WQCS00383_More Information Requested_20180716

Water Resources
Environmental Quality
July 12, 2018
The Honorable Eulis Willis, Mayor
Town of Navassa
334 Main Street
Navassa, NC 28451
Subject: Permit No. WQCS00383
Town of Navassa
Navassa Collection System
Brunswick County
Dear Mayor Willis:
ROY COOPER
Governor
MICHAEL S. REGAN
Secrelco y
LIN )A CULPEPPER
Interim Direclor
Thank you for your response received by the Division on June 28, 2018. In your response you dispute
the average sewer flow rates provided by Brunswick County and request an extension on submitting the
application for an individual collection system permit. Please respond to comments 1 and 2 by August
13, 2018.
1. Provide documentation that the metered average sewer flow rates provided by Brunswick
County are not indicative of the Town's collection system flow rates (e.g. map showing sewer
line connections and metering sites or other appropriate documentation).
2. Provide a timetable for the installation of the "bypass system".
As you are aware, 15A NCAC 02T .0403 applies to all collection systems. Please submit the following
items as indicated below.
3. A map of the sewer system. (November 2, 2018)
4. An operation and maintenance plan that includes pump station inspection frequency,
preventative maintenance schedule, spare parts inventory and a response plan to address
sanitary sewer overflows. (August 13, 2018)
Please be aware that daily inspections are required at pump stations not connected to a remote
alarm system (telemetry or SCADA).
5. Logs or forms to document inspections of pump stations and high priority line and the annual
general observation of the collection system. (see web site) (August 131 2018)
6. Documentation of legal authority to require grease interceptors, along with legal means to
inspect grease interceptors, enforce for violations and control grease entering from other
systems. (example ordinances attached) (November 2, 2018)
7. Documentation of the bkannual distribution of grease educational materials. (December 3,
2018)
State of North Carolina � Environmental Quality
1617 Mail Service Center � Raleigh, North Carolina 27699-1617
919-707-9000

Submit these items to my attention at: 1617 Mail Service Center, Raleigh, NC 27699-1617.
More information regarding the collection system program and operational / record keeping logs (scroll
down to Resources) are available at our web site:
https://deg.nc.gov/about/divisions/water-resources/water-resources-permits/wastewater
branch/collection-systems/system-wide-collection-system-permitting
If you have any questions or concerns please contact me at [phone] or via email
([e-mail]) or Dean Hunkele of the Wilmington Regional Office at [phone] or
via email ([e-mail]).
Sincerely,
�.
Deborah Gore
PERCS Supervisor
Cc: Wilmington Regional Office
Central Files
PERCS

CITY OF CLAREMONT
PRESS RELEASE
FOR IMMEDATE RELEASE
October 20, 2011
The City of Claremont will hold a public hearing to discuss changes to the Claremont
Code of Ordinances in reference to the adoption of a Fats, Oils and Grease Program.
The public is encouraged to attend this meeting and give input new section of the
sewer use ordinance. The hearing will be held during the regularly scheduled City of
Claremont Council meeting on November 7, 2011 at 7*00 pm in the Training Room
at the Claremont Police Department. For more information please contact
Claremont City Hall at 828-459-7009
MEDIA CONTACT:
Doug Barrick
City Manager
CITY OF CLAREMONT
P.O. BOX 446, CLAREMONT, NC 28610

