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Home My WebLink AboutTask Order No. 3 with HDR Engineering, Inc. for Initial Distribution System Evaluation Oversight and Review liR TASK ORDER NO.3 CITY OF MERIDIAN (OWNER) AND HDR ENGINEERING, INC. (CONSULTANT OR ENGINEER) This Task Order is issued by Owner and accepted by the Consultant pursuant to the mutual promises, covenants and conditions contained in the Master Services Agreement between the above named parties, dated January 24, 2007. SCOPE OF SERVICES CITY OF MERIDIAN, IDAHO INITIAL DISTRIBUTION SYSTEM EVALUATION (IDSE) OVERSIGHT AND REVIEW BACKGROUND The US Environmental Protection Agency (EPA) has promulgated the Stage 2 Disinfection Byproduct Rule (DBPR). The objective of the rule is to lower consumer health risks from disinfection byproducts (DBP). The rule affects nearly all community water systems, including the City of Meridian. Initial Distribution System Evaluation To establish permanent DBP monitoring sites, water system operators may be required under the Stage 2 Rule to complete an Initial Distribution System Evaluation (IDSE) unless the water system qualifies for a 40/30 certification (described below). The lOSE is intended to accurately identify monitoring locations within the distribution system that represent high total trihalomethane (TTHM) and haloacetic acid (HAA5) concentrations. Once the IDSE is complete, an IDSE report must be submitted to the primacy agency for review. In order to assist water systems and regulatory agencies through the IDSE process, a draft guidance manual has been provided by the EPA. In accordance with the proposed rule, the 200 page guidance document explains the two options for conducting an IDSE and exemption requirements. Standard Monitoring Program The first option for conducting an IDSE is referred to as the Standard Monitoring Program (SMP). An SMP approach requires one year of distribution system monitoring on a specified schedule throughout the distribution system. The frequency and number of samples required are determined by the system size, the source water type and the number of treatment plants. Under the SMP approach sampling, testing, analysis, site selection and IDSE report completion is estimated to require 15 months of effort. The guidance manual provides sampling site selection advice for meeting IDSE requirements. Site selection is expected to rely on numerous information sources such as water quality data, operating data, tracer studies, hydraulic models, GIS information, maps and others as necessary. The evaluation of selection sites must demonstrate adequate consideration of system information necessary to identify and select appropriate monitoring sites. Page 1 of 7 February 51 2007 M:\Proposals & Quals\Water\City of Meridian\Meridian IDSE\IDSE Task Order3-2007-02-05.doc liR System-Specific Study Another option for conducting an IDSE is to perform a System-Specific Study (SSS) using historical DBP data, water distribution system modeling or a number of other possible approaches. Any results from an SSS must produce equal or superior identification of sites containing high DBP concentrations. Municipalities lacking extensive historical data sufficient to satisfy lOSE requirements may benefit from the development of an lOSE hydraulic model. The cost of SMP sampling and lab analysis can outweigh the investment cost in developing an SSS model. For systems with existing hydraulic models, such as Meridian, the cost benefit can be even greater. The objective of an SSS model is to define water movement patterns and residence time within the distribution system. To satisfy lOSE requirements, models must meet a number of benchmark criteria. Models must be capable of accurately simulating water quality and system operations over extended periods. This requires a detailed model with accurately distributed consumption demands, appropriate diurnal usage patterns and adequate steady-state, extended period and water quality calibration. The model must be detailed enough to represent at least 50 percent of the total system pipe length and 75 percent of the total system pipe volume. Geo-coded water billing records are the recommended method for distributing consumptive demands. Diurnal patterns must vary demands each hour for a week or more during the model simulations. Calibration is expected to address system flows, pressures, tank levels and verify model predicted water age with measured system samples. Meridian's model either fits these critier8 already or could be easily modified to fit these criteria. 40/30 Certification Distribution systems with low historic DBP concentrations, such as Meridian, may be granted 8 certificate in lieu of monitoring under the IDSE requirement. Data must demonstrate that all TTHM results and all HAAS results are less than 40 J.jg/L and 30 J.jg/L, respectively, for at least a two-year period, including all Stage 1 compliance monitoring sites. The required data must be submitted in an lOSE report along with recommendations for where and during which month(s) Stage 2 monitoring should be conducted. Very Small System Waiver A waiver for IDSE monitoring may be issued for small systems if certain criteria are met. This does not apply to Meridian. IDSE Report Except for small systems that have a waiver for IDSE monitoring, all public drinking water systems will be required to submit an IDSE report to the state. The report must include recommendations for Stage 2 monitoring sites and all necessary supporting documentation, such as studies, reports, analytical results, and