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HomeMy WebLinkAboutWQ0006537_Final Permit_19940225State of North Carolina Department of Environment, Health and Natural Resources Division of Environmental Management James B. Hunt, Jr., Governor Jonathan B. Howes, Secretary A. Preston Howard, Jr., P.E., Director LT:.W?F,A 1 T4 49 0 ±L1 C)EHNR February 25, 1994 Mr. Kazuo Uehara, President and Plant Manager Kobe Copper Products, Incorporated Post Office Box 160 Pine Hall, North Carolina 27042 Subject: Permit No. WQ0006537 Kobe Copper Products, Inc. Wastewater Facilities Stokes County Dear Mr. Uehara: In accordance with your permit renewal application received December 7, 1993, we are forwarding herewith Permit No. WQ0006537 dated February 25, 1994, to Kobe Copper Products, Incorporated for the continued operation of the subject wastewater collection and storage facilities. This permit shall be effective from the date of issuance until January 31, 1999, and shall be subject to the conditions and limitations as specified therein. Please pay particular attention to the monitoring requirements in this permit. Failure to establish an adequate system for collecting and maintaining the required operational information will result in future compliance problems. Issuance of this permit hereby voids Permit No. WQ0006537 issued July 23, 1993. If any parts, requirements, or limitations contained in this permit are unacceptable, you have the Tight to request an adjudicatory hearing upon written request within thirty (30) days following receipt of this permit. This request must be in the form of a written petition, conforming to Chapter 150E of the North Carolina General Statutes, and filed with the Office of Administrative Hearings, P.O. Drawer 27447, Raleigh, NC 27611-7447. Unless such demands are made this permit shall be final and binding. If you need additional information concerning this matter, please contact Mr. John Seymour at (919) 733-5083. Sincerely, ,n rn 0— LOT, c i2 SDS A. Prest Howard, Jr., P.E. cc: Stokes County Health Department Winston-Salem Regional Office, Water Quality Winston-Salem Regional Office, Groundwater Groundwater Section, Jack Floyd Training and Certification Unit Facilities Assessment Unit Mr, Stephen Shi, Attorney (Petree Stockton, 1001 West 4th St.,Winston-Salem, N.C. 27101-2400) P.O. Box 29535, Raleigh, North Carolina 27626-0535 Telephone 919-733-5083 FAX 919-733-9919 An Equal Opportunity Affirmative Action Employer 50% recycled/ 10% post -consumer paper NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION DEPARTMENT OF ENVIRONMENT, HEALTH AND NATURAL RESOURCES RALEIGH WASTEWATER COLLECTION AND STORAGE PERMIT In accordance with the provisions of Article 21 of Chapter 143, General Statutes of North Carolina as amended, and other applicable Laws, Rules, and Regulations PERMISSION IS HEREBY GRANTED TO KOBE COPPER PRODUCTS, INCORPORATED Stokes County FOR THE operation of a wastewater collection and storage facility (which includes cooling water that contains some grease and oil that mixes with the process water in the normal operation of the plant) which consists of an 18,000 cubic foot wastewater storage lagoon, a 25 GPM duplex grinder pump tank with high water alarms, to serve Kobe Copper Products, Inc. with no discharge of wastes to the surface waters, pursuant to the permit renewal application which was received on December 7, 1993, and in conformity with the project plan, specifications, and other supporting data subsequently filed and approved by the Department of Environment, Health, and Natural Resources and considered a part of this permit. This permit shall be effective from the date of issuance until January 31, 1999, and shall be subject to the following specified conditions and limitations: 1. The wastewater collection and storage facilities shall be effectively maintained and operated at all times so that there is no discharge to the surface waters, nor any contamination of ground waters which will render them unsatisfactory for normal use. In the event that the facilities fail to perform satisfactorily, including the creation of nuisance conditions or failure of the irrigation area to adequately assimilate the wastewater, the Permittee shall take immediate corrective actions including those actions that may be required by the Division of Environmental Management, such as the construction of additional or replacement wastewater treatment and disposal facilities. 2. The issuance of this permit shall not relieve the Permittee of the responsibility for damages to surface or groundwaters resulting from the operation of this facility. 3. The residuals generated from these treatment facilities must be disposed in accordance with General Statute 143-215.1 and in a manner approved by the North Carolina Division of Environmental Management. 