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HomeMy WebLinkAbout19951229 Ver 1_COMPLETE FILE_19950307State of North Carolina IT Department of Environment, MIIWA Health and Natural Resources 4 • Division of Water Quality James B. Hunt, Jr., Governor Wayne McDevitt, Secretary E) E H N A. Preston Howard, Jr., P.E., Director September 24, 1997 Wilkes County WQC 401 Project #951229 APPROVAL of 401 Water Quality Certification Coleman Long, Chief Planning and Environmental Branch U.S. Army Corps of Engineers Post Office Box 1890 Wilmington, N.C. 28402-1890 Dear Mr. Long: You have our approval, in accordance with the attached conditions, to place temporary fill in waters for the purpose of inspecting the structural integrity of W. Kerr Scott Dam and Reservoir as you described in your application dated September 16, 1997. After reviewing your application, we have decided that this fill is covered by General Water Quality Certification Number 3114 This Certification allows you to use Nationwide Permit Number 33 when it is issued by the Corps of Engineers. In addition, you should get any other federal, state or local permits before you go ahead with your project including (but not limited to) Sediment and Erosion Control. Coastal Stormwater, Non-Discharge and Water Supply Watershed regulations. Also this approval will expire when the accompanying 404 or CAMA permit expires unless otherwise specified in the General Certification. This approval is only valid for the purpose and design that you described in your application. If you change your project, you must notify us and you may be required to send us a new application. If total wetland fills for this project (now or in the future) exceed one acre, compensatory mitigation may be required as described in 15A NCAC 2H.0506 (h). For this approval to be valid, you must follow the conditions listed in the attached certification. If you do not accept any of the conditions of this certification, you may ask for an adjudicatory hearing. You must act within 60 days of the date that you receive this letter. To ask for a hearing, send a written petition which conforms to Chapter 150B of the North Carolina General Statutes to the Office of Administrative Hearings, P.O. Box 27447, Raleigh, N.C. 27611-7447. This certification and its conditions are final and binding unless you ask for a hearing. This letter completes the review of the Division of Water Quality under Section 401 of the Clean Water Act. If you have any questions, please telephone John Dorsey at 919-733-1786. 4incerely.n , oward, , r. P.E. Attachment ca Wilmington District Corps of Engineers Corps of Engineers Raleigh Field Office Winston-Salem DWQ Regional Office Mr. John Dorney Cenral Files 9512291tr Division of Water Quality • Environmental Sciences Branch Environmental Sdenoes Branch, 4401 Reedy Creek Rd., Raleigh, NC 27607 Telephone 919-733-1786 FAX # 733-9959 An Equal Opportunity Aiftrmadve Action Employer • 50% recycled/10% post consumer paper DEPARTMENT OF THE ARMY WILMINGTON DISTRICT, CORPS OF ENGINEERS P.O. BOX 1890 WILMINGTON, NORTH CAROLINA 28402-1890 IN REPLY REFER TO September 16, 1997 EAU sF,o ?FG ? ?9 Fo Environmental Resources Section Mr. Preston Howard, Jr., P.E. Acting Director Division of Environmental Management North Carolina Department of Environment, Health, and Natural Resources Post Office Box 29535 Raleigh, North Carolina 27626-0535 Dear Mr. Howard: This letter is in regar the stilling basin at W. Kez 951229). A scope of work dE and our intent to apply Nat: letter dated October 23, 19! Certification was provided L i `?A ctural inspections of n',1 roir (DEM Project No. ?j tnS. ( Y`om' -ering and dewatering o, aas transmitted by 'Vl 1? I 401 Water Quality ,_11. =r 28, 1995. The work previously scheduled to occur between September 15 and December 31, 1996, was not implemented at that time, due to scheduling conflicts. We plan to conduct this operation during the early fall or winter of 1997. Work may begin as soon as September 22, 1997, if river-flow conditions are conducive. It is our understanding that the 401 approval dated