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HomeMy WebLinkAboutTri-area Ground Water Study TABLE OF CONTENTS Page Executive Summary ......................................................... 3 Int d ti ..... 1.0 ro uc on ....................................................... 3 2.0 Project Description ...................................................... 2.1 Project Background 2.2 Objectives 2.3 Project Rationale 3.0 Physical Setting 3.1 Construction of the Sparling Well 3.2 Physical Setting 3.3 Brief Glacial History of the Quimper Peninsula 3.4 Site Geology 3.5 Surface Water 4.0 Summary of Field Program ............................................... 4.1 Drilling Program 4.2 Groundw_ ater Elevation Measurements 4.3 Hydrogeology of Project Area -- 4.4 Water Quality Testing 16 5.0 Aquifer Test ...... : .................... '~ .............................. 5.1 Methods 5.2 Special Considerations 5.3 Analysis Methods 5.4 Aquifer Test Results 5.5 Aquifer Test Conclusions 31 6.0 Water Balance Estimates of Aquifer Recharge ................................ 36 6.1 Basin-Wide Analysis 6.2 Sparling Vicinity Recharge Analysis Summary and Conclusions ............................................... 7.1 Summary of Hydrogeology 7.2 Predicted Aquifer Yield 7.3 Risk of Seawater Intrusion 7.4 Potential Impact on Chimacum Creek 40 7.0 A:\SUMFINL.TRI 9/6/96 8.0 Recommendations ...................................................... 8.1 New Production Well Location 8.2 New Production Well Specifications 8.3 Water Quality of New Production Well 8.4 Ongoing Monitoring Program 8.5 Aquifer Protection Measures LIST OF FIGURES Figure 1 Tri-Area Vicinity Map Figure 2 Site Area Map Figure Figure Figure Figure 5 Figure 6 Figure 7 Figure 8 Figure Figure Figure Figure 3 Geology of Tri-Area 4 Maximum Extent of Glacier During Vashon Stade of Fraser Glaciation 4A Lake Leland Section 3 Map Showing Monitoring Well Locations Log of Boring MW-1 Log of Boring MW-2 Log of Boring MW-3 9 Log of Sparling Well 10 Hydrogeologic Cross-Section of Project Area 11 Aerial Photos of Project Area 12 Preliminary-Aquifer Recharge Areas LIST Table 1 Table 2 Table 3 Table 4 Table 5 Table 6 Table 7 OF TABLES City of Port Townsend Groundwater Wells Description of Geologic Units Well and Groundwater Elevations Analytical Test Results Water Level Measurement Interval Calculated Aquifer Parameters Surface Area of Recharge Zones APPENDICES A. Work Plan B. References C. Well Numbering Scheme D. Summary of Well Logs Compiled for this Study E. Monitoring Well Construction Details F. Analytical Laboratory Reports G. Aquifer Test Data Collection Sheet H. Well Hydraulics Equations I. Aquifer Test Plots 41 A:\SUMFINL. TRI 9/6/96 Executive Summary This report describes the results of a groundwater study in the Sparling well vicinity performed by CH2M HILL for the City of Port Townsend. The City relies on the Sparling well as the main source of supply for the Tri-Area Service Area. Improving the capacity and reliability of the Spading well and treatment system has been identified as a high priority in the City's water system Capital Improvements PrOgram. In 1995, CH2M HILL prepared an evaluation of the well and treatment system and recommended a multi- year program to expand the treatment capacity and install a new Spading well. Treatment system improvements should be on-line by the first of the year. The purpose of this groundwater study was to estimate the potential yield of a new groundwater production well. In addition, the study evaluated the impact of_pumping on Chimacum Creek and the potential for seawater intrusion. The study also provided data that will be useful in delineating wellhead protection areas. In performing this study, three monitoring wells were installed. Data on the geology of the area were collected prior to and during drilling of these wells. The yield of the aquifer was estimated by-performing an aquifer test o1~ the existing Spading well and measuring water levels in the monitoring wells and other nearby wells. During the course of this study, it was determined that the Sparling well draws water from one primary aquifer, designated herein as the Sparling Aquifer, which is a confined aquifer within the Advance Outwash unit. Groundwater flow is to the northeast in the Sparling Aquifer. The aquifer has a very high transmissivity, which is its ability to transmit water. The aquifer recharge area appears to be to the west and south of the Spading well, encompassing at least a portion of the Anderson Lake Upland. It is estimated that the Sparling well has an annual recharge rate of at least 940 gallons per minute (gpm) [1.35 MGD (million gallons per day)]. Conclusions The following conclusions were reached based on the investigation and aquifer tests that were part of this study: 1) Because of age and construction, the Sparling well efficiency is low, approximately 40 percent. 2) A new production well could produce at least 1000 gpm based on the transmissivity of the aquifer. Well production will be limited by the amount of water which recharges the aquifer, if it is not to be overpumped. Recharge to the Sparling Aquifer was estimated conservatively at 940 gpm. 3) Two production wells could be located within about 300 feet of each other with minimal interference during pumping, assuming no other major impermeable boundaries are encountered which weren't apparent during the aquifer test. A:\SUMFINL.TRI 1 9/6/96 _ 4) The water quality in a new well will be similar to the water quality in the Sparling well and will require treatment for iron and manganese. 5) The risk of seawater intrusion to the Spading Aquifer in response to pumping in the Spading vicinity appears to be negligible at the anticipated pumping rate. 6) The Sparling Aquifer is not in direct hydraulic continuity with Chimacum Creek. Recommendations ..: As a result of the study, we have the following recommendations for the City: 1) Install a new 16-inch production well in the Spading Aquifer. We anticipate it will produce a minimum of 1000 gpm of groundwater, enough to produce the appropriated groundwater right on an annual basis. The well should be located as close as possible to the Sparling well to increase the likelihood of it being a high capacity well. If the new well and the Sparling well are intended to be pumped simultaneously, the new well should be located at least 200 to 300 feet from the Sparling well. If only one well is to be pumped at a time, this distance is not necessary. 2) Establish an ongoing aquifer monitoring program to help develop a better understanding of the Sparling Aquifer, including: · Measure groundwater levels on a monthly basis in monitoring wells MW-l, -2, and -3, well 3K-2 (Spigarelli well), and the Spading well; and -' · Conduct an aquifer test using the new well after it is installed. 3) Initiate an aquifer or wellhead protection program to protect the Sparling Aquifer and wells. The following are key steps in that process: · Design_ate wellhead protection areas for the well. An initial map of recharge areas is presented in this report (Figure 12); work should be done to further define the-- areas and designate ~ime-of-travel zones. · Take action to minimize potential contaminant sources in the recharge or wellhead protection areas. · Initiate a public education campaign regarding groundwater. Education is an effective tool in protecting vulnerable groundwater resources. A:\SUMFINL. TRI 2 9/6/96 I.-0 Introduction This Report summarizes work conducted by CH2M HILL for the City of Port Townsend, Department of Public Works. CH2M HILL was retained by the City to conduct a study of groundwater in the Tri-Area of Jefferson County, Washington. The aim of the study was to assess the area hydrogeology and recommend a location for a new groundwater-production well. This report presents background information, reviews activities conducted for the study, summarizes results, and presents recommendations. ~ 2.0 Project Description 2.1 Project Background The City of Port Townsend supplies water to users in the Port Townsend and Tri-Area vicinities of Jefferson County (Figures 1 and 2). Tri-Area refers to the vicinity encompassing the towns of Chimacum, Hadlock and Irondale. Water supplies are currently obtained through a combiri'ation of surface water and groundwater sources. To meet the requirements of the Safe Drinking Water Act, groundwater will become the primary source of supply to the area, with surface water providing only emergency backup. The surface water supply does not meet the CT requirements of the Surface Water Treatment Rule. The City possesses water rights for and Currently produces from two groundwater production wells located in the Tri-Area. These wells are known as the Spai:ling and the Kivley Wells. The well locations are shown in Figure 2. In order to meet current and projected water use, the City of Port Townsend must increase its production capability of groundwater utilizing the existing water right. The City has groundwater rights for the Sparling and Kivley wells, as outlined in Table 1. Current usage and treatment capacity are also shown. TABLE I : CITY OF PORT TOWNSEND GROUNDWATER WELLS Source Right: Average Right: Peak Current Well Current Annual Flow Day (GPD) Capacity Treatment (GPD) (GPD) Capacity (GPD) Sparling Well 999,803 3,240,000 800,000 800,000 Kivle¥ Well 142,829 288,000 100,000 0 TOTAL 1,142,632 3,528,000 900,000 800,000 A:\SUMFINL.TRI 9/6/96 Current Sparling well production is approximately 800,000 gallons per day (GPD). This is apl~roximately 2,400,000 GPD less than the peak day water right. The City has applied to the Department of Ecology (Ecology) for an additional point of diversion to fully utilize, or perfect, this right, ff granted, this would enable the City to pump water from another well located in the same source unit in order to achieve the total production allocated in the original water right. 2.2 Project Objectives ": The objectives of the current project were to recommend the location and depth for a new groundwater production well and to estimate its potential yield. Other objective~ were to evaluate the probable impact of pumping on Chimacum Creek as well as the potential for seawater intrusion. The study was also designed to estimate the water quality of a potential new well and to provide geological data which would be useful in delineating wellhead protection areas. 2.3 Project Rationale Study Location The Sparling well vicinity is considered to be one of the.best potential locations for a new production well for the following reasons: 1. The City already possesses a water right for the Sparlin_g well. A new well installed in the same production zone-as the Spading well could utilize the same water right, if Ecology were to grant an additional point of diversion. The closer an additional point of diversion is to the Sparling well, the easier it will be to show it is the same unit, thus simplifying water rights issues. 2. The Sparling well is one of the most productive wells in Jefferson County. A new production well in the vicinity would likely also be highly productive; and, 3. It is located in the middle of the Quimper Peninsula, in an area where bedrock appears to form a natural barrier against seawater intrusion. For these reasons, the current groundwater study focuses on conditions near the Sparling well. Study P, ctivities In order to assess the extent and potential yield of aquifers in the Sparling well vicinity, the following activities were conducted: 1. Drilled and logged three boreholes; 2. Installed three monitoring wells; 3. Measured water levels in monitoring wells and other nearby wells; and, 4. Conducted an aquifer test using the existing well and the monitoring wells. In addition, to evaluate the water quality of the potential production well, water samples were collected and analyzed for iron, manganese, fecal coliform, and total organic carbon. The procedures and methods used to implement these activities are outlined in detail in the March 19, 1996 Work Plan, presented in Appendix A. A:\suMFiNL.TRi 4 9/6/96 3.-0 Physical Setting The information presented in this section was compiled from geologic reports, geologic maps, aerial photos and logs of wells. In addition, new information derived from this investigation has been incorporated into the geologic description. An attempt has been made to present the information in a manner that is understandable to non-geologists. Full references are cited in Appendix B. The well numbering scheme is based on township, range, section, quarter section, and quarter-quarter section. It is the same system employed by the U.S. Geological Survey, Washington Department of Ecology (Ecology), Washington Department of Natural Resources, and others. It is described in Appendix C. The well log information compiled by the Jefferson County Water Resources Committee uses a compatible and nearly identical system. Well logs compiled for this study are summarized in a spreadsheet in Appendix D. 3.1 Construction of the Sparling Well The Sparling well, the existing pumping well, was drilled in February 1956. The driller's log filed at that time indicates the well was drilled to a depth of 184 feet and a twelve-inch diameter well casing installed. Th~ yield estimated at that time was 720 gpm (gallons per minute). The well was reconditioned in the 1970s. At that time, a ten-inch casing was installed inside the well. A Mar~ch, 1995 videotape of the inside of the well shows that the ten-inch casing extends from the bottom of the well to a depth of approximately 64 feet. That video also shows three screened intervals, at ~he following depths: 75-80 feet, 92 - 123 feet, and 157-169 feet. These intervals are indicated on the log of the Sparling well (Figure 9). The screened portions of the well, as seen in the video, are visibly corroded. The bottom of the well, below about 175 feet, is filled with sediment. The pump intake is currently located at a depth of about 120 feet. 3.2 Physical Setting The Tri-Area, including the project site, is located approximately nine miles south of Port Townsend on the Quimper Peninsula in eastern Jefferson County (Figures 1 and 2). It is on the west side of the Chimacum Valley which is bounded by uplands to the east and west. About two miles south of the project site, West Valley forks to the west from Chimacum Valley. The Quimper Peninsula itself is a spur extending into Puget Sound from the northeast corner of the Olympic Peninsula. This positioning played a key role in shaping the landscape and geologic deposits found there (Figure 3). The occurrence of groundwater and aquifers on the Quimper Peninsula is likewise controlled by the glacial history: Thus, in order to give the reader a context for the groundwater study, a brief glacial history is presented below. 