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Regional Desalination Project Test Well Program

Vertical Brackish Source Water Test Well Prepared By: Monterey County Water Resources Agency

March 2011

4.1.E Vertical Test Well Project Description 31Mar11.docx Page 1

Section 1 Introduction

This document describes the construction and operation of a Vertical Brackish Source Water Test Well (vertical test well) and associated clustered monitoring wells proposed as part of the Monterey Bay Regional Desalination Project (Project). In general, the Project is intended to extract a combination of seawater and brackish groundwater from the seawater-intruded 180-Foot Aquifer of the Salinas Valley Groundwater Basin, and treat the water through a reverse osmosis (RO) process to remove the salts (desalination). The Project will be implemented as a partnership among Marina Coast Water District (MCWD), Monterey County Water Resources Agency (MCWRA), and California American Water Company (CAW). MCWRA will own the brackish water intake wells and therefore MCWRA will develop the Project’s Test Well Program that includes construction and temporary operation (including, well development/pump testing, and water quality monitoring, sampling, and analysis) of one (1) vertical and one (1) slant test well and associated clustered monitoring wells. MCWRA is also responsible for obtaining all required permits associated with the test wells.

The vertical test well described herein is being constructed to obtain more precise and actual data concerning the total dissolved solid and chloride levels in the source water, to add to current analyses to provide more information about the effectiveness of the two well types in determining the intake well configuration, to confirm performance of membranes to be used in the desalination plant, and to provide data for determining the optimal location and configuration of permanent source water wells for the Regional Project. The vertical test well will be located on private property approximately one mile north of the City of Marina. An additional test well (with a slant configuration) will also be constructed on a Marina Coast Water District-owned parcel as part of the overall data collection and testing program. Because the objectives and timelines for the two wells are similar to one another, one permit will be sought for both wells.

Once permits are secured, construction of the vertical test well and associated monitoring wells is expected to take approximately two to four months and is scheduled to be initiated in the first quarter of 2011. Additionally, pumping tests of the vertical test well will be conducted over a period of approximately three to six months at an average discharge rate of 2,600 gallons per minute (gpm). During this time approximately 350 to 700 MG (1,075 to 2,150 acre-feet or AF) of groundwater will be extracted and discharged to the ocean through an existing outfall pipe for the wastewater treatment plant (Regional Treatment Plant or RTP), operated by the Monterey Regional Water Pollution Control Agency (MRWPCA). Additional pumping may be required for membrane testing, but only a fraction of the flow will be required for these tests.

The vertical test well will be designed using similar materials, size and construction methodology as the proposed intake wells for the Project. This will ensure that the data collected are representative of the intended intake well field. Further, if the test wells prove successful, they will be re-permitted as permanent wells for supplying source water to the planned RO facility. All testing, analysis, and permanent well permitting will be completed before the wells are converted to and used in any permanent capacity. The current design of the Monterey Bay Regional Desalination Project includes a total of six intake wells.


Section 2 Background The Project is the alternative to the California American Water Company (CAW) Coastal Water Project (CWP) that was selected to be implemented by the CPUC, MCWD, and MCWRA in their relevant project approvals in December 2010, April 2010,1 and January 2011, respectively. Both projects (the CWP and the Project) were evaluated in a project-level Final Environmental Impact Report (FEIR) that was certified December 17, 2009 (State Clearinghouse No. 20066101004). The FEIR is provided on CD in the environmental documentation portion of the Test Well Coastal Development Permit application. The Monterey Bay Regional Desalination Project will supply water to meet the immediate regulatory needs of the Monterey Peninsula and the demands of the former Fort Ord. Specifically, the project will:

Satisfy CAW’s obligations to meet the requirements of SWRCB Order 95-10 to find alternative water sources in order to reduce diversions from the Carmel River;

Diversify and create a reliable drought-proof water supply;

Protect the Seaside Basin for long-term reliability;

Protect listed species in the riparian and aquatic habitat below San Clemente Dam;

Protect the local economy from the effects of an uncertain water supply;

Minimize water rate increases by creating a diversified water supply portfolio;

Minimize energy requirements and greenhouse gas emissions per unit of water delivered to the extent possible;

Explore opportunities for regional partnerships, consistent with the CPUC’s direction in Decision 03-09-0222; and

Avoid duplicative facilities and infrastructure.

In addition to meeting regulatory requirements for water supply, the desalination project will help reduce and remediate seawater intrusion, which is an ongoing water quality issue identified as early as the 1930s.