4. Diversion or bypassing of the untreated wastewater from the treatment facilities is prohibited. I . The facilities shall be properly maintained and operated at all times. 2. Upon classification of the facility by the Certification Commission, the Permittee shall employ a certified wastewater treatment plant operator to be 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 8A, .0202. The ORC of the facility must visit each Class I facility at least weekly and each Class II, 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 must comply with all other conditions of Title 15A, Chapter 8A, .0202. 3. The facilities shall be effectively maintained and operated as a non -discharge system to prevent the discharge of any wastewater resulting from the operation of this facility. 4. Freeboard in the storage lagoon shall not be less than two (2) feet at any time. 1. Any monitoring (including groundwater, surface water, soil or plant tissue analyses) deemed necessary by the Division of Environmental Management to insure surface and ground water protection will be established and an acceptable sampling reporting schedule shall be followed. 2. A water analysis shall be performed each time the quench tanks are emptied. This analysis shall include, but shall not necessarily be limited to: Chromium Cadmium Copper Nickel Lead Zinc 3. Three copies of all records as specified in conditions 111. 1, 111.2, and any other data as may be required shall be submitted on or before the last day of the following month to the following address: NC Division of Enviroinnental Management Water Quality Section Facility Assessment Unit PO Box 29535 Raleigh, NC 27626-0535 5. Noncompliance Notification: The Permittee shall report by telephone to the Winston-Salem Regional Office, telephone number 910/ 896-7007 as soon as possible, but in no case more than 24 hours or on the next working day following the occurrence or first knowledge of the occurrence of any of the following: a. Any occurrence at the closed loop or recycle system facility which results in the treatment of significant amounts of wastes which are abnormal in quantity or characteristic, such as the dumping of the contents of a sludge digester, the known passage of a slug of hazardous substance through the facility, or any other unusual circumstances; 2 b. Any process unit failure, due to known or unknown reasons, that renders the facility incapable of adequate wastewater treatment, such as mechanical or electrical failures of pumps, aerators, compressors, etc.; c. Any failure of a pumping station, sewer line, or treatment facility resulting in a by-pass directly to receiving waters without treatment of all or any portion of the influent to such station or facility; or d. Any time that self-monitoring information indicates that the facility has gone out of compliance with its permit limitations. Persons reporting such occurrences by telephone shall also file a written report in letter form within 15 days following first knowledge of the occurrence. This report must outline the actions taken or proposed to be taken to ensure that the problem does not recur. 1. The lagoon must be lined with a 30 mil high density polyethylene liner installed in accordance with the requirements of the approved plans and specifications. 2. Following installation and inspection of the lagoon liner, and prior to waste disposal operations, certification of the liner's compliance with approved construction specifications and the liner's integrity must be provided to the Division of Environmental Management Groundwater Section, by the project engineer. 1. Adequate inspection, maintenance, and cleaning shall be provided by the Permittee to insure proper operation of the subject facilities. 2. The Permittee or his designee shall inspect the wastewater treatment and disposal facilities to prevent malfunctions and deterioration, operator errors and discharges which may cause or lead to the release of wastes to the environment, a threat to human health, or a nuisance. The Permittee shall keep an inspection log or summary including at least the date and time of inspection, observations made, and any maintenance, repairs, or corrective actions taken by the Permittee. This log of inspections shall be maintained by the Permittee for a period of three years from the date of the inspection and shall be made available upon request to the Division of Environmental Management or other permitting authority. 