November 28, 1995, is valid under the revised schedule. This letter provides written notification of our revised schedule. Other aspects of the project are as described in previous correspondence. If additional information is required, please call Mr. Chuck Wilson of our Environmental Resources Section at (910) 251-4746. Sincerely, Coleman Long Chief, Planning and Environmental Branch r -2- Copy Furnished: VMr. John Dorney Division of Environmental Management North Carolina Department of Environment, Health, and Natural Resources 4401 Reedy Creek Road Raleigh, North Carolina 27607-6445 Mr. Steve Mauney Division of Environmental Management North Carolina Department of Environment, Health, and Natural Resources 585 Waughtown Street Winston-Salem, North Carolina 27107-2241 Mr. Franklin T. McBride Wildlife Resources Commission North Carolina Department of Environment, Health, and Natural Resources 512 North Salisbury Street Raleigh, North Carolina 27604-1188 Mr. Joe Mickey Wildlife Resources Commission North Carolina Department of Environment, Health, and Natural Resources 155 Timberbrook Trail State Road, North Carolina 28676 Mr. Jim Meed Division of Water Resources North Carolina Department of Environment, Health, and Natural Resources Post Office Box 27687 Raleigh, North Carolina 27611-7687 DEPARTMENT OF THE ARMY WILMINGTON DISTRICT, CORPS OF ENGINEERS 1 P.O. BOX 1890 6 O? 5W WILMINGTON, NORTH CAROLINA 28402-1890 \ '? Ne REPLY TO I/ C ATTENTION OF August 8, 1996 Environmental Resources Section i' 0 Mr. Preston Howard, Jr., P . E . ??4y Jam! Acting Director Division of Environmental Management ^?scF North Carolina Department of Environments Health, and Natural Resources Post Office Box 29535 Raleigh, North Carolina 27626-0535 Dear Mr. Howard: This letter is in regard to proposed structural inspections of the stilling basin at W. Kerr Scott Dam and Reservoir (DEM Project No. 951229). A scope of work describing required coffering and dewatering and our intent to apply Nationwide Permit No. 33 was transmitted by letter dated October 23, 1995. Your approval of 401 Water Quality Certification was provided by letter dated November 28, 1995. As discussed with Mr. Greg Price by telephone on July 31, 1996, the work originally scheduled to occur between October 31 and December 31, 1995, was not implemented at that time, due to our inability to secure a contractor to conduct the operation. We plan to conduct this operation during the early fall or winter of 1996. Work may begin as soon as September 15 if river-flow conditions are conducive. It is our understanding from discussion with Mr. Price that the November 28, 1995, 401 approval is valid under the revised schedule. This letter provides written notification of our revised schedule as requested by Mr. Price. Other aspects of the project are as described in previous correspondence. -2- We would appreciate your written concurrence by August 30, 1996. If additional information is required, please call Mr. Chuck Wilson of our Environmental Resources Section at (910) 251-4746. Sincerely, Lloyd . Saunders; Ph.D. Acting Chief, Planning and Environmental Branch Copy Furnished: ----JMr. John Dorney Division of Environmental Management North Carolina Department of Environment, Health, and Natural Resources 4401 Reedy Creek Road Raleigh, North Carolina 27607-6445 Mr. Steve Mauney Division of Environmental Management North Carolina Department of Environment, Health, and Natural Resources 585 Waughtown Street Winston-Salem, North Carolina 27107-2241 Mr. Franklin T. McBride Wildlife Resources Commission North Carolina Department of Environment, Health, and Natural Resources 512 North Salisbury Street Raleigh, North Carolina 27604-1188 Ik -3- Mr. Joe Mickey Wildlife Resources Commission North Carolina Department of Environment, Health, and Natural Resources 155 Timberbrook Trail State Road, North Carolina 28676 Mr. Jim Meed Division of Water Resources North Carolina Department of Environment, Health, and Natural Resources Post Office Box 27687 Raleigh, North Carolina 27611-7687 State 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 