The Project is a multi-benefit project that is designed to help remediate a local municipal water supply aquifer while contributing to much-needed local water supplies. The raw or source water is intended to be a series of wells located between Highway 1 and the coastal sand dunes, pumping from the seawater-intruded portion of the 180-Foot Aquifer of the Salinas Valley Groundwater Basin. A 10 MGD reverse osmosis (RO) treatment plant located in the North Marina area will reclaim the brackish water and will produce approximately 10,500 AFY of potable water for CAW’s Monterey District service area and MCWD service areas. The distribution facilities for the water produced from the treatment plant include pipelines, storage reservoirs, and pump stations. Power for the RO plant is expected to be provided from a co-generation facility which will use landfill gas as one of its fuel sources. The Project also includes aquifer storage and recovery facilities with a yield of 1,300 AFY which will store desalinated water and Carmel River water in the Seaside groundwater basin during the winter and recover the water for use during peak summer periods.

1 MCWD’s April 2010 approval was conditional upon the CPUC’s approval; therefore, it became final in

December 2010 and MCWD filed their Notice of Determination on January 13, 2011.


This document describes the construction and testing of one of two test wells (the vertical test well) to be constructed for the Project. The two test wells, along with a network of monitoring wells to be constructed at each test well site, will provide the means for collecting necessary data for design of the Project.

Section 3 Vertical Test Well Facilities As previously noted, the vertical test well described herein is being constructed to obtain more precise and actual data concerning the total dissolved solid and chloride levels in the source water, to add to current analyses to provide more information about the effectiveness of the two well types in determining the intake well configuration, to confirm performance of membranes to be used in the desalination plant, and to provide data for determining the optimal location and configuration of permanent source water wells for the Regional Project. The vertical test well will be constructed on private property, approximately one mile north of the City of Marina. Approximately ten (10) clustered monitoring wells (i.e., each well will be constructed in a separate borehole) will be co-located with the vertical test well to provide additional information during test well operation. This section provides additional details regarding the vertical test well site and the proposed well construction.

Vertical Test Well Facilities Location The vertical test well and associated cluster monitoring wells is proposed to be located on two parcels. The first parcel is owned by the CEMEX sand mining operations, located on Lapis Road in the City of Marina. The second parcel is owned by the Armstrong Family (Armstrong Ranch), located adjacent to the CEMEX parcel. Both parcels are located less than a mile north of the western portion of the City of Marina, proper (within the jurisdictional boundaries of the City of Marina), and are shown as a star on Figure 1, below. Use of the property for construction of the test vertical well and associated network of monitoring wells will be based on agreements between MCWRA and CEMEX and between MCWRA and the Armstrong Family. The proposed vertical test well site is approximately 1,000 feet west of Highway 1 (Cabrillo Highway) and is located between the Pacific Ocean (Monterey Bay) and the first public road (Highway 1).


Figure 1 - Site Location Map

The vertical test well and monitoring well sites are located near the eastern (inland) side of coastal sand dunes in a previously disturbed area of the CEMEX property and on Armstrong Ranch. The vertical test well would be located adjacent to structures, including an abandoned house and a shop building (see Figure 2 below).

Figure 2 – Vertical Well Site Photograph (looking East)


The clustered monitoring wells would be located immediately north, east, south, and west of the test well site, on lands surveyed and deemed ruderal/developed and not immediately adjacent to any structure (Figure 3). Public access is not permitted at the site location due to the industrial nature of the site and because it is private property.

Figure 3 - Site Plan

Figure 3 also shows the areas at the project site that may be used for construction and temporary operation of the test well facilities including the test well location, monitoring well locations, staging area and temporary cuttings containment area. These areas range in size from 2,700 square feet (sq.ft.) to 9,000 sq.ft. and are shown in the table below:

Location Approximate Size

(square feet)

Vertical Test Well 8,000

West Monitoring Well Cluster 3,600

East Monitoring Well Cluster 2,700

North Monitoring Well Cluster 2,700

South Monitoring Well Cluster 2,700

Staging and Temporary Cuttings Containment Area 9,000


Access to the site is via Lapis Road, accessed from Del Monte Boulevard in northern Marina.

Description of Surrounding Areas As previously noted, the vertical test well location is located in an area immediately to the east of the dunes. The table below describes the areas surrounding the vertical well test site:

Direction from Site Description

Vertical Test Well Site

The site is located on CEMEX property (private property) that CEMEX currently mines sand from this property. The buildings shown on Figure 3 are a shop and abandoned house. The buried outfall pipeline, owned by MRWPCA, is located immediately adjacent to, and just south of, the test well site, running east to west through an easement south of the CEMEX property.

North Immediately north of the proposed test well site location is agricultural and undisturbed coastal dune lands. This area has no structures.

East The Armstrong Ranch property (private property) occupies the area east of the test well site as far as Highway 1. This area is much like the area north of the test well site, having low vegetation and no structures.

