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HomeMy WebLinkAboutDocumentation_Regular_Tab 9K_2/11/1993 • r' Mt gri VILLAGE OF TE UESTA �� � ""; Q s Fte ar,� ,fit • �'`�t WATER DEPARTMENT Og 1 1•:��� Ak? Post Office Box 3474 • 357 Tequesta Drive �q��[A�E 99 , t�",o'0 4 Tequesta, Florida 33469-0474 • (407) 575-6230 L.\R �F<eh, • MEMORANDUM /7`J'�i- �a TO : Thomas G. Bradford, Village Manager FROM : Thomas C. Hall, Water System Manager +�f DATE : January 25, 1993 SUBJECT : Well Rehabilitation/Redevelopment In this year' s Operation and Maintenance budget for the Water Department, we have allocated $30, 000 for routine well redevelopment. Our target goal has been to service three wells per year. This, of course, depends upon water demand, weather and mechanical conditions. Our present schedule calls for redevelopment of Wells 7 and • 23. With current weather conditions as they are, (unseasonably wet) , we would like to have these two wells serviced concurrently, thereby realizing significant cost savings in mobilization charges. Well ,7 has recently experienced mechanical failure and is out of service which necessitates repairs as soon as possible. Specifications and requests for quotes were submitted to Layne-Atlantic, All Webb' s Enterprises and A.M.P.S. Their bid quotes are attached. These firms have the expertise and equipment available to service municipal installations and are also used by the Town of Jupiter. Layne-Atlantic .has submitted the lowest quote in the amount of • $12,420.00. I recommend they be awarded this work. Please place this item on the Council Agenda of February 11, 1993 for recommendation of award. Upon their approval, a purchase order will be issued so that we may begin as soon as possible with this vital project. . • TCH/mk Attachments • c: Roy Fallon, Chief Operator • WELLS3 VILLAGE OF TEQUESTA WATER DEPARTMENT February 1993 BID QUOTES FOR WELL REDEVELOPMENT VENDOR ADDRESS QUOTE ALL WEBBS ENTERPRISES 309 COMMERCE WAY $14,500.00 JUP ITER, FL. 33458 LAYNE—ATLANTIC CO. 1107 S. ORANGE BLOSSOM TR. ** O RLAN DO, FL. 32805 $12,420.00 AMPS 877NW61stST FT. LAUDERDALE, FL. 33308 $15,082.00 Note: Pump repair parts (rf required) are not included. ** Staff recommendation. All Webb's Ent: O'rises, Inc. 309 COMME WAY JUPITER,FLO"Pi 33458 PHONE(407)',;!I:-2079 FAX(407)74;44199 February 4, 1993 Attn: Tom Hall Village of Tequesta Water Department P.O. Box 3474 Tequesta, FL. 33469 Dear Mr. Hall , Please find enclosed the proposal for redevelopment of well num- ber 7 and 23. As per Specifications dated Febuary 2, 1992 pages 1 thru 10. MOBILIZATION WELL NO. 7 WELLHEAD MODIFICATIONS SPECIFIC - CAPACITY, SAND CONCENTRATION MEASUREMENTS CHEMICAL TREATMENT PROCESS (SAFETY• REGULATIONS) SHOCK CHLORINATION ACID TREATMENT SHOCK CHLORINATION SPECIFIC CAPACITY TEST VIDEO CLEAN AND RESET PUMP $7,600.00 WELL NO. 23 WELL HEAD MODIFICATION SPECIFIC - CAPACITY TEST CHEMICAL TREATMENT PROCESS SHOCK CHLORINATION ACID TREATMENT SHOCK CHLORINATION SPECIFIC CAPACITY TEST CLEAN AND RESET PUMP $6,900.00 TOTAL $14,500.00 If you have any questions regarding this proposal , please do not hesitate to call me. David W. Webb, President r • QUOTATION 8 ne lajnejklantk Compang A bMslon of Layne-Western Company,Inc. 1107 S.Orange Blossom Troll • Orlando,Florida HBO • Phone:4071423.7837 • Pax:407/843•esa7 PROFESSIONAL SERVICES FOR WATER SYSTEMS WATER WELLS • LAYNE PUMPS • TEST bRILLINO • WATER TREATMENT EQUIPMENT • To: Village of Tequesta Date 4174:/93 • 357 Tequesta Drive Tequesta, FL 33469-0273 Quotation No. VT45298R-REV. • Attn: Thomas Hall Reference: Rehabilitate Well #7 and well #23 • • DESCRIPTION PRICE • Rehabilitate well (each) $ 6,.2a.0.00 Notes: 1) Estimate includes furnishing all labor and materials to perform the above mentioned. 2) Estimate .assumes access to two inch water line close to well site. • 3) Pump repair parts (if required) are not included. 4) The project is estimated to take 4-5 days per well . . 