NC0025526_Staff Report_19940104

NPDES DOCUHENT :SCANNING: COVER :SHEET
ANA
ANN
NPDES Permit:
NC0025526
Walnut Cove WWTP
Document Type:
Permit Issuance
Wasteload Allocation
Authorization to Construct (AtC)
Permit Modification
Complete File - Historical
Staff Report '
Speculative Limits
Instream Assessment (67b)
Environmental Assessment (EA)
Permit
History
Document Date:
January 4, 1994
This document is printed on reuse paper - ignore any
content on the reirerse side

cc: Permits and Engineering
Technical Support Branch
County Health Department
Central Files
WSRO
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SOC PRIORITY PROJECT: YES X NO
IF Yes, SOC No.: EMC WQ 92-21
To: Permits and Engineering Unit
Water Quality Section
Attention: (Jay Lucas)
AUTHORIZATION TO CONSTRUCT
NPDES PERMIT REPORT AND RECOMMENDATIONS
Date: January 4, 1994
County: Stokes
Permit No. NC0025526
PART I GENERAL INFORMATION
1. Facility Name and Current Address: Town of Walnut Cove
(facility location) (mailing address)
off of NCSR 1918 PO Box 127
Walnut Cove, NC Walnut Cove, NC 27052
2. Date of most recent NPDES Staff Report: October 7, 1992
3. Changes since previous action on NPDES Permit: None known
4. Verify Discharge Point(s) on plans with current NPDES Permit.
List for all discharge points.
Latitude: 36°17'36" Longitude: 80°07'47"
Attached is a USGS map extract with discharge point on map.
U.S.G.S. Quad No. B-18SW U.S.G.S. Name Walnut Cove
5. Treatment plant classification: Class II (see attached rating
sheet)
PART II - DESCRIPTION OF DISCHARGE AND TREATMENT WORKS
1. Existing treatment facility:
a. What is the current permitted capacity of the facility?
192,000 gpd

b. Date(s) and construction activities allowed by previous
Authorizations to Construct issued in the previous two
(2) years: NONE
c: What is the actual treatment capacity of the current
facility (design volume)? 192,000 gpd
d. Please provide a description of existing or substantially
constructed wastewater treatment facilities: Dual
facultative lagoons with chlorination. (Surface aerators
have been added to lagoons in an effort to improve
treatment.)
2. Please provide a description of proposed wastewater treatment
facilities: Mechanical influent screening; influent lift
station; flow measurement; valve "splitter" vault; parallel
sequencing batch reactors (SBRs); valve vault; effluent
equalization basin; equalization pumps; and UV disinfection.
3. Residuals handling and utilization/disposal scheme: Sludge is
to be wasted from SBRs into existing "lagoon #2". This
reviewer did not find any other information pertaining to
sludge disposal in the submittal.
4. Important SOC, JOC or Compliance Schedule dates: Note:
modified SOC was signed by Town Manager on 6-8-93. State has
yet to sign SOC.
Date
Submission of Plans and Specifications 7-15-93(rcvd 11-10-93)
Begin Construction 12-31-93
Complete Construction 12-31-94
PART III - EVALUATION AND RECOMMENDATIONS
Frankly, this writer believes that a less costly treatment
alternative is available to the Town of Walnut Cove. Using the
existing, now partially aerated lagoons, one could simply add
automatic backwashing filters after the lagoons, and achieve
consistent compliance with Permit limitations.
However, considering the submittal as presented, the following
comments are offered:
1 - Ultra Violet disinfection is proposed. Per a recent Memo from
Raleigh, it is this office's understanding that UV
disinfection will not be allowed unless preceded by a filter.
This office supports Raleigh's position on this issue.
However, it is understood that SBRs should produce a very
clean effluent from domestic wastewater.
2 - Information on solids handling is not provided. Thorough

calculations are needed showing: solids that will be generated
along with predicted frequency of wasting; storage capacity of
sludge lagoon; and adequate aeration of sludge lagoon.
Information is needed demonstrating how sufficient mixing and
stabilization of solids will be provided, and how sludge will
ultimately be disposed.
3 - A telemetry warning system was not noted in submittal.