South The Armstrong Ranch property (private property) occupies the area south of the test well site as far as Highway 1. This area is much like the area north of the test well site, having low vegetation and no structures.

West The industrial/sand mining portion of the CEMEX operations and the sand dunes is located west of the site.

Beach Erosion

California Coastal Commission (CCC) requires new developments on coastal bluffs to be sited in such a way that they are not subject to erosion or stability hazard over the course of the design life. The CCC guidelines call for an estimation of bluff edge position projected into the future a minimum of 50 years (CCC-W11.5, Table 2, Point 1, 2003). The anticipated design life of the proposed vertical test well, located at the CEMEX property, is approximately 50 years, which coincides with the CCC 50-year requirement. The CCC guidelines require that the 50-year projected bluff edge is determined by a long-term erosion rate, based on data with a period of record exceeding 50 years. This includes quiet erosional periods (e.g. 1950’s to 1960’s) as well as more erosive periods (e.g., the 1982-1983 and 1997-1998 El Nino events) (CCC-W11.5, Table 2, Point 5, 2003). The long-term erosion rate used to determine the well setback from the bluff edge was calculated in the USGS Open File Report-1251 (2006) and is based on data from 1910 to 2002, satisfying CCC guidelines. To determine an acceptable setback distance for


the location of the test well, a long-term erosion rate of 0.62 meters per year (m/yr), or approximately 2.0 feet per year (ft/yr) as determined by the USGS, was used to establish the minimum set-back distance.

The proposed vertical test well site is located approximately 2,160 feet east of the current shoreline, well in excess of the minimum set-back distance required under the CCC guidelines.

Figure 4 – Long-Term Average Erosional Rates

Ecological Resources Environmental and biological surveys were conducted at and adjacent to the vertical well site during the spring, summer, and fall of 2010. The purpose of the surveys was to assess the environmental conditions of the site and its surroundings, evaluate the general habitat features and environmental constraints within the site and local vicinity, locate and map special-status plants, and provide a basis for recommendations to minimize and avoid impacts to biological resources. The surveys were completed by Denise Duffy and Associates, Inc. (DD&A) biologists, Josh Harwayne, Senior Environmental Scientist, Matthew Johnson, Associate Environmental Scientist, Jami Davis, Assistant Environmental Scientist, and ESA biologist, Martha Lowe. Survey methods included walking the Project’s preliminary site to locate and map special-status plants, habitat for special-status species (where appropriate), general habitat types, and sensitive habitats, including potential wetland resources. Surveys were conducted during the appropriate blooming season for all the special-status plant species identified as having the potential to occur.

In summary, the areas to be impacted by construction of the vertical test well and associated monitoring wells were described as being ruderal or developed, with areas within the southern portion of the site containing low-density Monterey spineflower populations. The site contains habitat for Smith’s blue


butterfly and other special-status wildlife species have the potential to occur. No wetlands were identified on the project site. More detail is provided in the Test Wells Biological Memorandum (DD&A, March 4, 2011).

Vertical Test Well Design and Construction The vertical test well will be drilled to an approximate depth of 350 feet below the ground surface (bgs) in order to access the 180-Foot Aquifer of the Salinas Valley Groundwater Basin and will be designed to produce 2,600 gpm. An up to 30-inch diameter borehole for the vertical test well will be drilled using a dual rotary drilling rig. This drilling methodology was developed for drilling in unconsolidated formations (such as sand, gravel and cobbles). The drilling method does not require the use of drilling fluid additives (i.e. bentonite mud) or other products typically used during the drilling process. The dual rotary drilling method is a proven and accepted method for construction of municipal water supply wells, as well as other types of wells (e.g. monitoring wells for environmental projects) that require specialized drilling methodology.

The vertical test well will be constructed in the borehole following completion with screened intervals to be determined based on field data. The well will be constructed as a municipal water supply well in accordance with both County and State well standards using up to 20-inch diameter casing made of “Super Duplex” Stainless Steel, a specialty metal designed for use in seawater environments. During construction, the casing and screen will be centered in the borehole while an engineered filter pack is placed between the screen and borehole wall. A cement sanitary seal will be emplaced above the filter pack as part of well construction. Following completion, the well will be developed using a combination of bailing, swabbing, air-lifting, surging and pumping until the well has been deemed completed by the field geohydrologist. Surface completion of the test well is described below in Section 3.6.

Further details about the well design are provided in Attachment 1. Well construction and development is expected to take approximately two to four months, and is currently scheduled to occur in early 2011.

