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Exh 8GAGENDA ITEM NO.~ '~ DATE. JZ.' I -~ ~' g CITY OF ATLANTIC BEACH CTTY COMMISSION MEETING STAFF REPORT AGENDA ITEM: Wonderwood Utility Relocation -Change Order SUBMITTED BY: Robert S. Kosoy, P.E., Director of Public Works DATE: December 3, 1999 BACKGROUND: On November 10, 1999, we received a letter from George Mayforth, Jr., Project Engineer for the Wonderwood Connector Project, stating Superior Construction Company notified them that JEA is now requiring the use of a higher quality air release valve for the project. We contacted Frank Gray, P.E. of The R-A-M Professional Group (R-A-M), the City's design engineer for the project, to ask his recommendation for specifying the superior valves {Vent O Mat air release valves) at the eleven locations air release valves are shown on our portion of the project. Mr. Gray responded to our inquiry on November 24, 1999, and recommended we use the Vent O Mat valves at four locations. Because of the higher quality and ease of maintenance of the Vent O Mat valves, he recommended they be used at two locations on the bridge, where the relative inaccessibility of the valves would make maintenance difficult, and at the ends of the two force mains for improved protection against pressure surges. The original air release valves had a unit cost of $895. Superior Construction Company has agreed to honor their unit price of $4,500 for the Vent O Mat valves if Atlantic Beach requests use of these valves on our force mains. The cost difference for replacing four of the air release valves will be $14,420. BI'L1GET: Funds are included under the Buccaneer Sewer Utility Fund Capital Account No. 410-4401-535-b300 in the amount of $57%,000. Currently the constnlction is estimated at $550,000. RECOMMENDATION: Approve a Change Order in the amount of $14,420 to provide Vent O Mat valves in lieu of the standard air release valves at four locations for the Wonderwood Utility Relocation Project. ATTACHMENTS: 1. Letter from George Mayforth, Jr. dated 11/10/99 2. Letter from Frank Gray, Jr., P.E. dated 11/24/99 3. Information on Vent O Mat valves 8 pages) REVIEWED BY CITY MANAGER: T/ ~L° ~ u Wonderwood Connector -Segment 2A Construction Management Services by Reynolds, Smith & Hills CS, Inc. .. . November 10, 1999 Mr. Robert Kosoy, P.E. Letter No.: CO AB-002 Director of Public Works City of Atlantic Beach 1200 Sandpiper Lane Atlantic Beach, FL 32233-4381 Subject: Wonderwood Connector -Segment 2A State Project No.: 72000-3576 Air Release Valves Dear Bob: Please refer to Superior Construction's October 26, 1999, letter (copy attached) in which they state that JEA is now requiring the use of the Vent 0 Mat air release valve, and that this is a change to the contract. In their letter they state that their proposed unit price of $4,500.00 will be honored, should the City of Atlantic Beach also request that this valve be used on their force mains. Please review the contractor's letter, and advise me in writing if you wish to pursue this or a similar change to your s st I have reviewed the contract pay item list, and it appears that this is related to your Pay It 070-118-105 Release Assembly (F&I) (1034 K PA) (SOmrr~) with a plan quantity of 10 and a unit price of .00.~ ~~o-t~8--©S Should you determine that this modification is unnecessary, a telephone call to advise me of your intentions would be adequate and most appreciated. Q ~ ~~olace w/ Sincerely, ~ ~~ ~` /c.•~'b+n~ ;~~e n /3'~!-~' oA~ ~~~~~~ ~, g 1 / ~ ~ ~ ~~~ z g ~~ 1`2'~George F. Mayforth, Jr. D 3 Project Engineer GFM/LPW:jj O:~Enginej enU,azryllcosoy. doc Attachment -SCC letter dated 10/26/99 ~y cc: L. Wehner, JTA Pete Kelley, SCC CM File 102.6 PCO No. 19 ~O~1~J~ ~ 99 THE R-A-M PROFESSIONAL GROUP, INC. ENGINEERING -PLANNING -ENVIRONMENTAL CONSULTANTS ~.