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R15-149 RESOLUTION NO. R15 -149 N A RESOLUTION OF THE CITY OF BOYNTON BEACH, M FLORIDA, APPROVING TWO TASK ORDERS WITH CH2M FOR A THE PURPOSE OF EVALUATING GROUNDWATER i CONDITIONS, TASK ORDER R13- 063 -08 AND FOR THE DESIGN i AND OVERSIGHT OF LANDFILL COVER REPAIR, TASK 1 ORDER R13- 063 -09, BOTH OF WHICH ARE IN ACCORDANCE • WITH THE CITY'S HYDROGEOLOGICAL CONSULTING 1 . SERVICES AGREEMENT EXTENSION THAT WAS APPROVED 11 BY THE CITY COMMISSION; AUTHORIZING THE CITY 1. MANAGER TO SIGN THE TASK ORDERS ON BEHALF OF THE II 14 CITY; AND PROVIDING AN EFFECTIVE DATE. 11 1; WHEREAS, Task Order R13- 063 -08, in the amount of $166,834.58, contemplates 1 1 continued evaluation of ground water conditions with an emphasis on identification of the 1: source of arsenic; and 1 i WHEREAS, Task Order R13- 063 -09 in the amount of rovides 47 126.26 $ � provides professional design and oversight services for the creation of bid documents to repair the re p � � P 2 landfill cover according to Health Department Standards; and 2P. WHEREAS, the City Commission of the City of Boynton Beach upon 2i recommendation of staff, deems it to be in the best interest of the citizens of the City of 2! Boynton Beach to approve Task Orders R13- 063 -08 in the amount of $166,834.58 and Task 3'n pP 25. Order R13 063 - 09 in the amount of $47,126.26, both with CH2M regarding the landfill. 2 NOW, THEREFORE, BE IT RESOLVED BY THE CITY COMMISSION OF 21 THE CITY OF BOYNTON BEACH, FLORIDA, THAT: 2: Section 1. The foregoing "Whereas" clauses are hereby ratified and confirmed as M n upon adoption 2. being true and correct and are hereby made a specific part o f this Resolutio upo adopt o 3! hereof. 3 Section 2. The City Commission hereby approves Task Order R13- 063 -08 in the S: \CC \WP \Resolutions\2015 \R15 -149 - Task Orders - CH2M - Landfill.doc e amount of $166,834.58 and Task Order R13- 063 -09 in the amount of $47,126.26, both with i ardi the landfill and authorizes the City Manager to sign the Task Orders , g g tY g � I CH2M re copies of which are attached hereto as Exhibits "A." and `B" 3: Section 3. This Resolution shall become effective immediately upon passage. 3 i PASSED AND ADOPTED this 1 day of December, 201 y 2015. 5 31 CITY OF BOYNTON BEACH, FLORIDA 3; 3M YES NO 4 41 Mayor — Jerry Taylor ✓ 4 41 Vice Mayor — Joe Casello 1 4: Commissioner — David T. Merker ✓' 4: 4 1 Commissioner — Mack McCray 4: 4! Commissioner — Michael M. Fitzpatrick 51 5 _ 5• VOTE �— 0 5 5 h ATTEST: 51 5 I. � I a/t .__4 _ 5 J. - t M. Prainito, MMC 5 ` ' I ity Clerk 6 6; ( . r Seal) 6 ' to , S: \CC \WP \Resolutions\2015\R15 -149 - Task Orders - CH2M - Landfill.doc , i , : ,.. 1 ,, ,.. p � y� 4�, --y${ ff ' 4- ' /it ' 4 4•;,, s ; ' 4 . .. i ,.... 4. ...4. tau.. . et • t I ,14 = '4" '; '* .,.. 4, .- . -- 1 .. , ;.% : _-k.. ., ,. f F sd q 1Y. `.. 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Background Since 2010 CH2M HILL Engineers, Inc. (CH2M) has assisted the City of Boynton Beach (City) with the preparation and certification of semi - annual groundwater sampling reports for the City's Class I landfill (Landfill) in accordance with the Palm Beach County Health Department (PBCHD) Permit Number 124522 - 005 -SF for post - closure monitoring. Additionally, CH2M helped the City develop a groundwater investigation program, accepted by the PBCHD, designed to evaluate a decision to cease long -term groundwater monitoring. The hydrogeologic investigation is expected to take place during Fiscal Year 2015/16; this investigation is not considered as part of this scope of work. Concurrently, CH2M's proposed scope of work in this proposal is aligned with the City's goal to meet regulatory guidelines by repairing sections of final cover damaged by erosion during the long -term care period of the City's Landfill. The professional services consist of the following activities, which are detailed in the Scope of Work: • CH2M will conduct a brief site visit to review the findings of the September 3, 2015 Florida Department of Environmental Protection Inspection Checklist. • CH2M will convene a teleconference with Florida Department of Environmental Protection (FDEP) officials to confirm the process and requirements to obtain regulatory approval for required remedial actions prior to the City procuring a qualified contractor and commencing repairs to the final cover system;CH2M will facilitate a teleconference with the City and the Lake Worth Drainage District (LWDD) to discuss procurement of access approval and to memorialize any LWDD permit or restoration