Considering the small size of the Town and the limited
personnel available, this would seem very prudent. In fact,
the current lift station and treatment plant is now operated
by a Contract Operator who is not even in Town much of the
time. (Good engineering judgement would seem to merit this
option of 15A NCAC 2H.0219(h).)
4 - Is grit removal needed before the lift station and treatment
system? The Design Engineer stated that his only concern with
grit would be the automatically controlled plug valve for
wasting of sludge.
5 - A flow measurement device does not appear to be specified on
the plans. The specifications reference open channel and
magnetic flowmeters. More information is needed on proposed
flow measurement device(s).
6 - Is automatic stand by power.to be provided? The plans show a
generator slab. Again, this office strongly supports
telemetry with whatever type of backup power system is
proposed.
Information gathered from a few people around the State
familiar with SBRs, indicates that these units "can" provide a
reasonable degree of consistent treatment. This is provided the
Operator is familiar with this type of treatment and stays on top
of things. Industrial applications seem well suited to these units
because of "down time" periods.
As with any activated sludge type of treatment, wash -outs due
to excessive Inflow/Infiltration is of concern. Since the Town has
had lagoons, I/I has not been of great concern in the past. SBRs
may possibly handle I/I better than other types of "flow thru"
systems. Nonetheless:
7 - This office would like to see the Engineer furnish reliable
information on the extent of I/I in the Town's collection
system. Have there been any bypasses prior to the influent
lift station, and are the reported flow values in the past
accurate? Have specific I/I sources ever been found and
eliminated?

Once the above items have been satisfactorily addressed, this
office does not object to the issuance of an A/C for this project.
Signature of report preparer ate
/24'1i
Water Quality S rvisor
Date

RATING SCALE FOR CLASSIFICATION OF WATER POLLUTION CONTROL SYSTEMS
Name of. Facility: ki A L a ‘4.-1- C 0 1 j.% CU 774 / . o, o s E ,o
Owner or Contact Person: J 1f V► 0 EvLc / -re w At A1, .4. 6 t
Mailing Address: 1'• 0. 6Gx /2 7 1.4.4 N u-r C. vE ,, n/ C. 2 70 SZ
County: 57Ox c s Telephone: (7/ o0 5"7 / - 4-8 0
Present Classification; r New Facility '- Existing Facility
NPDES Per. No. NC00 ZsSZ ( Nondisc. Per. No.WQ Health Dept.Per No.___
Rated by: 1- it 6 • c Telephone: (yio) t4 c - 7c r 7 Date: / - 4 -Y 4
Reviewed by: _ , _ Health Dept. Telephone:
Regional Office
U Central Office
ORC: jE-N,s 64oCI
Grade:
Check Classification(s): ___ Subsurface _ Spray Irrigation
Wastewater Classification: (Circle One) I II III IV
Telephone: b 9 (--700'7
Telephone:
Telephone: (9, 0) Yy6,- eF4t
Land Application
Total Points: 4-1
J4PLANT PROCESSES AND RELATED CONTROL_ EOUIPMR'IT WHICH ARE AN INTEGRAL PART OF INDUSTRIAL_ eFIODUCTION SHAM NOT RE
!!►s • i A :_yl 1: - lts:►I a 1 L- ��•
. -. _ 1! ► — i J1.
AND GRA vrry MrRIFICATION LINES ARE EXEMPT FROM CLASSIF)CATION.
JI.
SLESURFACE CLASSIFICATION
(check all units that apply)
1, .septic tanks
ZL..---.Pump tanks
3.__siphon or pump -dosing systems
4,..sand Stem
5,, grease trapfinteroeptor
6. ,of/water separators .
7. gravity subsurface treatment and disposal:
8,pressure subsurface treatment and disposal:
SPRAY IRR GA flON C ASSSFICATION
(check ail units that apply)
1.__preliminary treatment (definition no. 32 )
2,—_la9oons
3. septic tanks
4pump tanks
5,pumps
6.._.__sand filters
7. grease trap/interceptor
e on/water separators
9. disinfection
10. chemical addition for nutrient/algae control
11._spray irrigation of wastewater
in addition to the above classifications, pretreatment of wastewater in excess of these components shall
be rated using the point rating system and will require an operator with an appropriate dual certification.