3. Any duly authorized officer, employee, or representative of the Division of Environmental Management may, upon presentation of credentials, enter and inspect any property, premises or place on or related to the disposal site or facility at any reasonable time for the purpose of determining compliance with this permit, may inspect or copy any records that must be maintained under the terms and conditions of this permit, and may obtain samples of groundwater, surface water, or leachate. UWAR _11 FaTelg 10. v I In► 1. This permit shall become voidable unless the facilities are constructed in accordance with the conditions of this permit, the approved plans and specifications, and other supporting data. 2. This permit is effective only with respect to the nature and volume of wastes described in the application and other supporting data. 3. This permit is not transferable. In the event there is a desire for the facilities to change ownership, or there is a name change of the Permittee, a formal permit request must be submitted .to the Division of Environmental irlanagement accompanied by an application fee, documentation from the parties involved, and other supporting materials as may be appropriate. The approval of this request will be considered on its merits and may or may not be approved. 4. Failure to abide by the conditions and limitations contained in this permit may subject the Permittee to an enforcement action by the Division of Environmental Management in accordance with North Carolina General Statute 143-215.6(a) to 143-215.6(c). 5. The issuance of this permit does not preclude the Permittee from complying with any and all statutes, rules, regulations, or ordinances which may be imposed by other government agencies (local, state, and federal) which have jurisdiction. 6. A set of approved plans and specifications for the subject project must be retained by the Permittee for the life of the project. 7. The annual administering and compliance fee must be paid by the Permittee within thirty (30) days after being billed by the Division. Failure to pay the fee accordingly may cause the Division to initiate action to revoke this permit as specified by 15A NCAC 2H.0205 (c)(4). The Permittee, at least six (6) months prior to the expiration of this permit, shall request its extension. Upon receipt of the request, the Commission will review the adequacy of the facilities described therein, and if warranted, will extend the permit for such period of time and under such conditions and limitations as it may deem appropriate. 9. Issuance of this permit hereby voids Permit No. WQ0006537 issued July 23, 1993. Permit issued this the 25th day of February, 1994 NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION &'J"CAl, A. Preston oward, Jr., P. ., Director Division ofEnvironmental Management By Authority of the Environmental Management Commission Permit Number WQ0006537 4 385 2'30" 587 11 700000 FEET n;aorsON z-7 Mt. IrA �� ' ��' 4- 1 � L -j 69 KobeIf . �••- cam, ,. t. J � •�-, �; {1�_v' 00 -151 '� f J� \�� `��:, �'•< 'L'� l Se feu; zjiusd �� ���• �- -.�`—� - 6 ;cam ��h 1 �'1>�� 1�.� A �' , � �.V� r/ U, 1/r( � � �,�_\s � rf���� ./ ; I � �, oc. � ., s�r�-�\\;�i� n ��• �'� X70 `@\` �� � y ! /( : � ✓�• �,�//fes \\f .. % �• � � �;� �a�a;le !/ `fib � `��`�-•-�,_!-•e��/> ..'�,/��°>°: _ � � � r;�� 56 IOU ��f - j • � � � � � t _ �-Jl X 30/00411 rte.."\ _ff- i 38 iii F 1 STCb `•11, r -'BMS �• �� �� - �Zr° �t \ I ' ✓ / 4 ` i m -e • �J .'�� `�� "' :ter-'•-- o : ;'�•c� a fy" r` ` =�� ~`J� �° 7 e Jill.� \. yr �,. vfy ;:� i /'•� .RATING SCALE FOR CLASSIFICATION OF WATER POLLUTION CONTROL SYSTEMS Name of Facility: k-6 k4e- if P/Z 1 IZ rXu c � Owner or Contact Person: ��erlr4 /�v Mailing Address: �9._ ��G A,0 /t" C. 7 o z County: 5Ya A'—C s Telephone: Present Classification: "-' New FacilityExisting Facility �— NPOES Per. No. Now 'r Nondisc. Per. No.W 0 -L0 -L22L5-.0 Health Dept.Per No. Rated by: ( Telephone(`ZZ/O 9f(c, `70a 7 Date: ° 2-03 Reviewed by: Health Dept. Telephone: �E Regional Office Telephone: 6Zo)sy6- r,,c''-r Central Office Telephone: ORC:Grade: Telephone: Check Classification(s): Subsurface Spray Irrigation Land Application Wastewater Classification: (Circle One) 0 II 111 IV Total Points:__ SUBSIPFACE CLASSFrAT10N (check all units that apply) 1. septic tanks 2. pump tanks 3. siphon or pump -dosing systems 4. sand Filters 5- grease trapAnterceptor 6 oVwater separators 7` _gravity subsurface treatment and disposal; 8. pressure subsurface treatment and disposal: SPRAY IRFIGAkTK)N CLAS51F)CATltil (check all units that apply) 4. _preliminary treatment (definition no. 32 ) 2. lagoons 3. septic. tanks 4-- pump tanks 3. _lpumps 6. _sand flham 7_ grease traplinterceptor 8- oil/water separators 9`_d€s€nfection 10. chemical add"stion for nutrient/atgae 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 APPLICATIOK/RESIDUALS CLASSIFICATION (Appres only to permit holder) 1. land application of biosolids, residuals