requirements in the procurement package prepared by the City; • CH21VI will prepare a written corrective action plan (CAP) as required by Question 3.4 in the September 3, 2015 Florida Department of Environmental Protection Inspection Checklist. It is assumed that the design criteria package including a grading plan will serve as the basis for the CAP, which will be submitted to FDEP by the City. • CH21VI will prepare a design criteria package, which will be included in the procurement package prepared by the City; • CH21VI will prepare an opinion of probable construction cost based upon estimated quantities. The estimate will include mobilization / demobilization, granular fill, topsoil, and sod or seed covering; • CH21VI will serve as a technical resource during the bid review process; and • CH21VI will provide limited services during construction including submittal reviews and field observation necessary to prepare the certification of construction completion documentation at the conclusion of the project for submission to FDEP.. PAGE 1 OF 7 B. Scope of Services The scope of services included in this authorization are as follows: Task 1 —Site Visit and Teleconference with FDEP CH2M will conduct a brief site visit with City staff to review the findings of the September 3, 2015 Florida Department of Environmental Protection Inspection Checklist. CH2M will then facilitate a teleconference with the City and FDEP to confirm the requirements to obtain regulatory approval for required remedial actions prior to commencing repairs to the final cover system. CH2M will prepare a meeting agenda for distribution and discussion with attendees. The teleconference is expected to last up to two (2) hours. Following the meeting, CH2M will prepare a draft meeting summary, identifying critical discussion points for review and comment by all participants. For budgetary purposes, it is assumed the Principal, Senior Project Manager and Project Manager will participate in the teleconference on behalf of CH2M. Deliverables w Agenda, electronic - Draft and Final Meeting Summary (draft for review by all) Task 2 — Teleconference with LWDD CH2M will facilitate and participate in a teleconference with the City and LWDD representatives to negotiate access approval to the site and address any LWDD requirements in the procurement package prepared by the City. For budgetary purposes, it is assumed the Principal and Senior Project Manager will participate on behalf of CH2M. Deliverables - Agenda, electronic - Draft and Final Meeting Summary (draft for review by all) Task 3 — Produce Bid Package and Bid Form CH2M will prepare a written corrective action plan that will serve as the basis for the bid package that includes construction drawings, technical construction specifications, a site plan that delineates the work limits and a grading plan. The bid package will be incorporated into the procurement package prepared by the City. It should be noted that CH2M will need to obtain current topographic information from the City to prepare preliminary design drawings. It is assumed that the City will engage a qualified surveying firm to perform a pre- construction survey. CH2M will provide technical assistance to the City to develop the scope of work for the selected surveying firm. Using the pre- construction survey, CH2M will develop plans for construction of the final cover of portions where erosion damage has occurred and will include standard erosion control drawings or FDOT call outs (e.g., silt fence, hay bales) where needed. PAGE 2OF7 CH2M will prepare and submit a draft bid package for the City's review and comment. For budgetary purposes, it is assumed that the Senior Project Manager and Project Manager will participate in a teleconference with the City following the draft submittal to discuss written comments received from the City and respond to questions. The City is requested to provide one set of consolidated written comments prior to the teleconference. CH2M will respond to the City's comments to finalize the bid package that will be incorporated into the procurement package prepared by the City. Once the bid package has been approved by the City, CH2M will provide electronic files. CH2M will prepare a bid form in MS -Word format for inclusion in the City's front -end documents. Deliverables — Draft and final corrective action plan. — Draft and final bid package. — Bid Form. Task 4 — Prepare an Opinion of Probable Construction Cost CH2M will prepare an opinion of probable construction cost based upon estimated quantities. The estimate will include