sample

Type

Notes


Prop Comp

Effective November


Prop Comp

Effective December

BOD5, Total Weekly Avg 31 mg/L 5/Week 24-Hr Flow

Prop Comp

Effective January


Prop Comp

Effective February


Prop Comp

Effective March through

May


Prop Comp

Effective June


Prop Comp



Prop Comp


September


Prop Comp

Effective November


Prop Comp

Effective December

BOD5, Total Weekly Avg 1,400 lbs/day 5/Week Calculated Effective January

BOD5, Total Weekly Avg 1,500 lbs/day 5/Week Calculated Effective February

BOD5, Total Weekly Avg 690 lbs/day 5/Week Calculated Effective June

BOD5, Total Weekly Avg 530 lbs/day 5/Week Calculated Effective July and October

BOD5, Total Weekly Avg 450 lbs/day 5/Week Calculated Effective August

BOD5, Total Weekly Avg 440 lbs/day 5/Week Calculated Effective September

BOD5, Total Weekly Avg 1,100 lbs/day 5/Week Calculated Effective November

BOD5, Total Weekly Avg 1,300 lbs/day 5/Week Calculated Effective December

Suspended Solids,

Total

Monthly Avg 30 mg/L 5/Week 24-Hr Flow

Prop Comp

Effective January through

May

Suspended Solids,

Total


Prop Comp

Effective June

Suspended Solids,

Total


Prop Comp


Suspended Solids, Monthly Avg 10 mg/L 5/Week 24-Hr Flow Effective August and

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Units

Sample

Frequency

Sample

Type

Notes

Total Prop Comp September

Suspended Solids,

Total


Prop Comp

Effective November

Suspended Solids,

Total


Prop Comp

Effective December

Suspended Solids,

Total

Weekly Avg 31 mg/L 5/Week 24-Hr Flow

Prop Comp

Effective January

Suspended Solids,

Total


Prop Comp

Effective February

Suspended Solids,

Total


Prop Comp

Effective March through

May

Suspended Solids,

Total


Prop Comp

Effective June

Suspended Solids,

Total


Prop Comp


Suspended Solids,

Total


Prop Comp


September

Suspended Solids,

Total


Prop Comp

Effective November

Suspended Solids,

Total


Prop Comp

Effective December

Suspended Solids,

Total

Monthly Avg 1,270 lbs/day 5/Week Calculated Effective January, March,

and May

Suspended Solids,

Total

Monthly Avg 1,410 lbs/day 5/Week Calculated Effective February

Suspended Solids,

Total

Monthly Avg 1,310 lbs/day 5/Week Calculated Effective April

Suspended Solids,

Total

Monthly Avg 700 lbs/day 5/Week Calculated Effective June

Suspended Solids,

Total

Monthly Avg 510 lbs/day 5/Week Calculated Effective July and October

Suspended Solids,

Total

Monthly Avg 430 lbs/day 5/Week Calculated Effective August

Suspended Solids,

Total

Monthly Avg 440 lbs/day 5/Week Calculated Effective September

Suspended Solids, Monthly Avg 1,100 lbs/day 5/Week Calculated Effective November

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Units

Sample

Frequency

Sample

Type

Notes

Total

Suspended Solids,

Total

Monthly Avg 1,230 lbs/day 5/Week Calculated Effective December

Suspended Solids,

Total

Weekly Avg 1,400 lbs/day 5/Week Calculated Effective January

Suspended Solids,

Total

Weekly Avg 1,500 lbs/day 5/Week Calculated Effective February

Suspended Solids,

Total

Weekly Avg 2,270 lbs/day 5/Week Calculated Effective March and May

Suspended Solids,

Total

Weekly Avg 2,340 lbs/day 5/Week Calculated Effective April

Suspended Solids,

Total

Weekly Avg 690 lbs/day 5/Week Calculated Effective June

Suspended Solids,

Total

Weekly Avg 530 lbs/day 5/Week Calculated Effective July and October

Suspended Solids,

Total

Weekly Avg 450 lbs/day 5/Week Calculated Effective August

Suspended Solids,

Total

Weekly Avg 440 lbs/day 5/Week Calculated Effective September

Suspended Solids,

Total

Weekly Avg 1,100 lbs/day 5/Week Calculated Effective November

Suspended Solids,

Total

Weekly Avg 1,300 lbs/day 5/Week Calculated Effective December

Nitrogen, Ammonia

(NH3-N) Total

Daily Max 20 mg/L 5/Week 24-Hr Flow

Prop Comp

Effective November

through March

Nitrogen, Ammonia

(NH3-N) Total


Prop Comp

Effective November

through March

Nitrogen, Ammonia

(NH3-N) Total