3.3 Brief Glacial History of the Ouimper Peninsula The landscape of the Quimper Peninsula, like most of Washington, was formed during the Ice Age by the massive glaciers of the Pleistocene. During the Pleistocene, some 45,000 to 12,000 years ago, a colossal ice sheet covered much of Canada and the northern regions of the present day U.S. In addition, cordilleran or mountain glaciers occupied the mountainous regions in the west. These glaciers advanced southward periodically, in response to climatic and other changes. A:\SUMFINL.TRI 8 9/6/96 Miles thick in places, the glaciers dramatically altered the landscape where they passed. In fact, thePuget Lowland, site of present-day Puget Sound, was gouged to a depth of nearly 950 feet below present-day sea level by glaciers (Crandell and others, 1965). The most recent glacial advance on the Quimper Peninsula is known as the Fraser Advance (named after the river in British Columbia). During the Fraser, one lobe of the glacier extended into the Puget Lowland, and another into the Strait of San Juan de Fuca. The Fraser glaciation is sub-divided into glacial episodes, or stades. During a stade, the ice would advance, then retreat or melt back until the next stade. The ice reached its maximum extent during the most recent advance, the Vashon Stade, when it extended south of Olympia and west to the'~Olympic Mountains, as shown in Figure 4. As a glacier moves across the land, it has the effect of leveling the landscape, eroding hills and crags. As these features erode, they become incorporated into the ice as rock fragments. At the same time, the ice in the glacier melts from exposure to sun and the warmth of the earth, and rivers flow from the glacier, carrying with them a tremendous load of sand, silt, and other deposits. During the Vashon Stade, which began in this area about 15,000 years ago according to radiocarbon dates, the climate was cooler than it is today. Bogs and spin_ce forests dotted the landscape. As the ice advanced southward, it blocked Admiralty Inlet, trapping water in the Puget Lowland to create a giant ice-dammed lake (Thorson, 1981). At the same time, braided rivers flowed from the front of the glacier depositing sands, gravels, and silts. The deposits were reworked as the glacier continued advancing southward. The unit formed as the glacier advanced is known as the Adwance Outwash. It is comprised of gray silts and clays on the bottom, with gray sands and gravels in the upper part. This formation is the most prolific water-bearing formation in the area. As the ice continued advancing, at the rate of about one mile every ten years (Mullineaux and others, 1965), it eventually rode over the Advance Outwash. When the ice was actually atop the land, it deposited a dense mixture of coarse gravel and silt, known as the Vashon Lodgement Till, which was subsequently compressed by the weight of the glacier. During its maximum extent, the glacier filled the Puget Basin to a depth of at least 4000 feet. When conditions changed, the glacier began melting back. The ice margin retreated northward as the stagnant ice melted. It continued dropping its sediment load as till. The new landscape was exposed as the glacier melted away. Sediments known as Recessional Deposits were laid down by rivers flowing from the front of the glacier. On the Quimper Peninsula, some recessional deposits were emplaced on land and some in the sea, in a submarine environment. In many locations, till was eroded and redeposited as part of the recessional deposits. As the ice margin retreated, a series of ice-dammed lakes formed with their borders moving successively northward (Thorson, 1981). A lake would form south of the ice margin, then after the ice melted sufficiently to compromise the ice dam, it would burst and the lake waters would flow away. The next lake would then form farther north. The last lake, and the only one which extended as far north as the Tri-Area, is known as Lake Leland (Figure 4A). At that time the glacier margin was barely north of the project site. Ice covered the Quimper A:\SUMFINL. TRI 9 9/6/96 Peninsula north of Four Comers Road and the highway to Hadlock. Lake Leland filled West and Chimacum Valleys, while the surrounding hills were islands in the lake. Indian legends about Tamanous Rock, located approximately one mile south of the project site, may relate to Lake Leland. According to the story, there was a great flood a long time ago. The people of the area went to the rock to wait out the flood in their canoes. After the flood waters dissipated, the people went out in their canoes and settled the Puget Sound area. Because of the proximity of Tamanous Rock to the northern end of the Quimper Peninsula and. Admiralty Inlet, the flood mentioned in the legend may well correspond with the draining of Lake Leland, the last ice-dammed lake of the Ice Age in this area. Radiocarbon dates indicate the en-d. of this period occurred about 12,000 years before present. The materials beneath the deposits of the Vashon Advance have not been well-characterized on the Quimper Peninsula. They are a mixture of materials from the non-glacial interval preceding · the Fraser glaciation, undifferentiated deposits of previous glacial advances, and bedrock. Bedrock in this vicinity is comprised of Tertiary volcanics and sedimentary rocks. It is exposed in the bluffs east of Anderson Lake, including Tamanous Rock. 3.4 Site Geology In the Sparling well vicinity, the bedrock upland where Anderson L~ake is located exerted a controlling influence on the distribution of glacial deposits. Surficial geology is shown in Figure 3 with unit descriptions in Table 2. A mantle of till about 20 to 50 feet thick covers the-upland. The Advance Outwash occurs beneath the till. Recessional deposits blanket the valley east and north of the upland, where they appear to lie directly on top of the Advance Outwash. At the base of the upland, l~etween elevations of approximately 140 to 200 feet, there is a narrow band where the Advance Outwash is exposed at the surface. The Sparling well site is located just northeast of the upland. A more detailed description of site hydrogeology is presented in section 4.3. 3.5 Surface Water Chimacum Creek is the only significant surface water near the project site. It lies approximately 750 feet east of the Sparling well site. From that point, it flows north-northwest for approximately one mile to a bend where the creek tums to the east and flows out to Puget Sound. The Chimacum Creek watershed, at 37 square miles, is the largest on the Quimper Peninsula. Chimacum Creek is a closed creek, that is, no new water withdrawals are permitted from the creek (Ecology, personal communication, 3/6/96). Chimacum Creek is one of the most productive coho salmon watersheds on the northeast Olympic Peninsula. Chum salmon also mn in the system. The creek is part of the Usual and Accustomed fishing grounds of the Port Gamble S'Klallam Tribe, reserved through the Point No Point Treaty of 1855. While WDF et al. (1993) reported that coho in Chimacum Creek were - healthy, Bahls and Rubin (1996) reported that Chimacum coho were an "at risk population size." Bahls and Rubin measured a variety of parameters at two sites (2&C) located nearly due east of the Sparling well. A:\SUMFINL.TRI 1 0 9/6/96 Rubida (1989) measured flow in Chimacum Creek over a one year period (2/88-2/89). At a site approximately 0.75 miles north (downstream) of the Sparling site, a low flow of 4.81 cfs (cubic feet per second) was measured in August, while a high flow of 14.54 cfs was measured in January of 1989. Upstream flow measurements on Chimacum Creek and a tributary located approximately a mile upstream indicate that the creek is gaining in the reach nearest the Sparling well. Other surface flows near the Sparling well site include two drainage ditches on..the property southwest of the site (Spigarelli). Two wetlands have also been identified on that property. A:\SUMF1NL. TRI 11 9/6/96 125° 124° " SOUND Angeles 123° Vancouver f ~ 33 - MOUNTAINS 18 127' OUNTAINS 12 COLUMBIA IN(~T-ON FRASER LOWLAND '; - UNITED 35 MOUNT · Bellingham · BAKER &8 &14 Skag/ t GLACIER· PEAK PACIFIC OCEAN OLYMPIC PENINSULA · MOUNT RAINIER 121' FIGURE 4 ~HILL MAXIMUM EXTENT OF GLACIER DURING VASHON STADE OF FRASER GLACIATION (after Pessl and others, 1989) TABLE P- DESCRIPTION OF GEOLOGIC UNITS After Pessl et al (1989), Grimstad and Carson (1981), Gayer (1976), and Mullineaux et al (1965). HOLOCENE Hb Beach sand Hs Swamp, marsh and bog deposits PLEISTOCENE Qvt, Vlt Vashon Lodgement Till (Pessl et al) Poorly sorted mixture of rock fragments deposited directly by the Vashon-age ice sheet. Finer components include silt, sand, and clay in variable proportions, constituting a coherent to friable, moderatelg to highly compact matrix in which the coarser components (pebbles, cobbles, and boulders) are firmly embedded. The deposit is typically nonstratified, but subhorizontal layering and fissile structure are locally well developed; may contain lenses and pods of stratified sand, silt, and gravel. Thickness varies considerably but typically ranges from a few meters to as much as 40 m and probably averages between 3 and 15 m. In fresh exposures at depths greater than 1-2 m, the till matrix is light olive gray to gray; clay-rich till tends to have bluish-gray aspect, and weathering of the uppermost few meters typically has produced a matrix color of olive to buff. Qva, Vao Vashon Advance Outwash (Pessl et al) Sand, gravel, silt, and clay deposited by meltwater flowing from advancing ice margin of the Puget lobe of Vashon age; may also include the Esperance Sand, Lawton Clay, and Pilchuck Clay Members of the Vashon Drift. Stratification generally dips southeast to southwest although cross-stratification and cut-and-fill structures are common. Where the entire-thickness of the unit is preserved, flat-lying fine sand, silt, and clay, ranging from nonlayered to thinly laminated, predominate in the lower part. The deposit locally becomes c~)arser upward and consists of moderately to poorly sorted, coarse to medium sand and gravel near the top. Thickness ranges from 1 to more than 60 m, averaging 10-20 m. Good examples of the Vashon advance outwash deposits are preserved on the south and west parts of Camano Island, in seacliff exposures on north and east sides of Marrowstone Island, and in stream banks north and south of Stillaguamish River. This unit will yield moderate to large quantities of water where gravel and sand underlie zone of saturation. The Lawton Clay (Mullineaux et al, 1965) is a dark gray clay interbedded with light gray silt. The upper part is chiefly clayey silt; in part structureless, elsewhere laminated. Grades downward into finer grained beds typical of lower part. Lower part chiefly dark gray clay containing thin light gray silt layers. A few thick beds contain contorted laminations suggesting deposition by subaqueous slumping. Characterized by flattish calcareous concretions apparently formed in thin silt layers. Contains thin beds of sand near base. Vro, Vrd Recessional outwash in meltwater channels and deltas (Pessl et al) Poorly to well-sorted, locally iron-stained sand, gravel, and silt deposited predominantly by meltwater from the receding Vashon-age ice sheet. Thickness commonly ranges from 2 to 10 m, but unusual thicknesses of 20-50 m are found as valley fills along major drainages. These deposits are associated with three principal depositional environments, each containing sediments with somewhat different characteristics: Ice Contact deposits-- Typically deposited in contact with masses of stagnant glacierice; original stratification commonly dips 10° or less with local cut and fill structures; particle size and degree of sorting range widely; locally contains lenses and pods of glacially derived sediment-flow deposits, for example, flow till. Topographic expression commonly is hummocky with closed depressions and irregular ridges caused by collapse of the original sediment surface after melting of buried glacier ice. Collapse structures such as steeply tilted, contorted, and faulted layers are common. Outwash deposits--Deposited downvalley from the zone of stagnant glacier ice. Sediments are horizontally stratified to gently dipping with channel crossbeds and cut-and-fill structures. Deposits are typically composed of medium- to well-sorted, pebble-cobble gravel and coarse to medium sand with local lenses of fine sand and A:\SUMFINL.TRI 14 9/6/96 Qvl Qu Qpfn silt. Topographic expression of outwash deposits, where not modified by erosion, is typically a relatively smooth surface with a gentle downvalley gradient. Alluvial fan deposits--Poorly to moderately well sorted, pebble-cobble gravel with boulders and lenses of finer materials deposited by swift-flowing streams coming from upland areas. Boulders, cobbles, and pebbles are angular to subround and are commonly derived from local sources. Some fans, built into lakes or marine waters, have large-scale deltaic foreset beds. Fan surfaces slope valleyward at angles less than 15°, but individual layers may dip as steeply as 30°. Deposits range in thickness from 20 to 40 m and'interfinger with and overlie the horizontally layered outwash deposits. Unit yields small to large quantities of groundwater where it occurs in sufficient thickness below saturated zone. Vashon lacustrine deposits Undifferentiated Undifferentiated glacial, fluvial, glaciofluvial, lacustrine, and glaciolacustrine deposits: includes sediments resulting from pre-Fraser Glaciations (Possession Drift, Double Bluff Drift), interglaciation (Whidbey Formation), and advance outwash sands of the Fraser Glaciation. The sands and gavels of the pre-Fraser units are of varying permeability and areal extent and generally yield little or no water. Nonglacial Sedimentary Deposits of pre-Fraser Glaciation Age (Pessl et al) Fine-grained deposits of inter-bedded sand, silt, clay, and peat with minor lenses and thin layers of coarse sand and gravel. Layers of silt, clay, and silty sand are light gray to gray and contain layers of dark-brownish-gray to black peat and woody fragments as much as 1 m thick. Stratification ranges from indistinct to thin bedded and locally ishighly deformed. Sand and silty layers are light gray to buff and locally contain highly deformed, finer grained layers. Well-sorted, iron-stained, locally iron-cemented gravel is found as minor channel deposits cut into finer grained sediments that are interpreted as predominantly flood-plain deposits of slow-flowing meandering streams flanked by shallow lakes and swamps. Deposits commonly form resistant near-vertical cliffs; maximum thickness is approximately 80 m. Unit may also variously include nonglacial sediments of the Olympia interglaciation, the Kitsap Formation, and the Whidbey Formation. Cg Thin drift over sandstone TERTIARY Tb Basalt Ti Other igneous rocks Tg Massive sandstone Tc Conglomerate A:\SUMFINL.TRI 15 9/6/96 4.0 Summary of Field Program 4.1 Drilling Program In order to obtain data to achieve the study objectives, three borings were drilled and three monitoring wells were installed. Locations are shown in Figure 5. Split spoon samples were collected during drilling to enable the geologist to log subsurface materials. B6ring logs are shown in Figures 6 through 8. The log of the Sparling well is included in Figure 9 for reference. All three monitoring wells are constructed of 2-inch Schedule 40 PVC. Well construction details are shown in Appendix E. Drilling and installation methods are outlined in the March 1996 Work Plan, attached in Appendix A. A detailed discussion of the site hydrogeology is presented in Section 4.3. Key details regarding monitoring wells are as follows: · Monitoring well MW-1 was drilled approximately 110 feet southeast of the Sparling production well. The boring was advanced to a depth of 225 feet. The well was installed with the screen seated in the Sparling Aquifer at 85 to 100 feet below ground surface (elevation 22 - 37 feet). · Monitoring well MW-2 was drilled and~-nstatled approximately half-way between the Sparling well and Chimacum Creek with the intention of providing data to help assess the effects of increased production on groundwater baseflow to the creek. The boring was advanced to a depth of 45.5 feet. A well was installed in the uppermost water-bearing unit, located above the Spading Aquifer, with screen from 33 to 38 feet (elevation 65 - 70 feet). Monitoring well MW-3 was installed approximately 1000 feet west of the Sparling well to help evaluate the lateral extent and thickness of the units. The boring was advanced to a depth of 131.5 feet. The well was completed in the Sparling Aquifer with the screened interval from 63 to 73 feet (elevation 51 - 61 feet). 