HomeMy WebLinkAboutTask Order 10284 with CH2M Hill, Inc. for Iron and Manganese Pilot TestingTASK ORDER NO. 10284
Under the
MASTER AGREEMENT FOR PROFESSIONAL SERVICES
BETWEEN
CITY OF MERIDIAN (OWNER) AND CH2M HILL, INC (ENGINEER)
This Task Order is made this _19th day of September, 2011 and entered into by
and between the City of Meridian, a municipal corporation organized under the laws of
the State of Idaho, hereinafter referred to as "City", and accepted by CH2M HILL INC,
hereinafter referred to as "Engineer" pursuant to the mutual promises, covenant and
conditions contained in the Master Agreement between the above mentioned parties
dated January 1, 2007. The Project Name for this Task Order 10284 is as follows:
City of Meridian
Iron and Manganese Pilot Testing
Project Understanding
The City has historically been monitoring water quality at the source and throughout the
distribution system. From time to time under certain conditions the City has experienced
water quality customer complaints associated with odor and visual clarity. Although these
conditions are viewed as secondary contaminants they are none the less still concerning
to the customer, and overall to the distribution system condition and degradation.
Complaints and concerns from both residential and commercial customers has caused
the City to take a closer look at what is occurring and how these conditions and the
resultant events can be mitigated or eliminated. As a first step in this process the City has
elected to conduct pilot testing of potential treatment or conditioning systems with the
goal of identifying potential solutions to eliminate these conditions and the resultant
customer complaints/concerns.
SCOPE OF SERVICES
CH2M HILL will perform the following activities and tasks for the pilot testing as outlined
below.
Project Management
Project management will consist of supervision and coordination of CH2'sproject staff;
documenting meeting decisions and action items; monitoring project progress; monitoring
project activities for potential changes; anticipating changes when possible; and with City
approval, modifying project tasks, budgets, and approach; preparation and submission of
invoices for services performed; and coordination and facilitation of project quality control
reviews of all deliverables on this project.
Engineer Provided Equipment
CH2M HILL will provide pilot testing equipment, chemical feed equipment and field
analytical equipment for the pilot test period. The equipment will include:
Task Order 10284 Page i of 5
Iron and Manganese Pilot Testing
• Four 4" by 60" columns filled with media
• All piping necessary to provide 10-15 gpm of flow for the pilot test
• Chlorine, and permanganate solution tanks
• Chemical feed pumps for chlorine, and permanganate injection
• Flow meters to measure instantaneous and totalized flow
• Field analytical equipment to measure pH, alkalinity, iron, manganese, free and total
chlorine and ammonia
Physical Characteristics of Pilot Filter Set and Media
Pilot Filters
Sidewall Height (inches)
Overall Height (inches)
Diameter (inches)
Filter Surface Area (each) (ft.2)
Total Filter Surface Area (ft2)
Underdrain
Media Support
Source Water Connections
Recommended Maximum Working Pressure
Filter Med
Depth in Filters (inches)
Volume in Filters (ft3)
Approximate Weight in Filters (lbs.)
Weight (lbs./ft3)
Physical Size (US Mesh)
Maximum Removal Capacity
Iron Removal (mg/L)
Manganese Removal (mg/L)
Hydrogen Sulfide Removal (mg/L)
Nan Adsorptive Removal (microns)
Chemical Dosing Equipment
Various Solution Metering Pumps (capacities vary)
60
72
4
0.0872
0.3488
Stainless Steel Wedgewire, 0.01" slots
minus crushed granite, 4"
Standard Hose
50 psi
36 to 42"
0.261 to 0.3052
39
125
20-40 US Mesh (pyrolusite), 0.45-0.5 mm
(sand), 0.9 to 1.1 mm anthracite, 20-60 US
Mesh (greensand)
10
10
5
>20
1. The pilot filters consist of four, 4" filter columns connected by separate 1/2" lines for influent, effluent and backwash
water. Each filter is controlled by ball valves. Source water is metered using a totalizing flow meter. Pressure is
measured on the influent and effluent manifold to determine headloss. Chemical injection points are located as
close to the lifter as possible to simulate actual operation. In cases where extended contact time is desired before
the source water enters the filters, a pipe section of pre -determined volume is placed between the chemical
injection points and the filters to provide accurate contact time measurement. The filters are disassembled and
cleaned between each pilot test location to prevent cross -contamination.
2. The manganese dioxide granules (pyrolusite) used as filter media is at least 85 percent Mn02. All media will be
NSF certified.