CITY OF CLAREMONT
PUBLIC UTILITIES DEPARTMENT
FAT5, OILS, AND GREASE CONTROL ORDINANCE

FATS, OILS &GREASE (FOG) ORDINANCE INTRODUCTION
Sewer Maintenance on Main Wastewater ]Lines
The City's primary responsibility for the sewer system is to maintain unobstructed wastewater
flow in the collection system. To accomplish this, the City routinely cleans sewer lines and
perfo ms preventive maintenance and repairs. If you experience a sewer system backup or
observe a clean out or sewer manhole overflowing, please notify the City of Claremont as soon
as possible by contacting 828459-7009.
Sewer Stoppages
When a stoppage occurs, contact the City of Claremont at 828-459-7009, Mon -Fri 8 AM - SPM.
The City will assess the stoppage to determine if the blockage is on the City's side of the sewer
line or the homeowner's side of the sewer line. The City of Claremont will clear blockages that
occur in the main sewer line or in the sewer lateral, from the main line to the clean out pipe at the
edge of the property. The sewer clean out is a vertical, capped, 4" pipe that provides direct access
to the sewer system. Homeowners are responsible for blockages that occur in the sewer lateral,
located between the clean out pipe and the dwelling. If there is no clean out pipe at the edge of
the property, the homeowner is responsible for blockages that occur anywhere in the sewer
lateral. aj j
Fats, Oils and Grease Control
Fats, Oils, and Grease (FOG) are problem substances in wastewater that can be controlled by
properly installed and maintained interceptors. FOGS are the leading cause of sanitary sewer
overflows in North Carolina. These overflows disrupt residential, commercial and industrial
operations and carry the potential for health risks. The City by nature of this ordinance now
requires that all food service establishments install and maintain a properly sized grease and oil
interceptor
Any user of the sanitary sewer collection and treatment system is subject to the City of
Claremont's Sanitary Sewer Use Ordinance. Institutional and commercial food preparation and
serving facilities are required to adequately intercept and retain fats, oils and greases prior to
disebarge into the sanitary sewer collection and treatment system. In certain cases, an Industrial
Discharge Permit will be required of a user in order to comply with the Sanitary Sewer Use
Ordinance.
Residential users are asked to consider their own cleaning practices and their impact on the
control of greasy wash water, food solids and oils to the City of Claremont's sanitary sewer
system. Please contact the City of Claremont at 828-459-7009 for additional information and a
copy of best management practice.
2

FATS, OILS AND GREASE CONTRUE ORDINANCE
In an effort to avoid sewer overflows caused by Fats, Oils and Grease (FOG) blockages in the
City's wastewater collection system that lead to public health concerns and environmental
degradation, the City of Claremont is required by the NC Division of Water Quality to develop,
implement and administer a FOG Control Program.
The overall goal of the Program is to form a collaborative relationship between the City of
Claremont's Public Works Department staff and local commercial and institutional food service
establishments (FSEs) to ensure protection of the sewer system, public health and local water
quality through implementation of appropriate and appropriately -sized FOG control devices. The
City's FOG Program will be evaluated periodically and may be modified as necessary to
maximize the effectiveness of the FOG Program,
Existing Food Service Establishments
If required by the City, existing food service establishments (FSEs) shall install an appropriately -
sized grease interceptor within 180 days after written notification. Factors to be taken into
consideration for interceptor sizing include volume of wastewater discharge, types of cooking
appliances, number and size of dishwashing facilities, types of foods being prepared, number of
dining room seats, hours of operation and business location. FSEs with existing grease
interceptors will not be required to install new devices unless the City deems the existing
interceptor to be inadequately -sized di in uffciept i
i
New Food Service Establishments
All new FSEs (after the effective date of this FOG Program) shall be required to install an
external grease interceptor of appropriate size. No FSEs shall begin operations until the grease
interceptor is approved and inspected by the City. Factors to be taken into consideration for
interceptor sizing include volume of wastewater discharge, types of cooking appliances, number
and size of dishwashing facilities, types of foods being prepared, number of dining room seats,
hours of operation and business location.
Grease Interceptor Sizing Criteria
Grease interceptors shall be designed to provide a minimum of 24 minutes of hydraulic retention
time at peak wastewater flow from the facility. The peak wastewater flow shall be calculated
using the Manning Formula which takes into account depth of flow in the pipe, slope of pipe,
pipe diameter and pipe roughness. The Manning's equation to calculate the wastewater flowrate
for a pipe flowing frill under a non -pressurized condition is:
3