mobilization /demobilization, granular fill, topsoil, and sod or seed covering. Bid quantities will be based upon either LS, CY or SY as appropriate. CH2M will perform a quantity take -off based on the best available information, including the most recent FDEP Inspection Report. Deliverable - Opinion of Probable Construction Cost based upon estimated quantities. Task 5 — Contractor Selection Assistance CH2M will assist the City as a technical resource during the bid evaluation phase. Activities include attending the pre -bid meeting and providing technical input during the evaluation including responding to bidder questions and preparing addenda. Once bids are received, CH2M will review the bids submitted and provide a summary for City consideration prior to contractor selection. CH2M will conduct a teleconference with the City to discuss pro and cons, as well as any outstanding issues related to CH2M's technical review. Deliverables - Attend pre -bid meeting. Respond to bidder questions and provide technical input to addenda. - Prepare draft and final bid evaluation summary memorandum. PAGE 3 OF 7 Task 6 — Services During Construction CH2M will provide services during construction including reviewing and responding to up to fifteen (15) contractor submittals including the location of the borrow pit(s) where granular material and topsoil will be obtained. CH2M's field support includes daily observation by one CH2M staff member (4 hours) for 10 days. Following project completion, CH2M will draft, finalize and submit to FDEP an application for certification of construction completion, signed and sealed by a professional engineer, at the completion of this project. A draft of the application for certification of construction completion will be submitted for review and comment by the City. CH2M will adjudicate City comments and finalize the application prior to submission to FDEP. Following submittal to FDEP, CH2M will respond to up to 2 (two) Requests for Additional information within this task order. Upon acceptance by FDEP, the Certification of Construction Completion should be placed in the operating record. Deliverables - Submittal Review Forms Submittal Tracking Log - Construction Logbook - Draft and final certification of construction completion for submission to FDEP - Response to up to 2 (two) Requests for Additional information C. Assumptions This estimated cost is based on the following assumptions: • Additional meetings with the City, FDEP, PBCHD or the contractor are not included in this scope of services. • The City will be responsible for satisfying any site access requirements negotiated under Task 2. • The City will complete the site survey by December 4, 2015. • The City will be responsible for managing the procurement process and meeting the timelines presented in the Consent Order. • The City will review and provide comments on the draft Bid Package and draft Bid Form within one (1) week of submittal by CH2M. • The City will be responsible for submitting all required documents to the PBCHD as specified in the Consent Order. • CH2M is not responsible for City nor contractor delays that result in penalties specified in the Consent Order. • No subcontractors will be utilized by CH2M during the delivery of the scope included herein. • The City is responsible for continuing the yearly maintenance program implemented for the post closure monitoring period as specified in the Consent Order. • If the duration of the selected Contractor's work is greater than the time assumed in this Task Order or if the City self - performs some of the inspections during construction, the level of effort for the services during construction may be amended. PAGE 4 OF 7 D. Contract Reference This Task Order shall be performed under the terms and conditions described within the Agreement titled Hydrogeological Consulting Services, dated August 19, 2013, between the City of Boynton Beach and CH2M Hill Engineers, Inc., as amended. E. Compensation Compensation by the City to CH2M will be on a time and materials basis in accordance with the above - mentioned Agreement. The estimated compensation for the services described in this Task Order is $47,126.26 as presented in Table 1. TABLE 1. TASK HOURS RATE TOTAL 1. Site Visit and Teleconference with FDEP Engineer 12 $120.00 $1,440.00 Senior Engineer 2 $155.00 $310.00 Senior Project Manager 4 $208.14 $832.56 Expenses $150.00 SUBTOTAL $2,732.56 2. Teleconference with LWDD Engineer 4 $120.00 $480.00 Senior Engineer 2 $155.00 $310.00 Senior Project Manager 4 $208.14 $832.56 Expenses $0.00 SUBTOTAL $1,622.56 