Monitoring Well Design and Construction Four clusters (i.e. groups) of monitoring wells will be constructed at the vertical test well site; one cluster will be located east of the test well (on the inland side), one cluster located west of the test well (between the vertical test well and the ocean), and the final two clusters will be located north and south of the test well. Each cluster of monitoring wells will consist of up to four 4-inch diameter monitoring wells with depths ranging from approximately 100 to 420 feet bgs. Boreholes for all monitoring wells will be up to10 ½-inches in diameter, and will be drilled using a sonic drilling method. This method was selected for monitoring well construction as it provides continuous and relatively undisturbed core samples, can be used in a wide range of soil types (i.e., clay, silt, sand, gravel and cobbles), allows for collection of water samples during advancement of the borehole, allows for identification of perched water tables, allows for obtaining geophysical borehole logs, and does not require the use of drilling fluid additives. The monitoring wells will be constructed using 4-inch diameter PVC casing and screen, and will include the use of a filter pack and surface seal in accordance with both County and State well standards for monitoring wells. Further details about the well design are provided in Attachment 1. Monitoring wells will be installed at the beginning of the construction period, with vertical test well construction following, or coinciding with, the end of monitoring well construction.


Following installation, the clusters of monitoring wells will be used to collect groundwater elevation and quality data (i.e. salinity) for use in groundwater modeling. The wells will also be used to monitor groundwater salinity levels during both the test well program and long-term project operations to evaluate the impacts of pumping on water salinity in the immediate vicinity.

To assess whether the pumping test program or Project pumping operations may have an effect on an existing volatile organic compound (VOC) plume located in the former Ft. Ord area, an analysis of vertical test well and Project well pumping on groundwater travel times in two, five, and ten years will be conducted. This analysis will be part of the input data to the Drinking Water Source Assessment and Protection (DWSAP) program documents required as part of the permitting package for the vertical test well and Project intake wells. The purpose of the DWSAP document is to provide information on potential contaminating activities that are within the two, five, and ten year capture zones for a drinking water source. In addition, groundwater modeling will be conducted to assess the potential effects of Project pumping operations on plume migration.

In addition to the monitoring described above, groundwater monitoring will be conducted to determine the potential impacts of intake well pumping (if any) on an existing volatile organic compound (VOC) plume located in the former Fort Ord area, south of the test well sites. Water quality samples will be collected from the existing MCWD-02 well monthly and analyzed for carbon tetrachloride and trichloroethylene, the constituents of concern (COCs) identified in the Fort Ord plume. This well is completed in the 180-Foot Aquifer and is located between the well sites and the VOC plume as seen in Figure 5 below. Data collected as part of the monitoring program will be evaluated in conjunction with water quality data collected by others as part of the plume evaluation and remediation to identify potential plume movement that may be connected with intake well pumping. All wells used in this evaluation are completed in the 180-Foot Aquifer and are located between well sites and the VOC plume as seen in Figure 5 below.

Figure 5 - MCWD Wells for VOC Monitoring


Surface Features The vertical test well will be completed above grade with an integral concrete pedestal surrounding the well. The pedestal will be at least 18-inches above the surrounding grade. The well and pedestal will be surrounded by a larger concrete pad designed to support ancillary piping and utilities. The concrete pad will be surrounded by three foot tall removable bollards or fencing for protection. The above-grade well completion will be screened by existing structures and will not be visible from public access areas/roads. The layout for the vertical test well can be seen in Attachment 1.

During well testing, a pump will be located in the well (either lineshaft turbine or submersible) with above-grade discharge piping and controls. The pump will be powered by electricity from a temporary connection to existing onsite power. Temporary fencing will be placed around the test well site during the testing period to protect equipment and personnel from onsite industrial activities.

The vertical test well will be connected to a new manhole in the MRWPCA outfall. Backflow prevention devices will be placed on the pipeline to prevent the potential backflow of treated wastewater effluent into the well.

Monitoring wells at the site will be completed either above grade with a locking standpipe set into a poured concrete pad, or set at grade with a traffic-rated flush cover, or “Christy” box. For above-grade completions, the two- to three-foot high locking standpipe and pad will be protected by bollards placed around the pad.

Section 4 Vertical Well Testing Program

Test Well Program Objectives As noted above, the vertical test well program is necessary to collect required data for design of the Project. Specifically, the test vertical well program will:

Determine optimal pumping rates and confirm long-term sustainable production rates for future permanent intake wells.

Provide additional, site-dependent data on the hydrogeologic and hydraulic properties of the groundwater basin in the vicinity of the test well for use in the project groundwater model, including but not limited to transmissivity, storativity, zone of influence, specific capacity and hydraulic conductivity.

Collect water quality data required to design the desalination facility, to characterize the intake water quality (for the purpose of both feedwater to the desalination plant, and well construction/development and testing period water disposal during the test period), and to model the brine water quality.

Gain additional understanding of the long-term sources of water to the wells, especially with respect to differentiating between “inland groundwater” and seawater.