3. Solution metering pumps are available for the injection of up to three chemicals, if needed.
City Provided Assistance, Equipment, and Information
The City will assist in providing access to the pilot sites including connections and taps to
the water supply and power required by the pilot system and water quality data as
follows:
Task Order 10284 Page 2 of 5
Iron and Manganese Pilot Testing
Site Requirements for Testing
• Power, 110 VAC (15 — 20 amp circuits) for injection equipment and lighting
• Source water, minimum 10 gpm, minimum 30 psi
• Access to site
• Disposal of treated water (10 —15 gpm) and backwash effluent (10 gpm for 4 to.5
minutes)
Data Needed from Utility
• Inorganic test results (most recent)
• Well log
• Pump curve
• Drawing of well building and site
• Standard building layout or specification
• Water rights permit, or permitted quantity of flow
• Existing electrical capacity at site
Conduct Bench Study
CH21V! HILL will conduct a bench top test of three different sequestering agents:
calciquest, sodium silicate and Aqua -Mag. The test will include collection of water
samples, and daily filtration with a 0.45 micron filter and testing for iron and manganese
concentrations to determine the effectiveness of the sequestering agents. Samples will
be dosed with 4 to 8 mg/L of sequesterant depending on the manufacturer's
recommendations, and held in simulated distribution system conditions (55 degrees, no
sunlight).
Conduct Pilot Study
Pilot tests will be conducted for one week to determine the recommended conditions at
the well sites for optimized iron and manganese removal. CH2M HILL will pilot test Well
No. 22 for up to 3 days followed by brief % day tests at three other wells selected by the
City.
Processes tested will include:
• Adsorptive iron and manganese removal with manganese dioxide media.
Samples are collected at 30 to 60 minute intervals throughout the pilot test. The following
field tests are normally taken.
Field Testing Parameter Frequency
pH 30 minutes or continuous
Free Chlorine Residual 30 minutes or continuous
Iron, Total 30 to 60 minutes
Manganese 30 to 60 minutes
Alkalinity Daily
Ammonia Twice Daily
Chlorine Solution Strength Daily or more frequently, if concentration is changed.
Hydrogen Sulfide 60 minutes to daily, depending on variability.
Backwash effluent samples will also be collected and analyzed to help in the preparation
of any backwash water treatment, disposal or recycling recommendations.
Task Order 10284 Page 3 of 5
Iron and Manganese Pilot Testing
Analysis of Results
Results of the bench and pilot testing will be analyzed to determine the efficiency of the
filters at sequestering and removing iron and manganese from the source water. The data
will be presented in tabular and graphical form showing operating conditions, removal
efficiencies and chlorine dose and residual levels.
Preparation of Pilot Study Report
A draft and final Pilot Study Report will be prepared detailing the results of the pilot testing
and an analysis of the variables used in the pilot test. The report will include an evaluation
of the technical feasibility of using the treatment process on the source water,
development of a basis of design and planning level cost estimates for a full-scale facility.
The Pilot Study Report will be in a format suitable for review by City staff and
management, for presentation to the City management and/or City Council and for
submission to the Idaho Department of Environmental Quality.
The pilot study report will include:
• Ownership and management information
• Source water background and source water quality information
• Existing treatment and operational practices
• Pilot testing and analytical methodologies
• Pilot testing results, discussion and recommendations
• A basis of design for treatment modifications including:
— Treatment vessel sizing and design criteria
— Media requirements
— Backwashing requirements
— Site planning requirements
— Backwash water disposal, or recycling requirements
— Piping requirements
— Electrical and SCADA requirements
— Building requirements
— Process monitoring and analytical equipment recommendations
• A schedule for design, permitting, approval construction and start-up
• A preliminary order of magnitude cost estimate for completion of the project
Schedule
The first step is to review the pilot testing protocol with the City. The City will notify the
DEQ of the project as a courtesy. The actual pilot testing will require approximately one
week in the field, and preparation of the draft pilot study report will take approximately 1
week to complete. After the City has reviewed the draft we will finalize the report. It is
anticipated that the pilot testing and pilot study report will be completed by the end of
September 2011.
Task Order 10284 Page 4 of 5
Iron and Manganese Pilot Testing
Compensation
The Not -To -Exceed amount for this Task Order No. 10284 is twenty three thousand eight
hundred dollars ($23,800.00). Costs will be billed for actual time services are rendered
plus expenses up to the Not -to -Exceed amount. The hourly rates for services will be
billed at their raw hourly 2011 rate multiplied by a 3.15 multiplier. No compensation will
be paid over the Not -to -Exceed amount without prior written approval by the City in the
form of a Change Order.
CITY OF IIAERIDIA
BY:
KEITIYK, PtVffia ' Manager
Dated: �- ..�-- 6 - I _
Department Ap rova[
BY:
TITLE: ./T'•
Dated:
Task Order 10284
Iron and Manganese Pilot Testing
CH2M HILL
BY: //- � 1/4
MARK BOWEN, V'ce President
Dated:
— 7//1
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