3. Produce Design Criteria Package and Bid Tab Office 6 $86.22 $517.32 Engineer 60 $120.00 $7,200.00 Senior Engineer 10 $155.00 $1,550.00 Senior Project Manager 17 $208.14 $3,538.38 Expenses $0.00 SUBTOTAL $12,805.70 4. Prepare an Opinion of Probable Construction Cost Engineer 14 $120.00 $1,680.00 Senior Engineer 2 $155.00 $310.00 Senior Project Manager 4 $208.14 $832.56 Expenses $0.00 SUBTOTAL $2,822.56 S. Contractor Selection Assistance PAGE 5OF7 Office 6 $86.22 $517.32 Engineer 16 $120.00 $1,920.00 Senior Engineer 12 $155.00 $1,860.00 Senior Project Manager 16 $208.14 $3,330.24 Expenses SUBTOTAL 6. Services During Construction $100.00 $7,727.56 Office 40 $86.22 $3,448.80 Engineer 80 $120.00 $9,600.00 Senior Engineer 4 $155.00 $620.00 Senior Project Manager 18 $208.14 $3,746.52 Expenses SUBTOTAL TOTAL $2,000.00 $19,415.32 $47,126.26 F. Schedule CH2M estimates that its scope of work will be completed as presented below in Table 1. Every effort will be made to expedite the completion of the tasks. Table 1 Prniert Schedule Activity Target Completion Date Notice to Proceed issued to CH2M December 2, 2015 Site Visit and Teleconference with FDEP December 31, 2015 Teleconference with LWDD January 8, 2016 Draft Bid Package and Bid Form January 29, 2016 Final Bid Package and Bid Form February 12, 2016 Submit an Opinion of Probable Construction Cost February 12, 2016 City Advertises Bid Pursuant to the Consent Order March 4, 2016 Contractor Selection Assistance April 22, 2016 Services During Construction June 24, 2016 PAGE 6 OF 7 G. Authorization APPROVED BY: CITY OF BOYNTON BEACH, FLORIDA By: m. . Q�. �.. V3 " Dated this S day of NovL- rbtT - 2015. SUBMITTED BY: CH2M By. Matthew B. Alvarez, PE Vice President and Area Manager Dated this 6 day of November, 2015 APPROVED AS TO FORM: .N .�. CITY PAGE 7 OF 7 F -kqg Task Order No. R13- 063 -08 Professional Hydrogeologic Services for Investigating the Origin of Arsenic in Groundwater at the City of Boynton Beach Landfill, Palm Beach County Health Department Permit 124522 - 005-SF A. Background Since 2006 groundwater sampled semiannually at monitoring wells surrounding the City of Boynton Beach (City) Municipal Landfill (BBLF) has displayed concentrations of arsenic exceeding the Florida Department of Environmental Protection's (FDEP) Groundwater Cleanup Target Level (GCTLs) of 10 micrograms per liter (µg /L). Over the monitoring period, the highest concentrations were observed in MW -12, reaching a maxima of 311 pg /L in October 2007. Under FDEP Solid Waste Permit No. 124522 - 005 -SF, BBLF completed a 20 -year period of post closure monitoring in February 2012, followed by multiple extensions, which include ongoing semiannual sampling events. As specified under Florida Administrative Code (FAC) Chapters 62 -701 and 403, following post - closure monitoring, if concentrations of water quality constituents remain above the GCTL's, FDEP may require the facility to undergo compliance evaluation and corrective action measures. These measures can involve expensive, long term actions including the remediation of groundwater, until constituent concentrations meet GCTL's. However, a groundwater study funded by the City at the adjacent (west) Links at Boynton Beach golf course in 2012 revealed similar results to BBLF, with concentrations of arsenic in groundwater exceeding GCTL's at six of 12 monitoring wells involved in the study. Moreover, concentrations in monitoring wells from the golf course exceeded the historic maxima at the BBLF by over one order of magnitude. Similarly, an investigation of arsenic in groundwater samples from local (supply and monitoring) wells contained in the National Water Institute System (NWIS) and DBHYDRO databases maintained by the United States Geological Survey (USGS) and South Florida Water Management District, respectively, revealed multiple wells exhibiting arsenic concentrations exceeding the GCTL. Maximum concentrations obtained from the databases reached 207 ug /L, at a well less than five miles east of BBLF. Constituents analyzed in characterizing the geochemistry of the shallow groundwater at the golf course, and the NWIS and DBHYDRO databases suggests conditions are favorable to the reductive dissolution of iron, a major contributor to elevated arsenic concentrations in groundwater worldwide. Arsenic occurs naturally in groundwater from shallow aquifers, comprised of recent sediments, in large regions of Bangladesh, West Bengal, Taiwan, and Cambodia, along with areas of the United States (northern New York, New Hampshire, Wisconsin, Minnesota, and California). A