IA DNR - Wastewater Report
STATE OF IOWA
THOMAS J. VILSACK, GOVERNOR
SALLY J. PEDERSON, LT. GOVERNOR
DEPARTMENT OF NATURAL RESOURCES
JEFFREY R. VONK, DIRECTOR
August18,2006
CERTIFIED MAIL
.'--,
City of Dubuque
50 West 13'h SI.
Dubuque, IA 52001
ATTN: Honorabie Mayor & City Council
RE:
Dubuque Wastewater Treatment Facility Joint DNRlEPA Inspection and
Notice of Violation - 567-IAC-64.3 Permit to Operate
NPDES Permit Standard Condition #8
NPDES Permit Standard Condition #14
..'
NPDES Permit #: 3126001
Dear Honorable Mayor & City Council:
Enclosed is the report of the recent inspection of the above facility conducted by Sue Miller of the Field
Office #1 staff in conjunction with US EPA.. The US EPA will submit a separate report to the City.
We believe you will find the report self-explanatory and strongly encourage you to take action on the
requirements and/or recommendations listed at the end of the report.
After reviewing the monthly operation report for your facility, the following violation was noted for March
2006:
REPORTED VALUE
PERMITTED VALUE
Total Suspended Solids (TSS) 7-day
Avg. (Cone.)
59.57 mg/I
45mg/1
The following violations were noted for April 2006:
REPORTED VALUE
PERMITTED VALUE
TSS 7-day Average (Cone.)
TSS 7-day Avg. (Mass)
TSS 30-day Avg. (Cone.)
Fecal Coliform Maximum Daily
Total Residual Chlorine (TRC)
Maximum Daily (Cone.)
TRC Maximum Daily (Mass)
88.71 mg/I
9,332.78Ibs/day
40.1 mg/I
980 org/100 ml
1.4 mg/I
45mg/1
6,500 Ibs/day
30mg/1
200 org/100 ml
0.202 mg/I
24 Ibs/day
117.1Ibs/day
FIELD OFFICE #1 I 909 West Main Suite 4 I Manchester, IA 502057
563-927-2640 I FAX 563-927-2075
: ",
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City of Dubuque Wastewater Notice of Violation
July 26, 2006
Page 2 of 2
The following violation was noted for June 2006:
Fecal Coliform
REPORTED VALUE
480 org/100 ml
PERMITTED VALUE
200 org/100 ml
The following violation was noted for July 2006:
TSS 7-day Average (Cone.)
TSS 30-day Avg. (Cone.)
Fecal Coliform
REPORTED VALUE
68.42 mgll
37.93 mgll
100,000 org/100 ml
PERMITTED VALUE
45mg/l
30mg/l
200 org/100 ml
The City has not notified the department of the permit limit exceedances occurred. This is a violation of
NPDES permit #3126001 Standard Condition #14(c), which states "Any violation of a maximum dally
discharge limit for any of the pollutants listed by the Director in the permit to be reported within 24 hours.
The report finds that all un its are not in operation at the wastewater treatment plant. As a result the
treatment plant is organically overloaded. The third aeration basin must be brought back into service
immediately. The two clarifiers must be put back into service as soon as possible. Failure to operate
enough units to handle the amount of solids in the plant is a violation of standard permit condition #8 .
Within 120 days, the City must submit an engineering evaluation to this office that addresses the
repeated violations of total suspended solids effluent limitations. The engineering report must address
the existing design flows and the facilities ability to effectively remove solids during wet weather.
If you have any questions about the inspection or report, please contact Sue Miller or myself at this office.
Sincerely, /
/YJ l~ l ^v ",^",,-
Mike Wade
Environmental Specialist
cc: IDNR Wastewater Construction Permits Sec. (w/encl.)
Michael Van Milligan, City Manager, City Hall, 50 W. 13th St., Dubuque, IA 52001 (w/encl.)
Jonathon Brown, WPCF, 795 Julien Dubuque Dr., Dubuque, IA 52003
File: WW/Dubuque
eFile: 31 WW Dubuque 072406 nins sjm
.
