The URL can be used to link to this page

Home My WebLink AboutTask Order 10238 with Brown and Caldwell for Implementation Plan Study for Microthrix Control,~. .~~~ r { :: PURCHASING AGENT 33 E. Broadway Ave, Meridian, Id 83642 Phone: (208} 489-4417 Fax: (208} 887-4813 TASK ORDER NO. 10238 Between CITY OF MERIDIAN AND BROWN AND CALDWELL This Task Order is issued by City and accepted by the Engineer pursuant to the mutual promises, covenant and conditions contained in the Master Agreement between the above mentioned parties dated April 13, 2014. Implementation Plan Study for Microthrix Control Task Order 10238 SC~,OPEQF,.SE_ RVICES 84!051364.003 Introduction The City of Meridian wastewater treatment plant periodically experiences mixed liquor settleability problems due to the excessive growth of Nlrcrothrrx Parv~cella (MP} in their secondary process. Plant staff controls settleability by reducing the solids retention time (SRT} to less than four days, thereby wasting MP from the process. A total nitrogen (TN}effluent concentration of 15 mglL is required far Class A reuse which is difficult to obtain at this low SRT: The City would like a permanent solution to control MP to enable the plant to operate at higher SRTs and allow TN control. Phase X00 -Project Management Provide management, direction, and coordination of all work associated with this scope, including schedules, budgets, technical quality, deliverables, and invoices. Provide communication and coordination with the City as necessary. Prepare monthly invoices, including backup materials and accompanying status reports. Update construction cost estimate at each design submittal. Provide quality control of all work produced. Deliverables • Meeting minutes as needed Assumptions • None Phase ~~ -Influent Characterizationond Process Review rte, ' al tical Ian to collect data specific to the calibration of a biological Prepare a sampl+ng and any p ' ear will visit the rocess simulator. Verify sampling locations. A Brown and Caldwell process eng+n p h discrete sam lin of mixed liquor effluent from each aeration basin. Review site to scope out t o p g r o, Cnce ata returns from laboratory to ensure integrity of data generated by lobo at ry early d w+ the laborato andlor om late the data set will be reviewed and any anomalies resolved th ry . c p ' al data set will be used in concert with exist+ng process conditions to call ra e plant staff. The fin in to the ' tar. The simulator will be used to assess the environmental conditions lead g the sirnula II rovide rowth of MP and the effect of corrective measures. Brown and Caldwell we p g of MP until the final solution is implemented. recommendations aninterim measures to cantr Deliverables • A cha ter of the Implementation Plan that will contain an analysis of wastewater p characterization data and a summary of the results of the simulations. Assumptions • Ci will Collect sam leS, analyze samples, and provide influent characterization data #a tY p Brown and Caldwell Phase 30O -Develop Options for the Control of MP Three different control options will be developed. ~ . Classi in Selector. A method of decanting surface scum and foam the classifying fY 9 selector will be located within the secondary pump station ASPS}.The overflow will be } um ed to the di esters. Brown and Caldwell will assess the impact this change will have p p g on seconds treatment operations, as well as the +mpact th+s foam has on digester ~ I n showin the operation. Initial equipment and structure sizing will be done, and a site p a g im rovements will be produced. Screening level cost estimates will be produced for p comparison purposes only. 2. Inde endent RAS Return. To prevent the formation of foam in the SPS, return ac#ivated p stud a RAS} will be redirected to the anaerobic zone of the aeration basins. we anticipate 9 ~ .. . . foaming to occur in the aeration basin requiring the use of a classifying selector to remove the foam at the exit of the basin. This foam will then be directly pumped to the digesters. Brown and Caldwell will assess the impact this change will have on secondary treatment o erations, as well as the impact this foam has on digester operation. lnitiaf equipment and p structure sizing will be done, and a site plan showing the improvements will be produced. Screening level cost estimates will be produced for comparison purposes only. 3. Chemical Addition, Addition of polyaluminum chloride and~or sodium hypochlorite will be evaluated for MP control. The City is currently using sodium hypochlorite with limited success. Sites that collect foam in the plant will be inventoried, and chemical feed rates calculated, to deliver chemicals to control 1UIP an a plant-wide basis. Brown and Caldwell will assess the impact this change will have on secondary treatment operations. Initial equi ment and storage structures will be sized, and a site plan showing the improvements p will be produced. Screening level cost estimates will be produced for comparison purposes only. A review meeting will be held to discuss the options. The MP control options will be compared, and one of these options will be recommended based on efficacy and cast. ~,,...,,, deliverables • Options Review chapter of the Implementation Plan • Meeting Minutes documenting selected option Assumptions • Kane 1'~ Phase 400 ~ Implementation Plan for Control of MP are detailed cost estimate will be prepared far budgeting purposes. A schedule will be Am ed shawin the overall schedule for implementing the MP control option and would include prepay g Qesign and Construction tasks. Deliverables • Five copies of the draft Implementation Plan • Five copies of the final Implementation Plan Assumptions • None TIME CAF PERFORMANCE The fallowln table provides a summary of schedule milestones for the plan. g Notice=ta-proceed ~NTPy Completion of wastewater characterization Compete simulation of different operating scenarios Review meeting with. plant. staff Draft Implementation plan for City review Final implementation plan COMPENSATION 104 -Protect Management .. .. .axa.:::::•..xur •x:<:ox<;mxnr:.::.:ar...y;.;;,::.::a:.. , .. 200 -Influent Characterisation and Process Review qiM.•+M:•:~:isi.:iv:.:i•i:9:•iin~i~:•:{•:K•iYiwri:•w4 ' iv1 ~ j•. •. ,...,.~..,....».»...e, 300 - Review Op#ions for the Control of MP 400 -Implementation Plan for Control of MP $6,53 $7,129 $28,949 $$,122 ~~7,~98 --- ' 'Task Order shall be com leted within the Not-To-Exceed The Scope of Services detailed In this p amount of $51,696. Fees will be billed on atime-and-materials basis for actual hours worked per the rate sheet attached to the master agreement dated April 13, 2010, but in no event will fees exceed the Nat-Ta-Exceed amount of $57,696,00 for the services listed herein. Total ASSUMPTIONS The following assumptions. were made in preparation of the. scope of work and fee estimate: • Brown and Caldwell will rely on information provided by the City to prepare the.. technical documents. • Detailed design is not included in this scope and the Preliminary Engineering Report and final design documents are considered follow-on work. CITY OF MERIDIAN By: TAMMY de W D, MAYOR BROWN AND CALDWELL Jeffrey S. Jo , Ph. ., P.G., Vice President Dated : Dated : _ - Z - Z~~C 1~~;1l~;~1R~r~~~ A roved b Cit Council. ~ 5 1 ~ ~~ pp y Y ~ {'"~ ''~~, 0~ v ~~/ ~j \~ ~ •~ / Att t: ~~ '~~ ~ ~ ~~~~ ~ T~ d ~ r i JA CEE . HOLMAN, CITY CLERK w ~~~ .. ~ _ _ .. y o ~ ,~ ,~ ~ •~ C ntent '- 9 ~'sr s~ entA royal Approved as to o ,, ~ ' !~ pp ~~1~ ~o~N~~R~ ,~~~, n KEITH , P ASING AGENT Title: F ~ic.~.N~~ 2~~~- ~ t~-~~.~tc. Dated: 3 1 ~ Dated: 3 ~z 4~~ ~