LAND APPLICATION/RESIDUALS CLASSIFICATION (Applies only to permit holder)
1. Land application of biosolids. residuals or contaminated soils on a designated site.
WASTEWATER TREATMENT FACIUTYCtASSIFICATION
The following systems shall be assigned a Class I classification, yntess the flow is of a significant quantity or the technology is unusually
complex, to require consideration by the Commission on a case -by -case basis: (Check if Appropriate)
1. _OiVwater Separator Systems consisting only of physical separation, pumps and disposal;
2, Septic Tank/Sand Fitter Systems consisting only of septic tanks, dosing apparatus. pumps.sand filters. disinfection
and direct discharge;
3 Lagoon Systems consisting only of preliminary treatment, lagoons. pumps. disinfection, necessary chemical treatment for
algae or nutrient control, and direct discharge;
4. Closed -loop Recycle Systems;
5- Groundwater Remediation Systems consisting only of oil/water separators, pumps. air -stripping, carbon adsorption. disinfedion
and disposal;
6, Aquacutture operations with discharge to surface waters;
7. Water Plant sludge handling and back -wash water treatment
8. Seafood processing consisting of screening and disposai.
8ti Single-family discharging systems. with the exception of Aerobic Treatment Units, will be classified if permitted after July 1.
1993 or if upon inspection by the Division, it is found that the system is not being adequately operated or maintained. Such
systems will be notified of the classification or reclassification by the Commission, in writing.

The foilowing scale Is used for rating wastewater treatment facilities: (circle appropriate points)
ITEM
POINTS
(1) (industrial Pretrsstmsnt Units or Industrial Pretreatment Program (sae definition No. 39).w.•-»w......N..•...N.w»•..•••w..w•�
(2) DESIGN FLOW OF PLANT IN gpd (not applicable b non.00ntamtnated cooing waters, sludge handing taciUliss for
water purification plants. totally closed cycle systems(see definition No. 11). and facilities consisting only of kern
(4Xd) or hams (4)(d) and (11)(d))
o-iY.00�o/N►Nw•w•NNw.N•.rN•wNNNM..wN N..Nov«Nw•N«w•N«N••w.w•»N•wN«NNNNN•.N1
20.001 • 50.000.••.••....•....w•ww.•....... w.w.-•••w•••..••••••w•••••.•Nw••w•••••w.-...•..N.NNNNw.2
50.001 • 100.000..•••••••0••w••N.w«...•.w••••N•.ww••...ww.•Nw.r•.•w....•w•N - w•N••«.2
100.001 • 250.000..w.w..r••. w•.••w.•••w•••.•.•....•..•w.......•ww.•••.••w.•••••••.•••••••-•••••w•
250.001 500.000«»N.••••••.••••••N••.••..•.•..•w•••.ww.•.•ww.w..••w••••w•w•.••w.•«w•«.ww•w.wwNN...•w .5
500.001 • 1.000.000••]w•N••«N««•«••w•w•••NN.N.«•ww••««•••••ww.wN•••N•N•w•«•w••••wNNwww«NN»w»«
1.000.001•././0.000»w-.•.ww....w..N...w.w.....N.NN•.......w....w...•...w•N•wNNw..rN.w..••.•.ww.wN.•..10
2.000.001 (and up) rate 1 point additional for each 200.000 god capacity up b a maximum of _.».N...N.aO
Design Row (gpd) sac�. oc o
(3) PREUMNARY UNITS/PROCESSES (see definition No 32)
(a) Bar Scalene ..•w.•..•........................•.••••-...•w.....••ww•••••..••..wwwwwww•. ....-..•»•...»•.1
Of
(b) CM
Screens. Static Screens or Comminuting Dsv N..»w. N.»w........>
(c) Grt Removal»wow .....wwww•.•ww....•..••.. »......»..».».1
Of
(d) Mechanical or Aerated Grl Removal.»......«.wNN.wwwww«...N.