In order to provide the best data possible for the project design, the test well has been designed and will be constructed in a manner and size similar to the design and construction of of the proposed final intake wells.


Following well completion, the vertical test well will be pumped for a period between three and six months at approximately 2,600 gallons per minute. Water produced during the testing period will be discharged into the MRWPCA outfall. Both groundwater elevation and water quality monitoring and sampling will occur over the testing period. A summary of the monitoring program that will be conducted as part of the pumping test program is presented below.

Management of Drill Cuttings Lithologic cuttings generated during the drilling process will be placed in above-grade containers at the staging and temporary cuttings containment area. The drill cuttings will be allowed to drain, with water discharged to the ground. Drainage at the tank location will be managed such that all water stays onsite, with no soil erosion or ponding occurring and with all dewater percolating back into the ground. Dewatered drill cuttings will be hauled to the Monterey Regional Waste Management District (MRWMD) landfill for disposal; an estimated 15 to 30 cubic yards of soil will be managed onsite at any given time.

Groundwater produced during drilling, well construction, and the early phases of vertical test well and monitoring well development is expected to contain sediment and will be pumped into temporary above-ground tanks located in the work area or staging/temporary cuttings containment area. An estimated total volume of 130,000 gallons of water containing sediment may be produced. Once pumped into the temporary above-ground tanks, the sediment will be allowed to settle to reduce the turbidity of the water to a level less than 75 NTUs. Once the desired turbidity level is reached, the dewater will be decanted and drained to ground and/or pumped to an outlet in the adjacent MRWPCA outfall (depending on volume). Sediments that remain in the tanks will be drained and hauled to the MRWMD landfill.

During the final phases of well development and during the pumping test program, it is expected that the groundwater discharged from the vertical test well and monitoring wells will have acceptable levels of turbidity to be discharged directly to the MRWPCA outfall. Approximately 350 to 700 MG of groundwater is estimated to be extracted during this period of time.

Best Management Practices (BMPs) will be employed during all drill cuttings and fluid containment activities to prevent sediment and water runoff to adjacent areas. Details regarding drill cuttings management and BMP deployment will be documented in a Stormwater Pollution Prevention Plan (SWPPP) developed for the site.

Discharge of Test Well Water As noted above, water pumped from the test well will be discharged to Monterey Bay through the existing MRWPCA outfall. MRWPCA’s discharge through the outfall is permitted under Waste Discharge Requirement (WDR) issued by the Central Coast RWQCB (Order No. R3-2008-0008, NPDES No. CA0048551). Discharge of water will occur during the spring and summer months when the MRWPCA minimally uses the outfall (all influent during these times undergoes tertiary treatment and is then used for agricultural irrigation). Further details about the discharge water and the outfall are provided below.

Description of Discharge and Constituents The vertical test well is expected to produce approximately 350 to 700 MG (1,075 to 2,150 AF) during construction and over the three to six month aquifer pumping test period. A sampling program for the


vertical test well discharges will be implemented as previously described, but water quality data from a nearby existing monitoring well (DMW-2), screened in the 180-Foot Aquifer, provides a good indication of the expected water quality from the test well. This monitoring well is located at the MCWD office at the end of Reservation Road, approximately one mile south of the vertical test well site (Figure 6). The monitoring well was originally drilled as part of a monitoring program for a former MCWD desalination pilot facility and has been tested for a wide range of constituents. Evaluation of the test results indicates that groundwater in the vicinity of DMW-2 is essentially equivalent to the water quality of seawater and that no contaminants are present.

Figure 6 - Monitoring Well DMW 2 Location

Analytical results of samples from DMW-2 are compared to water quality criteria as contained in MRWPCA’s NPDES permit for the outfall; this analysis is provided in Attachment 3.

Source of Discharge

All discharges associated with the test well project will originate from either the vertical test well or the adjacent clustered monitoring wells. While the bulk of the discharges will be produced during the three to six month pump testing period, some water will be discharged during the construction and development of the vertical test well and monitoring wells. Because water from the construction and initial development of any of the wells may have some level of sediment, this water will be managed differently than the pumping test waters that will be discharged directly to the outfall. A summary of the sediment management strategies during different phases of the project is provided below and is discussed in Section 4.2, above. All flows discharged to the MRWPCA outfall will be metered and recorded to determine actual discharge volume. Further, all samples will be analyzed for the following suite of tests, unless otherwise noted in the sections below. The Test Well Program sampling and analysis program is included in the monitoring portion of the Test Well Coastal Development Permit application.