or contaminated soils on a designated site. WASTEWATER TREATMENT FACIUYCLASSIFIC4Ti061 The following systems shall be assigned a Class 1 cassilicalion, unless 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 Finer Systems consisting only of septic tanks, dosing apparatus, pumps,sand finers, disinfection and direct discharge; 3_Lagoon Systems consisting only of preriminary treatment, lagoons, pumps, disinfection, necessary chemical treatment for / algae or nutrient control, and direct discharge; 4. Closed-loop Recycle Systems; 5. _,-_Groundwater Remed€anon Systems consisting only of ell/water separators, pumps, sir -stripping, carbon adsorption, disinfection and dispos.J; 6. Aquacufture operations with discharge to surface waters; 7 Water Plant sludge handling and batik -wash water treatment; 8- Searood processing consisting of screening and disposal. s. Single-family discharging systems, wish the exception of Aerobic Treatment Units, will be classified if permitted alter July 1, 1993 or if upon Inspection by the Division, it is found ]hat the system is not being adequately operated or maintained. Such systema will be notified of the classification or re classification by the Commission, In writing. Fachl0gs having a rating of one through four points, Inclusive, do not require a cera filed operator. Facllitles having an acflvated &fudge process will be assigned a minimum ciassiflcation of Class IL Facllhles having tmaf nerd processes Tor the removal oh metal or cyanide will be assigned a minimum classification of Class it. Facilities having treatment processes for the biological removal of phosphorus will be assigned a minlmurn classification of Class III. AU DEFINITIONS The lollowing definflions shall apply throughout thla Subchapter. (1) Activated Carbon Beds. A physicatichemical method for reducing sotuble organic malarial from wastewater effluent; The column -type beds used in this method will have a lbw rate varying from two to eight gallons per minute per square loot and may be elther upffow or downflow carbon beds. Carbon may or may not be regenerated on the wastawafar treatment plant she; (2) Aerated Lagoons. A basin in which all solids are maintained In suspension and by which biological oxidatlon or organic matter is reduced through artificially accelerated transfer of oxygen on a flow-through basis; (3) Aerallom A process o1 bringing about Intimate contact between air or high purity oxygen In a liquid by spraying, aghatlon or d1ffuslon;(3a) Extended Aeration. An activated sludge process utilizing a minimum hydraulic detention time of 18 hours. (4) Agricuhurafly managed she. Any she 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 converted to dissolved ammonla (pH adjustment) with fine ammonia then released to the atmosphere by physical means; or other similar processes which remove petroleum products such as benzene, toluene, and xylene; (6) Carbon Regeneration. The regeneratlon 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 st:.ige of wastewater treatment designed to achieve 'secondary' effluent Ilmfls; (8) Centrifuge. A mechanical device In which centrifugal force is used to separate soflds from liquids or to separate liquids of different densir,as; (9) Chemical Addition Systems- The addhlon of chemicai(s) to wastewater at an application point for purposes of Improving solids removal, pH adjustment, -LIkallnity control, etc.; the capability to experiment with drllerent chemicals and ddferem appllcatlon polms 10 achieve a specific rasuh will be considered one -stem; 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 irposes will result in the tyslems being rated as separate systems; 11G) Ch9r6ical Sludge Condliloning. The addition of a chemlcal compound such as lime, ferric chloride, or a polymer to wet sludge to coalesce the mass prior to Its application to a dewatering device', (1 i) Closed Cycle Systems. Use of holding ponds or hofdlnrg tanks for containment of wastewater contalntng 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 appurlenances; (12) Combined Removal of Carbonaceous BOD and Nitrogenous Removal by Nhrffication- A single stage system required to achieve permit effluent linalis on BOD and ammonla nhrogen within the same biological reactor, (15) Dechlorination. The partial or complete radv6on of residual chlorine in a ilquid by any chemical or physical process; (14) Denitrification Process. The conversion of nitrate-nhrogen to nitrogen gas; (I) Post Aeration - cascade ............. ......................................................................... ........................................ diffusedor mechanical........................................................................................................2 (m) Rovers* Osmosis...................................................................................................................... 