HomeMy WebLinkAboutNC0040070_Staff Report_19911002To: Permits and Engineering Unit
Water Quality Section
Date: October 2, 1991
NPDES STAFF REPORT AND RECOMMENDATIONS
County: Gaston
NPDES Permit No.: NCO040070
MRO No.: 91-204
PART I - GENERAL INFORMATION
1. Facility and Address: City of Gastonia Water Treatment Plant
Post Office Box 1748
Gastonia, North Carolina 28053-1748
2. Date of Investigation: October 1 , 1991
3. Report Prepared By: W. Allen Hardy, Environmental Engineer I
4. Person Contacted and Telephone Number: Randy Hawkins, Senior
Opreator (704) 866-6023
5. Directions to Site: The Gastonia Water Treatment Plant is
located at the intersection of Falls Street and Long Street in
the City of Gastonia.
6. Discharge Point(s), List for all discharge Points:
Latitude: 350 16' 06"
Longitude: 81° 11' 16"
Attach a USGS Map Extract and indicate treatment plant site
and discharge point on map.
USGS Quad No.: F14SW
7. Size (land available for expansion and upgrading): There
appeared to be limited area available for expansion or
upgrading.
8. Topography (relationship to flood plain included): The
topography is rolling with slopes from 3-12%. The plant is
not located in the flood plain.
9. Location of Nearest Dwelling: There were several dwellings
located within 100 feet of the water plant.
10. Receiving Stream or Affected Surface Waters: UT to Long Creek
a. Classification: C
b. River Basin and Subbasin No.: Catawba 03-08-36
Page Two
C. Describe receiving stream features and pertinent
downstream uses: The receiving stream appeared to be
approximately 2-4 feet wide and had a distinct channel.
There did not appear to be much flow in the receiving
stream prior to the water plant discharge. There was a
stormwater pipe that provided most of the receiving
stream flow at a point beside the water plant discharge.
PART II - DESCRIPTION OF DISCHARGE AND TREATMENT WORKS
1. Type of Wastewater: 0% Domestic
100% Industrial
a. Volume of Wastewater: 1.2 MGD (Design Capacity)
b. Types and quantities of industrial wastewater: N/A
C. Prevalent toxic constituents in wastewater: Alum,
chlorine, and potassium permanganate are used in the
water purification process.
d. Pretreatment Program (POTWs only): N/A
2. Production Rates (industrial discharges only) in Pounds: N/A
3. Description of Industrial Process (for industries only) and
Applicable CFR Part and Subpart: N/A
4. Type of Treatment (specify whether proposed or existing): The
existing treatment consists of two (2) 0.600 MG holding
basins, which act as settling basins, and a sludge dewatering
press.
5. Sludge Handling and Disposal Scheme: The sludge is either
transported directly to the landfill or is carried to the
municipal wastewater treatment plant and is mixed with the
WWTP sludge prior to land application. The WWTP sludge is
land applied under permit WQ0001793.
6. Treatment Plant Classification: Less than 5 points; no rating
(include rating sheet). Class I
7. SIC Code(s): 4941
Wastewater Code(s):
Primary: 21
Secondary:
PART III - OTHER PERTINENT INFORMATION
1. Is this facility being constructed with Construction Grants
Funds (municipals only)? No
2. Special monitoring requests: No
Page Three
3. Additional effluent limits requests: No
4. Air Quality and/or Groundwater concerns or hazardous waste
utilized at this facility that may impact water quality, air
quality or groundwater? No air or groundwater quality
concerns are expected nor is hazardous waste utilized at this
facility.
5. Other: N/A
PART IV - EVALUATION AND RECOMMENDATIONS
The applicant, City of Gastonia, has requested the renewal of
the permit which allows them to discharge supernatant produced from
the sludge dewatering process at the water treatment plant. There
did not appear to be any site specific problems with the discharge
or the treatment facilities.
It is recommended that the permit be renewed to include any
monitoring deemed necessary by the Technical Review Group.
Q - 49-J-1- 11
Signature of Report 16eparer Datel
D.