Parameter Method Parameter Method

General Organics

Carbonaceous BOD5 SM 5210 Oil & Grease SM 5520 B

TSS SM 2540 D Phenolic Compounds SM 5530 D

Settable Solids SM 2540 F Endosulfan EPA 525.2

Turbidity SM 2130 Endrin EPA 505

pH SM 4500 H+B HCH EPA 608

Inorganics Acrolein EPA 603

Arsenic EPA 200.8 Bis(2-chloroethoxy) methane EPA 611

Cadmium EPA 200.8 Bis(2-chloroisopropyl) ether EPA 611

Hexavalent Chromium EPA 218.6 Chlorobenzene EPA 524.2

Copper EPA 200.8 Di-n-butyl phthalate EPA 525.2

Lead EPA 200.8 Dichlorobenzenes EPA 524.2

Mercury EPA 245.1 Diethyl phthalate EPA 525.2

Nickel EPA 200.8 Dimethyl phthalate EPA 525.2

Selenium EPA 200.8 4,6-dinitro-2-methylphenol EPA 604

Silver EPA 200.8 2,4-Dinitrophenol EPA 604

Zinc EPA 200.8 Ethylbenzene EPA 524.2

Cyanide EPA 335.4 Fluoranthene EPA 525.2

Total Residual Chlorine SM 4500-Cl E Hexachlorocyclopentadiene EPA 525.2

Ammonia (as N) EPA 350.1 Nitrobenzene EPA 524.2

Antimony EPA 200.8 Toluene EPA 524.2

Chromium (III) EPA 200.8 Tributylin EPA 282.3

Thallium EPA 200.8 1,1,1-Trichloroethane EPA 524.2

Biological Acrylonitrile EPA 524.2

Acute Toxicity EPA 821-R-02-012 Aldrin EPA 505



Chronic Toxicity EPA 821-R-02-013 Benzene EPA 524.2

Total Coliform SM 9222 B Benzidine EPA 605

Fecal Coliforms SM 9222 D Beryllium EPA 200.8

Enterococcus SM 9230 B Bis(2-chloroethyl) ether EPA 611

Bis(2-ethylhexyl) phthalate EPA 606

Carbon Tetrachloride EPA 524.2

Chlordane EPA 505

Chlorodibromomethane EPA 524.2

Chloroform EPA 524.2

DDT EPA 525.2

1,4-dichlorobenzene EPA 524.2

3,3-Dichlorobenzidine EPA 605

1,2-Dichloroethane EPA 524.2

1,1-Dichloroethylene EPA 524.2

Dichlorobromomethane EPA 524.2

Dichloromethane EPA 524.2

1,3-Dichloropropene EPA 524.2

Dieldrin EPA 608

2,4-Dinitrotoluene EPA 525.2

1,2-Diphenylhydrazine EPA 526

Halomethanes EPA 524.2

Heptachlor EPA 505

Hetachlor Epoxide EPA 505

Hexachlorobenzene EPA 505

Hexachlorobutadiene EPA 524.2



Hexachloroethane EPA 524.2

Isophorone EPA 525.2

N-nirtosodimethylamine EPA 521

N-nitrosodi-N-propylamine EPA 521

N-nitrosodiphenylamine EPA 521

PAHs EPA 525.2

PCBs EPA 505

TCDD equivalents EPA 1613

1,1,2,2-Tetrachlorethane EPA 524.2

Tetrachloroethylene EPA 524.2

Toxaphene EPA 608

Trichloroethylene EPA 524.2

1,1,2-Trichloroethane EPA 524.2

2,4,6-Trichlorophenol EPA 526

Vinyl Chloride EPA 524.2

Discharge During Well Construction

Approximately 20,000 gallons of water will be discharged during vertical test well and monitoring well construction. All waters produced during this portion of the field project will be temporarily held in tanks prior to disposal to allow sediment to settle out of the water column. Clarified water will be decanted from the temporary holding tanks and pumped to the MRWPCA outfall. The remaining solids will then be dewatered prior to offsite disposal. Water quality samples will be collected for analysis at the outlet of the temporary holding tanks during the initiation of disposal to the outfall and at the completion of disposal to the outfall. Sampling will be performed on a weekly basis during the discharge period.


Discharge During Well Development

The purpose of well development is to ensure removal of fines from the well screen, filter pack, and near-well zone of the aquifer. The vertical test well and monitoring wells will be developed by a combination of bailing, air lifting, surging and pumping. An estimated 110,000 gallons of water will be extracted during the initial portion of well development. During the initial development periods, water extracted from the well may have elevated suspended sediment levels. These waters will be treated similar to waters extracted during well construction (i.e. settled prior to disposal), including water quality sampling and analysis. Once well pumping is instigated as part of the development program, extracted water will be discharged directly to the MRWPCA outfall.