APPROVAL of 401 Water Quality Certification Mr. William Dawson, Chief Engineering and Planning Division U.S. Army Corps of Engineers P.O. Box 1890 Wilmington, N.C. 28402-1890 Dear Mr. Dawson QF C) FE ["%A F1 November 28, 1995 Wilkes County DEM Project # 951229 FILE Coil'' You have our approval to place temporary fill material in waters for the purpose checking the structural integrity of the stilling basins at Kerr Scott Lake, as you described in your application dated 23 October 1995. After reviewing your application, we have decided that this fill is covered by General Water Quality Certification Number 2727. This certification allows you to use Nationwide Pennit Number 33 when it is issued by the Corps of Engineers. This approval is only valid for the purpose and design that you described in your application. If you change your project, you must notify us and you may be required to send us a new application. For this approval to be valid, you must follow the conditions listed in the attached certification. In addition, you should get any other federal, state or local permits before you go ahead with your project. If you do not accept any of the conditions of this certification, you may ask for an adjudicatory hearing. You must act within 60 days of the date that you receive this letter. To ask for a hearing, send a written petition which conforms to Chapter 150B of the North Carolina General Statutes to the Office of Administrative Hearings, P.O. Box 27447, Raleigh, N.C. 27611-7447. This certification and its conditions are final and binding unless you ask for a hearing. This letter completes the review of the Division of Environmental Management under Section 401 of the Clean Water Act. If you have any questions, please telephone John Domey at 919-733-1786. Attachment cc: Wilmington District Corps of Engineers Winston-Salem DEM Regional Office Mr. John Domey Central Files Chuck Wilson; COE Wilmington sin ly, to4nnoo 4rr,, r. P 951229.1tr P.O. Box 29535, Raleigh, North Carolina 27626-0535 Telephone 919-733-7015 FAX 919-733-2496 An Equal Opportunity Affrmative Action Employer 50% recycled/ 10% post-consumer paper DEPARTMENT OF THE ARMY WILMINGTON DISTRICT, CORPS OF ENGINEERS 5W P.O. BOX 1890 .,..,..... WILMINGTON, NORTH CAROLINA 28402-1890 ?•ARe REPLY TO October 23, 1995 ATTENTION OF Environmental Resources Section Mr. Preston Howard, Jr., P.E. Acting Director Division of Environmental Management 0//?4 North Carolina Department of Environment, ti y ? Health, and Natural Resources Jti?F Q & Post Office Box 29535 Raleigh, North Carolina 27626-0535 '`Co Dear Mr. Howard: This letter is in regard to proposed structural inspections of the stilling basin at W. Kerr Scott Dam and Reservoir. The W. Kerr Scott Dam and Reservoir on the Yadkin River is a U.S. Army Corps of Engineers project placed in operation on June 1, 1963. The stilling basin feature of the dam outlet works is a reinforced concrete U-shaped structure about 129 feet long, extending from about a 12-foot width at the outlet conduit to about 55 feet at the downstream end sill. The structure has 11 concrete baffle blocks on the basin floor. Periodic structural inspection is required to assure the integrity of the structure. The stilling basin was last inspected in 1987 by divers without dewatering. However, the proposed inspection will require a dewatered condition to verify previous findings and to determine the extent, if any, of increased deterioration. The inspection contractor will install a coffering system and dewater the stilling basin using pumps. The Yadkin River is the principal source of water for several businesses and towns downstream and sustains fisheries habitat. Therefore, the time allotted for closing the gates, dewatering, and inspection is critical. Reservoir releases through the stilling basin will be interrupted for no more than 12 hours. This period includes a 1 1/2-hour allotment for the inspection. During these 12 hours, the Contractor must set his coffering, dewater, maintain a dry inspection area, and remove the coffering and dewatering system after completion