Prop Comp

Effective June

Nitrogen, Ammonia

(NH3-N) Total

Weekly Avg 9.0 mg/L 5/Week 24-Hr Flow

Prop Comp

Effective July

Nitrogen, Ammonia

(NH3-N) Total


Prop Comp

Effective August

Nitrogen, Ammonia

(NH3-N) Total


Prop Comp

Effective September

Nitrogen, Ammonia Weekly Avg 13 mg/L 5/Week 24-Hr Flow Effective October

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Units

Sample

Frequency

Sample

Type

Notes

(NH3-N) Total Prop Comp

Nitrogen, Ammonia

(NH3-N) Total


Prop Comp

Effective November

through March

Nitrogen, Ammonia

(NH3-N) Total


Prop Comp

Effective June

Nitrogen, Ammonia

(NH3-N) Total

Monthly Avg 9.0 mg/L 5/Week 24-Hr Flow

Prop Comp

Effective July

Nitrogen, Ammonia

(NH3-N) Total


Prop Comp

Effective August

Nitrogen, Ammonia

(NH3-N) Total


Prop Comp

Effective September

Nitrogen, Ammonia

(NH3-N) Total


Prop Comp

Effective October

Dissolved Oxygen Daily Min 6.0 mg/L Daily Grab

pH Field Daily Max 9.0 su Daily Grab

pH Field Daily Min 6.0 su Daily Grab

Fecal Coliform Geometric

Mean -

Monthly

400 #/100 ml 2/Week Grab Interim limit effective May

– September annually until

the final E. coli limit goes

into effect per the “Effluent

Limitations for E. coli”

Schedule.

E. coli #/100 ml 2/Week Grab Monitoring only May –

September annually until

the final limit goes into

effect per the “Effluent

Limitations for E. coli”

Schedule.

E. coli Geometric

Mean -

Monthly

126 #/100 ml 2/Week Grab Limit Effective May –

September annually per the

“Effluent Limitations for E.

coli” Schedule.

E. coli % Exceedance 10 Percent Monthly Calculated Limit Effective May –

September annually per the

“Effluent Limitations for E.

coli” Schedule. See the “E.

coli Percent Limit” section

below. Enter the result in

the DMR on the last day of

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Units

Sample

Frequency

Sample

Type

Notes

the month.

Phosphorus, Total Monthly Avg 0.8 mg/L 5/Week 24-Hr Flow

Prop Comp

This is an interim MDV

limit effective upon

reissuance. See the

MDV/Phosphorus

subsections and phosphorus

schedules.

Phosphorus, Total Monthly Avg 13.7 lbs/day Monthly Calculated Effective January starting

in 2022

Phosphorus, Total Monthly Avg 19.5 lbs/day Monthly Calculated Effective February starting

in 2022

Phosphorus, Total Monthly Avg 18.4 lbs/day Monthly Calculated Effective March starting in

2022

Phosphorus, Total Monthly Avg 16.5 lbs/day Monthly Calculated Effective May starting in

2022

Phosphorus, Total Monthly Avg 17.7 lbs/day Monthly Calculated Effective July starting in

2021

Phosphorus, Total Monthly Avg 16.2 lbs/day Monthly Calculated Effective August starting in

2021

Phosphorus, Total Monthly Avg 14.8 lbs/day Monthly Calculated Effective September

starting in 2021

Phosphorus, Total Monthly Avg 12.3 lbs/day Monthly Calculated Effective October and

November starting in 2021

Phosphorus, Total Monthly Avg 11.9 lbs/day Monthly Calculated Effective December starting

in 2021

Phosphorus, Total lbs/month Monthly Calculated Report the total monthly

phosphorus discharged in

lbs/month on the last day of

the month on the DMR. See

Standard Requirements for

'Appropriate Formulas' to

calculate the Total Monthly

Discharge in lbs/month.

Phosphorus, Total lbs/yr Annual Calculated Report the sum of the total

monthly discharges (for the

months that the MDV is in

effect) for the calendar year

on the Annual report form.

Chloride mg/L 4/Month 24-Hr Flow Monitoring only in 2024

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Units

Sample

Frequency

Sample

Type

Notes

Prop Comp

Mercury, Total

Recoverable

Daily Max 3.7 ng/L Quarterly Grab This is an Alternative

Mercury Effluent Limit.

See Mercury section and

schedule.

Temperature

Maximum

3/Week Continuous

Acute WET TUa See Listed

Qtr(s)

24-Hr Flow

Prop Comp

See WET section.

Chronic WET Monthly Avg 1.5 TUc See Listed

Qtr(s)

24-Hr Flow

Prop Comp

See WET section.