natural origin for arsenic in groundwater holds important implications for post - closure activities at BBLF, particularly regarding potential future remedial measures required of the City. The appearance of elevated concentrations at BBLF, the gold course, and the surrounding area (NWIS and DBHYDRO databases) implies a more wide - ranging natural cause for arsenic in groundwater than potential anthropogenic causes at BBLF. To test this hypothesis, in late 2013 the City funded development of a sampling plan designed to characterize geochemical conditions in groundwater at BBLF and their contribution to the natural occurrence of arsenic. The Palm Beach County Board of Health ( PBCBH) and Florida Department of Environmental Protection (FDEP) reviewed and endorsed the sampling plan with minimal comment. This proposal describes the scope of work, costs, and schedule for CH2M to execute the field investigation outlined in the sampling plan. Comprising four quarters of groundwater sampling, the investigation will follow the FDEP's Guidance for Comparing Background and Site Chemical Concentrations in Groundwater (Guidance), in demonstrating that elevated arsenic in groundwater represents an ambient condition in the Surficial Aquifer. The investigation will also focus on the geochemical origins of arsenic in groundwater. The original sampling plan submitted to PBCHD in September 2013 described 12 monitoring wells including the eight monitoring wells from BBLF, and four (MW -2 through 4, and MW -8) from the golf course. As part of the BBLF study, the four monitoring wells from the golf course complied with FDEP's Guidance for Comparing Background and Site Chemical Concentrations in Groundwater, which requires three monitoring wells located hydraulically up or side gradient from the subject facility and intended to monitor ambient water quality in the subject aquifer. Water quality from the ambient wells are combined in statistical analyses with analytical data from wells at the facility. The fourth well provides an additional point for characterizing ambient water quality, or an alternative to one of the other three wells for applying the analyses. The golf course monitoring wells involved in the 2012 study were abandoned, including the wells selected for BBLF's arsenic study, during summer 2014. Although conducting the study without the wells from the golf course can still reliably determine the geochemical origin of arsenic, the study will not fit into a regulatory framework that supports proclaiming a natural origin for arsenic, and reducing the City's future obligations. Accordingly, to meet the requirements of FDEP's guidance, CH2M will install four replacement monitoring wells at the golf course within 5 to 10 feet of the former locations of MW -2 through 4, and MW -8. B. Scope of Services CH2M's scope of work will consist of the following five tasks: Task 1- Prepare for Drilling and Sampling Events Task 2- Install Monitoring Wells at the golf course Task 3- Conduct Quarterly Sampling Events Task 4 -Data Reduction and Analysis Task 5- Prepare Investigation Report Task 6- Regulatory Support Task 1 Prepare for Drilling and Sampling Events Task 1 will entail preparing personnel and equipment for the four quarters of sampling at BBLF. This effort will involve the following activities: • Conducting a site visit to BBLF and the golf course • Locating monitoring wells at the golf course • Obtaining pricing and subcontracting a laboratory licensed in Florida • Obtaining pricing and subcontracting a drilling contractor licensed in Florida • Procuring sampling equipment • Obtaining instrumentation to measure important field chemistry parameters • Obtaining access to locations on the golf course Properly preparing for installing four monitoring wells and the quarterly sampling investigation will ensure that field efforts will proceed with minimal concerns, or problems. Conducting a site visit will prove important in siting the replacement monitoring wells, identifying methods to measure synoptic water levels, efficiently sampling monitoring wells at both sites, and disposing of purge water. Task 2 Install Monitoring Wells at the Links at Boynton Beach Golf Course After subcontracting a qualified drilling firm, CH2M personnel will supervise the installation of the four new monitoring wells adjacent to the former locations of MW -2, MW -3, MW -4, and MW -8 at the golf course, re- designating the well numbering as MW -213, MW -3R, MW -4R, and MW -8R. Well depths and screen lengths will reproduce the elevations and dimensions of the original