NC0082376_Authorization to Construct_20021213

� State of North Carolina
Department of Environment g
o,
and Natural Resources ,r
Division of Water Quality
Michael F. Easley, Governor -
William G. Ross, Jr., Secretary CDE R
Alan W. Klimek, P.E., Director N N
December 13, 2002
Mr. H. Dale Crisp
City of Raleigh
P.O. Box 590
Raleigh, North Carolina 27602
Subject: Authorization to Construct
E.M. Johnson WTP
ATC No. 082376A01
Wake County
Dear Mr. Crisp:
The Division of Water Quality's NPDES Unit has reviewed the City of Raleigh' request for an
Authorization to Construct chemical feed improvements at the E.M. Johnson WTP. The proposed
improvements will provide for automatic pH adjustment in the residuals treatment system and for
dechlorination of treated effluent and of leakage from the water plant's clearwell.
The Division finds the proposed improvements and design to be satisfactory and hereby grants
authorization for construction or installation of the following:
• installation of a caustic storage and feed system for pH adjustment of gravity thickener
effluent;
installation of a sodium metabisulfite storage and feed system for dechlorination of final
effluent (at two locations) and of leakage from the WTP's clearwell; and
all related structures, equipment, piping, controls, and other appurtenances, as
described in the proposed plans and specifications.
This Authorization to Construct is issued in accordance with Part III, Paragraph A of NPDES Permit
No. NC0082376, issued June 28,1999, and modified August 24,1999, and shall be subject to
revocation unless the wastewater treatment facilities are constructed in accordance with the
conditions and limitations specified in that permit.
In the event that the facilities fail to perform satisfactorily, including the creation of nuisance
conditions, the Permittee shall take immediate corrective action, including those as may be required
by this Division, such as the construction of additional or replacement wastewater treatment or
disposal facilities.
Notification Requirements
The Permittee shall notify the Raleigh Regional Office, telephone number [phone], at least
forty-eight (48) hours in advance of operation of the installed facilities, so that an in -place inspection
can be made. Such notification to the regional supervisor shall be made during the normal office
hours of 8:00 a.m. until 5:00 p.m. on Monday through Friday, excluding State Holidays.
1617 Mail Service Center, Raleigh, North Carolina 27699-1617 Telephone [phone] FAX [phone]
An Equal Opportunity Affirmative Action Employer On the Internet at http://h2o.enr.state.nc.us/NPDES

ATC No. 082376A01
E.M. Johnson WTP
Engineering Certification
Upon completion of construction and prior to operation of the modified facility, the Permittee shall
provide the Division with a certification from a professional engineer registered in North Carolina
certifying that the permitted facility has been installed in accordance with the NPDES Permit, this
Authorization to Construct, and the approved plans and specifications. The certification should be
mailed to the NPDES Unit,1617 Mail Service Center, Raleigh, North Carolina 27699-1617.
ORC Requirements
The Permittee must continue to employ a certified wastewater treatment plant operator in
responsible charge (ORC) of the wastewater treatment facilities. The operator must hold a certificate
of the type and grade at least equivalent to or greater than the classification assigned to the
wastewater treatment facilities by the Certification Commission. The Permittee must also employ a
certified back-up operator of the appropriate type and grade to comply with the conditions of Title
15A, Chapter 8G, .0200. The ORC of the facility must visit each Class I facility at least weekly and
each Class H, III, and IV facility at least daily, excluding weekends and holidays; and must properly
manage and document daily operation and maintenance of the facility and comply with all other
conditions of Title 15A, Chapter 8G, .0200.
Additional Conditions
The Operational Agreement between the Permittee and the Environmental Management
Commission is incorporated herein by reference and is a condition of this Permit. Noncompliance
with the terms of the Operational Agreement shall subject the Permittee to all sanctions provided by
G. S.143-215.6 for violation of or failure to act in accordance with the terms and conditions of this
Permit.
Failure to abide by the requirements contained in this Authorization to Construct may subject the
Permittee to an enforcement action by the Division of Water Quality in accordance with North
Carolina General Statute 143-215.6A to 143-215.6C.
The issuance of this Authorization to Construct does not relieve the Permittee from its responsibility
to comply with any and all statutes, rules, regulations, or ordinances that may be imposed by other
government agencies (local, state, and federal) which have jurisdiction
The Permittee shall maintain a copy of the approved plans and specifications on file for the life of
the facility.
If you have any questions about this Authorization to Construct, please contact Mike Templeton, at
[phone], extension 541, or Randy Jones at [phone], extension 249.
Sincerely,
AN�.r Alan W. Klimek, P.E.
Director
Enclosures: Engineer's Certification Form
Copies: Mr. F. Ross Stroud (w/ enclosure) - ARCADIS
P.O. Box 31388
Raleigh, NC 27607-3366
Raleigh Regional Office, Water Quality
Technical Assistance and Certification Unit
Central Files
NPDES Unit Files