Cadmium, Total

Recoverable


Prop Comp

Chromium, Total

Recoverable


Prop Comp

Copper, Total

Recoverable


Prop Comp

Lead, Total

Recoverable


Prop Comp

Nickel, Total

Recoverable


Prop Comp

Zinc, Total

Recoverable


Prop Comp

Nitrogen, Total

Kjeldahl

mg/L Quarterly 24-Hr Flow

Prop Comp

Nitrogen, Nitrite +

Nitrate Total

mg/L Quarterly 24-Hr Flow

Prop Comp

Nitrogen, Total mg/L Quarterly Calculated Total Nitrogen shall be

calculated as the sum of

reported values for Total

Kjeldahl Nitrogen and

Total Nitrite + Nitrate

Nitrogen.

Changes from Previous Permit

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Flow sample frequency changed to daily from continuous for eDMR reporting purposes. Weekly and monthly average

ammonia limits updated. Phosphorus limits updated including MDV requirements added. Temperature monitoring year

round upon reissuance per the approved DC study (this change was made and the permit re-public noticed). Nitrogen

series monitoring added. Metals sampling updated to quarterly throughout the full permit term.

The permittee has applied for a multi-discharger variance (MDV) for phosphorus for this permit term only for April and

June and the application has been approved by the Department. An MDV interim limit of 0.8 mg/L has been included.

The permittee is now required to report the total amount of phosphorus discharged in lbs/month and lbs/year. By March 1

of each year the permittee shall make a payment(s) to participating county(s) of $54.23 per pound of phosphorus

discharged during the previous year in excess of the target value of 0.2 mg/L. For all other months, TMDL phosphorus

limits are effective starting July 1, 2021.

Fecal coliform monitoring and limits have been replaced with Escherechia coli (E. coli) monitoring and limits. E. coli

monitoring is required at the permit effective date. An interim fecal coliform limit of 400 #/100 ml as a monthly geometric

mean will apply from the permit effective date through the end of a compliance schedule. At the end of the compliance

schedule, E. coli limits of 126 #/100 ml as a monthly geometric mean that may never be exceeded and 410 #/100 ml as a

daily maximum that may not be exceeded more than 10 percent of the time in any calendar month will apply.

Explanation of Limits and Monitoring Requirements Water Quality Based Limits and WET Requirements and Disinfection (if applicable)

Refer to the WQBEL memo for the detailed calculations, prepared by Sarah Luck dated September 20, 2019, WQBEL

addendum for temperature dated October 23, 2019 and the WQBEL addendum for E. coli limits dated May 1, 2020 used

for this reissuance.

BOD5, pH, DO, Fecal Coliform, and Total Suspended Solids – The categorical limitations for BOD5, TSS, pH and DO

are carried over into this permit. These limitations are not subject to change at this time because the receiving water

characteristics have not changed. On May 1, 2020 revisions to the bacteria surface water criteria became effective.

Therefore, this permit has been updated to include the existing fecal coliform limit as an interim limit along with E-coli

monitoring and a compliance schedule to meet required E. coli limits. The interim fecal coliform limit is effective until the

final E. coli limit becomes effective per the Schedule.

E. Coli & Fecal Coliform - Revisions to bacteria surface water quality criteria to protect recreational uses and

accompanying E. coli WPDES permit implementation procedures became effective May 1, 2020. See changes from

previous permit above and the e-coli WQBEL addendum for more information. The new rule requires that WPDES

permits for facilities with required disinfection include monitoring for E. coli while facilities are disinfecting during the

recreation period, and establish effluent limitations for E. coli established in s. NR 210.06 (2), Wis. Adm Code. The

administrative code rule changes included the following actions: revised the bacteria water quality criteria from fecal

coliform to E. coli to protect recreation in ch. NR 102, Wis. Adm. Code.; removed fecal coliform criteria for certain

individual waters from ch. NR 104, Wis. Adm. Code.; revised permit requirements for publicly and privately owned

sewage treatment works in ch. NR 210, Wis. Adm. Code.; and, updated approved analytical methods for bacteria in ch.

NR 219, Wis. Adm. Code.

Ammonia – Current acute and chronic ammonia toxicity criteria for the protection of aquatic life are included in Table 2C

and Table 4B of ch. NR 105, Wis. Adm. Code (effective March 1, 2004). Subchapter IV of ch. NR 106 establishes

procedures for calculating water quality-based effluent limitations (WQBELs) for ammonia (effective March 1, 2004).

Weekly average and monthly average ammonia limits are required in accordance with the federal regulation 40 CFR

122.45(d), limits in this permit are to be expressed as weekly average and monthly average limits whenever practicable.

See limit memo for month by month explanation of ammonia limits.