(e) Plow Measuring Devkiew.«N•w••.••..•w•••wow.«.•.N.N•«.«.««•.«•«••«.•««••N-'-ww•N»•Nwwwwww».»».w.»•
w
(4) P))RM RYTREATMENT WRSIPRXE5SE5
(a) Septic Tank (see definition No. 43
(b) Whet( TaNc.«ww......w.N»w«»Nov.w«N»Nov.wN««ww.w..»..«»w«.....«.wNNNw.Nww......N..»«N»•N«w..5
(e) Primary ClarWiers....,.»N».....«».».N««...«»»w....«..»»..N«.««w....»»NN».NN»«wN........».....«...»w.w«N».«.Ji
d) Settling Ponds or Seating Tanks for inorganic Non toxic Materials (sludge handling facilities for water
purhficatbn plants. sand, gravel. stone. and other mining operations except recreational activities such as gem
or gold mining)....»......»ww.•.wwwwww.....wwww•••••• ..w«»N».».w 2
(5) SECONDARYTREATM9VT
(a) Carbonaceous Stage
(I) Asratbn-High Purity Oxygen Syrtis 0
Diffused Air System....ww....•.•••.•www.•-Nwww..•...••••• Se
Mechanical Air System (fixed. floating or rotor) - .
Separate Sludge Reasratbn.N.N.w•..--......w.»...•..».........».«.•.ww......«•wN...w..•...N..»..2
(0) Trlakting Ater
HighRatew«».Nww.www»«»N.ww- _ .....—...........---2
Standard Rate»»..«ww«wNNNw»w».....««NN.wN.N«N».....Nw.........w....».«...w.»wNwa
Packed Tower.«..».....N«»««.».».»«...«».»«.»»N»»N»»»ww«»«».».w.........»..»».«»« -5
(111) Biological Aerated Filter or Aerated Biological Hiner ....•«.................»»»..-•--- 10
(Iv) Aerated Lagoons.........»«.».«.N.w«.»».»..»»w»«w.....N»«.»Nw«»»».».««»»»..»»N»w10
(v) Rotating Biobgkd ContadorsN..•»...wwwww•.... ..w».••..•••••.••N•.•ww•••w.10
(vi) Sand Fillers -Intermittent bblogl 2
Recirculating biological..NNNNNw.ww...»N««.N.- ---.«N.N.»».NN.»«««««»»........».».-«•.11
O Stabllizatbn Lagoons•••N.w..wwN....•..w..•N NO. N S
Cartier •..«.•N•».»«•.NNM•»»•N•N..N«••N««.»•.•.••• ... ....».»».N«.w».3
(lot) Single stage system for combined carbonaceous removal of BOD and nitrogenous removal by
nitrification (see dsilnhion No. 12)(Points for this hem have to be in addition to items
(5)(a)(I) through (5)(a)(v111).
utilizing the extended aeration process (see definition No.3a)..w»..-...•.•••••.•.•.•......wN-..®
utilizing other than the extended aeration process..___....»». .....•-••-0
�x) Nutrient additions to enhance BOO removal..«.w.....wow«.»wow.«»—.»«.w.....«.--..5
xl) Bbbgicat Cuhurs ('Super Bugs')addhlon.N .... ..............3
(b) Nitrogenous Stags
(1) Aeration - High Purity Oxygen System. ...•-»»•«»--_...«»w_»»»•» ...20
Diffused Air System.--.... .......w.»...»..»».w»N..»...N....»..»««10
Mechanical Air System (fixed. floating or rotor).....N»...w»...»..»..N...»»...-».»...»«.»«-N».2
Separate Sludge Reaeratbn.••-••-wN•».«••••••ww.....www..••....«-w......•..•.... •....3
Cu) Trickling Filter -High Rate.N»«..».».........»...N»»N...».....N.»..»»«......».».»N»»........»...N»..a
Standard Rate..NNN.NM•Nov«N»»•»«..•N..•••N..»•N.N»»•N.••..•.•....wNN•.«•«.NN»•..N»»•NN.»5
Packed Tower....»N»...•.••.».•.w..»N»N..NN••••.»...».•«N»N...».N«NN.».w«••.•..N•.•»«••-•••«»5
(10) Biological Aerated Filter or Aerated Biological. Flhar....»....»»-...-».NN.N».N.«..-•-»-»-.»---.10
Iv) Rotating Biological Contactors.....»►«ww....««....-......»....N.N.«N......-«••N•NN«•«•ww.«.10
(v) Sand Alter • intermittent biological...•....•....-..-•..•...N.....w...............N...w.•.......»...wwwNZ
gaffer._
blotogical....N.....N....».......................................w........«........««.-....«.......�
(v() ga er....w .....N....... •..•..•«...•..••••..•..........•....•..•......•.•......N....N....5
TERTIARY OR ADVANCED TREATMENT I)II15rPROCESSES
(a) Activated Carbon Beds •
without carbon regeneratton•w...........w..w.»«.....N••..•--•w-•«..-.-.•..•N••-•••N•N...•»•••N-...•..........il
with carbon regeneration.....-..N.ww.........-.w•.•www......»-..w».»•.»w«--•w...N..»..-.....»15
(b) Powdered or Granular Activated Carbon Feed -
without carbon regeneration.......N•.......w.........«-..N.....N....11.N.....Nw....«N.......... ......-•..3
with carbon regenerationww w......N...»..N..-........--.-»-»...w..-N...N.......................15
(a) Air strippingNI/ ...............•.•....•.......•...•....•w-..•••...ww•.-........».......... ON ... ......a
(d) Denhrilication Process•..•.•...•...-•»•........»......N..N..N....wN
•..••.....•....-.••.••..•..•-...N...........w .••10
e) Electrodlalysis•:.•........•••...........•...............-..•.........w..N.•....»....•....w.•.w ' .5
(f) Foam Separation.............. 3
(g) ion Exchange S
(h) Land Application of Treated Etfluenl (see definition No. 22b) (not applicable for sand. gravel. stone
and other similar mining operations) by high rate Mllitration.N...................N............. ....... ..--............N•4
(1) Microscreens -» ~~ S
P) Phosphorous Removal by Biological Processes (Soo definition No. 26) .«•.•••••..«••••»20
) Polishing Ponds - without aeration.».N.N............N.-......-.N....N..................«.•.............-....NN.....N.....••N..•NN2
with aeration.........-«.••N....Or. .w...-••...................•..•..•--....-..-•...••.•N...•..•--..•--.•.•••«••••«.•«S
N...2
N...N..N»N..w».»««N.»N»NM•MwM
(5)
(f) lrstrumsntsd Flow MsasursmsnL....N .
511) Prue ratlon...•-.•.•••••••.•••••• «NNwwNN«wNY• •
•N..w......•.. .-
% h p..wN..wNN»
1srr srr}-Fbw Equatetatton.ww..•.....w•••w...w•.-..•.. ...•.•..•••..•..•.-.w.. N.»
(I) Grease o�r� Oil Separators • Gravity.. - - -
Machin_icai....•N«w.wNN.....• MNNNwNN..-.---.•.N••.•••N«w.««»».ww»wN.N•«Nw«w.w-««-N»•wM.N..••.N.-3
Dtasotved Air F l a..•w•NwNww•••••• .N••wN.•»wwwN••N»wow.•w•.«•»•««wwww.«w—N—»-.•-•N2
Prechbrtnatbn•-..ww•..•••••............w•w..•w..w•..wwwwww«•••••• .«.ww«w«..«•-•«.a

(1) Post Aeration • cascade............NNN.NNNNN...N•N•.N....•.NN•.••..NNN.NN«N.N.N• ... .0
diffused or mechanical...-.-...N..NN.NNN.NN .....NN ..2
(in) Reverse Osmosis....NN..........NNN NN.............N.N. ---.--NN.N..NN.N...N...N........ 5
(n) Sand or Mixed -Media Filters • low rateN.N•N....N....N..NN....NNN..N-N...N....N...N.N.N....NN.N....� ..N..•-......N...2•
highrate............. NN.....N•N...N.....NN.•..N.N.......•.•..•• .5
(o) Treatment promisee for removal of metal or cyanide ............. N....... N.N...N.N..N...... 15
(p) . treatment processes for removal of toxic materials other than metal or cyanide-.----
..---•..---.1
(7) SLUDGETREAD IT
(a) Sludge Digestion Digestion Tank - Heated (anaerobic)...N.N..N..N...NN._...NN.NN.N....N....... N.N....N....... N.N...........10
Ae�ic.....NNN......N•NN.N•.NN•N•N•NN•M•••N..N..... N•... ••• 5
Unheated (anaerobic) N..N.....•NN.NNNN.N.N•N• 3
(b) Sludge Stabilization (chemical orthermal)...N.N•N..N••N.N...... ...NN.NNNN..NN.N...N..NN..NN.... ...NS
(c) Sludge Drying Beds - Gravity.N-.....N...N.N.N-N..NN......N.N....N.N.N..N.NN......•NN.N.N.N.NN.».N.N.N.N....N...N---.2
Vacuum Assistod.N•N.........N.•.... N.N. N..NN..N.N.. ...•.....N•••N.••.•N«. 5