4.2 Groundwater Elevation Measurements Groundwater levels were measured in all of the monitoring wells, the Sparling well, and well 3K- 2 (the Spigarelli well) which is located on the adjacent property to the south. The tops of all of the well casings were surveyed to determine elevation relative to sea level. Well casing and ground surface elevations are listed below. Selected water level measurements for June, 1996 are also shown. The groundwater flow direction indicated by these levels is north-northeast. The hydraulic gradient is very flat, about 0.00004. Figure 5 includes an arrow representing the direction of groundwater flow. A:\SUMFINL.TRI 16 9/6/96 5HT Si~REET STREET $~EET FIRST ST~£ET AVEHU£ I > TABLE 3 WELL WELL AND GROUNDWATER ELEVATIONS (Elevations measured relative to mean sea level, NGVD 29) MW-1 MW-2 MW-3 SPARLING 3K-2 MP ELEVATIONt CASING STICKUP GROUND SURFACE 125.43 103.88 124.36 124'137 122.68 2.54 0.83 0 1 0.75 122.89 103.05 124.36 123 121.93 DATE DEPTH TO WATER (ft) GROUNDWATER ELEV 6/14/96 6/14 6/14 45.23 26.00 44.12 80.20 77.88 80.24 6/14 42.42 80.26 DATE 6/18/96 6/18 DEPTH TO WATER (ft) 45.27 26.10 GROUNDWATER ELEV 80.16 77.78 6/18 6/18 6/18 44.20 44.24 42.50 80.16 80.13 80.18 ~: Measurihg point 4.3 Hydrogeology of Project Area This section describes the hydrogeology of the Sparling well vicinity, including geology, groundwater flow rdgimes, and approximate recharge areas. It is based on new information obtained from the field program in addition to well logs and other information previously collected. Figure 10 shows a Hydrogeologic Cross Section of the project area. Geologic Conditions As noted above, the Sparling well is located in an area where recessional deposits blanket the surface. They thin to the west in the site vicinity, until they are no longer present and the Advance Outwash unit is exposed. At the Spading well and MW-l, the surface deposit, a brown sandy silty-gravel identified as recessional deposits, extends to a depth of about 50 feet. At MW- 3, approximately 1000 feet west of the Sparling well, this same unit is only 14 feet thick. Beneath the recessional deposits, a sequence of sands, gravels and silts was encountered, with frequent thin layers of compressed peat and wood. We believe the majority of this unit is the Advance Outwash unit, though it may include deposits from earlier advances in the lower portions. Several layers of water-bearing sands, sandy gravels and gravels were encountered in the middle portion of the Advance Outwash unit. An olive green silt was encountered near the bottom of both MW-1 and MW-3, at depths of 180 and 120 feet, respectively. It extends to the bottom of both wells, at depths of 225 and 131.5 feet, respectively. In MW-l, angular fragments of greenstone were observed near the bottom of the well, indicating proximity to a bedrock source. We believe this unit predates the Fraser Advance. The identification of this unit in both wells is important because it represents the A:\SUMFINL.TRI 18 9/6/96 surface upon which materials of the Fraser Advance were deposited. Significantly, it occurs at very different elevations in MW-1 and MW-3, -57 and 4 feet relative to mean sea level, respectively. This corresponds to a eastward dip of approximately 3.4°. The slope of this underlying green silt indicates that the aquifer materials were deposited into some kind of eastward-dipping trench. One would expect to find a thicker sequence of deposits in the bottom of the trench. In fact, the Advance Outwash and possible underlying materials form a thicker sequence in MW-1 and the Spading well than they do in MW-3. Thicknesses of 130 and 105 feet, respectively, were found. One important point to keep in mind is that isostatic rebound following deglaciation has affected land elevations in this area. That is, the weight of the glacier depressed the earth's crust, which rebounded to its present-day position after the ice melted. According to Thorson (1981), the Tri- Area has rebounded approximately 100 meters (328.1 feet) since the maximum extent of glaciation. The rebound has not necessarily been uniform, however, over relatively short distances, it probably did not vary greatly. Water Beafin§ Units During the drilling program only one significant aquifer was identified; this unit is designated as the Sparling Aquifer in this report. It is so named because it is the primary aquifer for the Spading well. It is a confined aquifer, overlain by at least 30 feet of relatively impermeable material. In MW-l, the unit identified as the Spading Aquifer is characterized as a gray sandy gravel, with occasional stringers of silt. The potentiometric surface (water level) elevation in the Sparling Aquifer is ~pproximate. ly 80 feet, or roughly 20 - 30 feet above the top of the aquifer. The groundwater flow direction measured in the project wells is northeast. The aquifer is thicker and lower in elevation in MW-1 than in MW-3. It is located between elevations 10 to 48 feet above sea level in MW-1 and 51 to 61 feet asl in MW-3. Well 3K-2, the Spigarelli well, also taps the Spading Aquifer. The top of the aquifer in that well occurs at a depth between 48 feet and 64 feet, or elevation 58 to 74 feet. While well driller's logging styles could account for some difference in elevation, it seems that at least the top of the aquifer is higher in elevation in 3K-2 than it is in MW-1. No information is available from that well regarding the bottom of the aquifer. Thin shallow water-bearing lenses were encountered in MW-2 at elevations of about 70 and 78 feet. The lower one is about 20 feet higher than the Spading Aquifer and separated from it by at least five feet of silt and clay. Chimacum Creek lies at an approximate elevation of 70 - 75 feet asl, roughly the same elevation as these shallow lenses, and is located about 440 feet east of MW-2. Thus, we believe that the water-bearing lenses in MW-2 are shallow units in hydraulic continuity with the creek. Results of the aquifer test (Section 5) support these conclusions. We suspect the groundwater flow direction in these lenses is east-northeast. A:\SUMFINL. TRI 19 9/6/96 In the Sparling well, another water-bearing unit exists beneath the Sparling Aquifer. It is located at a depth of approximately 160 to 170 feet (37 to 47 feet below sea level). This unit is separated from the Sparling Aquifer by about 35 feet of clay and is tentatively identified as the Lower Water-Bearing Unit. This unit was not encountered in MW-1. Apparently, the Lower Water- Bearing Unit pinches out between the Spading well and MW-1. Its extent in other directions is not known. Neither the head nor the groundwater flow direction for this aquifer are known. Extent of Spading Aquifer - The shape and thickness of the Sparling Aquifer is not obvious from the drilling data. However, from the cumulation of information, we infer that is an elongate buried-channel type aquifer, long in the north-south direction. We know from the geol'ogic history of the area that the aquifer was deposited as part of an outwash plain in front of the advancing glacier. According to Grimstad and Carson (1981), the unit we identify as the Sparling Aquifer was "laid down by a fast-flowing glacial stream which winn6wed out the fines, leaving a porous and permeable unit capable of storing and transporting large quantities of water." We know that this river was flowing south and was contained to the west by the Anderson Lake upland. The aquifer is probably snake-like in shape, thinner at the edges than in the middle. It is bounded on the top and bottom, as well as the edges, by som~ mixture of silt, fine sand, and clay. It may or may not be hydraulically connected to other water bearing units within the larger Advance Outwash unit. It is apparent -from our stUdy that the basal unit beneath the former river (now the Sparling Aquifer) -- the green silt -- was either a valley or an eastward dipping slope. Aerial photos for the_ vicinity (Figure t 1) show recent drainage patterns. Major features left when recessional deposits were laid down can also be discerned. Just as recent patterns follow recessional patterns, so those patterns prObably also reflect drainage from the Advance Outwash. A general trend is evident along a line from approximately the Sparling well to the bedrock outcrop on the Anderson Lake upland. It is probable that this reflects an ancestral drainage, and that the Spading Aquifer roughly parallels it. Another drainage trend is evident running from the Sparling well due west to the pond on the north end of the upland. Because of its orientation, however, it appears to b'e more recent in nature. The extent of the aquifer to the northeast is pure speculation. It may follow the continuation of the former drainage toward Chimacum Creek which is visible on the aerial photos. Well logs from the other side of the creek do not show anything definitive regarding the extent of the aquifer.' 4.4 Water Quality Testing Groundwater samples were collected from each of the monitoring wells for analysis of iron, manganese, and total organic carbon (TOC). Both total and dissolved levels were measured for the metals. Results are shown in Table 4. The analytical results indicate levels of these constituents in all of the monitoring wells which are comparable to or higher than those in the Sparling well. The high values for MW-3 likely result from the presence of particulates in the sample. Levels in the Sparling well are typically 6 mg/L (milligrams per liter) for iron and 0.5 mg/L for manganese. The secondary MCLs (maximum contaminant levels) for these A:\SUMFINL.TRI 20 9/6/96 Figure 6. Log of MW-1 Subsurface Materials BROWN SILTY, CLAYEY SAND AND GRAVEL (GM-GC), Topsoil, very dense, sand medium to coarse, organic material, gravel to cobbie size. BROWN SILTY SANDY GRAVEL WITH COBBLES (GM), very dense, dry, sa~d medium to coarse, gravel and cobbles angular to rounded, a variety of lithologies - green, gray, and tan volcanics, metamorphics and sedimentary. TAN SILTY GRAVEL WITH COBBLES (GM), medium dense, dry to moist, occasional sand, fewer Frees below 6.5 ff., gravel coarse, lots of weathered volanics. Softer from 10 - 15 ft. Fewer Frees at 17 ff. - sand is course and angular, cobbies larger at 17 ft. Clay at 24 - 25 ft., then fairly clean gravels and cobbles. Rusty staining on cobbles at 30 ft. TAN SILTY GRAVEL WITH COBBLES (GM), Medium dense dry, some sand, trace of clay. Sandier at about 37 ft. BROWN CLAYEY ORGANIC SILT (ML-OL), Medium stiff, moist, soft, sand medium to coarse, some small wood pieces. GRAY SANDY SILTY CLAY (CL), stiff. GRAY SILTY SAND AND GRAVEL (GM), Medium dense to bose, moist, sand i'me to coarse, gravel to 4cm. or greater, trkce of clay. GRAY CLAYEY SILT LENS (ML), peat chunks, dense, dry to moist. GRAY SILTY SAND & GRAVEL (GM), Medium dense to loose, sand coarse, gravel to lcm. Trace of clay. Occasional chunks of red-brown silt. Water bearing below about 63 - 64 ft. GRAY SAND (SW-SP), fmc to course, medium dense, wet, occasional gravel, sand angular, heaving, peat chuaks at 65 ft., sand coarsens downward. BROWN SILT (OL) with peat and wood chunks. GRAY GRAVELLY SAND (SW-SP) wet, loose, sand I-me to coarse, gravel to 3 cm. or larger, trace of silt. BLUE GRAY SANDY GRAVELLY SILT (ML) GRAY SANDY GRAVEL (GP) with trace of silt, sand mostly medium to coarse, some cobbles, occasional lenses of very fine to fme sand, lenses of well-sorted angular gravel, highly variable. GRAY SILTY GRAVEL (GM) with clay and cobbles, gravels to cobbie size, very dense, tight. GRAY SANDY GRAVEL (GP), tight, gravel to cobble size, trace of silt, sand occurs in lenses of f'me sand and as medium to course sand within gravel, cobbies to 3" or more, gravel clean and mostly 1 - 2" diameter from 85-90 ft. Depth (ft.) 10 20 30 40 50 60 70 8O 9O Elevation (ft. above msl) 123 113 103 93 83 73 63 53 43 33 CH2M HILL Tri-Area Groundwater Study Figure 6. Log of MW-1 (continued) Subsurface Materials GRAY SILTY SANDY GRAVEL (GM), very dense, moist, gravel Imm to 2 cm., occasional cobbles, some clay, more sand (frae to coarse) at 100 ft., clay occurs as inclusions. Heaving at 100 ft. and below. This unit is gray sandy gravel with stringers of dense clayey silt. Clay stringer at 108 ft. GRAY-BLUE SILT (ML) with clay and lenses of very frae to f'me sand, dense, dry. GRAY SILTY SANDY GRAVEL (GM) with clay. GRAY SAND (SP-SM), medium dense, moist, sand time to medium. GRAY SILT (ML) with peat inclusions and brown silt, dense, dry to moist. GRAY SAND (SP), medium dense, moist GRAY SILT (ML) GRAY CLAY (CL) GRAY SILT (ML) with clay. Traces of brown silt, microtrace of peat at 140 ft. GRAY SILTY SAND (SM), medium dense, moist, sand very frae to medium. GRAY SILT (ML) trace of peat, occasional clay pods. GRAY CLAYEY SILT (ML), very dense, dry, lenses of bluish clay. Becoming green-blue downward, microtraces of white flecks. Depth (ft.) 120 130 140 150 16o 180 Elevation (ft. above msl) 33 23 13 -7 -17 -27 -37 -47 -57 CH2M HILL Tri-Area Groundwater Study Figure 6. Log of MW-1 (continued) Subsurface Materials GRAY SAND (SW), sand very fmc to medium, trace of silt, occasional clay. GRAY-GREEN CLAYEY SILT (ML), very dense, dry to moist, trace of clay, some organics. GRAY SILTY GRAVELLY SAND (SM) GRAY-GREEN SILT (ML) GRAY SILTY SAND (SM) GRAY-GREEN SILT (ML) with sand and gravel, trace of white flecks (calcareous concretions) At 195 ft., layers of peat up to 1/2 inch thick, small chips of angular green rock. INTERBEDDED GREEN SILT, GRAY SAND AND GRAVEL, AND BROWN CLAYEY SILT (GM & SM), laminations visible in silt, gravel to 4 cm., subrounded, various lithologies, some peat and organics, some calcareous concretions. Fine to coarse sand with occasional gravel (greenstone) at 205 ft. GRAY SANDY SILTY GRAVEL (GM) INTERBEDDED GRAY SANDY SILTY GRAVEL AND SILT (ML & GM) GREEN SILT (ML) with peat, trace of tiny rock chips. tNTERBEDDED GREEN-GRAY SANDY SILT AND SILTY SAND (ML & SM) Bottom of hole at 225.5 ft. Depth (ft.) 180 190 200 210 220 Elevation (ft. above msl) -57 -67 -87 -97 230 -107 CH2M HILL Tri-Area Groundwater Study Figure 7. Log of MW-2 Subsurface Materials BROWN ORGANIC SILT w/SAND, topsoil. TAN SILTY SANDY GRAVEL (GM), loose to medium dense, dry, some clay, organics (roots). TAN SANDY SILTY GRAVEL WITH COBBLES (GP), medium dense, moist, sand f'me to coarse, gravel to cobble size. More silt and some clay at 19 ft. RED-BROWN SANDY GRAVEL (GP), loose, moist, some silt, red iron deposits in clean gravel. BROWN SILTY GRAVELLY SAND (GM), loose, moist, sand £me to coarse, less gravel downward. Cuttings extremely rusty red colored. BROWN SILTY SAND (SM), medium dense, moist, some gravel, sand mostly medium, silt in inclusions, peat and red-brown silt chunks at 31.5 ft. Water bearing at 34 ft. GRAY SAND w/silt (SM), silt is in thin brown interbeds. BROWN ORGANIC SILT AND PEAT (OL), medium dense, dry to moist, - some wood pieces. GRAY SAND (SW), silt occurs as brown chunks. BROWN PEAT WITH ORGANIC SILT AND WOOD (Pt), dense, dry, wood to log size. Bottom of hole is a log. Bottom of hole at 45.5Tt. Depth (ft.) 10 20 30 40 50 Elevation (ft. above msl) 103 93 83 73 63 53 CH2M HILL Tri-Area Groundwater Study Figure 8. Log of MW-3 Subsurface Materials BROWN SILTY SAND (sM), topsoil. BROWN SILTY SANDY GRAVEL (GM); medium dense, dry to wet, sand frae to coarse Water bearing from 6 to 14 ft. GRAY SANDY CLAYEY SILT (ML), medium dense, moist, sand very f'me to £me, occasional gravel at top, clay interbedded as layers up to 2 in. thick. Clay and silt in varves, approximately 1.5 cm. each. Trace of peat and wood at 30 ft. GRAY-BLUE SANDY GRAVEL WITH COBBLES (GM), very dense, moist, gavel angular to rounded, sand very f'me to coarse, some clay, variety of lithologies, gravel to cobble size. Looks like till or ice - contact deposits. GRAY SANDY GRAVEL (GP), loose to medium dense, wet, water bearing. GRAY SANDY SILTY GRAVEL (GM), very dense, moist, same unit as above but with silt, some cobbies. GRAY SAND (SW), medium dense, moist, sand frae to medium. GRAY SILTY SAND (SM), sand very Fme to frae, heaving. GRAY SILT (ML), medium dense, moist. GRAY SANDY GRAVEL (GP), dense, moist to wet, some silt, gravel to cobbie size, sand fme to coarse. GRAY SILT OML), medium dense, dry to moist, trace of clay. Trace of tiny peat inclusions at 81 ft., occasional black flecks ~ look like weatherize minerals, sub-horizontal partings about 1 cm. apart. GRAY SANDY SILT 0VlL), medium dense, dry, sand very frae, trace of peat. Depth (ft.) 0 10 20 3O 40 50 60 · 70 80 90 EIevatlon (ft. above msl) 124 114 104 94 84 74 64 54 44 34 CH2M HILL Tri-Area Groundwater Study Figure 8. Log of MW-3 (continued) Subsurface Materials GRAY GRAVELLY SILTY SAND (GM), medium dense, moist, unit is layered sand, gravel and silt. GRAY GRAVELLY SILTY CLAY (CL), dense, moist, gravel to 3mm. BROWN SILT WITH PEAT (ML-OL), very dense, dry flecks of peat. GRAY SANDY SILT (ML), peat layers and inclusions, sand very f'me and layered with silt. Greenish clay lens at 106 ft. BROWN SILT WITH PEAT at 108 to 109 ft. contains many wood chips GRAY GRAVELLY SAND (SW), medium dense, wet, water-bearing at 110 ft., sand f'me to coarse, gravel to 2 cm. Water level rises to 64 ft. BROWN ORGANIC SILT WITH PEAT (OL), very dense, dry, sub- horizontal partings. GRAY SANDY GRAVEL (GW), medium dense, wet, gravel to 2 cm. GRAY BROWN SILT WITH PEAT (ML-Pt), much plant material, sub- horizontal partings, trace of gravel. GRAY-GREEN SILT (ML), very dense, dry to moist, trace of gravel to 3mm, trace of peat. GRAY-GREEN SILTY GRAVELLY SAND (SM), medium dense, moist, large (to 2 in.) wood chunks, sand very f'me to frae. BROWN ORGANIC SILT AND PEAT (OL-Pt), very dense, dry, many wood chips. Bottom of hole at 131.5 ft. Depth (ft.) 90 100 110 120 130 Elevation (ft. above msl) 34 24 14 -6 140 -16 CH2M HILL Tri-Area Groundwater Study FIGURE 9 BORING LOG OF SPARLING WELL Topsoil Hardpan with coarse gravel Hardpan with gravel and boulders Hardpan with finer gravel, softer Fine sand with some water Heaving sand Coarse sand, water Peat Heaving sand Clay Coarse gravel Heaving sand DEPTH (feet) 0 N-.-o -(~-: '-: '~--. -'t~ 2..,.. , · , '_....~2.-7 ~7=' ?., ~'--~ .m,'; ,---j' "--". ~.-...2_-. ~','~'. -' ..---_2 10 ~ ...... :5-:~"-- .... 20 __ 2-'. ~_ _l-'.--..~" '7 '. ,';:' _'.~.-7'- :2..~, 20,--. 30 .~,_.~:...-_,?..:. 2"7, h.-'q", · ,'--v --',~-"_' 40 ~,&'-7. O"-:-a'2~'-'.: ,7,.L%x-.-r"- ,-;. 50 ,7.&",~-~ · '.., _.. ~ .... .' .'. ,~' ,: r ~' 60 '?_.: : :7. ;.'..~ :'.:,.."...;?.=_ 80 -" .........."= .:: .:.:..'. ~--?,: :'.:.; ,' ~..,.b...',~,4.. 90 ., :..'.-'. ,.- APPROX. ELEVATION (ft above msl) NOTES 125 105 85 _ Water level 65 45 (FIGURE 9 DEPTH (feet) continued) Medium gravel with mixed sand Pea gravel, water-bearing 100 Medium sand and gravel with some clay, hard Clay and gravel with water Coarse sand and gravel APPROX. ELEVATION (it above msl) 110 120 Blue clay 130 140. Coarse sand Blue clay 150. Coarse sand and pea gravel -- 160. Clay and sand Gravel and coarse sand Clay 170. 180. Bottom o.fboring at 184 feet -~-I 9' .-!: .'- =].': ," ? t' =16. ,, ,,' j 5' ,E 25 1 ,' "~ ".'/L~_.'_" - . ..~'- °:' °-- 5 / 7, ::.: I.' ;2; i.'-. ; .' ",'. ,':t : ': ,~ /" '"t "- b'.~?'":'~ ' '6 :~. i. / ~""--'~0' '"~ / ~. -. .}, ,;- '~'..:',,_- .'t.. :' .'.. · · -: '." O"* ."~'~- · .~..· :. ~.. ~. ~.'. '.~,..~ .} ~_ :' ." ~, "~'-'.',--2 o.. v" :: .': "', ';:: ,.J ;/ ', '..,. '. · ;..~....~_~ '.. -. :; ~. ~..';- ,...'-, '... a -55 NOTES Screened intervals Lower Water- Bearing Unit 0 -% 31W-3 SPARLING \VELL blW-1 RIIODY I)RIVE (HIGII\VAY FIGURE 11 AERIAL PHOTO OF PROJECT AREA 1972 TRI-AREA GROUNDWATER STUDY ~/-//// constituents are 0.3 mg/L and 0.05 mg/L, respectively. The groundwater currently produced from the Sparling well is treated at an on-site plant to reduce constituent levels prior to distribution. Total coliform samples were also collected, however, the results do not appear reliable. Sample collection methods were described in the Work Plan. Copies of Laboratory Reports are included in Appendix F. TABLE 4 - ANALY"I]CAL TEST RESULTS ANALYTE (rog/L) MW- 1 MW-2 MW-3 Total Iron (Fe) Dissolved Iron Total Manganese (Mn) Dissolved Mn Total Organic Carbon (TOC) 6.7 15 150 NDt 0.63 9.5 0.66 0.49 3.0 0.67 0.39 0.3 3.5 17 94 Total Coliform (#/100mL) 9 1.7 500 l: Not detectable at a detection limit of 0.10 mg/L 5.0 Aquifer Test 5.1 Methods An aquifer test was conducted utilizing the Sparling well as the pumping well. Water levels were measured in all three monitoring wells, the pumping well, and well 3K-2 (Spigarelli) for the duration of the test. The well was pumped for 24 hours at a rate of approximately 612 gpm (gallons per minute). Actual discharge was measured periodically using the flow meter installed on the well. Pumped water was treated and piped' into the storage and distribution system. After 24 hours, the pump was shut off and water levels were measured during a 24 hour recovery period. Water levels were measured in the pumping well and in MW-1 using Geokon vibrating wire pressure transducers. A third transducer was left exposed to the atmosphere to correct for barometric fluctuations during the test. Measurements were taken every minute or less for most of the test; near the end, the collection interval was changed to 10 minutes. A Geokon Model 8005 three channel electronic datalogger connected to a laptop computer was used to control data collection and storage. Water levels in the remaining wells were measured manually using Solinst electronic water level tapes which had been checked against each other. Manual water A:\SUMFINL.TRI 31 9/~/96 levels were measured according to the schedule in Table 5. Periodic manual water level measurements were also taken in MW-1 and the pumping well as a field check on the transducers. An example data sheet is shown in Appendix G. Prior to beginning the aquifer test, the watches of all personnel collecting data were synchronized. In addition, procedures were reviewed in a pre-test meeting to ensure that all participants followed consistent methods. TABLE 5 WATER LEVEL MEASUREMENT INTERVAL (AFTER DRI$COLL, I 986', P353) Time since pumping started or stopped in minutes Time interval between measurement in minutes 0-60 2 60-120 5 120-240 10 240-360 30 360-termination 60 5.2 Special Considerations Pump Shut-Down Effects Because the water treatment system needed to be backflushed periodically during the course of the test, the pump was shut off for approximately 15 minutes at a time on several occasions. During these times, approximately 13,000 gallons of water was discharged to the pond behind the pumphouse. The exact times the pump was off and the amount of water discharged was recorded during the test. Both the Sparling well and MW-i, the closest monitoring well, returned to their pre-shutoff water levels immediately upon resumption of pumping. The spikes at these times appear on the plots. No obvious recharge effects were noted in either of these wells due to discharge of water to the pond. However, at the end of the aquifer test, the water level in MW-2, which was screened in a shallow water-bearing lens, began to increase slightly, possibly showing recharge from the pond. Neither MW-3 nor well 3K-2, both approximately 1000 feet from the pumping well, showed any observable change attributable to pump shut-down. Effect of Sparling Well Being Screened in Multiple Water Bearing Units Another special consideration for this particular aquifer test is the fact that the existing pumping well is screened over several different water bearing units. The units from depths of approximately 75 to 124 feet are likely all part of the Sparling Aquifer. The screened interval at a depth of 158 to 169 feet withdraws groundwater from the Lower Water Bearing Unit. In addition, a liner has been installed in the Sparling well which likely affects the flow inside the well. The effects of these factors are discussed below. A:\SUMFINL. TRI 32 9/6/96 Evaluation of Well Efficiency Well efficiency for the pumping well was calculated using the method outlined in Driscoll (1986, after Mogg, 1968). This method uses a plot of distance versus drawdown, extrapolating to the distance of the well radius. The ratio of theoretical to actual drawdown is an estimate of well efficiency. The efficiency of the Sparling well was calculated to be approximately 40%. 5.3 Analysis Methods The data were analyzed using the CoOper-Jacob modification to the Theis non-~quilibrium equation, utilizing the following graphical and analytical procedures: · time-drawdown plots for the pumping portion of the test; · residual drawdown versus time plots for the recovery portion of the test; and, · calculated recovery versus time plot for MW-1. In addition to the quantitative aquifer parameter data obtained through these analyses, the graphs were scrutinized to ascertain qualitative information about the aquifer. The results of the aquifer test are described below. The equations are presented in Appendix H. Appendix I contains the data plots for the test. 5.4 Aquifer Test Results Spading Well- The Pumping Well When pumping began, the water level in the Sparling well dropped within one minute to approximately 15.4 feet below static water level (SWL), where it stayed for the duration of the test. It fluctuated slightly due to pumping irregularities, buT-was generally steady for the 24-hour period. During pump shut-downs, the water level rebounded to about 0.2 feet below SWL, but dropped immediately to its previous level once pumping resumed. The steady water level is probably indicative of the-aquifer's high transmissiv~ity. Leakage other water-bearing units, specifically, the Lower Water-Bearing Unit, may also have contributed to the steady water level in the Spading well. The recovery data for the Sparling well were plotted (shown in Appendix H) and used to calculate the transmissivity value range shown in Table 6. A:\SUMFINL.TRI 33 9/6/96 TABLE 6 CALCULATED SPARLING AQUIFER PARAMETERS Well and Phase EARLY2 DATA MW-1 pumping MW-3 pumping 3K-23 pumping Average early Transmissivity (T)~ Range (gpd/ft) 1.35 x 106 1.12 x 106 1.38 x 106 1.28 x 106 (0.184 m2/s) Storativit? (S) (unitless) 2.32 x 10-5 LATE4 DATA EFFECTIVE T MW-1 pumping 8.50 x l0s MW-3 pumping 9.85 x l0s 3K-2 pumping 6.73 x l0s Average late 8.36 x l0s (0.120 m2/s) Sparling recovs 1.15 - 1.62 x 106 --- MW-1 recov 1.20 - 1.28 x 106 2.2 x 10-4 MW-3 recov 1.74 - 2.15 x 106 --- 3K-2 recov 2.02 - 2.69 x 106 --- Average recov 1.73 X 106 (0.249 m2/s) - Average S 1.22 x 10-4 These are the transmissivity and storativity values calculated from the. aquifer test. However, since a portion of the water pumped was obtained from the Lower Water Bearing Unit, the actual aquifer properties are lower. The Lower Unit comprises approximately 25% of the total screened area in the well. Thus, in the conclusions below, the T and S values have been reduced by 25% to present a conservative estimate of aquifer parameters. Early data are representative of the actual formation materials. Spigarelli well, 3K-2 Late data define more of an "effective" transmissivity, representing a greater portion of the aquifer. Recovery phase Wells MW-l, MW-3 and 3K-2 The data from these wells were plotted on time-drawdown graphs and residual drawdown recovery graphs, shown in Appendix H. In addition, data from MW- 1 were plotted and analyzed using calculated drawdown during the recovery phase. The transmissivity and storativity values calculated using these plots are shown in Table 6. A:\SUMFINL.TRI 34 9/6/96 Inspection of the plots for these wells all show an initial steady response to pumping. Part way into the test, the slope of each plot becomes steeper, indicating greater drawdown for the same pumping rate. A likely explanation for this increased drawdown is that an impermeable boundary was encountered by the expanding cone of depression from the Sparling well. The boundary encountered was undoubtedly the margin of the aquifer in a horizontal plane. The slope break occurred at about 150 minutes in MW-1. At that time, the cone of depression would have expanded radially slightly farther than both MW-3 and 3K-2, which are both' approximately 1100 feet from the Spading well. Drawdown was first observed in MW-3 and }K-2 at approximately 60 - 90 minutes after pumping began. Observation of the recovery plots of residual drawdown versus fit' (the ratio of time since pumping started to the time since pumping stopped) shows that, for all three of these wells, the line is displaced slightly to the left or downward of the line for an ideal well. An ideal well would intercept the upper left comer, with zero residual drawdown when t/t' is 1. This indicates that not all theoretical assumptions of the method were met. The plots imply that the wells had not fully recovered 24 hours after pumping stopped. Possible explanations are that the aquifer is not being recharged by a constant head source sUch as a river or creek and that a boundary such as the edge of the aquifer was encountered. Well MW-2 - Monitoring well MW-2 is located approximately 360 feet east-northeast of the Sparling well. This well was monitored throughout the pumping phase of the aquifer test. It did not show any change in head until the final hours of the test, when the water level actually increased by a few hundredths of a food This well is screened in a thin water-bearing unit above the water-bearing units tapped by the Sparling well. It is completed in the unit which appears to be in hydraulic continuity with Chimacum Creek, based on elevations. The increase in head in MW-2 might be due to recharge of this unit by the water from the infiltration pond behind the Sparling well. If this were the case, water discharged into the infiltration pond might eventually drain into Chimacum Creek. The change was small enough -- 0.02 feet -- that it could represent a normal fluctuation. Since no drawdown was noted during the pumping phase, water levels were collected only during the initial hour of the recovery phase. Projected Well Yield Projected well yield was estimated by extending the distance-drawdown graph for MW-1 and constructing time-drawdown relationships for the pumping well. Using these methods, it is estimated a new production well could produce at least 1000 gpm, probably more, if there were adequate recharge. Furthermore, for a well 100 feet from the production well, we estimate that less than two feet of drawdown would be caused by continuous pumping at 1000 gpm for a period of two months. In other words, two production wells could be located fairly close together with minimal interference. A key assumption in this analysis is that no other significant impermeable boundaries would be encountered by the cone of depression. A:\SUMFINL. TRI 35 9/6/96 5.5 Aquifer Test Conclusions In summary, the following conclusions were reached from the aquifer test: · There does not appear to be a constant head source (recharge boundary) such as a river recharging the aquifer; · The Sparling well is not in hydraulic continuity with Chimacum Creek; · The steady head observed in the Sparling well was caused by the aquifer's exceptionally high transmissivity, as well as possible leakage from other water bearing units; · The estimated transmissivity of the aquifer is approximately 1 x 106 gallons/day/foot (0.140 - 0.194 m2/second). The "effective" transmissivity of the aquifer, drawn from late-time data, is 8 x l0s gpd/ft (0.120 m2/s). These are excellent T values for a water-production aquifer. The estimated storativity of the aquifer is approximately 9 x 10-s (0.00009). These values are the calculated values reduced by 25% to present a conservative estimate of aquifer parameters; · The efficiency of the Spading well is estimated to be about 40%; · Water from the overflow pond behind the Spading pumphouse may eventually drain into Chimacum Creek. 