where:
Oult = fidl channel wastewater flowrate, cfs
s = pipe slope, ftft
n —pipe roughness coefficient, unitless = 0.012
D —pipe diameter, inches
The adjusted wastewater flowrate for a pipe flowing pa1•tially filll shall be calculated based upon
the flow depth ratio in the pipe using:
ti-where:
QQ,t; =adjusted wastewater flowrate, cfs
Qj,,tt = fitll channel wastewater flowrate, cfs
Q/Qf,tt —flow ratio based on depth ratio in pipe, unitless
To calculate the minimum grease interceptor volume with 24 minutes hydraulic retention, use the
following equation:
� = Qaa� x 60 sec/min_ � ?4 minutes � 7.4� gal/cu.ft.
i
yvl2et e }
V = grease interceptor volutne, gallons
Q,,ij = wastewaterflowrate, cfs
The minimum grease interceptor size that shall be acceptable is 750 gallons. The maximum
grease interceptor size shall be 1,500 gallons. If a larger volume tank is required to meet the
minimum hydraulic retention time, multiple 1,500 gallon interceptors shall be constructed and
plumbed in series.
Only in specific `hardship' cases will a FSE be permitted by the City to install an under -the -sink
or in -floor, automatic or manual, grease trap. In addition to the sizing factors described above,
additional factors to be taken into consideration by the City shall include building space
constraints, site elevation constraints, and location of the City's sewer main.
Grease Interceptor Standards of Construction
The following standards of construction are applicaUle to new extei71a1, in -ground grease
interceptors. Please refer to the drawing for reference:
1. All grease interceptor design plans shall be approved by the City prior to construction,
2. Wastewater from sanitary facilities (bathrooms, non -kitchen sinks) shall not be
introduced into any grease interceptor.
4

3. All dishwater drain lines or floor drains shall have permanently fixed screens with
maximum '/4" openings to prevent pass through of large solids into the grease interceptor.
inlet tee should be constructed to disperse influent wastewater in the first chamber to
avoid hydraulic short-circuiting and disrupting the grease separation process. The inlet
tee should extend 12-16 inches below the static water level.
e 24'CLEAA ACCESS
.�OPENINOS
X 2.6'BAFFLE
+ }yAlLTEEB
PLAN VIEW
SECTION X-X
OIL AND GREASE TRAP
DIMENSION CHART
CAP PAL)
DM'A'
WA •D'
ON RG'
DRA'0' SUU1
750
64'
4'-0'
SIT
3-111
1000
64'
C-S'
6-20
3.16
1250
64•
4'-8'
6•20
1S00
64•
6.0'
6-23
P47
NOTES
,. CONCRETE 2d DAYF`C=4500 PSI
2 REIlAt AM A-615 GRADE 60
3 MESIt ASTM A•165 GRADE 66
4. DESION:ACI 318,63 BIAt01NG CODE
ASTM C4157 MWM.NM STRUCTURAL DESIGN
LOADING FOR UNDERGIVUND PRECAST
CONCRETE UTMY STRUCTURES
5 10AD5: IF20TRUCN MEEL YAM 30%IMPACT PER AASHTO
IF IN DRIVEWAY PARIONG LOT OR OTFER TRAFFIC AREA
Q FiLL WRH CLEA14 WATER PRIOR 70 START UP OF SYSTEM
7. AIL PIPE PENEIMTO NS SKU BE WATERTWIT
4 ALTERNATE DESM hIUST BE APPROVED BY THE CITY OF CLAREMONT
GREASE INTERCEPTOR
STANDARD DETAIL
CITY OF CLAREMONT
2011
5. A baffle wall with two (2) — 6-inch baffle wall tees shall be placed approximately 2/3rds
of the length of the grease interceptor to create a 13c chamber for solids settling and grease
Rotation, and a 2nd chamber for wastewater discharge and sampling. The baffle wall shall
be connected to the bottom of the tank and allow an air gap at the top of the tank. The 2
baffle tees shall not extend greater than 30% below the static water level in the first
chamber.
6. A minimum 6-inch outlet tee should be constructed extending no greater than 50%below
the static water level. The outlet tee should allow for adip-and-grab sample to be taken
for laboratory analysis. The elevation differential between the inlet and outlet tees shall
be 2 inches.
5