(d) Sludge Etutriatbn.NN.........N..NN....... N•N••N••N•N•N•N•••................ N•••-•••N••••NN••••NN•••••NN••N..•.N••• 5
(e) Sludge Conditioner (chemical or thermal)►.N►•N.•..N....NN....-NN..•...••.N....NN.WN•••••N•NN•NN••••N•NN•N••N5
(f) Sludge Thickener(gravity)....N........ N••..••NN. N..........N..N...•NN 5
(g) Dissolved Air Flotation Unit (not applicable to a unit rated as (3)(t))..............NN.N.N•-- .8
(h) Sludge Gas Utilization (including gas storage)......._.......N.N.N.NNNN..... NNN..N.N»N.•..N..N..N.N....... NN2
(1) Sludge Holding Tank - Aerated.....N...N.•NNN.•N•NN•NNN.NNN•NNNN.••N••• •.••••••• - 5
Non-aeradad N. 2
()) Sludge incinerator (not Including activated carbon regeneration) N. 10
(k) Vacuum Fitter. Centrifuge. or Filter Press or other similar dewatertng devices-...•.NN•.NNN. .10
(a) RESIDUALS UTILIZATION/DISPOSAL (including incinerated ash) /�
(a) Lagoons...-. ,Q
(b) Land Application (surface and subsurface) (see definition 22a)
by contracting to a land application operator or landfill operator who holds the Land application permit
or landfill permit N. N. 2
(9) (c) Dedicated Landfill(burfat) by the perrmlttee of the wastewater treatment facility---__.---.-....—.—.-...5 DtSWECTEN
(a) Chlorination 600000N••••NN••••••.N.•N•NN••••N•N•N•••N••N•..N•NN•.NN••••NN•►N•N►NN. N. N.NNNN.N....N. •.....N.S
(/b� )■/Dee�chbrination••••••NN.N•N•NNNN•MN••N-•••••N•NN••N•••N•N•NNNN••••N••.•••N•N•N...• 5
(C) o�N•.NN.N•NNN..N•N►N.N•NNN•.N•N.NN.N►N►NN....•N••N..NN•N•.•N.NNN.NN• •••
(d) Radiation ...... N..N..•NN.•N 5
(10) CHEMICAL ADDITION SYSTEM(S) ( see definition No. 9) [not applicable to chemical additions rated as Item (3)Q).
Us(a)(xl). (6)(a). (6)(b). (7)(b), (7)(e). (9a). (9)(b) or (9)(c) 6 points each:
.N.N..NN...N.N....N..NN.•N.N..-•N N.N•N.N► •...N.N...... N.N.N....N.. .5
NNN•...N......... NNN•..NN..NN•.NN••.NN.N...N. •NN•-N 5
••N••NNN•NN NN••NN•NN NN••N••••N• •••.• ••. 5
......N.N••..NNNN•N ...N..NNN..NN.N.NNNNNNN•NN•.NNNNNN.N.•.•..N..••N•••N.•5
(11) MISCELLANEOUS UNTTSIPROCESSES
(a) Holding Ponds, Holding Tanks or Settling Ponds for Organic or Toxic Materials including wastes from mining
operations containing nitrogen or phosphorus compounds In amounts significantly greater than Is common
for domestic wastewater
(b) Effluent Flow Equalization (not applicable to storage basins which are inherent In land application systems)_
(c) Stage Discharge (not applicable to storage basins Inherent In land application systems)--------
—
(d) Pumps..NN.N•....NN•N►....... .N•NN•N•N.•N.•NN•.NN.N. •NN .N • 6000000
(e) stand.By Power supply....N.N.NN.NM..NN.NNNN..NN.NN....N.N.N.•N•..N•NN. N.NN••••••NN•NN. N..N.N.N... ...N. (f) Thermal Pollutbn Control Device......... .N.N ..N.N.—........NNNNNN«NNN N•/
N .•••..........N....•N•.(.��. •�
TOTAL POINTS.N.N.NN.N•....••N.NN.N.N....N.N...N.N.N.N.NN.N.N.N.., 1 '�•4
CtASSIFICATICN
Gies/NN.N••••NN.N.N.N.•N•NN•NN....NNNN.•N•NN.N•NN.•N•NN•N.NN••N•N.N.NN 5-25 Points
Class Ii..•.N..NN...-NNN..N..NN.NN..NNNN.......N.NN.....NN.N..NNN....N•N•N. 26-50 Points
Ctrs Il••..•NN.NN..NN..NN.N•N.N•NN•.NN•N••.•NNNN•NN•N••••NN•N••NN••N.........NN.51-65 Points
Class IV- .N....NN..N.NN..N.•.NN.NNNN.NNN.NNN.......N.N••••.NN.NN•N••NN...N..NN. 68.Up Points
Facilities having a rating of one through four points. Inclusive. do not require a certified operator.