5) Above prices are per well estimates. Net• • 30 Days TOTAL $6,210.00 ea. s _- SHIPMENT: Layne-Atlantic Company SHIPPING DETAILS: • , pO,rb„g a,yrooq,r,�,r y Ina 'ROPOSED START DATE: The foregoing prices are subject to Federal.State and Local Sales C" r Ind Use Texas.This Ouotatbn will automatically expire If Purchaser ' gijf--/Jw/ foes not delver a written acceptance to Contractor by By • i: ‘CCEPTANGE: • The undersigned accepts the above proposal at the prices shown,subject to any necessary revision In the list of estimated quantities,and toreby authorizes and instructs Contractor to proceed with the described work.The undersigned understands and agrees that the Terms and :onditions shown oaths reverse-are hereby Incorporated as part of this contract. aurchaser Address 3y Date .AT 34-1 11/g1 Papa—of . AlPS/AQUIFER MAINTENANCE AND PERFORMANCE SYSTEMS 877 N.W. 61st Street • Fort Lauderdale • Florida 33308 • 305-038-0595 February 2, 1993 \ VILLAGE OF TEQUESTA Water Department P.O. Box 3474 Tequesta Drive Tequesta, FL. 33469-0474 Attn: Tom Hall Re: WELL REHABILITATION (#7 & #23) Dear Mr. Hall , AMPS Inc. certainly appreciates the opportunity to submit the following prices for your review and reply. 1 . STEP #1 INCLUDING HEAD MODIFICATION $ 2,760.00 2. STEM #2 COMPLETE $ 9,022.00 3. STEP #3 COMPLETE $ 3,300.00 TOTAL PRICE FOR WELLS #7 & #23 $ 15,082.00 The above prices are complete per specifications with a pretreatment video included at no charge. If you should have any questions, please feel free to call 1-800-734-8599. Sincerely, ','‘$>11-,•j'‘AL Robert Neufer • Vice President • FOR YOUR TOTAL PUMP AND WELL FIELD NEEDS SPECIFICATIONS FOR THE TESTING AND TREATMENT , OF PRODUCTION WELLS FOR THE VILLAGE OF TEQUESTA Physical Dimensions of Production Well 7 AND WELL 23 Based on available data, Production Well '1 was installed in 1980 and is reported to be 60 feet and screened between 45 and 60 feet below grade (bg) . This well is constructed of 8-inch diameter steel casing and screen, and 12-inch diameter steel outer casing. The wells historic operating capacity ranged between 400 and 600 gallons per minute (gpm) . Well 23 was constructed in 1981 and is 60 feet in depth, cased to 45 feet and screened 45-60 feet. Casing diameter is 10 inches and this well operating capacity is 1, 250 gpm. Wellhead Modifications Required for Chemical Treatment The wellhead configuration for each production well may require modification in order to . safely pump chemicals into the well. A schematic of the recommended wellhead configuration is enclosed. Basically, the modification requires the installation of a valved, 2- inch diameter retractable steel chemical feed line (the feed line shall be set to a depth of about 5 feet above the bottom of the well screen (55 feet bg] ) and a valved, 2-inch diameter pressure relief line that will be welded to the 8-inch diameter flange which is bolted to the well head. The existing gravel feed line shall be fitted with a valved, 2-inch diameter steel annulus pressure relief line. A 4-inch diameter pressure gauge, 0 to 50 pounds per square inch (psi), shall be installed on the casing and annulus pressure relief lines. A 2-inch diameter threaded steel plug will be installed in the 8-inch diameter flange after completely removing the retractable chemical feed line. . • The pressure relief lines are designed to prevent excessive pressure build-up in the 8-inch casing and in the annulus between the 12- and 8-inch casings. Both lines will be extended approximately 50 feet from the well and will terminate in a minimum 500 gallon tank of water such that any gaseous product of the chemical treatment will be discharged under water in a completely enclosed environment. All valves, fittings, tanks and temporary discharge pipe are the responsibility of the Contractor. Specific-Capacity Testing and Sand-Concentration Measurements At the request of the' Owner' s representative, prior to removing the existing well pump, a 30-minute specific-capacity test will be conducted on the well to determine its current production capabilities. For this purpose, a manometer and orifice (or a water flow meter) and a means to measure water levels in the well must be provided as well as temporary discharge pipe. Initially, the amperage draws on the existing pump motor will be measured and recorded; the depth of the well and the static water level will be measured to the nearest 0.01 of a foot and recorded. After starting the pump, the flow rate and water level within the