modeling, the original monitoring plan, a schematic of the distribution system, and a 40/30 certification, if pertinent. PURPOSE The purpose of this task order is to provide oversight and review of a 40/30 Certification Letter and accompanying documentation from Meridian to the EPA, and describe future activities that will be required of Meridian by the EPA or DEQ under the Stage 2 OBP Rule. Page 2 of 7 February 5f 2007 M:\Proposals & Quals\Water\City of Meridian\Meridian IDSE\IDSE Task Order3-2007-02-05.doc liR PROPOSED SCOPE OF SERVICES The proposed scope of consultant services is to conduct the following tasks. ACTIVITY 1. REVIEW 40/30 CERTIFICATION Objective. Provide Meridian with expert review of lOSE materials prior to submittal to EPA. Approach. Consultant will review data, draft letter to EPA, and water system schematic, and Consultant will provide an overall schedule of future IDSE/Stage 2 DBP Rule requirements for the City of Meridian. The following subtasks will be performed: Subtask 1.1. Review Sampling Data. Consultant will review at least 2 consecutive years of DBP monitoring at Stage 1 locations and provide comments regarding the applicability of these data for 40/30 Certification under the Stage 2 OBP Rule. Subtask 1.2. Review 40/30 Certification Letter. Consultant will review draft 40/30 Certification Letter and provide comments to Meridian prior to Meridian's submittal of the letter to the EPA. Subtask 1.3. Review Water System Schematic of Stage 1 DBP Monitoring Locations. Consultant will review the water system schematic which will show the Stage 1 DBP monitoring locations and provide comments to Meridian prior to Meridian's submittal of the 40/30 Certification Letter to the EPA. Subtask 1.4. Develop Multi-Year Schedule of Stage 2 DBP Compliance Activities. Consultant will prepare a schedule of Stage 2 DBP Rule compliance activities that are specific to the City of Meridian. City Responsibilities. City responsibilities are as follows: · Lead communications with EPA and OEQ. · Transmit all three consecutive years of Stage 1 DBP monitoring results to Consultant for review. · Prepare draft 40/30 Certification Letter and accompanying materials from Meridian to EPA for review by Consultant. · Prepare draft Water System Schematic which shows the Stage 1 DBP monitoring locations for review by Consultant. · Prepare final 40/30 Certification Letter and submit to EPA. · Prepare final Water System Schematic which shows the Stage 1 DBP monitoring locations and submit to EPA with 40/30 Certification Letter. . Meet deadlines defined by EPA for Schedule 2 systems. Assumptions. Assumptions are as follows: · This task order does not include preparation of a System Specific Study (SSS) or Standard Monitoring Program (SMP), nor the preparation of a SSS Plan or SMP Plan. Page 3 of 7 February 51 2007 M:\Proposals & Quals\Water\City of Meridian\Meridian IDSE\IDSE Task Order3-2007-02-05.doc liR · City has completed at least 2 years of DBP monitoring and all sampling results are less than half of the Maximum Contaminant Level (MCL) for Total Trihalomethanes (TTHM) and Haloacetic Acids (HAA5). · Deliverables may be provided in electronic form transmitted via email correspondence. Products. Deliverable products are as follows: · Review comments regarding sampling data (if necessary). · Review comments regarding draft 40/30 Certification Letter. · Review comments regarding water system schematic with Stage 1 DBP monitoring locations. · Multi-year schedule of requirements and Stage 2 DBP compliance dates specific to the City of Meridian. Page 4 of 7 M:\Proposals & Quals\Water\City of Meridian\Meridian IDSE\JDSE Task Order3-2007-02-05.doc February 51 2007 liR PROJECT SCHEDULE CITY OF MERIDIAN, IDAHO INITIAL DISTRIBUTION SYSTEM EVALUATION (IDSE) OVERSIGHT AND REVIEW The revised project schedule for performing the review work is as follows: Activity or Milestone Date Notice to Proceed (NTP) Receive Stage 1 DBP Sampling Data from City Provide Comments on Stage 1 Sampling Data to City Receive Draft 40/30 Certification Letter from City Provide Comments on 40/30 Certification Letter to City February 7, 2007 February 9, 2007 February 16, 2007 February 20, 2007 February 26, 2007 March 9, 2007 Provide Schedule of Future Stage 2 DBP Activities Page 5 of 7 February 51 2007 M:\Proposals & Quals\Water\City of Meridian\Meridian IDSE\IDSE Task Order3-2007..02-05.doc liR COMPENSATION CITY OF MERIDIAN, IDAHO INITIAL DISTRIBUTION SYSTEM EVALUATION (InSE) OVERSIGHT AND REVIEW The estimated cost to complete this Scope of Work is presented in the table below. Task Labor Hours Activity 1. Review 40/30 Certification 40 Total 40 HDR will invoice Meridian for professional services described in this Proposal on a time and materials basis. For Activity 1 described in the Scope of Services, HDR estimates a professional services fee of not to exceed $5,000 without written authorization from the City. Page 6 of 7 February 5, 2007 M:\Proposals & Quals\Water\City of Meridian\Meridian IDSE\IDSE Task Order3-2007-02-05.doc liR AUTHORIZATION CITY OF MERIDIAN, IDAHO INITIAL DISTRIBUTION SYSTEM EVALUATION (IDSE) OVERSIGHT AND REVIEW CITY OF MERIDIAN CONSULTANT By: LARRY V. HOFFMAN, VICE PRESIDENT - ~I/.u( j;~ 40 c~@ 2~/J-p1 Attest: ~ S-:1 .... ...-- ( \~~, I~ { j;::' P. " ~L:f~ ,.....~ - - - ~ ~ WILLIAM G. BERG, JR., CITY C~E~ ~&:r 1t~\ . ....1; .f' f --;.. iJ'1 ^ ~ ~ ................. ~y ..... _ ~ '"\~'to: "/., ,~1"1. \", 1"/'1 \'\ !,'tf.~frY.~ ,,\,\,\" Page 7 of 7 February 5, 2007 M:\Proposals & Quals\Water\City of Meridian\Meridian IDSE\IDSE Task Order3-2007-02-05.doc