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Rock River Total Maximum Daily Load - The City of Watertown WWTP is in the Rock River Basin. A total

maximum daily load (TMDL) was developed for the Rock River Basin to determine the maximum amounts of phosphorus

and sediment that can be discharged to protect and improve water quality. The Rock River Basin’s TMDL was approved

by the Environmental Protection Agency (EPA) in September 2011. These final effluent limits were derived from and

comply with the applicable water quality criterion and are consistent with the assumptions and requirements of the EPA-

approved waste load allocation (WLA) for the Rock River. The entire report can be found at:

http://dnr.wi.gov/topic/TMDLs/RockRiver/Final_Rock_River_TMDL_Report_with_Tables.pdf. The proposed permit

includes limitations and requirements necessary to implement the recommendations of the TMDL. For specific limits see

below.

Phosphorus – Phosphorus rules became effective December 1, 2010 per NR 217, Wis. Adm. Code, that required the

permittee to comply with water quality based effluent limits (WQBELs) for total phosphorous. For this permit term, the

permittee has applied for the Multi-Discharger Variance (MDV) for phosphorus as provided for in s. 283.16, Wis. Stats.,

and approved by USEPA on February 6, 2017 until February 5, 2027. The permittee qualifies for the MDV in the months

of April and June for the TMDL derived limit because it is an existing source and a major facility upgrade is needed to

comply with the applicable phosphorus WQBELs, thereby creating a financial burden. The effluent limit for total

phosphorus is 0.8 mg/L as an average monthly limit and is effective upon reissuance. The limit was derived using DMR

data from October 2014 to April 2019. TMDL limits for January through March, May, and July through December are

effective starting June 2021.

Conditions of the MDV require the permittee to optimize phosphorus removal throughout the proposed permit term,

comply with interim limits and make annual payments to participating county(s) by March 1 of each year based on the

pounds of phosphorus discharged during the previous year in excess of the specified target value. The “price per pound”

value is $50.00 adjusted for CPI annually during the first quarter as defined by s. 283.16(8)(a)2, Wis. Stats and takes

effect for reissued permits with effective dates starting April 1. This may differ from the “price per pound” that is public

noticed; however, the “price per pound” is set upon reissuance and is applicable for the entire permit term. The

participating county(s) uses these payments to implement non-point source (agricultural and urban) phosphorus control

strategies at the watershed level.

Rock River TMDL Total Phosphorus - Mass limits were calculated to comply with the Rock River TMDL and were

derived consistent with the assumptions and requirements of the EPA-approved WLA for the Rock River. Limits for the

permit were determined using the code changes and the provisions of the TMDL. The final effluent mass limits for

phosphorus are expressed as monthly averages and is effective for all months starting July 1, 2021 (except April and June,

see MDV). The approved total phosphorus TMDL mass limits for this permittee are included in the following table below:

Month

Monthly Average

Total P Effluent Limit

(lbs/day)

Jan 13.7

Feb 19.5

March 18.4

April 18.3

May 16.5

June 17.6

July 17.7

Aug 16.2

Sept 14.8

Oct 12.3

Nov 12.3

http://dnr.wi.gov/topic/TMDLs/RockRiver/Final_Rock_River_TMDL_Report_with_Tables.pdf

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Month

Monthly Average

Total P Effluent Limit

(lbs/day)

Dec 11.9

Total Suspended Solids - Weekly average and monthly average mass limits for total suspended solids were required to

comply with the Rock River TMDL and were derived consistent with the assumptions and requirements of the EPA-

approved WLA for the Rock River. The current permit contains weekly TSS mass limits for the months of June through

February that are more stringent than the TMDL limits for those same months. Due to antidegradation rules (NR 207,

Wis. Adm. Code), these more stringent limits will be retained in the reissued permit in lieu of the weekly average TMDL

limits for the months of June through February. The calculated weekly average TSS TMDL limits for March through

April, and the monthly average TSS TMDL limits for January through December are retained. There are no changes

proposed in current concentration limits. These limits are in addition to the concentration limits for suspended solids in the

current permit, which vary from 10 mg/L to 30 mg/L as a monthly average and from 10 mg/L to 45 mg/L as a weekly

average. The approved total suspended solids TMDL limits for this permittee are included in the following table,

expressed as weekly average and monthly average effluents limits, and remain in effect except as superseded by more

stringent water quality based effluent limits:

Total Suspended Solids Effluent Limitations

Month

Monthly Average

TMDL TSS

Effluent Limit

(lbs/day)

Weekly Average

TMDL TSS

Effluent Limit

(lbs/day)

Weekly Average

TSS Effluent Limit

in Current Permit

(lbs/day)

Effective Weekly

Average TSS

Effluent Limit

(lbs/day)

Jan 1270 2270 1400 1400

Feb 1410 2500 1500 1500

March 1270 2270 -- 2270

April 1310 2340 -- 2340

May 1270 2270 -- 2270

June 700 1250 690 690

July 510 910 530 530

Aug 430 760 450 450

Sept 440 770 440 440

Oct 510 910 530 530

Nov 1100 1950 1100 1100

Dec 1230 2190 1300 1300

Chloride - When the representative data is compared to the calculated limits, the data shows there is no reasonable

potential for the permittee to exceed the calculated limits. Therefore, no chloride limits are included in the proposed

permit. However, the permittee shall monitor effluent chloride concentrations frequently enough to ensure adequate data

for permit reissuance.