wells, respectively. Qualified CH2M staff will describe the lithology of samples recovered during drilling, and supervise construction of the monitoring wells. A critical element of a groundwater monitoring program will entail collecting samples free of sediment and turbidity. Accordingly, the driller contractor will execute an aggressive mechanical development effort involving both swabbing and pumping techniques. CH2M personnel will oversee development of each monitoring well. Obtaining the most representative samples may require developing a single monitoring well for one to two days. CH2M will prepare a memorandum describing the drilling, monitoring well installation and development activities. The memorandum will contain boring logs with lithological descriptions, monitoring Well construction diagrams, and development forms. Task 3 Conduct Quarterly Sampling Events Under Task 2, CH2M will conduct four quarters of groundwater sampling over a 12 -month period. CH2M will collect samples from the eight remaining monitoring wells at BBLF, and MW -2, MW -3, MW -4, and MW -8 at the golf course (Table 1). These quarterly sampling events will supplant the post - closure monitoring sampling over the 12- months of this study. In addition to the 12 groundwater samples, CH2M personnel will collect one field duplicate, a matrix spike /matrix spike duplicate (MS /MSD) and one equipment blank during each of the four quarterly events. The MS /MSD will get collected at the same monitoring well as the field duplicate. Prior to each sampling event, personnel will collect one equipment blank by passing distilled water through the tubing used with the peristaltic pump to purge the monitoring wells. In following FDEP's Guidance for Comparing Background and Site Chemical Concentrations in Groundwater, the field investigation will incorporate a minimum of three background monitoring wells set in the Surficial Aquifer located side or up- gradient from BBLF, quarterly samples collected over one year, along with simple and statistical evaluation of site and background data. A Florida - certified laboratory will analyze all samples for total arsenic and dissolved arsenic over each of the four quarters. Samples collected during the first and fourth quarters, will get analyzed for a comprehensive list of water quality parameters, with a smaller list of analytes for the second and third quarters (Tables 2 and 3). CH2M will purge the wells according to most recent version of the FDEP Standard Operating Procedure (DEP -SOP 001/01), dated March 2008. The crews will discharge purge water onto the ground surface topographically downgradient of each monitoring well. Sampling crews will measure and record important water quality parameters on the field parameter data sheets. These parameters will include temperature, pH, conductivity, DO, oxidation - reduction potential (ORP), sulfate, sulfide, total iron, ferrous iron, manganese, alkalinity, and turbidity. Moreover, the sample crews will measure the depth -to- waterto water at each well overthe four quarterly sampling events. The surface water stations at SW -E -3 and SW -L -20 will remain in service for obtaining surface water elevations. TABLE 1 Summary of Monitoring Wells Used for the Study BBLF Links at Boynton Beach Golf Course MW -12 MW -2 R MW -15 MW -3 R MW -18 MW-4 R MW -19 MW -8 R MW -A -3 Turbidity MW -B -3 MW -C -3 mg /L. MW -D -3 Field Iron (ferrous) TABLE 2 Summary of Field and Laboratory Water Quallty Test Res — Quarters 1 and 4 Sample ID Constituent Units Federal Drinking Water Standards pH standard units 6.5-8.5 Eh (corrected) my Specific Conductivity emhos Dissolved Oxygen mg /L Temperature °C Turbidity NTU Field Sulfate mg /L. 250 Field Iron (ferrous) mg /L 0,3 Field Iron (total) mg/L. 0.3 Field Manganese mg/L. 0.05 Field Alkalinity mg /L Field Sulfide mg/L. Aluminum dissolved mg/L. 0.2 Aluminum total mg/L. 0.2 Arsenic dissolved mg/L. 0.005 Arsenic total mg/L. 0.005 Iron (dissolved) mg/L. 0.3 Iron (total) mg/L. 0.3 Manganese dissolved mg /L 0.05 Manganese total mg/L. 0.05 Magnesium total mg/L. 5 TABLE 2 Summary of Field and Laboratory Water Quality Test Results — Quarters 1 and 4 Sample ID Constituent Units Federal Drinking Water Standards Potassium total mg /L Sodium total mg /L 50 Calcium total mg/L. Sulfate mg /L 250 Chloride mg/L. 250 Alkalinity rng /L 250 Ortho- Phosphate mg /L 0.3 Totai Phosphorous mg /L 0.3 Nitrate as N mg/L. 10 Total Kjeldahl Nitrogen mg /L Ammonia mg /L Fluoride mg/L. 2 . 