NT OF NATURAL RE
ENT FACILITY I
NPoes Permlt#: 3126001
FACILITY
RESPONSIBLE
OPERATOR
DESIGN
CAPACITY
NOW
TREATING
RECEIVING
STREAM
GENERAL
DESCRIPTION:
INSPECTION
PERSONS
INTERVIEWED
SELF-
MONITORING
EFFLUENT
LIMITATIONS
SAMPLES THIS
INSPECTION
COMPLIANCE
SCHEDULE
INSPECTOR:
REVIEWER:
FACILITY INFORMATION
PLANT GRADE:
IV
NAME:
Cit of Dubu ue Water Pollution Control
RESPONSIBLE AUTHORITY/OWNER:
Cit of Dubu ue
ADDRESS:
50 West 13th St.
NAME:
Jonathon Brown
STATE:
Iowa
ZIP: PHONE:
52001 563/589-4110
CERTIFICATION NUMBER:
1671
CITY:
Dubu ue
GRADE:
IV
AVERAGE MGD:
17.32
AVERAGE MGD:
8.28 (2006)
MAXIMUM MGD:
23.24
MAXIMUM MGD
13.67 (May 2006)
POPULATION SERVED:
52,895
POUNDS BODIDAY:
24400
POUNDS CBODIDAY:
18225 (June 2006)
PE (BOD):
146108
PE (BOD):
109132 (June
2006
NPl:Ie~:l!!eRM'1!'.~oMpl:ii~J\1j(;e'.~Ii:IMMARY
Operation Reports Submitted: Required Data on Reports:
D Sat. D Mar .* D Unsat.* D Sat. D Mar .* D Unsat.*
SELF-MONITORING RESULTS:
D Satisfactor D Mar inal* [:gJ Unsatisfactor
TYPE:
None b ON R.
RESULTS:
D Satisfacto D Mar inal* D Unsatisfactor *
VISUAL APPEARANCE OF EFFLUENT:
Effluent contained solids.
Testing Adequacy:
D Sat. D Mar .* D Unsat.*
LAB DATA ATTACHED?
DYes [:gJ No
* Explain in Comments and Recommendations Section
DATE DUE:
VISUAL APPEARANCE OF RECIEIVING STREAM:
Solids plume extended at least 50 yards
downstream and solids were washing up on to the
river bank.
NEXT ITEM DUE:
COMPLIANCE WITH SCHEDULE:
D Sat. D Mar .* D Unsat.*
NAM.E Ej3: u~ Miller;.En~i~~nmental Specialist
~L<-. /:c.eUc..
NAME: Mike Wade, Efvironmental Specialist:
J, J e-tA~
DATE:
,p1/,r/C0
,
DATE:
~-JO-d
PERIOD REVIEWED:
5/01/2002 -7/1/2006
Mississippi River- A 1, B(WW)
Pure 02 Activated sludge treatment plant
DATE THIS INSPECTION:
07/25/2006
NAME:
Jonathon Brown
John Klostermann
DATE LAST INSPECTION:
OS/20/2002
TITLE:
Wastewater Plant Manager
Public Works Director
.
City Qf DubuClue WQ$t
NPDE$.Permi! #:
. .................n.'..".........
NPDES PERMIT COMPLIANCE:
The monthly operation reports (MORs) were reviewed for the reporting period from May 2002 through July
2006.
Design CapacitylEffluent Limitations - During the above mentioned reporting period the following
observations were made:
. The design influent flow rates are 17.32 MGD AWW and 23.24 MGD MWW. During the above mentioned
reporting period the facility was in compliance with the facility design flow, except for June 2002 when the
MWW was exceeded following a 5" rain.
. The 30-day and 7-day average CBODs effluent limitations are 25 mg/L and 40 mg/L respectively. The 30-
day limitation was not exceeded during the reporting period, while the 7-day limitation was exceeded during
five (5) months.