Mercury – Watertown applied for and was granted an alternative mercury effluent limit of 3.7 ng/L for the current permit

term. Watertown implemented a mercury pollutant minimization program (PMP) during the current permit term and was

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successful at reducing mercury effluent concentrations. An analysis of mercury effluent data generated during the current

permit term (P99s) show that Watertown is still unable to consistently meet the wildlife water quality criterion of 1.3

ng/L. Watertown has applied for another variance from the mercury water quality standards, which requires EPA

approval. If granted, the mercury variance limit will remain as 3.7 ng/L as a daily maximum and continued

implementation of Watertown’s mercury PMP will be required. Mercury influent, effluent and sludge monitoring is

required along with the collection and analysis of at least one field blank shall be collected at each site for each day a

sample is collected. See the schedules section for the mercury schedule. Requirements for mercury are included in s. NR

106.145, Wis. Adm. Code.

Temperature: Requirements for Temperature are included in NR 102 Subchapter II Water Quality Standards for

Temperature and NR 106 Subchapter V Effluent Limitations for Temperature. Thermal discharges must meet the Public

Health criterion of 120 degrees F and the Fish & Aquatic Life criteria which are established to protect aquatic

communities from lethal and sub-lethal thermal effects. Final water quality based effluent limits for the month of October

was required per the WQBEL. The proposed permit was public noticed with a schedule for submittal of a DC study and

this limit to become effective during the permit term. The Department has since approved a DC study and therefore re-

public noticed the permit with removal of the temperature limits and schedule to submit the DC study. Monitoring 3/week

throughout the permit term is required and the DC study will need to be reevaluated at the time of the next permit

reissuance.

Whole Effluent Toxicity: Whole effluent toxicity (WET) testing requirements and limits (if applicable) are determined in

accordance with ss. NR 106.08 and NR 106.09 Wis. Adm. Code, as revised August 2016. (See the current version of the

Whole Effluent Toxicity Program Guidance Document and checklist and WET information, guidance and test methods at

http://dnr.wi.gov/topic/wastewater/wet.html). Annual WET testing in rotating quarters is required as listed in the permit.

Toxics – Metals monitoring throughout the permit term is required for all permittee’s with approved pretreatment

programs. Sampling is required quarterly year-round throughout the permit term.

Total Nitrogen Monitoring (NO2+NO3, TKN and Total N): The Department has included effluent monitoring for

Total Nitrogen in the permit through the authority under §§ 283.55(1)(e), Wis. Stats., which allows the department to

require the permittee to submit information necessary to identify the type and quantity of any pollutants discharged from

the point source, and through s. NR 200.065(1)(h), Wis. Adm. Code, which allows for this monitoring to be collected

during the permit term. Quarterly effluent monitoring for Total Nitrogen is included in the permit because of the potential

for higher nitrogen loading resulting from higher flows (major facilities), higher concentrations, or both. More

information on the justification to include total nitrogen monitoring in wastewater permits can be found in the “Guidance

for Total Nitrogen Monitoring in Wastewater Permits” dated October 1, 2019.

http://dnr.wi.gov/topic/wastewater/wet.html

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4 Land Application - Proposed Monitoring and Limitations Municipal Sludge Description

Sample

Point

Sludge

Class (A or

B)

Sludge

Type

(Liquid or

Cake)

Pathogen

Reduction

Method

Vector

Attraction

Method

Reuse

Option

Amount

Reused/Dis

posed (Dry

Tons/Year)

002 B Liquid Fecal

Coliform &

Anaerobic

Digestion

Volatile

Solids

Reduction

Land

Application

Inactive

004 B Cake Fecal

Coliform &

Anaerobic

Digestion

Volatile

Solids

Reduction &

Incorporatio

n

Land

Application

401 MT

(2017-2019)

Does sludge management demonstrate compliance? Yes

Is additional sludge storage required? No

Is Radium-226 present in the water supply at a level greater than 2 pCi/liter? Yes

If yes, special monitoring and recycling conditions will be included in the permit to track any potential

problems in landapplying sludge from this facility

Is a priority pollutant scan required? Yes, see permit

Priority pollutant scans are required once every 10 years at facilities with design flows between 5 MGD

and 40 MGD, and once every 5 years if design flow is greater than 40 MGD.