7. The top slab of the grease interceptor shall have minimum 24" access openings installed
at grade to allow access to the grease interceptor's inlet tee and outlet tee. If placed in a
driveway, parking lot or other traffic area, the entire grease interceptor shall be highway
(H-20 load) rated.
8. All grease interceptor joints shall be properly sealed using mastic, butyl iubber or other
pliable sealant that is waterproof, corrosion -resistant and approved for use in septic tanks.
9. In addition to the grease interceptor, a separate `sample vault' may also be constructed
for more accurate effluent monitoring if preferred by the FSE.
10. A licensed NC Plumbing Contractor shall install the grease interceptor in compliance
with the latest edition of the Uniform Plumbing Code.
Approved internal under -the -sink or in -floor grease traps shall be sized to maximize hydraulic
retention time and grease storage. These units shall be installed by a licensed NC Plumbing
Contractor.
Operation &Maintenance Responsibilities
FSEs shall be solely responsible for operating the grease interceptor or trap within the
operational capabilities for which it was designed.
1. FSEs shall develop and imple�ept'tBest Manage�naiit Practices (BMPs) to minimize FOG
discharges. FSEs shall be res ox sib` efir - o, lingt1appropriate signage and educating its
employees in the proper disposal- of1ood wastes -and dishwashing techniques. Written
records shall be maintained by the FSE for disposal of cooking oil, grease interceptor
maintenance and any repairs. Records shall be maintained for a minimum of 2 years by
the FSE and document the date of service, name of service provider, volume of waste
removed and other pertinent information. These records shall remain on the FSE
premises and be available for inspection by the City's staff during normal business hours.
2. Should new sinks or dishwashing units be installed, or existing units replaced with new
units of different capacities, which affect the volume of wastewater being discharged to
the City's sewer system, it shall be the responsibility of the FSE to notify the City of
Claremont's Public Works Department in writing a minimum of 30 days prior to
installing such new facilities. The City of Claremont will evaluate whether the existing
grease interceptor is appropriatelysized to handle the additional flow. Operational
adjustments proposed by the FSE may also be considered by the City in lieu of increased
interceptor size.
3. When settled solids in the grease interceptor's first chamber accumulate to 20% (1/51h) of
the depth of the chamber or 60 days lapses between cleanouts, whichever occurs first, the
FSE shall be required to cleanout the chamber by contracting a pump -and -haul service.
Under -the -sink grease traps shall be cleaned out weekly, or more frequently if needed, by
the FSE.

4. No solids greater than'/z-inch shall be discharged into the grease interceptor at any time.
Grease interceptors shall be kept free from rocks, grit, gravel, sand, shells, utensils,
cigarettes, rags, etc. which may reduce the effective treatment volume of the interceptor.
5. The City may randomly schedule sampling of the wastewater exiting the grease
interceptor a minimum of one (1) time annually using a NC certified laboratory and
report the results to the FSE. The laboratory shall use USEPA Method 413.1 in analyzing
the sample for FOG. The purpose of FOG sampling shall be for data analysis to assist
with the City's scheduling of downstream maintenance. The City does not intend to
impose numerical FOG limits on the wastewater discharge from individual FSEs, unless
the City is experiencing recurring FOG problems in the collection system downstream of
the FOG -producing discharge points and determines that numerical limits should be
assigned.
Prohibitions
1. The use of hot water to `flush' the grease interceptor is strictly prohibited.
2. The use of enzymes, chemical or biological additives is not considered an acceptable
grease interceptor maintenance practice.
3. Disposal of fryer oil to the City's sewer system or storm water system is specifically
prohibited.
4. Wastes removed from the grease ffite:Gep ors shall not be discharged into the City's
sewer system or storm water system. All removed materials shall be disposed of in
accordance with Federal, State and Local statutes, policies and ordinances.
5. The practice of re -introducing wastewater pumped from grease interceptors back into an
interceptor is strictly prohibited. Interceptors must be serviced and emptied of the waste
content.
Costs Responsibility
FSEs shall be solely responsible for any and all costs related to the construction, operation,
maintenance, wastewater discharge samples taken by the City or FSE, and any adjustments or
repairs to the grease interceptors.
If any repairs are discovered by the City's staff during facility inspection, the FSE shall have 45
days from the time of first written notice by the City to make necessary operational adjustments
or repairs. It shall be the FSE's responsibility to notify the City in writing when adjustments or
repairs have been completed.
Variance
A variance may be requested by the FSE of a design and/or maintenance requirement if
sufficient documentation acid justification is submitted by the FSE in writing to the City clearly
explaining the need for a variance. The City will notify the FSE in writing of the acceptance or
7