ATC SUMMARY
City of Raleigh
E.M. Johnson WTP
ATC No. 082376AOI
UT to Honeycutt Creek, Class WS-IV CA NSW
Neuse River Basin
Wake County
SCOPE
The City of Raleigh proposes to install additional chemical feed systems at residuals treatment system
at the E.M. Johnson WTP. The improvements will provide (1) pH adjustment for gravity thickener
effluent and (2) dechlorination of treated effluent and of leakage from the WT P s final product
clearwell.
RECOMMENDATIONS
1. Approve the ATC request, received October 18, 2002, and additional information
submitted December 12, 2002 .
PROTECT DESCRIPTION
The proposed improvements consist of:
• installation of a caustic storage and feed system for pH adjustment of gravity thickener
effluent;
• installation of a sodium metabisulfite storage and feed system for dechlorination of final
effluent (at two locations) and of leakage from the WTP's clearwell; and
• all related structures, equipment, piping, controls, and other appurtenances, as described in
the proposed plans and specifications.
The City is already replacing the two existing belt filter presses at the residuals treatment system with
new presses, and the current proposal is in addition to that project.
The pH control system will replace the existing manual caustic feed system with an automatic feed
system. The system includes a 10,000 gal steel storage tank with secondary containment; two variable -
speed feed pumps; and a second PVC feed line with secondary containment. A 25% caustic solution
will be fed into the gravity thickener effluent at a point downstream of the existing Parshall flume
(between the gravity thickeners and final clarifiers), and the pH meter will be located at a manhole
between the flume and the final clarifiers. The control system will be located in the existing clarifier
pump station.
The dechlorination system is being added in anticipation of Total Residual Chlorine limits in the
upcoming NPDES permit renewal. The system includes a 6,000 gal fiberglass storage tank with
secondary containment; four variable -speed feed pumps; and dual PVC feed lines, with secondary
containment, to each of three feed points. These points are (1) a manhole upstream of the final clarifiers,
(2) the clarifier effluent, and (3) in an existing manhole pump station just upstream of the stormwater
drain discharge. ORP meters will be located at each feed point, and the master control system will be
located in the existing clarifier pump station.
Drains from the storage area feed to the old sludge drying beds, which are already used from spill
containment and are normally valved off to prevent any discharge.
- 1 -

ATC Summary (cont.) City of Raleigh
• w ATC No. 082376A01 E.M. Johnson WTP
REVIEW SUMMARY
The key issues with the design package were that it did not adequately address the following.
• Metabisulfite feed rates: residual chlorine levels, metabisulfite feed concentration, and
design pumping rate.
• Mixing and contact time for each of the three metabisulfite feed points (TMStds, p.100-7: 30
sec at design peak hourly flow or at max. pump rate)
• Location of the effluent samplers with respect to the feed points. Needed to ensure
dechlor'n is adequate, once TRC limit is added to the permit.
• Placement of chemical feed lines above or below ground.
The City's consultant (ARCADIS) provided additional information to address these issues.
UNRESOLVED ISSUES
This review did not resolve issues surrounding leakage from the WTP's clearwell.
o The rate of leakage is not known, because the same pipe carries other ground and surface water
sources. But it is significant enough that, during a recent inspection, a chlorine smell was
noticeable near this storm pipe. _
o Apparently, the leak cannot be repaired easily. The City is looking at separating leakage flows
from the other waters and directing it back to the water plant or the residuals system for better
treatment. In the meantime, it will dechlorinate the flow prior to discharge.
o The storm pipe that carries and discharges the leakage is not covered under the plant's NPDES
permit. However, the storm drain discharges approx. 20 feet from Outfall 002 and can be treated
as essentially the same outfall. This should be addressed in the NPDES permit during the
upcoming renewal.
- end of summary -
-2-