Sample Point Number: 002- LIQUID SLUDGE and 004- CAKE SLUDGE



Units

Sample

Frequency

Sample

Type

Notes

Solids, Total Percent Quarterly Composite

Arsenic Dry Wt Ceiling 75 mg/kg Quarterly Composite

Arsenic Dry Wt High Quality 41 mg/kg Quarterly Composite

Cadmium Dry Wt Ceiling 85 mg/kg Quarterly Composite

Cadmium Dry Wt High Quality 39 mg/kg Quarterly Composite

Copper Dry Wt Ceiling 4,300 mg/kg Quarterly Composite

Copper Dry Wt High Quality 1,500 mg/kg Quarterly Composite

Lead Dry Wt Ceiling 840 mg/kg Quarterly Composite

Lead Dry Wt High Quality 300 mg/kg Quarterly Composite

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Units

Sample

Frequency

Sample

Type

Notes

Mercury Dry Wt Ceiling 57 mg/kg Quarterly Composite

Mercury Dry Wt High Quality 17 mg/kg Quarterly Composite

Molybdenum Dry Wt Ceiling 75 mg/kg Quarterly Composite

Nickel Dry Wt Ceiling 420 mg/kg Quarterly Composite

Nickel Dry Wt High Quality 420 mg/kg Quarterly Composite

Selenium Dry Wt Ceiling 100 mg/kg Quarterly Composite

Selenium Dry Wt High Quality 100 mg/kg Quarterly Composite

Zinc Dry Wt Ceiling 7,500 mg/kg Quarterly Composite

Zinc Dry Wt High Quality 2,800 mg/kg Quarterly Composite

Nitrogen, Total

Kjeldahl

Percent Quarterly Composite

Nitrogen, Ammonium

(NH4-N) Total


Phosphorus, Total Percent Quarterly Composite

Phosphorus, Water

Extractable

% of Tot P Quarterly Composite

Potassium, Total

Recoverable


Radium 226 Dry Wt pCi/g Annual Composite

PCB Total Dry Wt Ceiling 50 mg/kg Once Composite Monitor for PCB's as part

of the priority pollutant

scan in 2022.

PCB Total Dry Wt High Quality 10 mg/kg Once Composite Monitor for PCB's as part

of the priority pollutant

scan in 2022.

Municipal Sludge

Priority Pollutant

Scan

Once Composite As specified in ch. NR

215.03 (1-4), Wis. Adm.

Code.


No changes made.


Municipal sludge priority pollutant scan shall be completed in 2022 along with PCB testing. Requirements for land

application of municipal sludge are determined in accordance with ch. NR 204 Wis. Adm. Code. Ceiling and high quality

limits for metals in sludge are specified in s. NR 204.07(5), Wis. Adm. Code. Requirements for pathogens are specified

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in s. NR 204.07(6) and in s. NR 204.07 (7), Wis. Adm. Code for vector attraction requirements. Limitations for PCBs are

addressed in s. NR 204.07(3)(k), Wis. Adm. Code.

5 Schedules

5.1 Mercury Pollutant Minimization Program As a condition of the variance to the water quality based effluent limitation(s) for mercury granted in accordance with s.

NR 106.145(6), Wis. Adm. Code, the permittee shall perform the following actions.

Required Action Due Date

Annual Mercury Progress Reports: Submit an annual mercury progress report. The annual mercury

progress report shall:

Indicate which mercury pollutant minimization activities or activities outlined in the approved

Pollutant Minimization Plan have been implemented;

Include an analysis of trends in monthly and annual total effluent mercury concentrations based on

mercury sampling; and

Include an analysis of how influent and effluent mercury varies with time and with significant

loading of mercury such as loads from industries into the collection system.

The first annual mercury progress report is to be submitted by the Due Date.

01/31/2021

Annual Mercury Progress Report #2: Submit a mercury progress report as defined above. 01/31/2022



Final Mercury Report: Submit a final report documenting the success in reducing mercury

concentrations in the effluent, as well as the anticipated future reduction in mercury sources and

mercury effluent concentrations. The report shall summarize mercury pollutant minimization

activities that have been implemented during the current permit term and state which, if any, pollutant

minimization activities from the approved pollutant minimization plan were not pursued and why.

The report shall include an analysis of trends in monthly and annual total effluent mercury

concentrations based on mercury sampling during the current permit term. The report shall also

include an analysis of how influent and effluent mercury varies with time and with significant loading

of mercury such as loads from industries into the collection system.