- November 24, 1999 f!( t ,1 ~ r' ,, y Mr. Robert S. Kosoy, P.E. '~~` Director of Public Works ~. City of Atlantic Beach 1200 Sandpiper Lane Atlantic Beach, Florida 32233 Re: Wonderwood Segment 2A Ventomat Air Release Valves R-A-M Project No. 198-023-04 Dear Mr. Kosoy: Via Facsimile: 247-5843 We have completed our review of the air release valve locations for the referenced project and have the following recommendations: Use the Ventomat air release valves at Station 283+96 (on 150mm force main) and Station 299+00 (on 300 mm effluent main) for surge purposes. Use the Ventomat air release valves at Station 288+51 (on 200 mm permanent force main) and Station 288+50 (on 300 mm effluent main) for maintenance purposes. In our opinion the long-term benefit at these locations is worth the additional front-end expense, but at the rest of the air valve locations the expense is probably not warranted. If you have any questions, please advise. Best personal regards, THE R-A-M PROFESSI AL GROUP, lNC. ~~ , Frank E, Gray, Jr., P.E. Principal and Director of Engineering FEG:Imj 8298 Bayberry Road, Suite 1 -Jacksonville, Florida 3ZZ56 (904) 73 1 -5440 -FAX (904 73 1 -5465 12-87-0099 09~58AM FROM R-A-M PROFESSIONAL GROUP TO YENT•0-, 2475843 P.01 Fax Note 7671 Post-tt' °~s ,~ 'f D4pe8~ g /f 70 ~bb pSO From ~.,.,,yr Co-lDep-• ~c~.rtG Co, ` rf " nv1 /' ~ , _ l y phone ~ 9rO ~'/' S0 xi a , ~-y~_,,{~ phone ~ 73 1 ~ 7'~'"`~~ FAX # gl~ 2 / -~ ~$ ~ ~ j Fdx # C~j /.3~ + ~ S SERVES RGX "ANIT-SURGE" SEWAGE AIR RELEASE ANA YAGUUM BREAK VALVES A iJruque Operating Concept Proven Unsurpassed for Sewage Aur Release Air release and vacuum break valves are prescirted with major functional problems when operating on sewage and effluent pipelizres transporting solids and other viscous substances- In fact solids, fats and oils quickly act to jars up standard air release valves and reztder them useless, consequently leaks threaten health and the ecv system. The Yent-O-Mat series RGX sewage air release and vacuum break valve has evolved from a long lineage of research and development, resulting in a unique operating concept that has proven unsurpassed. The series RGX valve does not require flushuig with clean water to remove internal. blockages - flushiztg connections are therefore completely absent from this design -this combined with the corrosion free stainless steel and HDPE materials of construction means virtually no maintenance. Tote valve in addition to acting as a very efficient double acting air valve, automatically protects the pipeline against surge pressures due to puzz~p trip, resulting in total pipeline protection. Advantages of Vent Or.Mat "Anti-Surge" Sewage Air Release & Vacuu~pa Breal~ Valves Are: + "Anti Surge": lvlechanism: An integral mechanism which automatically dampens out surge and water harnxaer due tv high velocity air discharge, celusnn separation and liquid oscillation, obviating the need for expensive, conventional surge equipment. • Reduce~3 operations! procedures: ~'illitrg and draining times are substantially reduced as the valves have large orifice diameters equal to the nominal size of the valve allowing for the maximum possible intake or discharge of air. . Savings in maintenance costs: -RGX valves effectively protect against destructive phenomena such as surge, water hammer and vacuum etc., substantially reducing maintenance requirements. + Performazece:The RGX has been developed to provide the optimum usable and safe performance relative to all functions. Selection data has been substantiated through Council of Scientific and Industrial Research and other testing and can therefore be confidently referenced. http://www.ventomat.com/ventom4.htm 1.2/7/1999 12-0?