0 Silica mg/L. Totai organic carbon mg /L Total dissolved solids mg /L 500 Total suspended solids mg/L. Hardness mg/L. TABLE 3 _Summary of Field and Laboratory Water Quality Test Results — Quarters 2 and 3 Sample ID Constituent Units Federal Drinking Water Standards pH standard units 6.5-8.5 Eh (corrected) my Specific Conductivity emhos Dissolved Oxygen mg /L Temperature °C Turbidity NTU Field Sulfate mg/L. 250 Field Iron (ferrous) mg /L 0.3 Field Iron (total) mg /L 0.3 Field Mangarese mg/L. 0.05 Field Alkalinity mg /L Field Sulfide mg /L 6 TABLE 3 Summary of Field and laboratory Water Quality Test Results — Quarters 2 and 3 Sample ID Constituent Units Federal Drinking Water Standards Arsenic disso!ved mg /L 0.005 Arsenic total mg /L 0.005 Task 4 Data Reduction and Analysis Characterizing the results of the field investigation data from Task 2 represents an important step in determining the origin of arsenic in groundwater at BBLF. Accordingly, Task 3 will entail evaluating hydrologic results, statistical analyses following FDEP's guidance, geochemical evaluations of redox conditions, potential arsenic bearing minerals, and mechanisms for arsenic release. Analysis of hydrologic results will comprise characterizing groundwater flow directions, and hydraulic gradients for individual sampling events, along with the changing potentiometric surfaces over the four events. Most importantly, CH2M will describe the hydrologic relationship between the BBLF and the golf course to document that the upgradient monitoring wells remain the same for each event, Upon receipt of sample results from the laboratory, CH2M's project chemist will validate the data to verify that proper field, sample management, and laboratory protocols were followed. After validation, evaluation of the water quality data will involve applying deterministic statistics (mean, mode, median, standard deviation, etc.), and other tests to better understand temporal trends in selected parameters. In following FDEP's Guidance, project personnel will review laboratory data for arsenic using the "Simple Approach for Comparing Site and Background Data" along with a statistical approach like the student — t test, or the Mann - Whitney Test. Both techniques can test the null hypothesis when comparing two populations. As data from the golf course, NWIS, and DBHYDRO suggests elevated arsenic is related to the reductive dissolution of iron, CH2M will apply several analytical techniques to evaluate redox conditions at BBLF. In addition to field measurements of the oxidation - reduction potential (ORP), CH2M will employ a method developed by Stuyfzand (1993) and the Redox- Assignment program (McMahon et Al, 2009) in identifying the prevalent redox processes. CH2M may evaluate release mechanisms for arsenic (ex: sulfide oxidation, reductive dissolution of iron, competitive adsorption, desorption with elevating pH, etc.) using thermodynamic equilibrium models like PHREEQC (Parkhurst, 1994), or MINTEQA2 (Allison, 1991). By calibrating the models to conditions at BBLF, CH2M can run simulations that predict how arsenic concentrations respond to varying geochemical conditions. As an example, the redox chemistry of groundwater can vary with seasonal changes in recharge and water table elevations, causing arsenic concentrations to fluctuate. Calibrating a model like PHREEQCto site conditions allows predicting a range of arsenic concentrations with time. CH2M will test the sensitivity of the modeled solution to changes in critical input parameters. Using this approach, sensitivity testing will quantitatively assess the uncertainty of the modeled solution. Task 5 Prepare Investigation Report CH2M will prepare a draft groundwater investigation report following collection of the fourth quarterly round of sampling. The report will contain the results of synoptic surveys, water quality sampling, a geochemical evaluation, modeling, and recommendations for future activities. CH2M will submit one electronic and five hard copies of the report to the City for review by the staff of the engineering department, Palm Beach County Health Department (PBCHD) and FDEP. We will incorporate comments into a final version of the report, and submit one electronic, and five hard copies to the City. Task 6 Regulatory Support Under Task 5, CH2M will provide the City with regulatory support as required during this project. For costing purposes, we assume CH2M will perform the following activities during Task 5: • One telephone conference (2 hours) with regulators from PBCHD and /or FDEP prior to initiating field work. • Preparing a memorandum following each sampling event (4 memoranda), containing tabulated field and laboratory