If the permittee intends to reapply for a mercury variance per s. NR 106.145, Wis. Adm. Code, for the

reissued permit, a detailed pollutant minimization plan outlining the pollutant minimization activities

proposed for the upcoming permit term shall be submitted along with the final report.

01/31/2025

Annual Mercury Reports After Permit Expiration: In the event that this permit is not reissued on time,

the permittee shall continue to submit annual mercury reports each year covering pollutant

minimization activities implemented and mercury concentration trends.

Explanation of Schedule

Watertown has applied for a variance from the mercury water quality criterion for the protection of wildlife (1.3 ng/L). As

a condition of receiving a mercury variance, s. NR 106.145(7), Wis. Adm. Code, requires the permittee to continue to

develop and implement a Mercury Pollutant Minimization Program (PMP). The schedule requires the permittee to

implement the Mercury PMP and submit annual status reports on PMP activities. Annual status reports are required to be

submitted by January 31st of the following year, regardless of whether or not the permit expires without being reissued.

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5.2 Phosphorus Schedule - Optimization Plan The permittee is required to optimize performance to control phosphorus discharges per the following schedule.


Optimization Plan: The permittee shall prepare an Optimization Plan and submit it for Department

approval. The plan shall include an evaluation of collected effluent data, possible source reduction

measures and operational improvements to optimize performance to control phosphorus discharges.

The plan shall contain a schedule for implementation of the measures and improvements. Once the

plan is approved by the Department, the permittee shall take the steps called for in the Optimization

Plan and follow the schedule of implementation as approved.

06/30/2021

Progress Report #1: Submit a progress report on optimizing removal of phosphorus. 06/30/2022





Per s. 283.16(6)(a), Wis. Stats. the Department may include a requirement that the permittee optimize the performance of

a point source in controlling phosphorus discharges, which may be necessary to achieve compliance with multi-discharger

variance interim limits. This compliance schedule requires the permittee to continue to implement the optimization plan

that was approved during the previous permit term.

5.3 Phosphorus Payment per Pound to County The permittee is required to make annual payments for phosphorus reductions to the participating county or counties in

accordance with s. 283.16(8), Wis. Stats, and the following schedule. The price per pound will be set at the time of permit

reissuance and will apply for the duration of the permit.


Annual Verification of Phosphorus Payment to County: The permittee shall make a total payment to

the participating county or counties approved by the Department by March 1 of each calendar year.

The amount due is equal to the following: (lbs of phosphorus discharged minus the permittee’s target

value) times $54.23 or $640,000, whichever is less. See the payment calculation steps in the Surface

Water section.

The permittee shall submit Form 3200-151 to the Department by March 1 of each calendar year

indicating total amount remitted to the participating counties to verify that the correct payment was

made. The first payment verification form is due by the specified Due Date.

Note: The applicable Target Value is the TMDL derived limit value as defined by s. 283.16(1)(h),

Wis. Stats. The "per pound" value is $50.00 adjusted for CPI.

03/01/2021

Annual Verification of Payment #2: Submit Form 3200-151 to the Department indicating total

amount remitted to the participating counties.

03/01/2022



03/01/2023



03/01/2024

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03/01/2025

Continued Coverage: If the permittee intends to seek a renewed variance, an application for the MDV

(Multi Discharger Variance) shall be submitted as part of the application for permit reissuance in

accordance with s. 283.16(4)(b), Wis. Stats.

Annual Verification of Payment After Permit Expiration: In the event that this permit is not reissued

prior to the expiration date, the permittee shall continue to submit Form 3200-151 to the Department

indicating total amount remitted to the participating counties by March 1 each year.


Subsection 283.16(6)(b), Wis. Stats., requires permittees that have received approval for the multi-discharger variance

(MDV) to implement a watershed project that is designed to reduce non-point sources of phosphorus within the HUC 8

watershed in which the permittee is located. The permittee has selected the “Payment to Counties” watershed option

described in s. 283.16(8), Wis. Stats. Under this option the permittee shall make annual payment(s) to participating

county(s) that are calculated based on the amount of phosphorus actually discharged during a calendar year in pounds per

year less the amount of phosphorus that would have been discharged had the permittee discharged phosphorus at a target

value concentration based on TMDL-derived limitations. The pounds of phosphorus discharged in excess of the target

value is multiplied by a per pound phosphorus charge that will equal $54.23 per pound. This schedule requires the

permittee to submit Form 3200-151 to the Department indicating the total amount remitted to the participating county(s).

5.4 Effluent Limitations for E. coli (Outfall 001) The permittee shall comply with surface water limitations for E. coli as specified. No later than 14 days following each

compliance date, the permittee shall notify the Department in writing of its compliance or noncompliance. If a submittal is

required, a timely submittal fulfills the notification requirement.