6.0 Water Balance Estimates of Aquifer RecharDe The water balance or hydrologic budget method was used to estimate the volume of water recharging the groundwater. This method looks at the total water inputs and outputs from a basin. Under normal circumstances, all the water in a basin comes from precipitation. Some of it runs off as rivers and streams, some evaporates and is used by plants, and the rest normally infiltrates into the earth to become groundwater. Pumping or other water withdrawals may also need to be accounted for. The water balance equation over an annual period is as follows: P = Re + Ro + Et + dS where, p = precipitation (inches/year) Re = recharge to groundwater (in/yr) Ro = runoff to surface water (in/yr) Et = evapotranspiration (in/yr) dS = change in storage (in/yr) The calculations for this study were prepared for an annual water cycle. Hence, seasonal variations were not considered. This is a common approach for groundwater since aquifers tend to attenuate seasonal influence. A :\SUMFINL.TRI 36 9/6/96 Another key factor is the basin area used in calculations. For this study, two estimates are presented. The first considers the entire 37 square mile Chimacum Creek basin. The second estimate considers a smaller area which more closely approximates the actual recharge area of the Sparling Aquifer. 6.1 Basin-Wide Analysis The basin-wide analysis considers the entire Chimacum Creek watershed, noting that all of the water from this basin eventually drains out through Chimacum Valley, either as surface water or groundwater. The following values were used for this calculation: Parameter Value Source P = 24 in/year Ro = 3.7 in/yr Et -- 9 in/yr dS = 0 in/yr [US Weather Bureau (USWB, 1968)] [Obtained by totaling the annual flow in Chimacum Creek near the Sparling site, (Bahls & Rubin, 1996)] [Measured Et in Cedar River Basin, (Simpson, 1983), adjusted slightly for local conditions] [Assumed negligible] The potential groundwater recharge value obtained from these values is approximately 11.3 inches per year. This would equate to 19.8 MGD (million gallons per day), or 13,774 gpm (gallons per minute) over the 37 square mile basin. This number is less than the 26.2 - 28.8 MGD value for recharge obtained for this area in the Jefferson County Study (EES & PGG, 1994). However, we believe it is still far greater than the actual recharge to any particular water- bearing unit. The nature of the Advance Outwash unit, which is the primary aquifer on the Quimper Peninsula, is that it contains numerous smaller water-bearing units with limited if any connection to one another. _. 6.2 Spading Vicinity Recharge Analysis To more accurately estimate the amount of recharge to the Sparling Aquifer, the actual recharge area was estimated. To help visualize the type of recharge occurring, the vicinity was divided into recharge zones. The zones were identified based on geologic information, groundwater flow information, aerial photos, and topographic maps. Since the exact extent of the aquifer is not known, these zones are approximate only. Figure 12 shows the areas used to approximate these zones, which are described below. A more accurate estimate of recharge zones should be prepared to delineate wellhead protection areas. The total area included in the recharge estimate extends south to Old Anderson Lake Road, east to Chimacum Creek, north about 3/4 of the way to the section line, and west to the height of land. The total area of these zones which most directly recharge the Sparling well is 2.5 square miles. Direct Aquifer Recharge Zone: This is the area where the Advance Outwash unit is exposed at the land surface. This zone forms a band at the base of the Anderson Lake Upland. In this zone it is assumed that precipitation and runoff enters directly into the Advance Outwash A:\SUMFINL.TRI 37 9/6/96 unit. It is likely that only a portion of it enters the Spading Aquifer, the rest infiltrating other thin units, or flowing downhill as runoff. Ditching at the base of the hill in the 1940s and 1950s may have actually enhanced infiltration into the Advance Outwash, as well as shallower perched units. Runoff Zone: This zone is the sloping upland west of the site. This is the largest recharge zone. Precipitation landing on this zone would infiltrate or run-off in a dox~nhill direction. Low permeability till is the surficial unit in the entire runoff zone, thus a higher than average percentage of the precipitation is assumed to mn-off. Since the Advance Oul~wash is exposed at the base of the hill, much of the runoff which reaches that zone could directly infiltrate the aquifer. Recessional Zone: This is the zone on the valley floor where the Advance Outwash is overlain by Recessional Deposits. Precipitation landing here would primarily drain into both the Spading Aquifer and perched water bearing units. Bedrock Infiltration Zone: This is the zone where bedrock is exposed at the surface, primarily the cliffs east and northeast of Anderson Lake, including Tamanous Rock. In this zone, precipitation would be split two ways. Some would mn-off to the forest below the outcrops. The rest would enter the ground directly by flowing along fractures and bedrock surfaces. This water could potentially recharge the aquifer directly. TABLE 7 SURFACE AREA OF RECHARGE ZONES - SMALL BASIN ANALYSIS Recharge Zone .......................... Surface area- ......................... (square feet) (acres) (sq. miles) Direct Aquifer Zone 2.61 X 106 59.9 0.009 Runoff Zone 40.34 X 106 926.2 1.45 Recessional Zone 22.37 X 106 513.6 0.80 Bedrock Zone 3.28 x 106 75.3 0.12 Total 68.6 x 106 1575 2.46 The equation used to estimate recharge is the same as above; rearranged to solve for recharge, it is: Re = P - Ro - Et - dS A:\SUMFINL.TRI 38 9/6/96 I :/ / '4 nder~o~ © 0 II. /oo~ ........ ~\\'~ o\\ .... \ \ The parameter values used in the calculations are as follows: Parameter Value Source P = 24 in/year Ro = 3.4 in/yr Et - 9 in/yr dS = 0 in/yr [US Weather Bureau (USWB, 1968)] [Obtained by calculating the gain in flow in Chimacum Creek (Bahls & Rubin, 1996) between ends of the delineated area. Fig'tire used is 75% of gain, assuming that 25% enters from east bank.] ~ [Measured Et in Cedar River Basin, (Simpson, 1983), adjusted slightly for local conditions] [Assumed negligible] The recharge estimate derived from this smaller basin analysis is 1.36 x 106 gallons per day, (1.36 MGD) or 944 gpm. This is a conservative estimate, based on a small recharge basin. Furthermore, it doesn't consider recharge through groundwater flow. We believe it is more realistic in relation to the Spading Aquifer than the large basin analysis of recharge. 7.0. Summary and Conclusions 7.1 Summary of Hydrogeology - The following summarizes the information obtained from the hydrogeologic study, the aquifer test, and the basin analysis. In the proj_ect vicinity, one primary aquifer was identified, which we have designated the Sparling Aquifer. The properties of the Sparling Aquifer are as follows: · It is a confined aquifer located within the Advance Outwash unit. · Groundwater flow is to the northeast. · The aquifer transmissivity was calculated to be approximately 1 x 106 gallons/day/foot (0.140 - 0.194 m2/second). The effective transmissivity, more accurate for long-term predictions, is 8 x l0s gpd/ft (0.120 m2/s) These are excellent T value for a water-production aquifer. The estimated storativity of the aquifer is approximately 9 x 10's (0.00009). · The Sparling Aquifer receives at least 940 gallons per minute of recharge on an annual basis, which is enough to support the existing water right. · The aquifer recharge area is west and south of the Sparling well, encompassing at least a portion of the Anderson Lake upland. A:\SUMFINL.TRI 40 9/6/96 7.2 Summary of Predicted Well Yield Study results suggest that groundwater production from the new well will be limited by the availability of recharge rather than the aquifer's ability to transmit water. Based on the aquifer test, it is estimated that a new production well could produce at least 1000 gpm. The conservative basin analysis indicates that the Sparling Aquifer receives 940 gpm of recharge annually. This figure represents the volume of water which could be produced,.without overpumping the aquifer. The best location for a new production well, based on the goal of maximizing production, is as close to the Sparling well as possible. If two wells are to be pumped simultaneously a distance of about 300 feet should be maintained to reduce interferance. We estimate that interference would be minimal, assuming no other major impermeable boundaries are encountered which weren't apparent during the aquifer test. 7.3 Risk of Seawater Intrusion Based on geologic conditions which show a thick sequence of silt and clay beneath the Sparling Aquifer, as well as the existence of a bedrock bowl which may isolate the Tri-Area from seawater influence, it appears that the risk of seawater intrusion to the Sparling Aquifer is negligible. Furthermore, the static water level in the Sparling Aquifer is about 80 feet above sea level, creatirig a substantial seaward gradient which would need to be reversed before seawater intrusion could take place. 7.4 Potential Impact on Chimacum Creek Observations of water elevations, geology, and the response in MW-2 to pumping in the Sparling well indicates that the Sparling Aquifer is not in direct hydraulic continuity with Chimacum Creek. Rather, it appears that shallow perched groundwater zones flowing through the recessional deposits are in connection with the creek. These perched zones, which are tapped by monitoring well MW-2, did not evidence drawdown in response to pumping the Sparling well during the aquifer test. Other wells located three times farther away from the pumping well did show drawdown. In addition, the Sparling Aquifer lies beneath Chimacum Creek and appears to be separated from it by at least 5 feet of silt. Thus we infer that Chimacum Creek is not in direct hydraulic continuity with the Spading Aquifer. 8.0 Recommendations 8.1 19ew Production Well Location We recommend installing a new production well in the Spading. Aquifer. We anticipate that a new 16 inch well could produce a minimum of 1000 gpm, which would be enough to produce the A:\SUMFINL. TRI 41 9~96 appropriated groundwater right on an annual basis. It would also reach the capacity of the treatment plant. However, it might not be sufficient to meet peak need, or the peak day water right of 2250 gpm. At these times, pumping capacity could be stepped up and/or supplemented by pumping the Sparling well. The well should be located as close to the Sparling well as possible to increase the likelihood of it being a high capacity well. It must be at least 100 feet from both the septic fi'eld and-the infiltration pond at the site. If the new well and the Sparling well are to be pu~ped simultaneously, a distance of 200-300 feet should be maintained between them tO reduce interference. 8.2 New Production Well Specifications As mentioned above, we anticipate that the new well will be able to produce at least 1000 gpm. If the well were operated 60% of the time (continuously for approximately 6 to 7 months per year), this would satisfy the water right for average annual flow. The water balance for the area indicates that there is sufficient recharge to support this level of production. We recommend the following well specifications for the new well. The optimal diameter well for this production is 16 indies. This would enable installation of a 12-inch size pump (Driscoll, 1986). The well should be screened at a depth of approximately 75_to 115 feet. The exact screen depth should be determined by conditions actually encountered during drilling. Prior to selecting screen sizes, sieve analyses should be performed on aquifer materials collected from the aquifer. The well should be constructed of a steel casing which conforms to ASTM Designation A-53 or A-120 or AP1 standard specification 5A or 5L. A properly designed stainless steel screen should be installed. 8.3 Water Quality of New Production Well Unfortunately, the water quality in the Sparling Aquifer seems to be consistently high in iron, manganese and total organic carbon. Thus, we predict that any new well will have levels of these constituents comparable to those found in the Spading well, and will require treatment to meet drinking water standards. 8.4 Ongoing Monitoring Program We recommend that the City establish an ongoing aquifer monitoring program to help develop a better understanding of the Spading Aquifer. The following activities are recommended: · Measure groundwater levels on a monthly basis in monitoring wells MW-i, -2, and -3, well 3K-2 (Spigarelli well), and the Sparling well; and · Conduct an aquifer test using the new well after it is installed. In addition, any work to further delineate the aquifer would be invaluable. This would include such tasks as installing more monitoring wells and possible use of geophysical techniques. A:\SUMFINL.TRI 42 9/6/96 8.5 Aquifer Protection Program We also recommend that the City take action to protect the Sparling Aquifer. It is the highest capacity aquifer identified on the Quimper Peninsula and, as such, should be protected. Suggested measures to implement this recommendation are as follows: · Develop a wellhead protection program for the well(s).