well shall be measured and recorded at least every 2.5 minutes over the 30 minute test. The flow rate shall be set as high as possible without damaging the pump. A measure of the sand concentration in the fluids from the well also shall be recorded at least three times during this - 2 - test. The Contractor shall submit his recommended method for determining the sand concentration ( in parts per million) in the fluids from the well to the Owner' s representative for approval prior to the start of testing. An acceptable discharge point for the well fluids will be agreed upon by the Contractor and the Owner's representative. Chemical Treatment Process The Contractor shall provide all personnel involved in the work with all the necessary (Level D) protective clothing (goggles, hard-hat, steel-toe shoes, rubber outer garments) and have available, on site, a source of potable water for emergency use. Only personnel experienced in this type of work shall be employed in the treatment process. Great care should be taken in placing chemicals into a well. The chemical treatment process will consist of three steps; initial shock chlorination followed by acidizing and then ,a final shock chlorination. The chlorine and acid should never be in the well at the same time. Step 1 - Shock Chlorination The Contractor shall shock-chlorinate the well. Prior to the start of this treatment step, the Contractor shall submit details (manufacturer, type and quantities) of - 3 - chlorine proposed for use to the Owner' s representative for approval . This treatment step will consist of the injection of 2000 gallons of 2000 milligrams per liter (mg/L) , (minimum strength) sodium hypochlorite solution into the • well ( and the gravel feed line) . Injection, using the chemical feed line, shall start at the bottom of the well and the feed line raised at 5 foot intervals until the entire well screen and casing below the static water level in the well is filled with the chlorine solution. ' After the chlorine solution has been introduced into the well, it should be forced through the screen slot openings by adding a 100-gallon slug of potable water to the well. Then, mechanical agitation (surging or jetting) of the well (for approximately 2 hours) will be performed to enhance the effectiveness of the procedure and loosen and dislodge the plugging material. The chlorine solution shall remain in the Well a minimum of 12 hours. After 12 hours, a volume of solution equal to the volume of the well bore will be pumped from the well. The Contractor then will measure the chlorine concentration in the well using a chlorine test kit. Fluids shall be discharged from the well until the test kit measurements indicate that chlorine is not present in the well bore. - 4 - Step 2 - Acid Treatment The total volume of acid solution to be added to the well will be 1000 gallons, consisting of a 50-50 mix of 20 degrees Baume hydrochloric (muriatic) acid and potable water, ' incorporating " a ferrous inhibitor and chelating agent. The inhibitor will be approved by the Engineer and applied in a concentration of one-half per 100 gallons of acid. The chelating agent will be citric acid (or approved equal ) in a concentration equivalent to 2 pounds of citric acid per gallon of muriatic acid. The Contractor shall submit his acid treatment program, providing details of the type and quantities of acid and additives to be used, to the Owner' s representative for approval prior to initiating this treatment step. The acid shall be introduced into the well through the 2-inch diameter chemical feed line starting at the bottom of the well and raising this line at 5 foot intervals until the entire well screen and casing below the static eater level in the well is filled with the acid solution. If necessary, injection of acid may be temporarily decreased or terminated in order to prevent excessive build up of gas pressures in the 8-inch casing or in the annulus between the 12- and 8-inch casings. Gas build-up in the well in excess of 10 psi shall be relieved through the pressure relief lines. - 5 - The injection of the treatment solution shall be followed by the addition of a 100 gallon slug of potable water to force the solution through the