. The 30-day and 7-day average total suspended solids (T88) effluent limitations are 30 mg/L and 45 mg/L
respectively. The 30-day limitation was exceeded during ten (10) months during the reporting period, while
the 7-day limitation was exceeded during fifteen (15) months of the review period. Both the 30-day and 7-
day averages were exceeded in July 2006.
. The daily maximum fecal coliform effluent limitation is 200 organisms/1 00 ml. The daily maximum effluent
limitation was exceeded seven (7) months during the reporting period. The daily maximum was exceeded
on three occasions in July 2006; the highest exceedance was 100,000 org/100 ml. That exceedance
occurred on July 26, 2006 the day of this inspection.
. The 30-day and daily maximum total residual chlorine (TRC) effluent limitations are 0.151 mg/L and 0.202
mg/L respectively. The 30-day average was not exceeded during the reporting period, while the daily
maximum effluent limitation was exceeding in four (4) months during the reporting period.
Previous Enforcement Acton - A Notice of Violations (NOV) was issued to the City of Dubuque on
December 16, 2005 for effluent violations for 2002, 2003, 2004 and 2005. A copy of the NOV is attached to
this report.
FACILITY EVALUATION:
PRE-TREATMENT UNITS (This Facility)
Raw influent is delivered to the City of Dubuque WWTF via two separate forcemains and enters the facility
through bar screens followed by two grit basins. The grit slurry is then normally transported to two grit
removal units, however one unit was down on the day of this inspection. A pump was on order.
For your information, the rule governing landfilling of grit and screenings from wastewater plants is: lAC
Subrule 109.11 (3) Stabilized grit, bar screenings, and grease skimmings. The sanitary landfill operator, the
generator, and the hauler shall comply with the following conditions and requirements whenever stabilized
grit, bar screenings, or grease skimmings are disposed of in a sanitary landfill.
a. The waste cannot contain any free liquids as determined by the paint filter liquids test.
b. The generator shall stabilize the grit, bar screenings, and grease skimmings prior to their
disposal at the landfill in order to destroy any pathogenic organisms. Stabilization can be done
by addition of lime to raise the pH to at least 12 for two hours.
c. The generator shall prearrange a delivery schedule with the landfill operator.
d. Upon arrival at the landfill, the hauler shall identify the waste to the landfill attendant.
e. The landfill operator shall direct the hauler to the working face.
f. The waste shall be deposited at the working face, covered with regular refuse or soil and
compacted.
TREATMENT UNITS
Primary treatment is provided by three, covered primary clarifiers. At the time of this inspection only two
primary clarifiers are on line.
Secondary treatment is provided in three, pure oxygen activated sludge basins. Only two basins were
being operated and the third basin was operating as a standby basin. The basins are covered and nine (9)
mechanical mixers located on top of each basin. Oxygen is controlled by sensors located in the
headspace. Dissolved oxygen levels reported on the monthly operating reports (MORs) for 2006 range
from a high of 16.2 to a low of 0.5 mg/I, but average approximately 7-9 mg/1. It's not clear why the DO
levels are so variable. The operator should have the sensors checked in accordance with the
manufacturer's specifications.
Four final clarifiers normally provide final settling; however one clarifier was down for maintenance at the
time of this inspection.
Disinfection is provided by the addition of liquid chlorine prior to a chlorine contact chamber. The effluent is
dechlorinated with sodium bisulfite prior to discharge.
SLUDGE HANDLING AND DISPOSAL
This facility does not have a sludge digester. Primary sludge and secondary sludge are stored separately
and blended at a 55/45 primary to secondary ratio before dewatering via centrifuge. The sludge is
dewatered to 28% solids before feeding to the fluidized bed incinerator. Final disposal is in the on-site ash
ponds. The facility is investigating other alternative disposal methods for the ash. Mr. Brown reported that
the facility has trouble maintaining the optimal sludge blending rate. The facility has two fluidized bed
incinerators, but only one is used. The incinerator is only operated Monday through Friday.
The City is in the process of hiring an engineering company to perform a "solids study." This is an area
that can cause bottlenecks in the system.