* The following are key steps in that process: ::: 1. Designate wellhead protection areas for the well. An initial map of recharge areas is presented in this report (Figure 12); work should be done to further d~fine the areas and designate time-of-travel zones. Take action to minimize potential contaminant sources in the recharge or wellhead protection areas. Initiate a public education campaign regarding groundwater. Education is one of the most effective tools for protecting groundwater. * Wellhead protection programs are required by the Washington Department of Health. A:\SUMFINL.TRI 43 9/6~96 List of Appendices A. Work Plan B. References C. Well Numbering Scheme D. Summary of Well Logs Compiled for this Study E. Monitoring Well Construction Details F. Analytical Laboratory Reports G. Aquifer Test Data Collection Sheet H. Development of Well Hydraulics Equations I. Aquifer Test Plots APPENDIX A W°rkplan TRI-AREA GROUNDWATER STUDY WORK PLAN FOR DRILL PROGRAM AND AQUIFER TEST Prepared for: The City of Port Townsend Prepared by: CH2M HILL March 19, 1996 TABLE OF CONTENTS 1.0 Introduction .................................................................. 1 2.0 Project Description ....................................................... 1 2.1 Project Background 2.2 Objective 2.3 Approach 3.0 Physical Setting ........................................................... 3 3.1 Sources 3.2 Geologic Setting 3.3 Local Geology and Water-Bearing Units 3.4 Surface Water 3.5 Preliminary Hydrogeological Evaluation 4.0 Drilling Program ......................................................... 6 4.1 Monitoring Well Placement 4.2 Drilling Methods 4.3 Well Installation 4.4 Water Level Measurements 5.0 Analytical Program .... ; ................................................ 8 5.1 Water Sampling Methods 5.2 Analytical Procedures 6.0 Aquifer Testing .......................................................... 8 6.1 Test Methods 7.0 Data Reduction and Analysis ..................................... 9 7.1 Hydrogeological Evaluation 7.2 Aquifer Test Analysis 7.3 Basin Yield Estimates 8.0 Estimated Schedule ...................................................... 10 APPENDICES A. References B. Well Numbering System D. Drilling Scope of Work E. Field Forms Page a:\qapp 3/20/96 LIST OF FIGURES Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Tri-Area Vicinity Map Site Area Map Geology of Tri-Area Boring Log of Sparling Well Section 3 Map Showing Proposed Monitoring Well Locations LIST OF TABLES Table 1 Table 2 Table 3 City of Port Townsend Groundwater Wells Description of Geologic Units Water Level Measurement Interval a:\qapp 3/20/96 1.0 INTRODUCTION This Work Plan was prepared by CH2M Hill for the City of Port Townsend (City). CH2M Hill was retained by the City to conduct a groundwater study in the Tri-Area of Jefferson County, Washington. The aim of the study is to recommend a location for a new groundwater production well. This Work Plan describes the objectives, activities, methodology, and data analysis procedures for the Tri-Area Groundwater Study. All activities are planned and will be conducted by qualified personnel following standard professional procedures and best professional judgement. ?' 2.0 PROJECT DESCRIPTION 2.1 Project Background The City of Port Townsend (City) supplies water to users in the Port Townsend and Tri-Area vicinities of Jefferson County (Figures 1 and 2). Tri-Area refers to the vicinity encompassing the towns of Chimacum, Hadlock and Irondale. Water supplies are currently obtained through a combination of surface water and groundwater sources. The City possess_es water rights for and currently produces from two groundwater production wells located in the Tri-Area. These wells are known as the Spading and the Kivley Wells. The well locations are shown in Figure 2. In order to meet current and projected water use, the City of Port Townsend plans to increase its production of groundwater utilizing the existing water right. The following factors will be weighed in recommendlng a location for a new groundwater production well in the Tri-Area: 1. Water rights; 2. Groundwater availability; 3. Potential impacts of increased pumping on Chimacum Creek; 4. Potential for pumping to cause seawater intrusion; and, 5. Water quality. Grofindwater Rights Situation The City has groundwater rights for the Sparling and Kivley wells, as outlined in Table 1. Current usa e and treatment capacity are also shown. Table 1: City of Port Townsend Groundwater Wells Source Right: Average Right: Peak Current Well Current Annual Flow Day (GPD) Capacity Treatment (GPD) (GPD) Capacity (GPD) Sparling Well 999,803 3,240,000 800,000 800,000 Kivley Well 142,829 288,000 100,000 0 GPD GPD TOTAL 1,142,632 3,528,000 900,000 800,000 Current Sparling well production is approximately 800,000 GPD. This is approximately a:\qapp 3/20/96 2,400,000 gallons per day less than the peak day water right. The City has applied to the Department of Ecology (Ecology) for an additional point of diversion to fully utilize, or perfect, this right. If granted, this would enable the City to pump water from another well located in the same source unit in order to achieve the total production allocated in the original water right. Current Washington regulations governing the construction of wells do not permit wells to be screened in multiple aquifers (WAC 173-160). Therefore, a new production well will need to be screened in a single aquifer. The Kivley well is also producing less than its total allocation. However, given that the under- utilized right of the Sparling well is much greater, the current study does not consider increasing production at the Kivley well. Groundwater Availability The potential yield of the well and basin are important factors in selecting the location for a new production well. Key factors affecting potential yield are the areal extent of the aquifer, its thickness, and the water-bearing properties of the unit. In addition, climatic factors such as precipitation and recharge also determine basin yield. Potential Impacts on Chimacum Creek Chimacum Creek lies approximately 750 feet east of the Sparling well. Chimacum Creek is a closed creek, that is, no new water withdrawals are permitted from the c-reek (Ecology, personal communication, 3/6/96). Therefore, it is important that pumping from a new groundwater production well not affect Chimacum Creek. The Chimacum Creek watershed, at 37 square miles, is the largest on the Quimper Peninsula. Chimacum Creek is one of the most productive coho salmon waterstieds on the northeast Olympic Peninsula. Chum salmon also run in the system. While WDF et al. (1993) reported that coho in Chimacum Creek were healthy, Bahls and Rubin (1996) reported that Chimacum coho were an "at risk population size." The creek is part of the Usual and Accustomed fishing grounds of the Port Gamble S'Klallam Tribe, reserved through the Point No Point T~eaty of 1855. Protecting in-stream flow from withdrawals due to groundwater pumping was also a concern mentioned in the Dungeness~Quilcene Water Resources Management Plan (1994). Potential fo~' Seawaterlnt~sion Seawater intrusion is a significant issue in the Quimper Peninsula vicinity, particularly for wells located near the coast which are completed at or below sea level. A new production well should be located where there is minimal risk of seawater intrusion. Water Quality_ The Sparling well produces water which contains high levels of iron and manganese. Typical levels for iron are 6 mg/L (milligrams per liter) and for manganese are 0.5 mg/L. The secondary MCLs (maximum contaminant levels) for these constituents are 0.3 mg/L and 0.05 mg/L, respectively. Currently, the groundwater produced from the well is treated at an on-site plant to reduce constituent levels prior to distribution. It would be ideal to find a source where these elements are present at lower levels than in the Sparling well. However, if the new well produces water containing high levels of iron and manganese, it will be treated to reach acceptable a:\qapp 2 3/20/96 concentrations. 2.2 Project Objectives The objectives of the current project are to: estimate the potential yield of a new groundwater production well; evaluate the impact of pumping on Chimacum Creek; evaluate the potential for seawater intrusion; estimate the water quality of a potential new well; provide data to use in delineating wellhead protection areas; and, recommend the location and depth of a new production well. 2.3 Project Approach Study Location The Sparling well vicinity is considered to be one of the best locations for a new production well for the following reasons: 1. The City already possesses a water right in the vicinity, currently being accessed through the Sparling well; no new water right would be needed; 2. The Spading well is one of the most productive wells in Jefferson County. A new production w611 in the vicinity would likely also be highly productive; and, 3. It is located in the middle of the Quimper Peninsula, in an area where bedrock appears to form a sor~ of natural barrier against seawater intrusionl For these reasons, the current groundwater study focuses on conditions near the Sparling well. Study Activities In or~ter to assess the extent and potential yield of aquifers in the Sparling well vicinity, the following activities will be conducted: 1. Drill and log three boreholes; 2. Install one nested monitoring well and two single-completion monitoring wells in the boreholes; 3. Measure water levels in monitoring wells and other nearby wells; and, 4. Conduct an aquifer test using the existing well and the monitoring wells. In addition, to evaluate the Water quality of the potential production well, water samples will be collected and analyzed for iron, manganese, and fecal coliform. The procedures and methods to be used to implement these activities are outlined in more detail in this work plan. 3.0 PHYSICAL SETTING 3.1 Sources a:\qapp 3/20/96 The information presented in this section was compiled from geologic reports, geologic maps, and logs of wells. Full references are cited in Appendix A. The well numbering scheme is based on township, range, section, quarter section, and quarter-quarter section. It is the same system employed by the US Geological Survey, Ecology, Washington Department of Natural Resources, and others. It is described in Appendix B. The well log information compiled by the Jefferson County Water Resources Committee uses a compatible and nearly identical system. 3.2 Geologic Setting The Tri-Area sits in the Puget Lowland between the Olympic Mountains to the west and the Cascade Mountains to the east. This area was subject to a series of glacial advances during the Pleistocene when ice advanced from and retreated to the Cordilleran ice sheet to the northeast. In the Sparling well vicinity, we see a bedrock upland where Anderson Lake is located, surrounded by a complex assemblage of glacial deposits (Figure 3). The pattern of glacial deposits is controlled by the topography, with bands concentric to the Anderson Lake upland falling out in the Chimacum Valley as it wraps northwest through the Four Comers area. At elevations above approximately 200 feet, the Vashon Lodgement Till is the uppermost unit. This is underlain by Advance Outwash deposits, which is exposed from elevations of approximately 140 to 200 feet. On the valley floor, below approximately 140 feet, Recessional Deposits are the surface unit. Recent alluvial deposits cover the glacial deposits in some areas near creeks. The geology is shown in Figure 3 with unit descriptions in Table 2. The majority of the glacial deposits in the Sparling area were laid down during the Vashon stade of the Fraser advance as the glacier advanced toward the southwest, depositing first the Advance Outwash, then dropping the till on the uplands, then, as it receded, laying down'the Recessional Deposits in the lowl/tnds. Within the Recessional Deposits, both outwash and ice-contact deposits have been mapped. The outwash tends to lie in the center of the peninsula, while the ice-contact deposits are located toward the seaward sides. The earliest deposits of the Advance Outwash are the Lawton Clay and the Pilchuck Clay members which Mullineaux and others (1965) described as chiefly dark-gray clay with light-gray silt. This is overlain by the Esperance Sand Member, which is a brown uniform medium sand grading downward to gray to brown, fine to medium sand interbedded with silty clay. Underlying the deposits of the Fraser Glaciation are older glacial deposits and transitional beds which were deposited between glaciations and by earlier glacial advances. All of the glacial deposits are highly variable laterally and vertically. 