Water Quality ional Supervisor Date
S�
12' 30"
1
0.07
2 MILS
,970 MAGNETIC NORTH
S_ CENTER OF SHEET
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S!jU7H G:•STONIA r.! '�;�. (CLOvtrc ,.vim •. •,_
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SCALE 1_.24000
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FEET
100p 0 1000 20G 1 KILOMETER
I 5
CONTOUR INTERVAL 20 FEET
DATUM IS MEAN SEA LEVEL
THIS MAP COMPLIES WITH NATIONAL MAP ACCURACY STANDARDS
FOR SALE BY U. S. GEOLOGICAL SURVEY
DENVER, COLORADO 80225, OR RESTON, VIRGINIA 22092
A FOLDER DESCRIBING TOPOGRAPHIC MAPS AND SYMBOLS IS AVAILABLE ON REQUEST
1 MILE
QUI
RATING SCALE FOR CLASSIFICATION OF FACILITIES
Name of Plant:.. LAI,, �� (�xs� n z1 U41� �Y e�� r •e r. ���,-.�
Owner or Contact Person: 1,o,,,Aj4 t�wksns t Se,.,Fo�
Mailing Address: _L74 —
------- —------- cksr. ,�, rt�1 �_ ZZ------------------
County: kScs.Sinel Telephone: (-Tp4) :961,,- 66,zs
NPDES Permit No. NC00 4do-7o Nondisc. Per. No.
IssueDate: MaU I . cyg7 Expiration Date:
Existing Facility ✓ New Facility
Rated By: Lke" 1- "0&4 Dater
Reviewed (Train. & Cert.) Reg. Office
Reviewed (Train. & Cert.) Central Office
ORC Grade
ITEM POINTS
ITEM POIN
(1) Industrial Pretreatment Units and/or
(4) PRIMARYTREATMENT UNITS
Industrial Pretreatment Program
(a) Septic Tank see definition no. 43
(see definition No. 33)
4
(b) Imhoff Tank ................................. .
(2) DESIGN FLOW OF PLANT IN GIRD
(c) Primary Clarifiers ............................
(not applicable to non -contaminated cooling
(d) Settling Ponds or Settling Tanks for Inorganic
waters, sludge handling facilities for water
Non -toxic Materials (sludge handling to .ilitiPs
purification plants, totally closed cycle
,for water purification—plaats, sand, gravel,
systems (def. No. 11), and facilities
stone, and other mining operations except
consisting only of Item (4) (d) or Items (4) (d)
recreational activities such as gem or gold
and (11) (d))
mining) ......................................
0 - 20,000 ..........................
1
(5) SECONDARY TREATMENT UNITS
20,001 50.000..........................
2
(a) Carbonaceous Stage
50,001 100,000 ..........................
3
(i)Aeration - High Purity Oxygen System .....
2(
100,001 -- 250,000 ..........................
4
Diffused Air System ...........
1 (
250,001 500,000..........................
5
Mechanical Air System (fixed,
500,001--1,000,000 ..........................
8
floating or rotor) ..............
f:
1.000,001 -- 2.000,000 ........................
10
Separate Sludge Reaeration .....
2,000,001 (and up) - rate 1 point additional for each
(ii) Trickling Filter
200,000 gpd capacity up to a
High Rate ...................
7
maximum of 30
Standard Rate ...............
E
Packed Tower ...............
`
(4
(iii) Biological Aerated Filter or Aerated
Design Flow (gpd) t�
Biological Filter ......................
1 (
(iv) Aerated Lagoons ..................... .
1 (
(v) Rotating Biological Contactors ..........
1(
(3) PRELIMINARY UNITS (see definition no. 32)
(vi) Sand Filters -
intermittent biological ....
2
(a) Bar Screens ................................
1
.
recirculating biological .....
3
or
(b) Mechanical Screens, Static Screens or
(vii) Stabilization Lagoons ...................
5
Comminuting Devices ...........
2
vni Clarifier
5
............
(c) Grit Removal ...............................
1
(ix) Single stage system for combined
or
carbonaceous removal of BOO and
(d) Mechanical or Aerated Grit Removal
2
nitrogenous removal by nitrification
...........