of the inspection. The dewatering operations will be conducted between October 31 and December 31, 1995. The Contractor will be given a 3-day notification prior to the date the dewatering operations are to occur. A Scope of Work that describes the proposed action is enclosed. Printed on ® Recycled Paper -2- Your general water quality certification pursuant to Nationwide Permit No. 33 authorizes discharges of fill material for temporary construction including cofferdams and dewatering in navigable waters of the United States. We have discussed this proposal with Mr. Steve Mauney of your Winston-Salem Field Office, Mr. Joe Mickey of the North Carolina Wildlife Resources Commission (NCWRC), and Mr. Jim Meed of the North Carolina Division of Water Resources. Their comments and standard permit conditions were considered in the development of the proposed plan. We have determined that impacts from this action are temporary and minor and propose to proceed upon your written concurrence. We will notify your office, the NCWRC, potentially affected major water users, and downstream industry prior to commencement of work. Flow and temperature conditions favorable for the completion of this work with minimal environmental impacts are expected during November through December. We would, therefore, like to have clearance to proceed by October 30, 1995. If additional information is required, please call Mr. Chuck Wilson of our Environmental Resources Section at (910) 251-4746. Sincerely, William R. Dawson, P.E. Chief, Engineering and Planning Division Enclosure ??Copies Furnished: VMr. John Dorney Division of Environmental Management North Carolina Department of Environment, Health, and Natural Resources 4401 Reedy Creek Road Raleigh, North Carolina 27607-6445 Mr. Steve Mauney Division of Environmental Management North Carolina Department of Environment, Health, and Natural Resources 585 Waughtown Street Winston-Salem, North Carolina 27107-2241 -3- Mr. Franklin T. McBride Wildlife Resources Commission North Carolina Department of Environment, Health, and Natural Resources 512 North Salisbury Street Raleigh, North Carolina 27604-1188 Mr. Joe Mickey Wildlife Resources Commission North Carolina Department of Environment, Health, and Natural Resources 155 Timberbrook Trail State Road, North Carolina 28676 Mr. Jim Meed Division of Water Resources North Carolina Department of Environment, Health, and Natural Resources Post Office Box 27687 Raleigh, North Carolina 27611-7687 V SCOPE OF WORK DEWATERING STILLING BASIN W. KERR SCOTT DAM AND RESERVOIR WILKES COUNTY, NORTH CAROLINA 1. Background The W. Kerr Scott Dam and Reservoir on the Yadkin River was completed and placed in operation 1 June 1963. The stilling basin feature of the dam outlet works is a reinforced concrete U- shaped structure 129 feet 3-3/4 inches long, extending from 12.25-foot width at the outlet conduit to 54.5 feet at the downstream end sill. The structure has eleven concrete baffle blocks on the basin floor. The average tailwater elevation is 964.5 M.S.L. See Attachment 1 for stilling basin details. The stilling basin was last inspected in 1987 by divers without any attempt to dewater. This time an inspection will be conducted in a dewatered condition to verify previous findings and to determine the extent, if any, of increased deterioration. The Contractor shall furnish all plant, labor and materials and perform all operations in connection with installing a coffering system and dewatering the stilling basin. 2. Coffering System The contractor shall provide a coffering system capable of preventing the tailwater downstream of the end sill from entering the stilling basin. The design of the coffering system shall be the responsibility of the contractor but subject to review by the contracting officer. After completion of the inspection by Government personnel, the coffering system shall be completely removed and disposed of off government property. Care shall :_be_._, taken to avoid any damage to the existing structure but should any occur, repairs shall be made at the Contractor's expense. 