Later stages of well development are anticipated to produce little to no sediment; and therefore water will be discharged directly to the MRWPCA outfall. An estimated volume of 8 MG of water will be extracted during this later well development period will be directed to the outfall for discharge. Water samples will be collected for analysis at the start of the well development program and weekly during the development period.

Discharge During Vertical Test Well Testing

Waters extracted during the three- to six-month pumping test period is expected to have little to no sediment load and water quality very similar to seawater. An estimated volume of 350 to 700 MG will be produced during this pumping test phase. These waters will be discharged directly to the MRWPCA outfall (Attachment 2), with biweekly sampling of the discharge to ensure conformance with permit requirements.

Summary of Sampling Plan

All samples collected from the vertical test well during the testing program will be grab samples from the well head. Additional samples may be collected from the adjacent monitoring wells and holding tanks or clarifiers these samples will be collected via bailers, submersible pump and/or peristaltic pump. Samples will be analyzed for the suite of constituents shown in Section 4.3.2, following the procedures and protocols established in the Test Well sampling and analysis plan.

In general, all samples will be collected in plastic or glass bottles (determined by analysis), stored out of direct sunlight in a cooler and on ice, and will be held at a temperature of at 4oC. Samples will be logged in the field, recorded on a Chain of Custody form and sent to a California-certified analytical laboratory for analyses. In addition, water temperature, specific conductance (EC), dissolved oxygen (DO) and pH analyses will be measured directly in the field at the time of sampling.

Attachments

1. Vertical Test Well Drawings 2. Outfall Pipeline Access Drawing 3. Comparison of DMW-2 Sample Data to MRWPCA NPDES Permit Conditions

4.1.E Vertical Test Well Project Description 31Mar11.docx

Attachment 1 – Vertical Test Well Site Drawings

ralameda

Text Box

90% Drawings


Attachment 2– Outfall Pipeline Access Drawing

OUTFALL PIPELINE ACCESSPLAN, PROFILE, SECTION AND DETAIL

DWG NO

SHEET NO

PROJ NO

DATE

PRELIMINARY

DESIGN

ralameda

Text Box

90% Drawings


Attachment 3 – Comparison of DMW-2 Sample Data to MRWPCA NPDES Permit Conditions


Comparison of DMW-2 Data with MRWPCA NPDES Permit

Parameter Units

Ave

Monthly

Ave

Weekly

Max

Daily DMW‐2 Method No.