(e) Flow Measuring Device .......................
1
(see def. No. 12) (Points for this item
have to be in addition to items (5) (a)
or
(f) In Flow Measurement ..............
2
(i) through (5) (a) (viii) .................
8
(g)Preaeration
(x) Nutrient additions to enhance BOD
................................
2
removal...............................
5
(h) Influent Flow Equalization
2
(xi) Biological Culture ("Super Bugs") addition
...................
(i) Grease or Oil Separators - Gravity ..........
2
to enhance organic compound removal ...
5
Mechanical..........
3
Dissolved Air Flotation.
8
(i) Prechlorination ..............................
S
{b) -Nitoogenous Jtaye
t Aeration - High Purity Oxygen System .....
(7 9 Y Y9 Y
20 (i) Sludge Holding Tank - Aerated
' Diffused Air System ...........
................ 5
10 Non -aerated ............ 2
Mechanical Air System (fixed
0) Sludge Incinerator - (not including activated
floating, or rotor) ...... ......
Separate Sludge Reaeration .....
8 carbon regeneration) . 10
3 (k) Vacuum Filter, Centrifuge or Filter Press or other
(ii) Trickling Filler -
High Rate ..............
similar dewalering devices .................... 1 0
7
Standard Rate ............
5 (8) SLUDGE DISPOSAL (including incinerated ash)
Packed Tower............
5 (a) Lagoons ....
(iii) Biological Aerated Filter or Aerated
anon ... ace a . .
(b) Land Application (surface and subsurface)
Biological Filter .........................
10 (see definition 22a)
(iv) Rotating Biological Contactors ............
(v) Sand Filler-
10 -where the facility holds the land app. permit ... 1 0
intermittent biological
-by contracting to a land application operator who
2
........
recirculating biological ........
holds the land application permit ................ 2
3 -land application of sludge by a contractor who does
(vi) Clarifier ................................
5 not hold the permit for the wastewater treatment
(6) TERTIARY OR ADVANCED TREATMENT UNIT
(a) Activated Carbons Beds
facility where the sludge is generated ......... 10
(c) Landfilled (burial) ............................. 5
-
(9) DISINFECTION
without carbon regeneration ..................
5 (a) Chlorination
with carbon regeneration ....................
.............................. 5
1 5 (b) Dechlorination
(b) Powdered or Granular Activated Carbon Feed -
........................ 5
(c) Ozone
without carbon regeneration .................
.............................. 5
5 (d) Radiation
with carbon regeneration ...................
...... 5
15 (10) CHEMICAL ADDITION SYSTEM (S) (See definition No. 9)
(c) Air Stripping .............................
5 (not applicable to chemical additions rated as item
(d) Denitrification Process (separate process) .....
1 0 (3) 6). (5) (a) (xi), (6) (a), (6) (b), (7) (b), (7) (e),
(e) Electrodialysis ..............................
5 (9) (a), (9) (b), or (9) (c) 5 points each: List:
(f) Foam Separation .............................
5
(g) Ion Exchange ................................
5
5
(h) Land Application of Treated Effluent
5
(see definition no. 22b) (not applicable for
5
sand, gravel, stone and other similar mining
5
(11) MISCELLANEOUS UNITS
operations)
'(i) on agriculturally managed sites (See def.
(a) Holding Ponds, Holding Tanks or Settling Ponds -
for Organic or Toxic Materials including
wastes
No. 4)................................... 10 from mining operations containing nitrogen and/or
(ii) by high rate infiltration on non -agriculturally phosphorous compounds in amounts significantly
managed sites (includes rotary distributors
greater than is common for domestic wastewater 4
and sim'dar fixed nozzle systems) ...........
(iii) by subsurface disposal (includes low
..........
4 (b) Effluent Flow Equalization (not applicable to storage
basins
pressure
which are inherent in land application systems). 2
pipe systems and gravity systems except at
(c) Stage Discharge (not applicable to storage basins
plants consisting of septic tank and nitrifica-
inherent in land application systems 5
tion lines only) .............................
.......................................
4
(d)Pumps................................(i)
Microscreens..............................