FLOW MEASUREMENT
Magnetic meters on the two influent forcemains are the only flow measurement at the plant. An effluent
pressure transducer no longer functions. The mag meters must be calibrated to ensure accurate flow
readings are being reported.
PUMPING
One intermediary pump station is located between the old 200' diameter, trickling filters and the activated
sludge basins. These pumps serve to pump excess rainwater out of the uncovered, unused trickling
filters. The City should find an alternative to treating this extraneous water. Just one inch of water in
these tanks adds approximately 113,000 gallons of water to the facility. That is almost 7% of the average
wet weather flow to the plant. This water is not being accounted for in the plant flow data.
EMERGENCY POWER
Mr. Brown reported that the wastewater treatment plant is served by two separate power sources. Several
of the lift stations have no back up power source. The City maintains two portable generators that can be
used at the four lift stations that have connections for them. When the Cedar, Dog Track and Terminal lift
stations are renovated, they will be equipped with on-site emergency generators. The City has several
portable pumps for emergency pumping in the case of pump outages at the other lift stations.
City of Dubuque Wa
NPDES Permit #:
OBSERVATIONS:
On the night prior to this inspection, the area received approximately 2.3 " of precipitation in the previous
12 hours. The sludge blanket was observed to rise over the baffles in all three of the final clarifiers and
sludge was being released to the receiving stream. See attached photos. Mr. Brown reported that this
occurs when the area receives heavy rains. This is an "upset condition" as defined in Standard Condition
#14 of the facility NPDES permit. When TSS effluent values exceeds permit effluent limitations, the City
"shall" notify the department within 24 hours.
A review of monthly operating reports revealed that total suspended solids in the discharge have at times
exceeded the amount in the influent wastewater. Actions were not taken to increase plant capacity.
Standard condition #8 requires that "all facilities and control systems shall be operated as efficiently as
possible and maintained in working order." Failure to operate enough units to handle the amount of solids
in the plant is a violation of this permit condition.
When solids leave the plant, the effectiveness of disinfection is reduced. When the amount of solids
reaches the level that occurred on July 26, 2006, disinfection was ineffective resulting in a fecal count that
was 500 times the permit effluent limitation, potentially exposing untold numbers of anglers and boaters to
human pathogens. Again Standard Condition #14 requires you to notify the department whenever a
maximum daily discharge limit for any pOllutant listed in the permit has been exceeded.
Sludge handling appears to be a bottleneck at the Dubuque plant. The operator must reduce the amount
of sludge storage in the treatment units. The solids study that Mr. Brown talked about should address this
problem. Flow equalization could also provide a buffer for the plant during wet weather.
PRIOR ENFORCEMENT ACTIONS:
The Dubuque Water Pollution Control Facility has had a history of solids violations that can be traced the
beginning of its operations as an activated sludge plant. In 1993 Administrative Consent Order (ACO) was
issued that required the City to upgrade the wastewater treatment facility and the sludge handling facilities
in order to meet final effluent limitations to total suspended solids. In response to the ACO, the City
removed the Zimpro sludge heat treatment unit; added a polymer and ferric chloride system to the splitter
box before the aeration basins; replaced sludge pumps; installed a SCADA control system; discontinued
oxygen generation and converted to purchased oxygen; and eliminated hydraulic bottlenecks in the
system.
CONCLUSIONS:
TSS violations have continued even after the upgrades. Fifteen violations in the past 4 years were
reported; three in the past six months. Excess solids in the effluent decrease the effectiveness of
disinfection resulting in several fecal coliform violations. The facility appears to adequately handle solids
during dry weather, however the plant is easily upset during wet weather. The plant is currently operating
at less than full capacity. One primary clarifier, one aeration basin and one final clarifier are currently not in
operation. The final clarifier is down for maintenance and will be returned to service. The other units are
not normally used.
The plant's design load is based on all units being in operation. With the three units out of service, the
plant can only handle 70% of its design loads and flows, i.e. flows of 12.124 AWW, 16.27 MWW; and an
organic load of 17,080 pounds of BOD per day. Considering the reduction in capacity by having the units
out of service, the plant is organically overloaded. The third aeration basin must be immediately placed
back in service. The two clarifiers must be put back into service as soon as possible.