SOC PRIORITY PROJECT: No
AUTHORIZATION TO CONSTRUCT
NPDES PERMIT REPORT AND RECOMMENDATIONS
FOR MODIFICATIONS TO THE CITY OF RALEIGH
E. M. JOHNSON WATER TREATMENT FACILITY
(pH adjustment using sodium hydroxide and dechlorination using sodium metabisulfite)
December 13, 2002
Project No.: 082376A01
To: Mike Templeton, Water Quality NPDES Permitting
From: Randy Jones, Raleigh Regional Office
ZOT C Z 330
County: Wake
Permit No: NCO082376
PART I - GENERAL INFORMATION
1. Facility Name and Current Address:
Mr. J. Russell Allen, City Manager
City of Raleigh
PO Boa 590
Raleigh, NC 27602
Mr. H. Dale Crisp, Public Utilities Director
City of Raleigh
PO Bog 590
Raleigh, NC 27602
City of Raleigh E. M. Johnson WTP
10301 Falls of Neuse Road
Raleigh, NC
2. Date of most recent NPDES Staff Report (attach copy): NPDES Staff Report
Dated 9/25/02 (copy attached).
3. Changes since previous action on NPDES Permit: Project is currently under
construction to replace two existing Parkson belt filter presses with two
new Ashbrook Klampress belt filter presses.
Project No.: 082376A01
Page I