3. Dewatering The dewatering system shall be of sufficient size and capacity to pump water from the entire stilling basin to render it in a dry condition for inspection of the concrete floor. A dry condition is achieved when no free water is ponded on the stilling basin floor. Special efforts may be required to control and route leakage flows from the conduit to allow all floor surface areas to be visually inspected without the presence of standing water. However, a portion of the floor may be used to route water if contained at any one time. Leakage of approximately 3 cfs from the intake tower service gates should be anticipated. The design of the dewatering system shall be responsibility of the Contractor but subject to review by the Contracting Officer. 4. Back-up System If, the primary dewatering pumping system fails a back-up system able to perform at 100 percent capacity of the primary system shall be immediately available and placed in operation to satisfy the time constraints once the gates have been closed. 5. Time Constraints The Yadkin River is the principle source of water for several businesses and towns downstream and sustains environmental habitats. Therefore, the time allotted for closing the gates, dewatering, and inspection is critical. Reservoir releases through the stilling basin shall be interrupted for no more than 12 hours. This period includes 1- 1/2 hours allotment for the inspection. During this 12 hours, the Contractor must,set his coffering, dewater, maintain a dry inspection area and remove coffering and dewatering system after completion of the inspection. The dewatering operations will be conducted between 31 October and 31 December, 1995. The Contractor will be given a 3 day notification prior to the date the dewatering operations are to occur. 6. Equipment Access. Access to the work site downstream of the stilling basin is available from the service road on the south side of the stilling basin. 7. Restoration. The work site shall be restored to its original condition after completion of the dewatering and coffering operations. 8. Submittals The Contractor shall submit to the Contracting Officer for review prior to any coffering work, his plan for dewatering. The submittal shall include as a minimum the number, type and capacity of pumps, type and extent of coffering system and safety procedures. 6. Safety Requirements The Corps of Engineers Safety and Health Requirements Manual (EM 385-1-1, October 1992), is applicable to work to be --- performed. Y 0 a Y D ' o O H A4 Y W ? N H } w I r. H ? S V1 s W - w i i' rl H O 1 ••"s ? W f J 'w . ? so Q Z ° co E-4 Y Y ? t CL 80L a = ' w V W 8 8 8 e £ ¦ M i r- • ? I 10I 0 M N Q V Q O Z- in J - v a z o ? c? 0 M6- N H HQ z O U pN O W a 0 c 0 r C" P Y C N W 2 t O N ? o u v ? W 4. N t Occ W II .,l OCT-24-1995 1506 FROM DEHNR Winston-Salem TO 89197339959 P.01 P. 'It North Carolina Department of Environment, Hoalth, and Natural . ftesouroes Division of Environmental Management Water Quality Section Winstorp-Setem Raglorial:Q ae FAX Ile #? of Roo FAX. # - -- - - - FROM: 4U ,.., j?r -<C/--5- 7Oy15- rr.-r NOTE: te Terry IAVI (4 7`000 7//!?? M lbi owm ft "L w mews awn. NC 27147.2119 OW771.46W 0 FAX 010-771-MI OCT-24-1995 15:06 FROM DEHNR Winston-Salem TO DEPARTMENT +OP,TNE ARMY WaimNCiT" UNKR OT, calm OF moomem RO. WX is" WILMINOTON, NORTH CA"XJM 204W-"00 G)ATnWr=QF October 2a,:.1995 Environmental Resources Section Mr. Preston Howard, Jr., P.E. Acting Director Division of Environmental Management North Carolina Department of Environment, Health, and Natural Resources Post Office Box 29535 Raleigh, North Carolina 27626-0535 Dear Mr. Howard: 89197339959 P.02 REGENED N.G. Dept. of EHN91 O CT 2 It 1995 Winston-Salem Regional OT(im This letter is in regard to proposed structural inspections of the stilling basin at W. Kerr Scott Dam and Reservoir. The W. Kerr Scott Dam and Reservoir on the Yadkin River is a U.S. Army Corps of Engineers project placed in operation on June 1, 1963. The stilling basin feature of the dam outlet works is a reinforced concrete U-shaped structure about 129 feet long, extending