Status Update: The permittee shall submit information within the discharge monitoring report

(DMR) comment section documenting the steps taken in preparation for properly monitoring and

testing for E. coli including, but not limited to, selected test method and location of sampling.

11/21/2020

Operational Evaluation Report: The permittee shall prepare and submit an Operational Evaluation

Report to the Department for review and approval. The report shall include an evaluation of collected

effluent data and proposed operational improvements that will optimize efficacy of disinfection at the

treatment plant during the period prior to complying with final E. coli limitations and, to the extent

possible, enable compliance with the final E. coli limitations. The report shall include a plan and

schedule for implementation of the operational improvements. These improvements shall occur as

soon as possible, but not later than April 30, 2022. The report shall state whether the operational

improvements are expected to result in compliance with the final E. coli limitations.

The permittee shall implement the operational improvements in accordance with the approved plan

and schedule specified in the Operational Evaluation Report and in no case later than April 30, 2022

If the Operational Evaluation Report concludes that the operational improvements are expected to

result in compliance with the final E. coli limitations, the permittee shall comply with the final E. coli

limitations by April 30, 2022 and the permittee is not required to comply with subsequent milestones

identified below in this compliance schedule (‘Submit Facility Plan’, 'Final Plans and Specifications',

'Treatment Plant Upgrade to Meet Limitations', ‘Construction Upgrade Progress Report’, 'Complete

Construction', 'Achieve Compliance').

FACILITY PLAN - If the Operational Evaluation Report concludes that operational improvements

10/31/2021

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alone are not expected to result in compliance with the final E. coli limitations, the permittee shall

initiate development of a facility plan for meeting final E. coli limitations and comply with the

remaining required actions in this schedule of compliance.

If the Department disagrees with the conclusion of the report, and determines that the permittee can

achieve final E. coli limitations using the existing treatment system with only operational

improvements, the Department may reopen and modify the permit to include an implementation

schedule for achieving the final E. coli limitations sooner than April 30, 2025.

Submit Facility Plan: If the Operational Evaluation Report concluded that the permittee cannot

achieve final E. coli limitations with operational improvements alone, the permittee shall submit a

Facility Plan per s. NR 110.09, Wis. Adm. Code. The permittee may submit an abbreviated facility

plan if the Department determines that the modifications are minor.

04/30/2022

Final Plans and Specifications: The permittee shall submit final construction plans to the

Department for approval pursuant to ch. NR 108, Wis. Adm. Code, specifying treatment plant

upgrades that must be constructed to achieve compliance with final E. coli limitations and a schedule

for completing construction of the upgrades by the complete construction date specified below.

03/31/2023

Treatment Plant Upgrade to Meet Limitations: The permittee shall initiate bidding, procurement,

and/or construction of the project. The permittee shall obtain approval of the final construction plans

and schedule from the Department pursuant to s. 281.41. Stats., prior to initiating activities defined as

construction under ch. NR 108, Wis. Adm. Code. Upon approval of the final construction plans and

schedule by the Department pursuant to s. 281.41, Stats., the permittee shall construct the treatment

plant upgrades in accordance with the approved plans and specifications.

09/30/2023

Construction Upgrade Progress Report: The permittee shall submit a progress report on

construction upgrades.

09/30/2024

Complete Construction: The permittee shall complete construction of wastewater treatment system

upgrades.

03/31/2025

Achieve Compliance: The permittee shall achieve compliance with final E. coli limitations. 04/30/2025

Explanation of E. coli Schedule

A compliance schedule is included in the permit to provide time for the permittee to investigate options for meeting new

effluent E. coli water quality-based effluent limits while coming into compliance with the limits as soon as reasonably

possible.

Special Reporting Requirements None

Other Comments: None

Attachments: Substantial Compliance Determination – 5/8/19

Water Quality Based Effluent Limits, with Map(s) – 9/20/19

WQBEL Addendum E. coli – 5/1/2020

Public Notice

MDV Application – 4/2/19

MDV Checklist – 4/29/19

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MDV Conditional Approval – 5/8/19

Mercury Variance documents

Additional Attachment at Re-Public Notice:

DC study approval letter – 6/9/2020

Proposed Expiration Date: September 30, 2025

Justification Of Any Waivers From Permit Application Requirements None

Prepared By: Jennifer Jerich, Wastewater Specialist

Date: 1/30/2020

Revision date post fact check: 4/3/2020; revisions to the fecal coliform and E. coli requirements and editorial changes

made.

Revisions at re-public notice: 6/22/2020; Temperature limits and schedules removed.

Revision date post public notice & hearing:

permit fact sheet general information · 6/5/1984 · notes prop comp mercury, total recoverable...

Documents