..................................................................... 3
5 (e) Stand -By Power Supply..................................................................
(j) Phosphorus Removal by Biological Processes
3
(f) Thermal Pollution Control Device
(See def. No. 26) .............................
............................................. 3
20
(k) Polishing Ponds - without aeration .......
2
with aeration ..........
5
(1) Post Aeration - cascade ..............
0
(m) Reverse Osmosis...,,,•diffused or mechanical ...
5 TOTAL POINTS
,,,, .. ..............
(n) Sand or Mixed -Media Filters - low rate ...........
5
2
high rate ..........
(o) Treatment processes for removal of metal or
5 CLASSIFICATION
cyanide ....................................
(p) Treatment
........................................................ 5 - 25 Points
15 CPass
processes for removal of toxic
1
materials other than metal or cyanide .........
........................................................ 26- 50 Points
15. Class III
7) SLUDGE TREATMENT
....................................................... 51- 65 Points
Class IV ........................................................ 66- Up Points
(a) Sludge Digestion Tank - Heated ...............
Facilities having a rating of one through four points, inclusive,
10 do not require a certified operator. Classification of all other
Aerobic ...............
Unheated
5 facilities requires a comparable grade operator in responsible
charge.
......
(b) Sludge Stabilization (chemical or thermal) .......
3
S
(c) Sludge Drying Beds - Gravity ................
2 Facilities having an activated sludge process will be assigned
Vacuum Assisted .......
(d) Sludge Elutriation
5 a minimum classification of Class II.
.............................
(e) Sludge Conditioner (chemical or thermal) ........
5
5 Facilities having treatment processes for the removal of metal
(f) Sludge Thickener (gravity) ......................
(g) Dissolved Air Flotation Unit
5, or cyanide will be assigned a minimum classification of Class II.
(not applicable to a unit rates as (3) (i) .........
(h) Sludge Gas Utilization
8 \ Facilities having treatment processes for the biological removal
(including gas storage) .. ..
2 of phosphorus will be assigned a minimum classification of Class`
III.
.
DEFINITIONS
• (I)Activated Carbon Bads. A physicaVchemica. o,slhod lot reducing soluble organic mal.621 Iron
wastewater .01-1: the column-yp. bads used in IN. method will hat• a flow tale varying from two
to tight gallons par minute Pet squat& toot and may bo eithor upnow or downllow carbon hods. Carlson
may or may not be togenotatod on the wastewater treatment plant silo.
(2)Aeraled lagoon. A basin in which al sad& are mainuinod in suspension and by which biological
oxidation or *,panic matt.n is tudueed through arGlicialry accelerated transfer of otygon on a $low•
ifv..gh Oasis;
(7)Aatar',on. A process of dinging about intimate contact between a;r of high putily oxygen in a I;quid
by spraying, ag;faLon diffusion;
(4)A91iculIvlA4y managod 1;1o. Any silo on which a atop Is p advc.d, managed, and ha,vostod (Cie;)
includes grassos, grains. Iroos, ale);
(S)Aif Stripping. A process by which the ammonium ion it 6/11 converted to dissolved ammonia (pH
adjustment) with the ammonia than released to the almAsphate by physical ratans; or other t;mila,
procossos which remove pouoleum products such as bonaena, toluene, and xylona.