chemistry data. • Responding to requests for information (5), or questions from PBCHD and FDEP during the 12 -month sampling interval. • Conducting a meeting (1) with the City, PBCHD, and FDEP following the field investigation to report tentative sampling results. • Responding to comments on the Draft Investigation Report from Palm Beach County and FDEP. • Negotiating with regulators from PBCHD and FDEP on final closure activities at BBLF Should sampling turn out as expected, the crucial important element of Task 5 will involve convincing PBCHD and FDEP that arsenic in groundwater at BBLF originates from naturally- occurring causes, and accordingly, no active remedial measures are required, C. Assumptions This estimated cost is based on the following assumptions: • The CITY will assist CH2M personnel in gaining access to drilling locations for MW -2R, MW- 3R, MW -4R and MW -8R and then the completed monitoring wells for sampling. • CH2M personnel will conduct all field sampling activities. • CH2M will subcontract a drilling contractor licensed in the state of Florida to drill and install the monitoring wells. • CH2M will subcontract a laboratory certified in the state of Florida to analyze four quarters of sampling. ® CH2M will manage and verify validity of analytical data. • CH2M will prepare a brief memorandum after installing the monitoring wells describing drilling, installation, and development activities. The memorandum will include boring logs, monitoring well construction diagrams, and development forms. • CH2M will prepare a brief memorandum following each quarterly sampling event including a summary table of water quality, Florida Drinking Water Standards and exceedances; CH2M will supply an electronic copy, along with five hard copies of the draft and final to the CITY for delivery to PBCHD; D. Contract Reference This Task Order shall be performed under the terms and conditions described within the Agreement titled Hydrogeological Consulting Services, dated August 19, 2013, between the CITY of Boynton Beach and CH2M HILL Engineers, Inc. E. Compensation Compensation by the CITY to the CONSULTANT will be on a time and materials basis in accordance with the above - mentioned Agreement. The estimated compensation for the services described in this Task Order is $ 166,834.58 as shown in Table 1. This fee includes a contingency allowance which may be used with the approval of the CITY Public Works Director for additional costs associated with this Task Order. Table 4 Task Personnel Rate Hours Total Prepare for Drilling and Sampling Monitoring Well Installation Quarterly Sampling Data Reduction Report Preparation Office 86 6 $516.00 Junior Engineer 90 28 $ 2,520.00 Engineer 120 40 $ 4,800.00 Project Manager 138 12 $ 1,656.00 Senior Technologist 192 10 $ 1,920.00 Expenses $ 709.20 Office 86 4 $ 344.00 Junior Engineer 90 $ - Engineer 120 120 $ 14,400.00 Project Manager 138 16 $ 2,208.00 Senior Technologist 192 24 $ 4,608.00 Expenses $ 16,527.60 Office 86 8 $ 688.00 Junior Engineer 90 120 $ 10,800.00 Engineer 120 120 $ 14,400.00 Project Manager 138 24 $ 3,312.00 Senior Technologist 192 12 $ 2,304.00 Expenses $ 32,013.80 Office 86 0 $ - Junior Engineer 90 48 $ 4,320.00 Engineer 120 8 $ 960.00 Project Manager 138 16 $ 2,208.00 Senior Technologist 192 32 $ 6,144.00 Expenses $ 236.80 Office 86 8 $ 688.00 Junior Engineer 90 0 $ - Engineer 120 16 $ 1,920.00 Project Manager 138 16 $ 2,208.00 Senior Technologist 192 40 $ 7,680.00 Expenses $ 346.00 10 Regulatory Support Office 86 8 $ 688.00 Junior Engineer 90 0 $ - Engineer 120 32 $ 4,840.00 Project Manager 138 24 $ 3,312.00 Senior Technologist 192 16 $ 3,072.00 Expenses $ 318.40 Subtotal 840 $ 151,667.80 Contingency 10% of Subtotal $ 15,166.78 Total $ 166,834.58 F. Schedule CH2M will initiate the drilling and well installation activities within six weeks of receiving a Notice to Proceed from the City. CH2M will conduct the first quarterly sampling event two weeks after developing the monitoring wells. We will submit a memorandum to the City containing field and laboratory chemistry results six weeks after each quarterly sampling event. CH2M will submit a draft report to the City eight weeks following the fourth quarterly sampling event, and the final report two weeks after receiving comments from PBCHD, FDEP, and the City. �� Authorization ��' G. �nunu�n�����=^�on APPROVED BY: CITY OF BOYNTON BEACH, FLORIDA 8y APPROV AS TO FOR M; NEY Dated this , day of 2015. SUBMITTED BY: CH2K8 HILL Engineers, Inc. By: Kotus Watson, PE Vice President, Florida Geographic K8ana8er Dated this day of 2015. 12