Facilities having an activated sludge process will be assigned a minimum classification of Class IL
Facilities having treatment processes for the removal of metal or cyanide will be assigned a mINmum classification of Class IL
Facilities having treatment processes for the biological removal d phosphorus will be assigned a minimum classification of Class 111.
.0004 DEFINITIONS
The following definitions shalt apply throughout this Subchapter.
(1) Activated Carbon Beds. A phystcaVchemical method for reducing soluble organic meleutal from wastewater effluent; The column -typo beds used In this
method will have a flow rate varying from two to eight gallons per minute per square foot and may be either upflow or downflow carbon beds. Carbon may or
may not be regenerated on the wastewater treatment plant site;
(2) Aerated Lagoons. A basin in which all solids are maintained In suspension and by which biological oxidation or organic matter is reduced through artificially
accelerated transfer of oxygen on a flow -through basis;
(3) Aeration. A process of bringing about Intimate contact between air or high purity oxygen In a liquid by spraying. agitation or dlffusion;(3a) Extended
Aeration. An activated sludge process utilizing a minimum hydraulic detention time of 18 hours.
(4) Agriculturally managed site. Any site on which a crop Is produced. managed. and harvested (Crop includes grasses. grains. trees. eta);
(5) Air Stripping. A process by which the ammonium ion is first comforted to dissolved ammonia (pH adjustment) with the ammonia then released to the
atmosphere by physical means; or other similar processes which remove petroleum products such as benzene. toluene. and xytene;
(6) Carbon Regeneration. The regeneration of exhausted carbon by the use of a furnace to provide extremely high temperatures which volatilize and oxidize the
absorbed impurities;
(7) Carbonaceous Stage. A stage of wastewater treatment designed to.achleve 'secondary effluent limits;
(8) Centrifuge. A mechanical device In which centrifugal force is used to separate solids from liquids or to separate liquids of different densi;tas:
(9) Chemical Addntton Systems- The addition of chemical(s) to wastewater at an application point for purposes of Improving solids removal. pH adjustment.
alkalinity control. etc.; the capability to experiment with different chemicals and different application points to achieve a specific result will be considered one
system; the capability to add chemical(s) to dual units will be rated as one system; capability to add a chemical at a different application points for different
purposes will result In the systems being rated as separate systems;
(10) Chemical Sludge Conditioning. The addition of a chemical compound such as lime. feric chloride. or a polymer to wet studge to coalesce the mass prior to
lts application to a dewatertng device;
(11) Closed Cycle Systems. Use of holding ponds or holding tanks for containment of wastewater containing inorganic. non -toxic materials from sand. gravel.
crushed stone or other similar operations. Such systems shall carry a maximum of two points regardless of pumping facilities or any other appurtenances;
(12) Combined Removal of Carbonaceous BOD and Nitrogenous Removal by Nitrification- A single stage system required to achieve permit effluent limits on BOD
and ammonia nitrogen within the same biological reactor;
(13) Dechlorinatton. The partial or comptete !eduction of residual chlorine in a liquid by any chemical or physical process;
(14) Denhrtficatbn Process. The conversion of nitrate -nitrogen to nitrogen gas;

eado 8roo
(rfiet
Taal riot Cove WWTP
NCO025526-001
RECEIVING STREAM: Town Fork Creek
Latitude: 36°17'36"
Longtitude: 80°07'47"
USGS Quad. No. : B-18SW
USGS Quad. Name: Walnut Cove