from about a 12-foot width at the outlet conduit to about 55 feet at the downstream end sill. The structure has 1.1 concrete baffle blocks on the basin floor. Periodic structural inspection. is required to assure the integrity of the structure. The stilling basin was last inspected in .1987 by divers without dewatering. However, the proposed inspection will require a dewatered condition to verify previous findings and to determine the extent, if any, of increased deterioration. The inspection contractor will install a coffering system and dewater the stilling basin using pumps. The Yadkin River is the principal source of water for several businesses and towns downstream and sustains fisheries habitat. Therefore, the time allotted for cloning the gates, dewatering, and inspection is critical. Reservoir releasas through the stilling basin will be interrupted for no more than 12 hours. This period includes.a 1 1/2-hour allotment for the inspection. During these 12 hours, the contractor must set his coffering, dewater, maintain a dry inspection area, and remove the cof6 ring and dewatering system after completion of the inspection. The dewatering operations will be conducted between October 31 and December 31, 1995, The Contractor will be given a 3-day notification prior to the date the dewatering operations are.to occur. A Scope of Work that describes the proposed action is enclosed. pnrrod on MeyeMe paper OCT-24-1995 15:07 FROM DEHNR Winston-Salem TO 89197339959 P.03 w -Z-' Your general water quality certification pursuant to Nationwide Permit No. 33 authorizes. discharges. of fill A tt$rial for temporary construction including cofferdatis.and dewatiririg in navigable waters of the United States. We have discussed thi.s pproposal with Mr. Steve Mauney of your-Winston-Salem Field Office, Mr. Joe Mickey of the North Carolina Wildlife Resources Commission (NCWRC), and Mr. Jim Meed of the North. Carolina Division of Water Resources. Their comments and stahdard permit conditions were considered in the development of thal.proposed plan. We h6*9 determined that impacts from this action are temporary and minor and propose to proceed upon your written concurrence. We will notify your office, the NCWRC, potentially affected major water users, and downstream industry prior to commencement of work. Flow and temperature conditions favorable for the dom letion of this Work with minimal environmental impacts are eXpeCted during November through December. We would, therefore, like to have clearance to proceed by October 30, 1996. If additional information is required, please cal.lAr. Chuck Wilson of dVr Environmental. Resources Section at (910) 251-4746. Sincerely, William R. Dawson, P:E. Chief, Engineering and. Planning Divi$iDn Enclosure Copies Furnished. Mr. John Dorney Division of Environmental Management- North Carolina Department of EnvironM.eot, Health, and Natural Resources 4401 Reedy Creek Road Raleigh, North Carolina 27607-6445 Ar. Steve Mauney Division of Environmental Management North Carolina Department of Envirdoment, Health, and Natural Resources 585 Waughtown Street Winston-Salem, North Carolina 27107-2241 . 11 OCT-24-1995 15:07 FROM DEHNR Winston-Salem TO • Y -3-. Mr. Franklin T. McBride Wildlife Resources Commission North Carolina Department of Environment, Health, and Natural Resources 512 North Salisbury Street Raleigh, North Carolina 27604-1188 Mr. Joe Mickey Wildlife Resources Commission North Carolina Department of Environment, Health, and Natural Resources 155 Timberbrook Trail State Road, North Carolina 28676 Mr. Jim Meed Division of Water Resources North Carolina Department of Environment, Health, and Natural Resources Post Office Box 27687 Raleigh, North Carolina 27611-7687 89197339959 P.04 OCT-24-1995 1508 FROM DEHNR Winston-Salem 4 TO 89197339959 P.05 ?? : bF` •.?OlZK bEPTATERI2Qt3 BTILLZ?iG ]?1N W. K=M SCOT'1,' 1DAR AND R>9'us$l in . WXUES COV"Y,. 