CONCLUSIONS (Cont'd)
The City should consider flow equalization to buffer the plant in times of heavy precipitation. The plant
design flows appear to exceed levels that the plant can effectively treat. The City must have an engineering
evaluation performed to address the continuing problem of TSS effluent violations. The engineering report
must address the existing design flows and the facilities ability to effectively remove solids during wet
weather.
The City must notify the department whenever the conditions outlined in Standard Condition #14 occur.
SUMMARY OF REQUIRMENTS
1. The third aeration basin must be immediately placed back in service. The two clarifiers must be
put back into service as soon as possible.
2. The City must notify the department of any upset conditions and any violations of a maximum daily
discharge permit limit within 24 hours of occurrence.
3. When TSS effluent values exceed the 7-day average, the operator must collect a fecal coliform sample
and report the values to the field office within 24 hours. The field office will determine if public
notification will be required.
4. The influent flowmeters must be calibrated.
5. Within 120 davs, the City must submit an engineering evaluation to this office that addresses the
repeated violations of total suspended solids effluent limitations. The engineering report must address
the existing design flows and the facilities ability to effectively remove solids during wet weather. This
plan must include a timetable for implementing any modification to this plant. This timetable, if
acceptable to this department, will be included in the operation permit for this facility.
6. All water pumped into the facility from the abandoned trickling filters must be included in the influent
flow data submitted to this department.
7. The City must notify the department whenever the conditions outlined in Standard Condition #14 occur.
SUMMARY OF RECOMMENDATIONS
1. The City should consider flow equalization to buffer the plant in times of heavy precipitation.
2. The City should consider repairing the effluent flowmeter to have a backup and also to use to check the
accuracy of the influent flowmeter.
3. The City should find an alternative to treating the extraneous rain water that collects in the abandoned
trickling filters.
567-64.3(4558) Permit to operate.
64.3(1) Except as provided otherwise in this subrule and in 567-Chapter 65, no person
shall operate any wastewater disposal system or part thereof without, or contrary to any
condition of, an operation permit issued by the director; nor shall the permittee of a
system to which a sewer extension has been made under a construction permit limited
pursuant to 64.2(10), paragraph "a," "b"or "f,"allows a connection to such sewer
extension in violation of any special limitation in such construction permit.
Standard Condition 8. PROPER OPERATION AND MAINTENANCE
All facilities and control systems shall be operated as efficiently as possible and
maintained in good working order. A sufficient number of staff, adequately trained and
knowledgeable in the operation of your facility shall be retained at all times and
adequate laboratory controls and appropriate quality assurance procedures shall be
provided to maintain compliance with the conditions of this permit.
{See 40 CFR 122.41(e) and 567 64.7(5)(f) lAC}
Standard Condition 14. TWENTY-FOUR HOUR REPORTING
You shall report any noncompliance that may endanger human health or the
environment. Information shall be provided orally within 24 hours from the time you
become aware of the circumstances. A written submission that includes a description of
noncompliance and its cause; the period of noncompliance including exact dates and
times, whether the noncompliance has been corrected or the anticipated time it is
expected to continue; and the steps taken or planned to reduce, eliminate, and prevent a
reoccurrence of the noncompliance must be provided within 5 days of the occurrence.
The following instances of noncompliance must be reported within 24 hours of
occurrence:
(a) Any unanticipated bypass which exceeds any effluent limitation in the permit.
{See 40 CFR 122.41 (1)(5)(ii)(A)}
(b) Any upset which exceeds any effluent limitation in the permit.
{See 40 CFR 122.41 (1)(5)(ii)(B)}
(c) Any violation of a maximum daily discharge limit for any of the pollutants listed by
the Director in the permit to be reported within 24 hours.
{See 40 CFR 122.41 (I)(5)(ii)(C)}
~ , ....
The two forcemains through which aU wastewater is delivered to the plant. Left is the Terminal forcemain.