5 .................. (n) Sand or Mixed -Media Fiffem - low rate ...... ....................................................................................... 2 ldghrate......................................................................5 (o) Treatment processes for removal of metal orcyanide................................................................................--.1 5 (p) treatment pmcosses for removal of toxic materials other than metal or cyanide... .... _._ ._ ._ ..._. ....Z 5 (7) SLUDGE TREATAAEPIT (a) Sludge Digestion Tank - Heated (anaerobic)..,, .................... . ..... ........ ....... . ....... ........ ...................... 10 Aerobic...................................................................................... ....... Unheated(anaerobic). .. ........................................................................•--•---.......................3 (b) Sludge Stabilization (chemical or thermal) ................. ................. .... ........................................................... S (o) Sludge Drying Beds - Gravity......................................................................................................................2 VacuumAssisted......................................................................................................................................5 (d) Sludge Elutriation... ... ..................................................................................................5 (e). Sludge Conditioner (chemical or thermal)......... ............... ... ..................................... .. ............................. 5 (f) Siudge Thickener (gravity) ............................................... ..........................................................................5 (g) Dissolved Air Flotatlon Unit [not applicable to a unit rated as(3)(1))........................................ .................... e (h) Sludge Gas Utltizatton (including gas storage)...........................................................................................2 (l) Sludge Holding Tank - Aerated ............... ...... .................. ..._........ ....................... ............................... .......... No n- se rated.................................................................................................................... ......................... 2 {[) Sludge Incinerator (not Including activated carbon regeneration)................................................................1 0 (k) Vacuum Filter, Centrifuge, or Filter Press or other similar dewatering devices.. . . .......1 0 (a) RESIDUALS UTILIZATIOWDISPOSAL (inducing Incinerated ash) (a) Lagoons........................................................................................................................................... (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 orlandfill permil........................................................................................................................................2 (c Dedicated Landfill(burial) by the permlttee of the wastewater treatment facility .............. ... ._.. ..... ...._._..5 (�) (a) Chlorination.............................................................................................................................................5 (b) Dechlorination ............................................. ......................... .,... ._............................................................5 (c:) Ozone..............................................................................................................................................5 (d) Radiation..................................................................................................................................................5 (10) CHEMICAL ADDITION SYSTEM(S) ( see definttlon No. 9) [not applicable to chemical addhIons rated as hem (3)Q). (5)(a)(xl), (6)(a), (6)(b), (7)(b), (7)(a), (9a), (9)(b) or (9)(c) 5 points each: Ust........— ..... ............ .................................... ................. _... ......................... .....................3 .... ..................................................................................................................................5 ...................................................................................................................................5 .............. .......................................................................................................................5 (1 1) WSCSIANE-OUS UNU&PROCESSES (a) Holding Ponds, Holding Tanks or Settling Ponds for Organic or Toxic Materials Including wastes from mining operations containing nhrogen or phosphorus compounds In amounts signHkarx)y greater than Is common fordomestic wastewater.......................................................................................................................... (b) Effluent Flow Equalization (not applicable to storage basins which are inherent In Land appllcalfon systerns).. (c) (d) Stage Discharge (not appiicabte to storage basins Inherent in land awlication cystemis)... .....