(6)Catbon Roger.4ralion. The regeneration of exhausted carbon by the use 01 a furnace to provide
oalrsmefy high temperatvres which votatlize and oxidize the absorbed impurities:
(2)Carlsonacoovs Stage, A slag* of wastewater ltea:monl designed to Ach;ova 'secondary' olllvont
(e)Conuitvge. A mechanical dovieo in which centrifugal [oleo Is used to separate solids (rom liquids
andtof to separate liquids of different don,il;u•
(9)Chem;cal Addition Syslams - Tits addition of chemical (s) to wastewater al an applies lion point far
purposes of improving solids removal. PH adjustment, alkalinity control, etc.; the capability to
o,P-I;ment with different chemicals and diflorent 3pP6cation points to achieve a specific result win be
considered one Syxlom: 111* capab;lity to add chemical (a) to dual units will be rated as once sy.lun.:
capablily to add a chemical al difference application points for dilinent purposes will result in the
systems bung tale as sop era la system,
(10)Chomicsl Sludge Conditioning, The addition of a chomcal compound such as time, lotr;c chloride, or
a Poymsf to war sludge to eoal.tco the mass prior to ;u appfical;olt to a dowaloring device;
(1 I)Closod Cycle Syslomt. Us* of holding ponds or holding lanks for containment of wastewater
eontauwng inorganic, non•Iouc materials from sand, gravel, crushed stone or other similar opoations,
from which that. is no discharge to the surface watt!-: such systems ship carry a maximum of two
points rogardless of pumping lacl'dies w any other appvnonances;
(12)Combined Removal of Carbonaceous 600 and Hitrog.novs Removal by Nitrification - A singis stage
system •dergnad' Ie achieve 'advanced' pormil olnu—I rueils on 600 and ammonia nitrogen within
the same biological reactor.
(U)OA-chlorination. The perlial or complete reduction of residual chlor;no in a liquid by any chamical
of physical Process;
(14)0eeitfilkl6on Process. The conversion of nitrato-nittogan 10 rsiuog.n gas'
(IS)Ehtclfodialysts, Place" lot I*mov;ng ionized sells from waist through the use o1 ion-adeclivt
ion--xchanq. membrane.;
(16)Flt.f Piss$, A process operated mechanically for partially dowxloring sludgy
(17)Foam S4p3t4f;on. The planned frothing of was[tw2l4f or wastewater .Illuant at a moans of
ismovirg excessive amounit or detergent materials through the introduction of aft In the form at line
bubbles; also c"od loam fractionation'
(Is)Grit Rainiest. The Process of romov;ng grit and other heavy mineral matter from wastewater:
(19)Imholl Tank. A deep Iwo story waslewalet link consisting of an upper sodimenlalion chambor and
a lower sludge digestion chamber,
(20)Instrumanb.d Flow Maasuement. A device which indicates snorter ,.cords rate of now:
(21)lon Etchings. A chomicai Process in which ions from two diffaranl motsculos ate exchanged'
(22)Land application: (a) Sludge Disposal, A final sludge disposal method by which sludge may be
applied to land o;th.t by spraying on the surface of by subsurface injection (I.*.. ch;sd • real
applicable fur described typos of sludge descred in (11) of We Rule): (b)Traaled Elfluent. Thwprocess of
spraying trealed wastewater onto a land list of other methods of awe&lion 01 wasl4w2ter onto a
land area as a means or final disposal Andre! leatmonl:
(20)IAkeosce-A. A low speed, continuously back.washed, totaling drum Gl:ef operating under
gravity conditions at t polishing method removing suspended solids from effluent;
(24)NAri6ication Process. The biochemical conversion of unosid;zod nitrogen (ammonia and organic
niuogan) Io ox;d;z.d nitration (usually nil,tle):
(2S)Niuog.nouz Soso. A separate stage of wastewater treatment designed for the specific pwpose of
converting ammon;a eiuogon to nilrate nitrogen:
(26)PhosPhxlf Removal Biological, The removal of phosphorus Irom wastewater by an oxictanoxic
proeats designed to enhance luxury uptake of phosphorus by the. microorganisms;
(22)Potishfn9 Pond. A holding pond lolowirg secondary Uoatm. nil with sufficient deunlion to allow for
the sellliN 01 &rely suspended solids; 1
(26)Posi Aeration Aoration lolbw;ng conventional secondary treatment Veils to incnass effluent D.O. .