3.3 Local Geology and Water-Bearing Units According to geologic reports, the Sparling well site is located in an area where Recessional Outwash occurs at the surface. This is underlain by Advance Outwash deposits, Pre-Fraser units, and bedrock. Based on boring logs, it appears that till is also present in the study area. To the west of the Sparling well, at the base of the hill, Advance Outwash deposits are exposed at the a:\qapp 4 3/20/96 TABLE 2 DESCRIPTION OF GEOLOGIC UNITS After Pessl et al (1989), Grimstad and Carson (1981), Gayer (1976), and Mullineaux et al (1965). HOLOCENE Hb Beach sand Hs Swamp, marsh and bog deposits PLEISTOCENE Qvt, ¥1t Vashon Lodgement Till (Pessl et al) Poorly sorted mixture of rock fragments deposited directly by the Vashon-age ice sheet. Finercomponents include silt, sand, and clay in variable proportions, constituting a coherent to friable, moderately to highly compact matrix in which the coarser components (pebbles, cobbles, and boulders) are firmly embedded. The deposit is typically nonstratified, but subhorizontal layering and fissile structure are locally well developed; may contain lenses and pods of stratified sand, silt, and gravel. Thickness varies considerably but typically ranges from a few meters to as much as 40 m and probably averages between 3 and 15 m. In fresh exposures at depths greater than 1-2 m, the till matrix is light olive gray to gray; clay-rich till tends to have bluish-gray aspect, and weathering of the uppermost few meters typically has produced a matrix color of olive to buff. Qva, Vao Vashon Advance Outwash (Pessl et al) Sand; gravel, silt, and clay deposited by meltwater flowing from advancing ice margin of the Puget lobe of Vashon age; may also include the Esperance Sand, Lawton Clay, and Pilchu6k Clay Members of the Vashon Drift. Stratification generally dips southeast to southwest although cross-stratification and cut-and-fill structures are common. Where the entire thickness of the uhit is preserved, flat~lying fine sand, silt, and clay, ranging from nonlayered to thinly laminated, predominate in the lower part. The deposit locally becomes coarser upward and consists of moderately to poorly sorted, coarse to medium sand andgravel near the top. Thickness ranges from 1 to more than 60 m, averaging 10-20 m. Good examples-of the Vashon advance outwash deposits are preserved on the south and west parts of Camano Island, in seacliff exposures on north and east sides of Marrowstone Island, and in stream banks north and south of Stillaguamish River. This unit will yield moderate to large quantities of water where gravel and sand underlie zone of saturation. The Lawton Clay (Mullineaux et al, 1965) is a dark gray clay interbedded with light gray silt. The upper part is chiefly clayey silt; in part structureless, elsewhere laminated. Grades downward into finer grained beds typical of lower part. Lower part chiefly dark gray clay containing thin light gray silt layers. A few thick beds contain contorted laminations suggesting deposition by subaqueous slumping. Characterized by flattish calcareous concretions apparently formed in thin silt layers. Contains thin beds of sand near base. CFABLE 22, CONTINUED) Vro, Vrd Recessional outwash in meltwater channels and deltas (Pessl et al) Poorly to well-sorted, locally iron-stained sand, gravel, and silt deposited predominantly by meltwater from the receding Vashon-age ice sheet. Thickness commonly ranges from 2 to 10 m, but unusual thicknesses of 20-50 m are found as valley fills along major drainages. These deposits are associated with three principal depositional environments, each containing sediments with somewhat different characteristics: -' Ice Contact deposits-- Typically deposited in contact with masses of stagnant glacier ice; original stratification commonly dips 10° or less with local cut and fill structures; particle size and degree of sorting range widely; locally contains lenses and pods of glacially derived sediment-flow deposits, for example, flow till. Topographic expression commonly is hummocky with closed depressions and irregular ridges caused by collapse of the original sediment surface after melting of buried glacier ice. Collapse structures such as steeply tilted, contorted, and faulted layers are common. Outwash deposits--Deposited downvalley from the zone of stagnant glacier ice. Sediments are horizontally stratified to gently dipping with channel crossbeds and cut- and-fill structures. Deposits are typically composed of medium- to well-sorted, pebble- cobbie gravel and coarse to medium sand with local lenses of fine sand and silt. Topographic expression of outwash deposits, where not modified by erosion, is typically a relatively smooth surface with a gentle downvalley gradient. Alluvial fan deposits--Poorly to moderately well sorted, pebble-cobble gravel with boulders and lenses of finer materials deposited by swift-flowing streams coming from upland areas. Boulders, cobbles, and pebbles are angular to subround and are commonly derived from local sources. Some fans, built into lakes or marine waters, have large-scale deltaic foreset beds. Fan surfaces _slope valleyward at angles less than 15°, but individual layers may dip as steeply as 30°. Deposits range in thickness from 20 to 40 m and interfinger with and overlie the horizontally- layered outwash deposits_.. Unit yields small to large quantities of groundwater where it occurs in sufficient thickness below saturated zone. Qvl Qu Qpfn Vashon lacustrine deposits Undifferentiated Undifferentiated glacial, fluvial, glaciofluvial, lacustrine, and glaciotacustrine deposits: includes sediments resulting from pre-Fraser Glaciations (Possession Drift, Double Bluff Drift), interglaciation (Whidbey Formation), and advance outwash sands of the Fraser Glaciation. The sands and gravels of the pre-Fraser units are of varying permeability and areal extent and generally yield little or no water. Nonglacial Sedimentary Deposits of pre-Fraser Glaciation Age (Pessl et al) Fine-grained deposits of inter-bedded sand, silt, clay, and peat with minor lenses and thin layers of coarse sand and gravel. Layers of silt, clay, and silty sand are light gray to gray and contain layers of dark-brownish-gray to black peat and woody fragments (TABLE ;~, CONTINUED) as much as 1 m thick. Stratification ranges from indistinct to thin bedded and locally is highly deformed. Sand and silty layers are light gray to buff and locally contain highly deformed, finer grained layers. Well-sorted, iron-stained, locally iron-cemented gravel is found as minor channel deposits cut into finer grained sediments that are interpreted as predominantly flood-plain deposits of slow-flowing meandering streams flanked by shallow lakes and swamps. Deposits commonly form resistant near-vertical cliffs; maximum thickness is approximately 80 m. Unit may also variously inc'iude nonglacial sediments of the Olympia interglaciation, the Kitsap Formation, and the Whidbey Formation. Cg Thin drift over sandstone TERTIARY Tb Basalt Ti Other igneous rocks Tg Massive sandstone Tc Conglomerate surface. Presumably, they extend to depth, where they are underlain by Pre-Fraser deposits and bedrock. Well logs in the Sparling well area (Figure 2) show a profile of approximately 50 feet of dense mixed silt, sand, gravel and clay, which is commonly referred to as "hardpan." Underlying the hardpan, in wells 3L, 3K-2, and the Sparling well, 3K-1 (Figure 4), is a sequence of sands, gravels, and clays which extends to a depth of approximately 124 feet. This is the unit we refer to as the Upper Water-Bearing Unit. While it is possible that the Upper Unit contains distinct water-bearing lenses, there is not enough information to determine their extent or level of interconnection. A thick blue clay bed underlies the Upper Unit. The blue claY extends to a depth of 158 feet, interrupted only by one thin sand seam. It is probable that this blue clay unit is the Lawton Clay Member, the basal unit of the Advance Outwash deposits. A thick blue or gray clay, possibly the same unit, is noted in numerous well logs throughout the study area. Underlying the blue clay is another water-bearing sequence of sand and gravel, which continues in the Sparling well to a depth of about 178 feet. We refer to this as the Lower Water-Bearing Unit The depth to bedrock at the site is unknown. However, three miles south of the site, Grimstad and Carson (1981) mapped the depth to bedrock at approximately 20 to 50 feet above sea level, based on well logs in that area. According to Grimstad and Carson (1981), the Spading well was the highest yielding production well in eastern Jefferson County. During a pump test, it produced a specific capacity of 125 gpm per foot of drawdown. Well 3J, one half-mile south of the Sparling well, was also highly productive. The autt~ors postulate that the aquifer these wells tap was "laid down by a fast- flowing glacial stream which winnowed out the fines, leaving a porous and permeable unit capable of storing and transporting large quantities of water." They also point out the high degree of variability in this area, as other wells drilled nearby had specific capacities of 2.2 gpm to 4 gpm per foot of drawdown. 3.4 Surface Water Ch-i-macum Creek lies approximately 750 feet east of the Sparling well site. From that point, it flows north-northwest for approximately one mile to a bend where the creek tums to the east and flows out to Puget Sound. Rubida (1989) measured flow in Chimacum Creek over a one year period (2/88-2/89) at a site approximately 0.75 miles north (downstream) of the Sparling site. A low flow of 4.81 cfs (cubic feet per second) was measured in August, while a high flow of 14.54 cfs was measured in January of 1989. Bahls and Rubin (1995) had two sites (2&C) located nearly due east of the Sparling well. They measured a variety of parameters in their study. They concluded that these sites had suffered low loss of summer, winter, and spawning habitat. Based on comparisons of elevations in Chimacum Creek and the water-bearing units in the wells, it is possible that the Upper Unit is in some degree of hydraulic connectivity with the creek. a:\qapp 5 3/20/96 3.5 Summary - Preliminary Hydrogeological Evaluation Local Aquifers Well logs indicate that there are two primary water-bearing units in the vicinity of the Sparling well, the Upper Unit, and the Lower Unit. The Upper Unit extends from a depth of approximately 50-65 feet below ground surface to the thick blue clay unit found at about 125 feet. This unit is tapped by several area wells. It is a confined aquifer consisting of a sequence of mixed deposits, many of which bear water. While these deposits may represent different aquifers, at present, there are not sufficient data to differentiate them. Below the thick blue clay layer, at a depth of approximately 160 feet in the Sparling well, is the Lower Water Bearing Unit. This is also a confined aquifer. Groundwater Flow Direction and Gradient At present, there is little to no information available on groundwater flow directions or gradient. We presume that the general groundwater flow direction is north to northeast, radiating from the Anderson Lake upland and parallel to Chimacum Creek. That is also the flow direction portrayed in the East Jefferson County Groundwater Study (EES & PGG, 1994). 4.0 DRILLING PROGRAM 4.1 Monitoring Well Placement In order to obtain data to achieve the study objectives, the monitoring wells described below will be installed. The approximate locations are shown in Figure 5. Well details outlined here are best judgements and may change based on conditions actually encountered in the field. One nested nionitoring well cluster will be installed approximately fifty to one hundred feet from the Sparling production well. Prior to well installation, the boring will be advanced to bedrock, or a maximum depth of 250 feet, in order to obtain information for the hydrogeologic evaluation. Two two-inch monitoring wells will be installed in the borehole following the methods outlined below. One well will be completed in the -' Lower Unit, the other will be completed in the Upper Unit. These wells will enable data collection during the aquifer test for evaluation of aquifer parameters. A single completion monitoring well will be installed approximately half-way between the Sparling well and Chimacum Creek. This well will be completed in the Upper Water- Bearing Unit. This well will provide data to help assess the effects of increased production on groundwater baseflow to the creek. An additional monitoring well will be installed west of the Sparling well to help evaluate the lateral extent and thickness of the units. This well will be completed in the Upper Unit. It will provide data to evaluate aquifer parameters and groundwater flow directions and gradients. This well may also prove to be useful as a test well for the new production well. The nested well close to the Spading well will be installed first so that water levels in the two units may be measured and used to finalize the placement of the other wells. 3/20/96 a:\qapp , 4.2 Drilling Methods The borings will be drilled and the wells installed using a cable tool drill rig. Prior to drilling, the well locations will be cleared with all utilities by CH2M Hill. The Port Townsend Department of Public Works will obtain permission for drilling all monitoring wells from the appropriate landowners. Tacoma Pump and Drill will be sub-contracted for the drilling. (See attached Drilling Scope in Appendix C). A CH2M Hill hydrogeologist will be on-site during drilling to log the materials .encountered in the borings and to supervise drilling and monitoring well installation. All drill tools will be cleaned prior to drilling. The driller will notify Washington Dept. of Ecology of the drilling operation at least seventy-two hours before drilling commences. As the boring is advanced, a temporary casing will be driven into the hole to keep it from collapsing as drilling proceeds. The borehole in which two wells are to be installed will be eight inches in diameter. The single completion boreholes will be six inches in diameter. Formation samples will be collected at five foot intervals by driving a sampler ahead of the drill s{em and retrieving samples to the surface for lithologic logging. Samples will be logged using USCS (Universal Soils Classification System) terminology by the on-site hydrogeologist. Borehole lithology will be recorded on the boring log forms attached in Appendix D. Drill cuttings will either be distributed at the site by the drill contractor or will be disposed of by Public Works. 4.3 Monitoring Well Installation The monitoring well~ will be installed in the borehole following drilling. The temporary drill casing will be retrieved as the well materials are installed to ensure full contact between the formation and the well materials. Wells will be constructed in accordance with WAC 17-3-160, Minimum Standards for Construction and Maintenance' of Resource Protection Wells. The wells will be constructed of two-inch Schedule 40 PVC. Each well will have a five foot silt trap with a bottom cap on the bottom. Wells will be equipped with 20 (0.020) slot PVC screens five to ten feet in length depending on the formation. A size 16/30 Colorado silica sand pack will be installed in the annulus surrounding each screened interval to at least three feet above the top of the screen. A bentonite chip seal at least two feet thick will be emplaced above the filter pack, and the borehole grouted to the surface. In multiple completion wells, the piping shall be held in place by centralizers to ensure that a complete seal forms around each well. Care will be taken during installation of the nested wells'to provide complete separation between the lower and the upper wells. Locking steel casings will be cemented in place at the surface of each borehole, and guard posts will be installed as required by law. Exact well construction and materials will be documented during installation by the CH2M Hill on-site hydrogeologist. Construction will be recorded on the boring log. Following installation, each monitoring well will be surveyed by registered surveyors to establish the elevation of the casing to within 0.01 foot relative to sea level. Wells will be developed by surging and bailing until the water produced is clear. a:\qapp 3~0~6 4.4 Water Level Measurement Water levels will be measured in monitoring wells using an electronic water level device. Levels will be measured immediately following well installation and periodically after that until it is clear that water levels have stabilized. Measurements will be taken by measuring the depth to water from the marked and surveyed measuring point until two successive measurements provide a reading to within 0.01 foot. 5.0 ANALYTICAL PROGRAM z 5.1 Sample Collection and Handling Samples will be collected from each of the monitoring wells for analysis of iron, manganese, and total coliform. Prior to collecting water samples, monitoring wells will be purged by bailing or pumping two to three well volumes. Samples will then be collected using a clean stainless steel bailer affixed to new 100 pound test monofilament. Samples will be decanted into clean sample bottles supplied by the laboratory and will be preserved as follows as required by the method: · Iron and Manganese: fixed with HNO3 Total coliform: fixed with sodium thiosulfate. Samples will be stored on ice and shipped immediately to the analytical laboratory for analysis within 24 hours of sample collection. Sample collection will be timed such that samples arrive at the laboratory prior to noon on Thursday, since the laboratory will not accept total coliform samples after 3PM on Thursdays. No quality control s~imples will be collected. 