CBOD5 mg/L 25 40 85 SM 5210

TSS mg/L 30 45 90 SM 2540 D

Settable Solids mg/L 1 1.5 3 SM 2540 F

Turbidity NTU 75 100 230

0.11 ‐

0.21 SM 2130

Oil & Grease mg/L 25 40 75 SM 5520 B

pH unitless 6.0 to 9.0 at all times 6.6 ‐ 6.8 SM 4500 H+B

Parameter Units

6‐Month

Median

Daily

Maximum

Instantaneous

Maximum DMW‐2

Arsenic �g/L 733 4,237 11,245 <5 ‐ 22 EPA 200.8

Cadmium �g/L 146 584 1,460

<2.5 ‐

4.6 EPA 200.8

Hexavalent Chromium �g/L 292 1,168 2,920 EPA 218.6

Copper �g/L 148 1,462 4,090 <10 ‐ 22 EPA 200.8

Lead �g/L 292 1,168 2,920

<2.5 ‐

3.7 EPA 200.8

Mercury �g/L 5.7675 23.2875 58.3275 <0.2 EPA 245.1

Nickel �g/L 730 2,920 7,300 <2.5 EPA 200.8

Selenium �g/L 2,190 8,760 21,900

<2.5 ‐

32 EPA 200.8

Silver �g/L 79 385.6 998.8

<0.5‐

4.9 EPA 200.8

Zinc �g/L 1,760 10,520 28,040 <20 ‐

EPA 200.8


<100

Cyanide �g/L 146 584 1,460 <5 EPA 335.4

Total Residual

Chlorine �g/L 292 1,168 8,760 SM 4500‐Cl E

Ammonia (as N) �g/L 87,600 350,400 876,000 <50 EPA 350.1

Acute Toxicity �Ua ‐‐ 4.65 ‐‐ EPA 2000

Chronic Toxicity �uc ‐‐ 146 ‐‐

EPA 821‐R‐02‐

013

Phenolic Compounds �g/L 4,380 17,520 43,800 SM 5530 D

Endosulfan �g/L 1.314 2.6328 3.942 EPA 525.2

Endrin �g/L 0.292 0.584 0.876 <0.01 EPA 505

HCH �g/L 0.584 1.168 1.752 EPA 608

Radioactivity Not to exceed limits in Title 17, Division 1, Chapter 5,

Subchapter 4, Group 3, Article 3, Section 30253 of the

CCR

Parameter Unit

30‐day

Average DMW‐2

Acrolein g/L 32,120 EPA 603

Antimony g/L 175,000 < 9.6 EPA 200.8

Bis(2‐chloroethoxy) methane g/L 642.4 EPA 611

Bis(2‐chloroisopropyl) ether g/L 175,000 EPA 611

Chlorobenzene g/L 83,220 EPA 524.2

Chromium (III) g/L 27,740,000 EPA 200.8

Di‐n‐butyl phthalate g/L 511,000 <1.0 EPA 525.2

Dichlorobenzenes g/L 744,000 EPA 524.2


Parameter Unit

30‐day

Average DMW‐2

Diethyl phthalate g/L 4,818,000 <0.5 EPA 525.2

Dimethyl phthalate g/L 119,720,000 <0.5 EPA 525.2

4,6‐dinitro‐2‐methylphenol g/L 32,120 EPA 604

2,4‐Dinitrophenol g/L 584 EPA 604

Ethylbenzene g/L 598,600 <0.5 EPA 524.2

Fluoranthene g/L 2,190 <0.1 EPA 525.2

Hexachlorocyclopentadiene g/L 8,468 <0.05 EPA 525.2

Nitrobenzene g/L 715.4 EPA 524.2

Thallium g/L 290 <5 EPA 200.8

Toluene g/L 12,410,000 <0.5 EPA 524.2

Tributylin g/L 0.2044 EPA 282.3

1,1,1‐Trichloroethane g/L 19,500,000 <0.5 EPA 524.2

Acrylonitrile g/L 14.7 EPA 524.2

Aldrin g/L 0.003212 <0.01 EPA 505

Benzene g/L 861.4 <0.5 EPA 524.2

Benzidine g/L 0.010074 EPA 605

Beryllium g/L 4.818 <4 ‐ <5 EPA 200.8

Bis(2‐chloroethyl) ether g/L 6.57 EPA 611

Bis(2‐ethylhexyl) phthalate g/L 511 EPA 606

Carbon Tetrachloride g/L 131.4 <0.3 EPA 524.2

Chlordane g/L 0.003358 <0.1 EPA 505

Chlorodibromomethane g/L 1,256 <0.5 EPA 524.2


Parameter Unit

30‐day

Average DMW‐2

Chloroform g/L 18,980 <0.5 EPA 524.2

DDT g/L 0.02482 EPA 525.2

1,4‐dichlorobenzene g/L 2,628 <0.5 EPA 524.2

3,3‐Dichlorobenzidine g/L 1.1826 EPA 605

1,2‐Dichloroethane g/L 4,090 <0.5 EPA 524.2

1,1‐Dichloroethylene g/L 131.4 <0.5 EPA 524.2

Dichlorobromomethane g/L 905 EPA 524.2

Dichloromethane g/L 65,700 <0.5 EPA 524.2

1,3‐Dichloropropene g/L 1,299.4 <0.5 EPA 524.2

Dieldrin g/L 0.00584 <0.002 EPA 608

2,4‐Dinitrotoluene g/L 379.6 <0.1 EPA 525.2

1,2‐Diphenylhydrazine g/L 23.36 EPA 526

Halomethanes g/L 18,980 <1.5 EPA 524.2

Heptachlor g/L 0.0073 <0.01 EPA 505

Hetachlor Epoxide g/L 0.0029 <0.005 EPA 505

Hexachlorobenzene g/L 0.03066 <0.05 EPA 505

Hexachlorobutadiene g/L 2,044 <0.05 EPA 524.2

Hexachloroethane g/L 365 EPA 524.2

Isophorone g/L 106,580 <0.05 EPA 525.2

N‐nirtosodimethylamine g/L 1,065.8 <0.002 EPA 521

N‐nitrosodi‐N‐propylamine g/L 55.5 <0.002 EPA 521

N‐nitrosodiphenylamine g/L 365 <0.002 EPA 521


Parameter Unit

30‐day

Average DMW‐2

PAHs g/L 1.2848 <1.44 EPA 525.5

PCBs g/L 0.002774 <0.68 EPA 505

TCDD equivalents g/L 5.694E‐07 EPA 1613

1,1,2,2‐Tetrachlorethane g/L 335.8 <0.5 EPA 524.2

Tetrachloroethylene g/L 290 <0.5 EPA 524.2

Toxaphene g/L 0.03066 <0.5 EPA 608

Trichloroethylene g/L 3,942 <0.5 EPA 524.2

1,1,2‐Trichloroethane g/L 1,372 <0.5 EPA 524.2

2,4,6‐Trichlorophenol g/L 42.34 EPA 526

Vinyl Chloride g/L 5,256 <0.3 EPA 524.2

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