-0099 09~59AM FROM R-R-M PROFESSIONAL GROUP TO ~N7'oMA~ sus RGx 2475843 P.02 Page 2 of 2 Vent-o-Mat series RGX Sewage Air Release and Vacuum Break Valves are available in nominal sizes of DN50(2") to DN204 (8"}and for a maximum operating pressure of PN10. Valves for higher pressure ratings are available vn request. r [lletailed_ Cataloguel [ YEN'TOMAT Home Pa Revised Jan '97 tzrip://www.ventotnat.com/vemtoar4.hnn 12J7/1999 TOTAL P.02 ~HF.AU>Series RGX Operation~,A,D> Series RGX OPERATION PRE NOTES; A,).-~NTING OF A FILLING PII'E~.~1E: Page 1 of 2 The ope~tation of a conventxottal sewage air release valve is such that fast approaching sewagelef~luent is almost instantaneously halted by the valve's closure. Consequently surge pressures of potentially damaging proportions cart. be generated in a pipeline system, even at normal filling rates. In addition to venting tl~rotigln the Large Orifice when sewage /effluent approach velocities are sub critical, the Vent -O-Mat series RGX sewage air release valves feature an automatic "Anti -Surge" Orifice device that serves to decelerate sewage /effluent approaching at excessive speed, thereby limiting pressure rise in the pipeline. B). SURGE ALLEVIATION -PIPELINE PRESSURIZED: ba instances where a pipeline experiences liquid column separation due to pomp stoppage, hagla surge pressures can be generated when the separated column rejoins. The Vent -O- Mat series RGX takes in air through the unobstructed large orifice when coluztzzt separation occurs, but controls the discharge of air/gas through tk~e '',Artti~Surge" Orifice as the separated column comrr~ertces to rejoin. The rejoining impact velocity is thereby sufficiently reduced to prevent an. unacceptably high surge pressure in the system. In the same way the series RGX valve prevents high stage pressures resulting from liquid oscillation in a pipeline. 1. PIPET.,~IE FR..I,ING (SUB CRITICAL SEWAGE/EFFLUENT A,~'PR,OA-CI~E VELOCITY) Air/gas flows through the annular area around the cotrtrol float assembly and to atanosphere through the large orifice. 2. PII'ELINE FILLING EXCESSIVE SE~'A,GE/ EFFLUENT APPROA~CR VELOCI'T'Y} In reaction to an increase in air/gas flow, the ".Anti -Surge" float closes the large orifice and air/gas is forced through the "Anti -Surge" Orifice resulting in a deceleration of the approaching liquid due to the resistanve of rising air/gas pressure in the valve. Attention is drawn to Pre Notes (A) and (B) above. 3. PIPELINE FULTt.,Y CIiARGED Sewage/effluent has entexed the the valve chamber and buoyed the floats to eiose both the large and http://r~~vvw.vemomat.com/rgxlrgx3.htm 1,217!2 999 12-07-0099 10~01AM FROM R-A-M PRQFESSIONAL GRQUP Tp 2475843 P.02 • the small orifice. The desigt's compression! volume relationship pneveztts the media from ever exceeding the maximum sure Level indicated in diagram 3. T h e resultant sewage! effluent free arce protects against the fouling of ttte orifice seals by solids or bxgh viscous substances -for this reason NO FI.1JSHlNG CONNF,CTIONS AlZE NECESSARY. 4. PRESStIR,~ED AIRJ GAS ~;I,EASE -PIPELINE UPERA3TNG The ~vo[ume of dise~n-brairxed air/gas increases in the valve and dxspla,c~s the sewage%ffluent to the lower, normal uperating level (small orifice cvmrol boat buoyancy level). Any additional lowering +~f the sew•atrJeiF[utnt level, as wattld occ~zr whezt more airlgas enters the valve, will result in the contra! float dropping away from the small orifice thmugh which pressurised air/gas is then being discharged to atmosphere- The control float will claw the stn.all orifice when sufi'icient air/gas has been relea~d to rest~ore.the sewage effluent to the nvrmai operating Ievel. The considerable sewageleflluem free area obviates the possa~bility of leaks that coiild otherwise be caused by solids entering the sealing areas - far this reasonNO FLUSHING ~COiV'NEC'I`IONS A1tE NECESSARY. 