4. Verify Discharge Point(s) on plans with current NPDES Permit. List for all
discharge points: The discharge points specified in the attached staff
report appear to be those also specified on the map attached to the
current permit, which expires on 2/28/02. The outfalls are identifed as
002, which appears to be the outfall identified on Drawing Number W103
of the submitted plans. The other outfall identifed in the permit is 001,
which I am told is to be a future outfall. The latitudes and longitudes are:
Outfall 002
Latitude: 35 ° 54 156 "
Outfall 001
Latitude: 35 ° 54 ' 38 "
Longitude: 78' 35' 59"
Longitude: 78' 35' 25"
Attach a USGS map extract and indicate treatment facility site and discharge
point on map: Map with attached NPDES staff report.
U.S.G.S. Quad No.: D24NE U.S.G.S. Quad Name: Wake Forest
5. Treatment plant classification (attach completed ratings sheet): Rating Sheet
attached to NPDES staff report.
PART II - DESCRIPTION OF DISCHARGE AND TREATMENT WORKS
See NPDES Staff Report
1. Existing treatment facility
a. What is the current permitted capacity of the facility?
b. Date(s) and construction activities allowed by previous
Authorizations to Construct issued in the previous two (2) years:
C. What is the actual treatment capacity of the current facility (design
volume)?
d. Please provide a description of existing or substantially constructed
wastewater treatment facilities:
Project No.: 082376A01
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2. Please provide a description of proposed wastewater treatment facilities: This
proposal includes the addition of a caustic (sodium hydroxide) storage
and feed system for pH adjustment and the addition of a sodium
metabisulfite storage and feed system for dechlorination.
The caustic feed system will be added downstream of the existing Parshall
flume, which measures flow from the gravity thickeners to the clarifiers.
The pH analyzer will consist of a measuring probe (with reference
electrodes, measuring electrodes, and a temperature compensator) and a
monitor/transmitter and will be located downstream of the Parshall flume
The pH controller. will be located in the existing clarifier pump station.
Caustic will be fed by two variable speed 12 GPH pumps to be located in
the existing thickened sludge pump station.
The 25% sodium hydroxide solution will be stored in a new 10,000 gallon
12' diameter steel tank set in a containment area and on a concrete pad.
The sodium hydroxide will be delivered in a 1" PVC chemical carrier
pipe, which will be encased in a 2" schedule 80 PVC pipe. An existing
chemical feed line will provide duality.
The sodium metabisulfite system will be constructed with three feed
points. Point 1 identified on the submitted plans is in the clarifier effluent
Parshall flume. Point 2 is in a manhole upstream of the clarifiers and
downstream of the gravity thickener Parshall flume. Point 3 is in an
existing manhole pump station just upstream of a stormwater discharge.
The chlorine sources at the facility are the filter backwash water and
groundwater that collects in a French drain around the existing clearwell.
The significance of this groundwater, which flows into a storm sewer that
is tributary to a UT to Honeycutt Creek (according to the engineer, this
storm sewer outfall is located about 20" from outfall 002), is that there is a
suspected leak of chlorinated water from this clearwell.
The sodium metabisulfite feed rate will be controlled by a controller
(oxygen reduction potential transmitter) and probe (will include
reference measuring electrodes, redox measuring electrodes, and a
temperature compensator) at each of the three feed points. A master
controller will control the three transmitters and will be located in the
existing clarifier pump station.
The sodium metabisulfite will be fed by four variable speed 12 GPH
pumps to be located in the thickened sludge pump station.
The sodium metabisulfite will be stored in a new 6,000 gallon 10'
diameter fiberglass tank set in a containment area and on a concrete pad.
Project No.: 082376A01
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The sodium metabisulfite will be delivered in a 1" PVC carrier pipe,
which will be encased in a 2" schedule 80 PVC pipe. Two parallel sodium
metabisulfite feed lines will be installed for each feed point.
3. Residuals handling and utilization/disposal scheme: See NPDES staff report
a. If residuals are being land applied, please specify DEM permit no.:
Residual Contractor:
b. Residuals stabilization:
C. Landfill:
d. Other disposal/utilization scheme (Specify):
4. Important SOC, JOC or Compliance Schedule dates: N/A
5. Wastewater Code: 21
6. MTU:510-3
7. SIC Code: 4941
III. EVALUATION AND RECOMMENDATIONS
The RRO has reviewed the submittal information for this project and discussed
various aspects of the project with Mike Templeton in NPDES Permitting and
Ross Stroud of ARCADIS. The specific details of this project are described in
II.2 of this staff report.
One of the questions that had come up during the review of this project is
regarding the stormwater discharge. The submittal indicates that there is a
possible leak from the clearwell. This leak results in chlorinated water being
discharged to a UT to Honeycutt Creek. In order to repair this leak, the facility
would likely have to be taken out of service; therefore, the City has proposed to
add dechlorination to this stormwater discharge.
Another question is the depth of the buried PVC piping in traffic areas.
According to my understanding, Ross Stroud has stated that the original project
contract (this project is a modification to the original project) requires at least
Project No.: 082376A01
Page 4

three feet of cover over the PVC piping, which complies with any DWQ
requirements.
Another question involves the dosage rates that will occur. ARCADIS sent it
calculations in support of the determinations. As Mike Templeton and I have
discussed over the telephone, there were some problems with the initial
calculations provided. Mary Sadler with ARCADIS provided revised
calculations and I spoke with her over the telephone. In the revised calcs Mary
said that she should not multiply by the solution factor, that the specific gravity
used was for that solution; however, I was thinking that the solution factor still
needed to be factored in. If so, the result is about 401 GPD of sodium
metabisulfite. In that case, the 12 GPH (288 GPD) pump will not handle the
required pumping rate. I questioned Mary about this situation and she seems
confident that the pumps are ok. In accordance with our earlier conversation,
you were going to review the calcs and possibly condition the A to C approval, as
necessary, to ensure a workable design.
Upon satisfactory review of the project by WQ NPDES Permitting and
resolution (to the satisfaction of NPDES Permitting) of the issues mentioned
above, the WQ RRO does not object to the issuance of this A to C.
2-13---e522
ture "eport,(reparer (082376A01) Date
Water Quality Regional "Supervisor (08237
file: h:\atc1082376a01
Project No.: 082376A01
Page 5
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