or for any that purpose:
(29)Poso Aeration (Cascade) A pa h;ng method by which dissolved oxygen is added to the .Ifive t by
I norvn.chan;cal, gravity means a( Mill; down a sori.s of slips Ot waits; The Now occurring across
the steps e1 weirs nsovos in a lafrly thin layer And the operation of the catcade ,.quires ne oporalof
adjuslmonl: thus, ten points are assigned .van though this is an essential slop to moo
tug tha "it of
the d;schergo permit:
(70)Pewder.d at Granular Activated Carbon Food. A biophyskal carbon process that utilizer biological
aclivily and organic absorption by us$np powdered or granular activated carbon• Virgin and/or
,tgonverted canben is load controlled Into the trefoils:
(3I)P/0a*t31ion. A lank constructed to provide aeration prior to primary Veetmonl•
(7Z)Pnlimi6ary Wilts. Unit operations in the treatment process, such as screening and comminution,
that peoples the liquor lot subsequent major operations;
(77)Indusu;xt Petre.tment: (A)Prs-tr4%Un4nl Unit, Industrial. The conditioning of a waste at Its source before ditchs'gs, to Ismove of to neutralize substances Injurious to *-wens and lroalmdnl
Processes or to fiber a partial'odvc4on in load on a In atrnanl Process which Is operated by the tam.
governing body as the wasewater Ireabrrtonl plant being (ated; (b)Pte-I(oatmon$ P102raoq Industrial -
must be A Start Of EPA required program to rocsiv. points on thst-tadng shoot:
134)P'Imary Cfatir;ors, The firer s4ll4ng links through which wastewater Is passed in A I(aalmsell
works for the jawpos. of removing settleable and suspended solids and 800 which is associated with the
tolids:
(75)Pumps. Air influonk effluent, and in -plant pumps;
(76)RAdiatiof. Oisinlaclion and/or ""'144 lion process utilizing devices smiting uluav;olol 91 gamma
rare;
(]T)Revelse Osmosis. A treatment process in which a heavy contaminated liquid is pfessudzed
(Hough a membrane forming noaB1 pun liquid ill* from suspended sods;
(Js)Aolaling Biological Conue[ors. A ,lead biological growth placate in which wastewater 110w5
Through links in which a series or paltiAlly submerged circular surfaces are totaled•
(79)Sand Flters:(apnlorm;ll•nl Biological. Filtration of effluent following toplic links, 939004s, or
some other Poalm.nl peace,, in which further biodoeompos;lion it expected to produces desired
olllvonts: Hydraulic ,*.ding rate, on Ih.se !Ater- at. computed In gpdAe and her. a f.sulting low
9PMtf (test than one): Ib)R ec;ncvla ling biological . ch. tame type of e.nd 611.r as 4e4nad In (a) with
the added dapAbi4ly to #•cycle .Invent back through be sand filter:
(40)Sand of W..d•M.dia Filters. A polishin9 Proca-s by which .Ifluenl 4mks at. achi... d through a
further eduction at suspended solids:(a)luw felt -- gravity, hydraulically loaded filter with loading
"I" ;n the on- le three ppmtaf 1an9e:(b)h;gh at. -- a Pe.s hydraulically loaded filter with loading
,ties In the rms 9yNtf tango: At any rate, the loading rate will exceed tree gpfwsh
(41)Secondary ClariGors. A link which follows Me biological unit of a treztresnl plan, and which has
the purpose of removing sludge associaed with the biological vaavnool Utica'
02)S-Pata10 Sludge Reaeralion. A pan of the contact stablitation process whore the activated slvdgo
is Iranstorted to a tank and totaled before '*turning it to the batin:
(U)S.ptk Tank. A dn91e-dory s-.u6esq link In which settled tivelge Is in contact with the wastewater
Ilowinp Ihrough the lank; shalt nor be applicable lot septic lank systems sorting sing,. ,amity
rosidences having A capac;y of 2000 gallons or lass which ditchar9e to a niu;Gcation field:
(44)Sludge Digestion. The process by which organic or volatile matter and sludge is gasified, liquefied,
mineralized or convened into mote stable organic matter through the aclivily of living organisms,
which indud*s aerated holding lank.:
(45)Studgo Ory;ng Dods. An sees eompe;sI g naluial or artificial layers of porous malerials upon which
digested eewag. sludge is dried by draimge and ovapatalion:
(46)Sludgs Eblrialion. A process of sludge conditioning in which certain constituents ar& removed by
successive washings with both water or plant *Invent:
(42)Slud94 Gas Utilization. The Process of using sewage gas for the purpose of heating buildings,
laving anginas, ale.'