denial of the variance request. The City reserves the right to revoke an issued variance when
deemed necessary.
A variance granted to a FSE by the City is not transferable and shall become null and void upon
transfer of building lessee or property ownership. The new lessee or property owner shall be
required to install a grease interceptor in accordance with the provisions for new FSEs or request
a new variance from the City in accordance with the procedures set forth above.
Inspections
Grease interceptors shall be inspected a minimum of once per month by the FSE. FSEs shall
allow City staff access at all reasonable times to all parts of the premises for the purpose of
inspection, sampling and records examination. The City shall retain the right to set up on the
FSE's property such devices as necessary to conduct inspection, sampling and compliance
monitoring. The City will coordinate with the FSE to minimize business disruptions.
FOG Program Enforcement
If a grease interceptor fails an inspection, the City inspector shall notify the FSE or Owner that
maintenance must be performed in the interceptor within a specified time frame but no more than
10 calendar days. The inspector shall return to re -inspect to ensure compliance. If the interceptor
Fails re -inspection, a notice of violation shall be issued and maintenance shall be performed
immediately.
i,
Any grease interceptor which receive tlire� �3) Not�c s o Violations within a 24 month period
shall be deemed a nuisance by the City Manager and shall require con-ective actions as
determined by the City Manager to cure the nuisance, including, if deemed necessary termination
of all discharges to the City of Claremont Collections System and termination of water services.
If any user is determined to be the source in whole or in part of a sanitary sewer blockage and or
overflow, the user will be assessed a fine of not less than 000.00, plus remediation costs for the
cleanup, in addition to any fines dispensed from the State of North Carolina. The fines contained
herein are not exclusive and the City Manager may use other methods to remedy the situation.
Enforcement of this FOG Control Program shall be conducted by the City in accordance with the
City of Claremont Sanitary Sewer Use Ordinance.
The City retains the right to review and modify this FOG Control Ordinance as necessary to
maximize its effectiveness in protecting the City's sanitary sewer system.
8