----- Pumps..........................................................................................................................................I...... (e) Stand -By Power Supply ................................................ (1) Thermal Poilutbn Control Device.................................................._.....�.............................................. ..3 TOTAL POINTS .......................... _........................................... CLASSFICATM ClassI..... .......... ........................................................................................... 5-25 Polyds Class11....... .......... ....... ................................................................................ 26-50 Points Cbssli........................................................................................................51-65 Points --------------------------------------------------------- ClassN ................ .......... .......... .......... ........ .............. ............................... 66.Up Paints Fachl0gs having a rating of one through four points, Inclusive, do not require a cera filed operator. Facllitles having an acflvated &fudge process will be assigned a minimum ciassiflcation of Class IL Facllhles having tmaf nerd processes Tor the removal oh metal or cyanide will be assigned a minimum classification of Class it. Facilities having treatment processes for the biological removal of phosphorus will be assigned a minlmurn classification of Class III. AU DEFINITIONS The lollowing definflions shall apply throughout thla Subchapter. (1) Activated Carbon Beds. A physicatichemical method for reducing sotuble organic malarial from wastewater effluent; The column -type beds used in this method will have a lbw rate varying from two to eight gallons per minute per square loot and may be elther upffow or downflow carbon beds. Carbon may or may not be regenerated on the wastawafar treatment plant she; (2) Aerated Lagoons. A basin in which all solids are maintained In suspension and by which biological oxidatlon or organic matter is reduced through artificially accelerated transfer of oxygen on a flow-through basis; (3) Aerallom A process o1 bringing about Intimate contact between air or high purity oxygen In a liquid by spraying, aghatlon or d1ffuslon;(3a) Extended Aeration. An activated sludge process utilizing a minimum hydraulic detention time of 18 hours. (4) Agricuhurafly managed she. Any she 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 converted to dissolved ammonla (pH adjustment) with fine ammonia then released to the atmosphere by physical means; or other similar processes which remove petroleum products such as benzene, toluene, and xylene; (6) Carbon Regeneration. The regeneratlon 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 st:.ige of wastewater treatment designed to achieve 'secondary' effluent Ilmfls; (8) Centrifuge. A mechanical device In which centrifugal force is used to separate soflds from liquids or to separate liquids of different densir,as; (9) Chemical Addition Systems- The addhlon of chemicai(s) to wastewater at an application point for purposes of Improving solids removal, pH adjustment, -LIkallnity control, etc.; the capability to experiment with drllerent chemicals and ddferem appllcatlon polms 10 achieve a specific rasuh will be considered one -stem; 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 irposes will result in the tyslems being rated as separate systems; 11G) Ch9r6ical Sludge Condliloning. The addition of a chemlcal compound such as lime, ferric chloride, or a polymer to wet sludge to coalesce the mass prior to Its application to a dewatering device', (1 i) Closed Cycle Systems. Use of holding ponds or hofdlnrg tanks for containment of wastewater contalntng 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 appurlenances; (12) Combined Removal of Carbonaceous BOD and Nitrogenous Removal by Nhrffication- A single stage system required to achieve permit effluent linalis on BOD and ammonla nhrogen within the same biological reactor, (15) Dechlorination. The partial or complete radv6on of residual chlorine in a ilquid by any chemical or physical process; (14) Denitrification Process. The conversion of nitrate-nhrogen to nitrogen gas;