(4e1Sludge Holding lank (Atellod and Nomorated). A lank utilized lot small waslawator treatment
r4-1, not eonfalning A d;guslof In which dvdge may feu kepl Lech, and wpomat>nl w;11dr.,wn p,;o, to
a drying method (i.e. slvdgo dying Welt): This may be done by add;ng a small amount of a;, simply to
keep [be sludge flesh, but not nocotsatily an amount that would be togvued to achieve tiabilizi6on of
otgxnic mallor. A nonasntod lank would simply be used to decant trudge oiler so dowaiorLs9 and would
simply be used to docent sludge prior to d*waler;ng and would evil allow long periods (several days of
detention) without 'osult;ng odor piobloms:
(49)Slvdgo Incinolalots. A lurnaco dot;gnod to built tludgs and to remove all moisture and combvsl;Wo
matar;als and raduc& the sludge to a stand- ash•
(SO)Sludge Stabilization (Chemical or Thermal). A Process to make treated sludge loss odorous and
puuastrible, and to reduce the pathogenic organism content; This may be done by pH adjustment
chlorine dosing, or by heal uoalmeni:
(SI)Sludge Thickener. A type of sedimentation lank ;n which the sludge is permitted to .ere. and
thicken through agilalion and gravity;
(52)SIab;4za Goes lagoon. A type of oxidation lagoon in which biological oxidation of organic matter is
affected by natural transfer of oxygen to the water team air (not a polishing pond);
(S7)Stand-By Power Supply. On site or portable electrical gonuatirg equipment;
(54) Static Screens. A stationary scsoen designed to remove solids Including non•biodegradablo
particulals (floatable solicit, suspended solids and 800 (oduction) from municipal and Incivsttial
wastewater treatment systems'
(55)Talliary Treatment. A stage of Gaalmsnl lollowing secondary which is primarily for the purpose
of effluent polishing; A soiling lagoon or sand or coal ,ante nigh, be employed for this purpose.
(56)Thermal Pollution Control Oov;e*. A device Providing lee the transfer of heal from a fluid flowing
;n tubes to 2noth4t fluid outside the rubes, or vice versa; or, other moans of [&quilting
liquid lemperabures•
(S))Thetmal Sludge Conditioner. A conditioning Procost by which heal is added for a prouacl*d period
of time to Improve the dowalerabil;ty of sludge by the tolubiliting and hydrautizing of the smat$er and
non highly hydrated sludge particle.•
(SB)Tox;e Materials. Those wasps w eoenlsrnal;ons of wastes including disease -causing agents which
,[Ise discharge and upon oapasurt, ingaslion, inhalation a assimilation into any organism either
dsocdy from the envitonmonl or indr.cdy by ingestion through food chains, will cause death, disease,
behavioral abnormalities, sanest, genetic mutations, physiological malfunctions (including mapuned0ns
in reproduction) or physical deformations, in such organisms of their offspring: Toxic materials
include, by way illustration and not limitation• load, cadmium, chromium, mercury, vanadium,
ateenie, line, orlho-nitro-ehlorebonz.ne (ONCE polychlorinated b;phenyls (PCBs) and dichlotodiphonyl
trichforoothano (DDT): and any other materials that have or may hersahat be delormined to have toxic
properties;
(S9Jbickling fiber- A biological treatment unit consisting of material such as broken snots, or lock
over which wattswalor is distributed: A high tale trickling Idler is one which is operalea-al bo: veen
10 and 30 mild per acre. A low rate trickling IAter Is one which is designed to operate at one'se low
mqd pre acre:
(60)Mckling Fluor (Packed Tower). A plug grow type of operation in which wastewater flows down
Waugh successive layers 01 media or filtrate material; 019AAk material is rometvod continuaCy by
active biological fixed growth in each successive layar. This method may produce -secondary' cualiiy
ofllut i. cr may be adapted to product a nitrifrod effluent;
(61)Vaeuum Filters, Centrifuges, or Filter Presses, Devices which ere designed to remove excess
water Irom either digested or und'gsst4d sludge prior to disposal or further Irealmont.
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