The right one is the Catfish Creek forcemain.
One of two mechanically cleaned, bar screens in the headworks building.
. ,>. ....
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The two forcemains through which all wastewater is delivered to the plant. Left is the T errninal foreamain.
The right one is the Catfish Creek foreamain.
One of two mechanically cleaned. bar screens in the headworks building.
Dewatered bar screenings are dropped through a hatch to an awaiting dumpster below.
Secondary sludge storage.
. ,
Grit mixing basin.
Inside a primary darifier.
Primary sludge storage.
One of two abandoned trickling filters.
. .
This pump station is dedicated to pumping collected water from the abandoned trickling filters.
Pure oxygen storage tanks.
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Portable generators.
Standing on top of the aeration basins. Mechanical mixers are mounted on the roof.
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Solids going over the weir in a final clarifier.
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Rising sludge blanket in a final clarifier.
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The following photos courtesy of EPA.
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Photo 1: IMG 2518: Looking east along outfall pipe into Mississippi River. Note the lack of sludge and foam at the
bottom of the photo, upstream of discharge.
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Photo 2: IMG 2519: Same location as IMG 2518, looking downstream or south along the shore. Note
the light colored foam along the shoreline for about 0.5 miles.
Photo 3: IMG 2520: Same location as 2519, clos&-up along pipe. Note the foam In the center of the
photograph. Note the light brown colored sediment within the water.
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Photo 4: IMG 2521: Same location as 2519, looking downstream into the water. Note the light colored
sediment under the water surface next to the foam at the water surface. Both of these Indicated sludge
discharge to the river.
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STATE OF IOWA
THOMAS J. VI LSACK, GOVERNOR
SALLY J. PEDERSON, LT. GOVERNOR
DEPARTMENT OF NATURAL RESOURCES
JEFFREY R. VONK, DIRECTOR
CERTIFIED MAIL
700511/;OOtJO<! 'If/LiP L/d-.dS"
December 16,2005
City of Dubuque
50 W 13th SI.
Dubuque, IA 52001
ATTENTION: Mayor and City Council
RE: NOTICE OF VIOLATION of NPDES Permit Limits
NPDES Permit No. 5307001
After reviewing the monthly operation reports for your wastewater facility, several effluent
violations were noted since January 1, 2002. Please refer to your facility NPDES permit for
permit limits.
The following permit violations were noted for fecal coliform in 2005:
REPORTED VALUE
September
October
2,200 organisms/1 OOml
410 organisms/1 OOml
The following violations were noted for fecal coliform in 2004:
REPORTED VALUE
October
3000 organisms/100ml
The following violations were noted for fecal coliform in 2003:
REPORTED VALUE
~ ~ ~ ~ rEfR)
DEe I 6 1IlOO ~
June
240 organisms/1 OOml
DNR F.O.1
Field Office 1, 909 West Main Suite 4, Manchester, iA 52057
5631927-2640 FAX 563/927-2075
:
Dubuque WWTF NOV
December 16, 2005
Page 2 of 4
The following violations were noted for Total Suspended Solids (TSS) in 2005:
REPORTED VALUE REPORTED VALUE REPORTED VALUE
7- Day Avq. 30-Day Avq. 7- Day Avq.
Concentration Concentration Mass
February 134 mg/I 56 mg/I 9925 #/day
September 153 mg/I 47 mg/I 11790 #/day
October 75 mg/I 37 mg/I NA
November 242 mg/I 67 mg/I 14951 #/day
The following violations were noted for Total Suspended Solids (TSS) in 2004:
REPORTED VALUE REPORTED VALUE REPORTED VALUE
7- Day Avq. 30-Day Avq. 7- Day Avq.
Concentration Concentration Mass
March 97 mg/I 40 mg/I 9741 #/day
December 93 mg/I 36 mg/I NA
The following concentration violations were noted for Total Suspended Solids (TSS) in 2003:
REPORTED VALUE REPORTED VALUE REPORTED VALUE
7- Day Avq. 30-Day Avq. 7- Day Avq.