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Town of Cary
Sewer Use Ordinance — Fats, Oils, and Grease Control
Adopted by Town Council: December 10, 1998
Modified by Town Council: August 10, 2006
Sec. 36-183. Fat, oil, and grease control
(a) Scope and purpose, The objective of this section is to aid in preventing the introduction and accumulation of fats,
oils, and greases into the municipal wastewater system which will or tend to cause or contribute to sanitary sewer
blockages and obstructions. Food Service Establishments and other industrial or commercial establishments
generating wastewater containing fats, oils or greases are subject to this section. This section regulates such
users by requiring that grease interceptors and other approved strategies be installed, implemented, and
maintained in accordance with the provisions hereof.
(b) Definitions. The definitions contained in Section 36-172 and the following terms, when used in this section, shall
apply.
Action Level means the concentration based numeric value that the Grease interceptor effluent, at the device's outlet
tee and prior to mixing with any other waste water from the contributing establishment's property, are expected to
achieve on a consistent or stipulated basis.
Common interceptor means one or more interceptors receiving FOG laden wastewater from more than on
establishment. Common interceptors may be located at shopping centers, malls, entertainment complexes, sporting
arenas, hotels, multi -tenant "flex" spaces, mixed use spaces, and other sites where multiple establishments are
connected to a single grease interceptor. The owner of the property on which the common grease interceptor is
located shall be primarily responsible for the maintenance, upkeep, and repair of the common interceptor.
Fats, oils, and greases means organic polar compounds derived from animal and/or plant sources that contain
multiple carbon chain triglyceride molecules. These substances are detectable and measurable using analytical test
procedures established in 40 CFR 136, as may be amended from time to time. All are sometimes referred to herein as
"grease" or "greases" or "FOG".
Food Service Establishments or "FSE" means those establishments primarily engaged in activities of preparing,
serving, or otherwise making available for consumption foodstuffs and that use one or more of the following
preparation activities: Cooking by frying (all methods), baking (all methods), grilling, sauteing, rotisserie cooking,
broiling (all methods), boiling blanching, roasting, toasting, or poaching, and infrared heating, searing, barbecuing,
and any other food preparation or serving activity that produces a consumable food product in or on a receptacle
requiring washing to be reused.
FOG enforcement response plan means the document and written plan and procedures by which the director
implements an enforcement strategy applicable to the FOG control and management program established herein.
The plan applies to FOG program violations and matters of program noncompliance. Stipulated penalties for specific
and programmatic infractions are addressed in the plan and set forth in the Town's annual budget ordinance. The
director shall make site and case specific determinations of program non-conformance in accordance with this
Division 2.
Grease trap or interceptor means a device for separating waterborne greases and grease complexes from wastewater
and retaining such greases and grease complexes prior to the wastewater exiting the trap and entering the sanitary
sewer collection and treatment system. Grease traps also serve to collect solids that settle, generated by and from
activities that subject Users to this section, prior to the water exiting the trap and entering the sanitary sewer collection
and treatment system. Grease traps and interceptors are sometimes referred to herein as "grease interceptors."
Minimum design capability means the design features of a grease interceptor and its ability or volume required to
effectively intercept and retain greases and settled solids from grease -laden wastewaters discharged to the public
sanitary sewer.
Noncooking establishments means those establishments primarily engaged in the preparation of precooked foodstuffs
that do not include any form of cooking: but that may produce a consumable food product in or on a receptacle
requiring washing to be reused.
Page 1 of 4