'NO'RTH CAROLINA. i . llar?kc?r±outid The W. Karr Scott Dam and Reservoir on the Yadkin River vats completad and placed in operation I' June 1963. The stilling basin feature of the dam outlet works is a reinforced concrete U- Shaped structure 129 feet 33/4 inches long, extending from 12.25-foot width at the outlet ooriduit to $4.5 feet at the downstream and sill. The structure has eleven ooncrete baffle blocks on the. basin floor. The aVokagge tailwater elevation is 964.5 M:S.L. See Attachment 1 for stilling basin details. The stilling basin was last inspected, in 1987 by divers without any attempt to dewater. This time an inspection Will be conducted in a dawatered condition to verify previouis..findinngqs and to determine the extent, if any., of increased deterioration. The Contractor shall furnish all plant, labor and materials and perform all operations in connection with installing a coffering system and dewateri,ng the stilling basin. 2. C_Q=eri._ .System The Contractor Shall provide 'd ,coffering systdm .capable .of preventing the. tailwdter downstreaim of the end gill from entgring the stillirntqq bas:i.n. The design of .the cOffering system shall -bb the responsibility of the aontractor but Oubiact to xevLei v by the Contracting Officer. After eoWletion of the inspection by ; ;:.. Goverrnpent personnel, the cOffer3 g.systet shall he completely rem0'Vlsd and disposed of off gov merit prpperty, ca R .8h?1. taken to avoid any damage to the: :existing :structure . but should dik,Y OCCUr, repairs shall b,& leads' ' at the Coxstraato ? a ? ;;experie8 :;; ? : ` `; 3 • 1Q '3'; • =.= The dewatering system xhal1..lee of suiticient 8*** . and capacity to pump water from the entire. stilling basin :to retzder it in adry condition for inspection of the conerata`flaor.° A -.- dry *Ondition is achieved when no free water is ponded on the stilling basin floor. Special efforts may. be rwPired, to control. and route leakage flows from.the 'cc Muit to allow . all, floor surface areas to be visually,inspeot6d without the Swesence of standing water,. However, a portiaiiof the: floor may be used to route. water it contained at any one time. Leakage 6f apptdXL* ably 3 cis from the iri c® .tearer .s®icvice`gate sh+ou3d?be - anticipated. The design of the de"texing' system nllall be responsibility of the contr&otor but subjt0t to roview by the Contracting Officer. n w OCT-24-1995 1508 FROM DEHNR Winston-Salem rw TO 89197339959 P.06 4. Aack-ub System If, the primary dewatering. pumping system fails.'a back-up syGtem able to perform at 100 .percent capacity of. the primary eyst:em shall be immediately..available and plaaed0' operation to satisfy the time constraints 0400 the gates have' .bean closed. 5- Time ConstzAints The Yadkin River is the principle source of water for several busi.nesseei and towns downstream and sustairw environmental habitats. Tharefoiti,,:the time allotted for closing the gates, dewatering, and inspection is critical. Reservoir releases through the stilling basin shall be interrupted for no more than 12-hours. This period includes x- 1/2 hours allotment for the inspection. During this 3.2 hours, the Contractor nuat\ eot his ootiering, devater, nai .gain at dry inspection area 'and remove coffering and davaterinq ayateoaa aftex completion of the inspection: The dewat6ring operations gill be conducted betioeen 31 October and 32, December, 1995.. The Contractor will be given a 3 day notification prior to the..date :the dewatering _dperat.ions -axe , to occur. 6- AM3i8 cae$a. ACKMBN to the cork site dM mat r6am of the st'Ill1ng basin in available from. the service road : on the mouth side of.:trhe. j LIX3r basin. The work mite, si ll 'be -V,60 to its after letion of t h ._degi - "? - :-?-' comp .at?'_Oiifl cof'feriny cpaiAtii-s.?,-:;,;?;,;?•: NMi w4Y?M• The Contractor shall submit ,:tab. +.he coht Tact uu g •. oft. dIke fur .?? -- review prior to any cofferin4''iroi ,, `.hi a plan for submittal shall include as -. a -the nwiber, t capacity of ptamps, type and *Xtant of coffering. s !s?:-and -slltety procedures.. .. 6. K41--sty _KWUirement:9 The Corps-of Engineers Safety ."d Health Requirem"Ito Manual 385-1-1, October 1992), Is appyi;,oable to work to be OCT-24-1995 15109 FRO M DEHNR Winston-Salem TO 89197339959 P.07 pp S1 ` . TOTAL P.07