Concentration Concentration Mass
April 77 mg/I 44 mg/I NA
May 47 mg/I NA NA
September 70 mg/I NA NA
November 55 mg/I NA 8220 #/day
The following concentration violations were noted for Total Suspended Solids (TSS) in 2002:
REPORTED VALUE REPORTED VALUE REPORTED VALUE
7- Day Avq. 30-Day Avq. 7- Day Avq.
Concentration Concentration Mass
January 132 mg/I 44 mg/I 7320 #/day
June 126 mg/I 35 mg/I NA
August 88 mg/I NA 9903 #/day
Dubuque WWTF NOV
December 16, 2005
Page 3 of 4
The following concentration violations were noted for 5-Day Carbonaceous Biological Oxygen
Demand (CBODs) for 2005:
February
September
November
REPORTED VALUE
7- Day Avq.
Concentration
44 mg/I
45 mg/I
82 mg/I
REPORTED VALUE
30- Day Avq.
Concentration
NA
NA
26 mg/I
The following concentration violations were noted for CBODs for 2003:
September
REPORTED VALUE
7- Day Avq.
Concentration
61 mg/I
The following concentration violations were noted for CBODs for 2002:
June
REPORTED VALUE
7- Day Avq.
Concentration
49 mg/I
The following concentration violations were noted for Total Residual Chlorine (TRC) for 2005:
April
REPORTED VALUE
Daily Maximum
Concentration
0.45 mg/I
REPORTED VALUE
Daily Maximum
Mass
28 #/day
The following concentration violations were noted for TRC for 2004:
May
June
REPORTED VALUE
Daily Maximum
Concentration
0.48 mg/I
0.48 mg/I
REPORTED VALUE
Daily Maximum
Mass
46 #/day
28.01 #/day
The following concentration violations were noted for TRC for 2003:
July
REPORTED VALUE
Daily Maximum
Concentration
0.39 mg/I
REPORTED VALUE
Daily Maximum
Mass
29 #/day
Dubuque WWTF NOV
December 16, 2005
Page 4 of 4
The following concentration violations were noted for TRC for 2002:
June
REPORTED VALUE
Dailv Maximum
Mass
32 #/day
In addition to the above listed violations, annual effluent toxicity tests results were not
conducted for the 12-month period ending December 31, 2004.
It has also been brought to our attention that the City has not submitted the total dissolved
solids (TDS) and chloride tests required by our permitting section to complete the renewal of the
NPDES permit for the Dubuque wastewater plant. Please submit these test results as soon as
possible to Courtney Cswercko, DNR Wastewater Section, 502 E. 9th St., Des Moines, IA
50319-0034.
Within 90 days, the City must submit a Plan of Action that includes a schedule for facility repair,
replacement, or rehabilitation needed in order to meet the facility permit limits for fecal bacteria,
total suspended solids, CBOD5, and total residual chlorine. In the meantime, the City must begin
a program of 5 fecal bacteria samples collected each month sampling during the disinfecting
season until consistent compliance with fecal coliform permit limits can be demonstrated. The
fecal limit of 200 org/1 00 ml will be based on a geometric mean of the 5 samples, not a 30-day
average. Whenever the facility is out of compliance with the effluent fecal coliform limit, the City
must notify this office immediately.
This notice does not preclude the DNR from pursuing additional enforcement action regarding
these or any other violations.
Sincerely,
ENVIRONMENTAL SERVICES DIVISION
j)I) Jv G'Jo-vt~
Mike Wade
Environmental Specialist Senior
c: Courtney Cswercko, DNR - Wastewater Section - Des Moines
Jon Brown, Wastewater Superintendent, City of Dubuque
Michael Van Milligan, City Manager, City of Dubuque
File: WW/Dubuque
eFile: 31 WW Dubuque 101605 nltr sjm
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lAC 12/3/86, 11/19/97 Environmental Protection[567] Ch 64, p.25
RAINFALL INTENSITY - DURATION - FREQUENCY CURVES
Appendix A
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