Town of Cary
Sewer Use Ordinance — Fats, Oils, and Grease Control
On -site grease interceptor treatment (sometimes "On site Treatment") means mechanisms or procedures utilized by a
User to treat grease interceptor contents on the User's site, followed by the reintroduction of such treated wastewater
back into the interceptor. On -site grease interceptor treatment may only be accomplished by a User if the User or the
User's contract service provider is permitted by the NC Division of Waste Management as a septage management
firm or service provider.
Program Acknowledgement Certificate means program confirmation documentation issued by the Director. The User
is required to keep Program Acknowledgement Certificate on premises and produce it upon request of Town of Cary.
Service provider means any third party not in the employment of the User that performs maintenance, repair, and
other services on a User's grease interceptor at the User's directive.
%User is as defined in Section 36-172 for the purpose of this Section. Users include property owners who provide
common interceptors for one or more independent establishments, including tenants.
(c) Grease interceptor installation, maintenance, recordkeeping, and grease removal.
(1) Grease interceptors shall be installed and maintained at the User's expense, when a User operators a
food service establishment. Grease interceptors may be required in noncooking or cold dairy and frozen
foodstuffs establishments and other industrial or commercial establishments when the establishment
generates wastewater containing fat or grease and the director determines an interceptor is necessary to
prevent contribution or accumulation of grease to the sanitary sewer collection and treatment system.
Upon notification by the Director or designee that the User is subject to the terms of an enforcement
action, as stipulated in the FOG Enforcement Response Plan, said user shall not allow wastewater
discharge concentration from subject grease interceptor to exceed an establishment action level of 200
milligrams per liter, expressed as Hexane Extractable Material. All grease interceptors shall be of a type,
design, and capacity approved by the director and shall be readily and easily accessible for maintenance
and repair, including cleaning and for town inspection. All grease interceptors shall be serviced and
emptied of accumulated waste content as required in order to maintain minimum design capability or
effective volume of the grease interceptor, but not less often than every sixty (60) days or as permitted in
a valid program modification. Users who are required to pass wastewater through a grease interceptor
shall:
a. Provide for a minimum hydraulic retention time of 24 minutes at actual peak flow between the
influent and effluent baffles, with twenty-five percent (25%) of the total volume of the grease
interceptor being allowed for any food -derived solids to settle or -accumulate and floatable grease.
derived materials to rise and accumulate, identified hereafter as a solids blanket and grease cap
respectively.'
b. Remove any accumulated grease cap and solids blanket as required, but at intervals of not longer
than sixty (60) days at the user's expense, or in accordance with a valid program modification or
other director's requirements. Grease interceptors shall be kept free of inorganic solid materials,
such as grit, rocks, gravel, sand, eating utensils, cigarettes, shells, towels, rags, etc., which could
settle into this solids blanket and thereby reduce the effective volume of the grease interceptor.
c. If the User performs on -site grease interceptor treatment pursuant to a modification granted under
36-183(g)(5) below, User shall
1. Prior to commencement of Onsite Treatment obtain written approval by and from the
Director of all processes utilized in said Onsite Treatment.
2. If any pumped wastes or other materials removed from the grease interceptor are treated
in any fashion on -site and reintroduced back into the grease interceptor as an activity of
and after below, such on -site treatment, the user shall meet the criteria contained in (c)(1)(c)(3)
Page 2 of 4

Town of Cary
Sewer Use Ordinance — Fats, Oils, and Grease Control
3. Attain and adhere to the criteria listed below:
a. After 30 minutes of settling time, not more than 3.0 ml/L of settlable solids, as
measured in a 1 liter Imhoff cone shall be allowed, and;
b. Within and not more than 24 hours after onsite grease interceptor servicing,
not more than 2" (inches) of settlable solids and/or grease shall be allowed to
have accumulated therein as a result of said operations.
c. Service vehicles and equipment used in onsite Grease interceptor servicing
shall be registered with the Public Works and Utilities Department, and as
required by the North Carolina Division of Waste Management.
d. When servicing Grease interceptors service vehicles and equipment shall
have onboard, at all times, a certificate of approval for the operations and
methods used, issued by the Director.
e. Any tanks, tankage, or vessel(s) associated with a modification shall be
empty upon arrival at the initial FSE user site for which this modification is
intended to be applied.
d. Operate and maintain the grease interceptor to achieve and consistently maintain any applicable
grease action level . "Consistent" shall mean any wastewater sample taken from such grease
interceptor must meet the terms of numerical limit attainment described in subsection (c)(1). If a
User documents that conditions exist ("space constraints") on their establishment site that limit the
ability to locate a grease interceptor on the exterior of the establishment, the User may request an
interior location for the interceptor. Such request shall contain the following information:
1. Location of town sewer main and easement in relation to available exterior space outside
building.
2. Existing plumbing layout at or in a site.
3. A Statement of Understanding, signed by the User or authorized agent, acknowledging and
accepting conditions Director may place on permitting an identified interior location,
Conditions may include requirements to use alternative mechanisms, devices, procedures,
or operations relative to an interior location.
4. Such other information as may be required by the Director.
e. The use of biological or other additives as a grease degradation or conditioning agent is permissible
only upon prior written approval of the director. Any User using biological or other additives shall
maintain the trap or interceptor in such a manner that attainment of any grease wastewater, action
level, solids blanket or grease cap criteria, goal or directive, as measured from the grease
interceptor outlet or interior, is consistently achieved.
f. The use of automatic grease removal systems is permissible only upon prior written approval of the
director, the lead plumbing inspector of the town, and the Wake County Department of
Environmental Services or the US Department of Agriculture. Any user using a grease interceptor
located on the interior of the site shall be subject to any operational requirements set forth by the
North Carolina Division of Waste Management. Any User using this equipment shall operate the
system in such a manner that attainment of the grease wastewater discharge limit, as measured
from the unit's outlet, is consistently achieved as required by the Director.
g. The director may make determinations of grease interceptor adequacy need, design,
appropriateness, application, location, modification(s), and conditional usage based on review of all
relevant information regarding grease interceptor performance, facility site and building plan review
by all regulatory reviewing agencies and may require repairs to, or modification or replacement of
grease interceptors.
Page 3 of 4