5. VACUUM ~t.EI,IEF (Alit. IN7',A~E) - PIP`EL~NE DRAINING when the internal piipeline pressure reduces to atmosphere the "An~ri • Surge" meohazuism and control float assernbl.y drops, opens fire large orifice and allows the pipeline ra take in air tb displace the draining media so as to prevent undesirable low ncgativ+e pressure'`. Thu hollow, smooth side float design discourages adherence of solids and.viscous substances which, thez~efoxe, tend to withdraw from the valve into the pipeline when draining occurs - for this rE:asvuNO. FI,>(ISITYNG CONNF,CI'IONS ARC NECESSARY. *NO'Il~;: Negative pressure values aze dependarrt on valve size selection. Dien Revised Jan'97 http://~vuw.v~ntomat.comlrgac/rg~c3.htm 12!7/1 X39 12-07-0099 10~02AM FROM R-A-M PROFESSIONAL GROUP TO 2475843 P.03 .. -.a- ..... . Series ItG~ GENERAL SPEC~FiCAT~ONS FLANGED - DN50 (2 "}TO DN200 (8 "} Tyke: Double Orifice {Small & barge Orrice) with Anti Sorge Orifice '~ Mechanism. End Couneciion: Flange with Screwed Studs for Alignment to: BS 4504 l'N 10 SAGS 1123 -Table 1000/3 ANSI B l b. l Class I25. Nominal Sizes: DN50 (2"), DN80 (3"), DNI00 (4"}, DN150 (6"} & DN200 (8") Model No's: Pressure Ratings bar (psi} GX I001 & I02~ PN IO 150 psi) ANSI # 1251 O ratio pressure Ran a -bar si ~- 10 (150 psi) ANSI #12~ 0.5 {7.2)~ 10 (154 Function Standard Factory Tests: i. High volume air/$as discharge - ~ipelioe filling. ii. High volume air intake -pipeline draining. iii. Pt~essurized air/gas discharge -pipeline filled. iv. Surge dampening -high velocity air/gas discharge, liquid coiumrt separation & liquid oscillation. i. Hydrostatic test - 2 x mAx. rated working pressure ii. Low head leak test - 0,5 bar (7.2 psi) iii. Small orifice function. test at max, xated working pressure (minirnuzn 1 valve in 10). ~Val.ve Selection ~M_a_teriais of Construction DN50 to T?N1001 Materials o_f Construction DN150 & DN200i Clnstallation Overall Dimer~sians and Weights Revised Jaa '97 http://~vww.ventomat.corn/rgx/rgx5.htm l 2/7II999 12-07-0099 10~02AM FROM R-A-M PROFESSIONAL GROUP TO 2475843 P.04 ... _ . . Series IiGX COMPONEN'T' DESCRIPTION & MATERIAL SPEC~'ICATION FLANGED - DNSO (2") TO DNl t)0 (4") 'h'ype: Eud Commection: Series RGX -Double Urif~ce (Sma1I & Large. Flazzge with Screwed Studs Orifice) DN50 (2") valves available screwed BSP/NPT -wale with "Anti-Surge" Mechanism orz request Nominal Sizes: DNSO (2") DN80 (3 ") DN100 (4") 1v~odel Na's: Pressure Ratings; RGX 1001 & 1021 PN10 (150 psi) ANSI #125 http://www.venttomat.com/rgx/r$x6.htm 12/7/1999 12-07-0099 10~02AM FROM R-A-M PROFESSIONAL GROUP TO 2475843' P.05 . maten~ua ~i w~wuu.,µ.,u Top Flshge 8 SYed AtS130~ 5cresrt 1Aesb Stainless Steel A1513D+4 l 1 ~ t3otts Stedr'dasa Steil atS130a huts S'{ ~~ Anti S~uoc pia Fto Top Mont otyemmY~e Co~tilKl Screws Cheraehead Stainless Steel 30Q ~Fi,ANGID - DN150 (6") TO DN200 f 8")1 Revised Jan'97 http:!lwww.ventomat. comhrgxlrgx6.htm lop Carer unless Steil AI51304 14eeembt;t Sorvws ~- Cheeset~ead STainfe$s SRlxl AfS1304 ~""-~ Spa+ser Grey P.V.C. Q - »~ Seai NRrtle Ruth' ""~ 0 - Rinp 5tst NdrAe Rubber Corueesti~ lE~scicet Stainless Steel A1St 304 de Seat tag Plate Stainless Steil ~I5~ ~4 Hczziie Stairdr„is Stet! AtS! 3634 Nozrte Seat htatu~l Rubber ~~ Stainless Steel ~4 L.vW'Cr Fioet High Densty Pvlyettr~iex~e ~~ Stainless mod AiSi ?A4(. 12/7/1999 TOTAL P.05 12-07-0099 10~00AM FROM R-A-M PROFESSIONAL GROUP TO 2475843 P.01 -ate ,.... . Series RGX 4PERATIUI~T SuryP' ~ l~ F'R~£IJNE FiLLiN6 PIPE1lf~E Fttl.Ht[~ [~ CRl1'iCA1 SEYA~ f ~FFittEiµT [E}CCE381iYF S~lIA1t?~ f EFtLU~1T At~ACH YEYOCtnI Pif~PRQR~}i YEtopTYj Norn-a} ODerstiny Leeet (S+n~ CktHoe Control Floes @auyanq Lctret) 70 bar (~O psi j u~xkir-y Pressure ~~~ P~ AIR / GAS R~t.t:A~ P OI~tl1Z7lIG [Pre-Notes Revised Jan '97 ~~ PiPE1.N1~ Fi1LLY CMARt~'A VACUUM RELJEF LAIR 111'I'AISE) PFP>:L1lE DRAG http://www.ventozt~a~.com/rg~zgx2.htm ] 2/7/1999