screen. (Compressed air may be used in lieu of water to force solution through well screen. ) Some form of mechanical agitation, such as surging or jetting, will be employed to help break up the plugging. material and improve the overall efficiency of the process. The well then will be shut-in for a minimum of 8 hours, 24 hours if an acid enhancer is used. All acid injection lines shall be removed from the well prior to shutting in the well. . Prior to pumping off the acid, the contractor shall scrub (about 1 to 2 hours) the inside of the well screen with a steel wire brush to remove any scale or encrustations. The Contractor then shall install a turbine pump in the well to pump the spent acid and the by-products of the treatment process to a point of discharge acceptable to the Village of Tequesta and appropriate regulatory agencies. The pump shall be capable of producing 300 gallons per minute (gpm) continuously and shall be valved so that the capacity of water pumped can be reduced to 50 gpm. The pumping of the by-products of the acid treatment process may be deemed to be complete when the pH of the water pumped from the well reaches background pH readings or above 6.5. Thereafter, the Contractor shall redevelop the well by high capacity pumping and surging until the well is free , and clear of all color, turbidity, sand, and other deleterious matter. At the beginning and end of development, a 30- minute specific capacity test will be conducted to assist in - 6 - evaluating the effectiveness of the developing operation. After the well has been developed to the satisfaction of the Owner' s representative, the shock chlorination procedures described in Step 1 will be repeated. Step 3 - Shock Chlorination The Contractor shall shock chlorinate the well. This treatment step will consist of the injection of 2000 gallons of 2000 milligrams per liter (mg/L), (minimum strength) sodium hypochlorite solution into the well (and the gravel- feed line) . Injection using the chemical feed line shall start at the bottom of the well and the feed line raised at 5-foot intervals until the entire well screen and casing below the static water level in the well is filled with the chlorine solution. After the chlorine solution has been introduced into the well, it should be forced through the screen slot openings by adding a 100-gallon slug of potable water to the well. Then, mechanical agitation (surging or jetting) of the well (for at least 2 hours) will be performed to enhance the effectiveness of the procedure and loosen and dislodge any remaining material. After agitating the well, a volume of solution equal to the volume of the well bore will be pumped from the well. The Contractor then will measure the chlorine concentration in the well using a - 7 - chlorine test kit. Fluids shall be discharged from the well until the test kit measurements indicate that chlorine is not present in the well bore. After the 3 step treatment process has been completed to the satisfaction of the Owner's representative, a video tape of the inside of the well shall be performed to document the integrity of the well construction and the post treatment conditions of the well materials. A copy of the video tape, . completed field logs and notes and specific capacity test results will be sent to the Village of Tequesta for review and confirmation of well conditions and acceptance. The wells submersible pump, column pipe, and all appurtenances removed from the well must be thoroughly cleaned inside and out in an acid bath, rinsed thoroughly with water and allowed to soak in a 2000 mg/L chlorine solution for a minimum of four hours and rinsed with potable water. After that time, the pump and accessories will be installed in the well, after any repairs have been made at the direction of the Owner. For submersible motors, an appropriate length 316 stainless steel safety cable will be attached to the pump column and double clamped to the well head to prevent the loss of the pump down the well. - 8 - Upon completion of all work, the well site shall be cleaned up and left in a neat and orderly condition. The Contractor will notify the Owner' s representative of his impending departure at least 2 hours prior to leaving the site. - 9 -