Town of Cary
Sewer Use Ordinance — Fats, Oils, and Grease Control
(2) The user shall maintain a written record of grease interceptor maintenance for three years. All such
records will be available for inspection by the town at all times. These records shall include:
a. FSE name and physical location
b. Date of grease interceptor service
c. Time of grease interceptor service
d. Name of grease interceptor service company
e. Name and signature of grease interceptor service company agent performing said service
f. Established service frequency and type of service: full pumpout, partial pumpout, on -site
treatment (type of nature of operations)
g. Number and size of each grease interceptor serviced at FSE location
h. Approximated amount, per best professional judgement of contract service provider, of
grease and solids removed from each grease interceptor
i. Total volume of waste removed from each grease interceptor
j. Destination of removed wastes, food solids, and wastewater disposal
k. Signature and date of FSE personnel confirming service completion
I. Such other information as required by Director
(3) No nongrease-laden sources are allowed to be connected to sewer lines intended for grease interceptor
service.
(4) Access manholes shall have an installed diameter of 24 inches, a maximum weight of 50 pounds, and
shall be provided over each chamber, interior baffle wall, and each sanitary tee. The access
penetrations, commonly referred to as "risers" into the grease interceptor shall also be, at a minimum,
24 inches in diameter. The access manholes shall extend at least to finished grade and be designed
and maintained to prevent water inflow or infiltration. The manholes shall also have readily removable
covers to facilitate inspection, grease removal, and wastewater sampling activities.
(5) A User may request a modification to the following requirements of this ordinance. Such request for a
modification shall be in writing and shall provide the information set forth below.
(a) The user's grease interceptor pumping frequency. The Director may modify the 60 day grease
interceptor pump out frequency when the User provides data, and performance criteria
relative to the overall effectiveness of a proposed alternate and such can be substantiated by
the Director. Proposed alternatives may include: grease interceptor pumping or maintenance
matters, bioremediation as a complement to Grease interceptor maintenance, Grease
interceptor selection and sizing criteria, onsite grease interceptor maintenance, and
specialized ware washing procedures
(b) Grease interceptor maintenance and service procedures. The Director may modify the
methods) or procedures) utilized service a grease interceptor when the User provides data,
and performance criteria relatie to the overall effectiveness of a proposed alternate method or
procedure and such can be substantiated by the Director. If a modification to maintenance
and service procedures is permitted it shall be a conditional discharged permit approval.
(c) Any modification must be approved by the Director in written form before implementation by
the User or the user's designated service provider. The User shall pay modification fees as
set forth in the Budget Ordinance Fee Schedule.
Sec. 36-184. Severability.
If any provision, paragraph, word, section or article of this division is invalidated by any court of competent jurisdiction,
the remaining provisions, paragraphs, words, sections, and chapters shall not be affected and shall continue in full
force and effect.
Sec. 36-185. Conflict.
All other ordinances and parts of other ordinances inconsistent or conflicting with any part of this division are hereby
repealed to the extent of such inconsistency or conflict.
Page 4 of 4

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