5.2 Analytical Methods Samples will be analyzed by Sound Analytical Laboratory in Tacoma. Iron and manganese samples will be analyzed using EPA Method 200.7, a drinking water analysis using ICP. Total coliform will be analyzed using Standard Method 9222B, membrane filtration. 6~0 AQUIFER TESTING 6.1 Aquifer Test Methods The aquifer test will use the Spading well as the pumping well. It will be pumped at approximately 500 to 600 gpm for a period of approximately 24 hours. The exact discharge will be measured by the existing flow meter installed on the well. Pumped water will be piped into the storage and distribution system. Aquifer test data will be plotted during the test to enable real-time observation of boundary or other effects in the well. Water levels will be monitored before (baseline), during, and after pumping (recovery) in the pumping well and all of the monitoring wells, according to the schedule outlined below. Water level measurements will be collected using electronic equipment (data loggers and pressure transducers) for the pumping well and both monitoring wells in the nearby nested cluster. Additional water level measurements will be recorded manually using electronic water level a:\qapp 3/20/96 tapes. Prior to beginning the aquifer test, the watches of all personnel collecting data will be synchronized. Once the pump is shut off, measurements will be taken until all wells have recovered. If water levels have not recovered within 24 hours, the termination time will be determined based on best professional judgement. a:\qapp 3/20/96 TABLE 3 WATER LEVEL MEASUREMENT INTERVAL (after Driscoll, 1986, p353) For Pumping Well: Time since pumping started or stopped Time interval between measurement in minutes, in minutes 0-10 0.5-1 10-15 1 15-60 5 60-300 30 .~-~ 300-termination 60 For Observation Wells: Time since pumping started Time interval between measurement jn minutes in minutes 0-60 2 60-120 5 120-240 10 240-360 30 360_termination 60 _7.0 DATA REDUCTION AND ANALYSIS 7.1 Hydrogeological Evaluation Site hydrogeologic conditions will be 6valuated by considering boring logs, water levels, aquifer test data, water quality results, information available through existing Well logs and geologic reports, and other av~tilable information. The information collected during the field program will be used to refine the preliminary hydrogeologic assessment presented in this Work Plan. 7.2 Aquifer Test Analysis Aquifer test results will be analyzed by making plots of time versus drawdown and distance versus drawdown for evaluation of aquifer parameters and assessment of boundary and other effects. Electronic data will be downloaded into a spreadsheet for reduction and analysis. 7.3 Basin Yield Estimates Expected well and basin yield will be estimated using the following methods: water budget; analytical solution based on Darcy's law and well hydraulics; specific capacity analysis. The yield estimates will use aquifer parameters and hydrogeological information obtained through monitoring well installation and testing, and the aquifer testing. a:\qapp l0 3/20/96 8.1) ESTIMATED SCHEDULE We anticipate following the schedule outlined below to conduct activities described in this Work Plan. This schedule could vary depending on circumstances actually encountered in the field or in logistical preparations for field work. ESTIMATED SCHEDULE · Drilling and Well Installation April 15 - May 10 ~.-, · Water Quality Sampling May 3 - May 10 · Aquifer Test May 13 - May 24 ' · Aquifer Test Analysis May 13 - May 31 · Summary Report Draft June 15/Final July 15 a:\qapp 3/20/96 FIGURE 4 BORING LOG OF SPARLING WELL Topsoil Hardpan with coarse gravel DEPTH.(feet) 0 - 4, APPROX. ELEVATION (ft above msl) NOTES 125 Hardpan with gravel and boulders 20 40 Hardpan with fmer , /. / ? gravel, softer ///: 105 85 Water level Fine sand with some water Heaving sand 60 .,:.,:. 65 Coarse sand, water Peat Upper Water- Heaving sand Bearing Unit. Cla~ . x~ 45 Coarse gravel ~ :-~ ~ - Heaving sand ~ :,~ ~ Medmm gravel wtth ~ ~ mixed sand - ,o~ ~. _ Pea gravel, water-bearmg ,;~.~ ' Medium sand and gravel ~ with some clay, hard _ _ _ _--r.-7_~._~7-~.~_~ ~ xx ...... ~-~ ~~...~ 5 ~ ~ Screened Clay and gravel yam water ~z .s,"'~':- '~' ;"-~':.~. " ~N Uo~se s~a ~o grave~ ~ ~ ~ ~< ~ ~ B l ueclay ~~ ~ ~55 ~d pea ~avel 16~~5 ~::~: Clay ~d s~d ;.:.. :~':~':'C~ - :~' ""~&~" [ Tm-A~A GRO~DWATER S~Y Clay ~ -55 CH2M HILL 18( ~~_. '\ / ," APPENDICES Appendix A References Bahls, P. and J. Rubin, 1996 (Draft). Chimacum Watershed Coho Salmon Habitat Restoration Assessment. Prepared for Port Gamble S'Klallam Fisheries Office, Kingston, WA. Jamestown S'Klallam Tribe, 1994. The Dungeness-Quilcene Water Resources Management Plan, 1994. Prepared by the Tribe as Coordinating Entity for the Regional Plarming Group. Driscoll, F.D., 1986. Groundwater and Wells, Second Edition, Johnson Division. Economic and Engineering Services, Inc. and Pacific Groundwater Group, 1994. Eastern Jefferson County Groundwater Characterization Study. Prepared for Public Utility District No. 1 of Jefferson County. Freeze, R.A., and J. A. Cherry, 1979. Groundwater, Prentice-Hall, Inc: Gayer, M.J., 1976. Geologic Map of Northeastern Jefferson County, Washington. Washington Dept. of Natural Resources, Map OFR76-21. - Grimstad, P. and R.J. Carson, 1981. Geology and Ground-Water Resources of Eastern Jefferson County, Washington. Water Supply Bulletin No. 54. Washington Dept. of Ecology in cooperation with Washington Dept. of Natural Resources Div. of Geology and Earth Resources. Mullineaux, D.R., H~ H. Waldron, and M. Rubin, 1965. Stratigraphy and Chronology of Late Interglacial and Early Vashon Glacial Time in the Seattle Area, Washington. USGS Bulletin 1194-0. Pessl, F., Jr., D.P. Dethier, D.B. Booth, and J. Minard, 1989. Surficial Geologic Map of the Port Townsend 30- by 60- minute Quadrangle, Puget Sound Region, Washington. USGS Map I- 1198-F. Rubida, Pat, 1989. Final Report Jefferson County Ambient Water Quality Report, for Washington State Department of Ecology. WDF, et. al, 1993. Washington Department of Fisheries, Washington Department of Wildlife, and Western Washington Treaty Indian Tribes, 1993. 1992 Washington State Salmon and Steelhead Stock Inventory. a:\qapp 12 3/20/96 APPENDIX B Well Numbering System The well numbering system used in this study is the same used by the US Geological Survey, the Washington Dept. of Ecology, and others. It is compatible with and nearly the same as the system used for well logs compiled in the Dungeness-Quilcene Water Resources Management Planning Process. Wells are numbered according to township, range, section, quarter-section (Q),:?and quarter- quarter (QQ) section. QQ section lettering is designated according to standard practice, as shown in the attached figure. If there is more than one well in a given QQ section, an additional' number is assigned each well following the QQ letter. This last number is assigned arbitrarily, but is unique. Ail of the wells in the study area are within two township and range groupings: T29N R1W, and T30N R1W. Thus, the township and range are not listed on the map. The numbers plotted on the map refer only to the section, Q and QQ sections. For example, the Spading well, numbered 3K-l, is located in section 3 ofT29N R1W. Within section 3, it is in the quarter-quarter kection identified as K. Since there are two well logs located in QQ section K, each is given an additional number. Well placement on the map is not exact. Many of the points are located on the correct parcel. Many however, are not accurate beyond QQ section. In those cases, the well is plotted in the center of the QQ section. Furthermore, well locations were not field-verified. Thus, original errors in reporting well locations may have gone undetected. NW NE NW NE NW NW NE NE D C B A 40 ACRES 40 ACRES 40 ACRES 40 ACRES SW SE SW SE NW NW NE NE E-- F G H 40 ACRES 40 ACRES 40 ACRES 40 ACRES NW NE NW NE SW SW SE SE M L K J 40 ACRES 40 ACRES 40 ACRES 40 ACRES SW SE SW SE SW SW SE SE N p Q R 40 ACRES 40 ACRES 40 ACRES 40 ACRES SUBDIVISIONS OF A SECTION a:\qapp 13 3/20/96 APPENDIX C Drilling Scope TRI-AREA HYDROGEOLOGICAL STUDY DRILLING SCOPE OF WORK FOR CH2MHILL, PORT TOWNSEND DATE: MARCH 19, 1996 JOB LOCATION: Near Chimacum, approximately 1/2 hour south of Port ToWnsend' Washington. T29N R1W, NW of SE (K) of Section 3 -~ APPROXIMATE START DATE: APRIL 15, 1996 CONTACT: JEAN BODEAU, Tel. (360) 385-2413, Fax (360) 379-5177 ESTIMATED SCOPE OF WORK - ACTUAL DRILLING MAY BE SLIGHTLY MODIFIED DEPENDING ON CONDITIONS ENCOUNTERED IN FIELD. DRILLING DETAILS Drill 3 boreholes and install monitoring wells as follows: 1. Drill one eight inch boring to bedrock at approximately 200 - 230 feet. Install 2 separate monitoring wells in the borehole, with completions at approximately 170 feet and 100 feet. 2. Drill one six-inch boring to approximately 125 feet, installing one monitoring well with bottom depth between 80 and 120 feet. 3. Drill one six inch-boring to approximately 100 feet, installing one monitoring well with bottom depth between 70 and 100 feet. -Drilling to be by cable rig -Split spoon sampling at five foot intervals on borings as requested by geologist -Rig to be clean but not steam-cleaned WELL COMPLETION DETAILS - DRILLER TO SUPPLY ALL MATERIALS: 2 inch Schedule 40 PVC pipe 2 inch Schedule 40 20 slot PVC well screen, 5 foot sections 5 foot sumps on each well Clean silica sand - grade #16/30 or similar Bentonite chips Grout 3 stainless steel centralizers for each multiple borehole Above-ground locking stell monuments to be installed in concrete pad OTHER PROVISIONS Driller to notify Ecology of drilling at least 72 hours before drilling is to commence Utility locates will be conducted by client See contract a:\qapp 14 3/20/96 INSURANCE REQUIREMENTS As listed in contract APPENDIX D Field Forms Attached a:\qapp 3/20/96 PROJECT NUMBER I BORING NUMBER SHEET OF SOIL BORING LOG LOCATION PROJECT ELEVATION DRILLING CONTRACTOR DRILLING METHOD AND EQUIPMENT START FINISH LOGGER WATER LEVELS ........ SOIL DESCRIPTION COMMENTS ~ ~.. SAMPLE STANDARD PENETRATION O, ~ >' TEST LU O:: SOIL NAME, USCS GROUP SYMBOL, COLOR. DEPTH QF CASING, DRILLING RATE, rce._ LU MOISTURE CONTENT, RELATIVE DENSITY DRILliNG FLUID LOSS, a~ ~ ~ESULTS ~ DJ>- rr' ,-n ~ O OR CONSISTENCY, SOIL STRUCTURE, TESTS AND INSTRUMENTATION P'" LU :~ Oh 6"-6"-6" MINERALOGY REV 11/89 FORM 01586 {8.30) APPENDIX B References Bahls, P. and J. Rubin, 1996 (Draft). Chimacum Watershed Coho Salmon Habitat Restoration Assessment. Prepared for Port Gamble S'Klallam Fisheries Office, Kingston, WA. Crandell, 1965. Age and Origin of the Puget Sound Trough in Western Washington. U.S. Geological Survey Professional Paper 525-B, Pages B 132-B 136. Doraiswamy, Paul C, 1977. The Radiation Budget and Evapotranspiration ora Douglas-Fir Stand. University of Washington Ph.D. Dissertation. Driscoll, F.D., 1986. Groundwater and Wells, Second Edition, Johnson Division. EES & PGG, 1994. Economic and Engineering Services, Inc. and Pacific Groundwater Group, Eastern Jefferson County Groundwater Characterization Study. Prepared for Public Utility District No. 1 of Jefferson County. Freeze, R.A., and J. A. Cherry, 1979. Groundwater, Prentice-Hall, Inc. Gayer, M.J., 1976. Geologic Map of Northeastern Jefferson County, Washington. Washington Dept. of Natural Resources, Map OFR76-21. Grimstad, P. and R.J. Carson, 1981. Geology and Ground-Water Resources of Eastern Jefferson County, Washington. Water Supply Bulletin No. 54. Washington Dept. of Ecology in cooperation with Washington Dept. of Natural Resources Div. of Geology and Earth Resources. The Dungeness-Quilcene Water Resources ManagementPlan, 1994. Prepared by the Tribe as Coordinating Entity for the Regional Planning GrouP. -- Mullineaux, D.R., H. H. Waldron, and M. Rubin, 1965. Stratigraphy and Chronology of Late Interglacial and Early Vashon Glacial Time in the Seattle Area, Washington. USGS Bulletin 1194-0. Newcomb, R.C., 1952. Ground-Water Resources of Snohomish County Washington. U.S. Geological Survey Water-Supply Paper 1135. __ Pessl, F., Jr., D.P. Dethier, D.B. Booth, and J. Minard, 1989.-Surficial Geologic Map of the Port Townsend 30- by 60- minute Quadrangle, Puget Sound Region, Washington. USGS Map I- 1198-F. Rubida, Pat, 1989. Final RePort Jefferson County Ambient Water Quality Report, for Washington State Department of Ecology. Simpson, James Robert, 1983. Predicting Evapotranspiration, Leaf Resistance and Soil Water Budget for a Douglas-fir Forest. University of Washington Ph.D. Dissertation. Thorson, Robert M., 1981. Isostatic Effects of the Last Glaciation in the Puget Lowland, Washington. U.S. Geological Survey Open-File Report 81-370. USWB, 1965. Mean Annual Precipitation, 1930-57, State of Washington: Portland, Map M- 4430. WDF, et. al, 1993. Washington Department of Fisheries, Washington Department of Wildlife, and Western Washington Treaty Indian Tribes, 1993. 1992 Washington State Salmon and Steelhead Stock Inventory. APPENDIX C Well Numbering System Well Numbering System The well numbering system used in this study is the same used by the US Geological Survey, the Washington Dept. of Ecology, and others. It is compatible with and nearly the same as the system used for well logs compiled in the Dungeness-Quilcene Water Resources Management Planning Process. Wells are numbered according to township, range, section, quarter-section (Q), and quarter- quarter (QQ) section. QQ section lettering is designated according to standard practice, as shown in the attached figure. If there is more than one well in a given QQ section, an additional number is assigned each well following the QQ letter. This last number is assigned arbitrarily, but is unique. All of the wells in the study area are within two township and range groupings: T29N RlW, and T30N R1W. Thus, the township and range are not listed on the map. The numbers plotted on the map refer only to the section, Q and QQ sections. For example: the Sparling well, numbered 3K-l, is located in section 3 ofT29N R1W. Within section 3, it is in the quarter-quarter section identified as K. Since there are two well logs located in QQ section K, each is given an additional number. - Well placement on the map is not exact. Many of the points are located on the correct parcel. Many however, are not accurate beyond QQ section. In those cases, the well is plotted in the center of the QQ section. Furthermore, well locations were not field-verified. Thus, original errors in reporting well locations may have gone undetected. NW NE NW NE NW NW NE NE D C B A 40 ACRES 40 ACRES 40 ACRES 40 ACRES · SW SE SW SE NW NW NE NE E F G H 40 ACRES 40 ACRES 40 ACRES 40 ACRES NW NE NW NE SW SW SE SE M L K J 40 ACRES 40 ACRES 40 ACRES 40 ACRES SW SE SW SE SW SW SE SE N- p Q R 40 ACRES 40 ACRES 40 ACRES 40 ACRES SUBDMSIONS OF A SECTION APPENDIX D Summary of Well Logs Compiled for this Study < ~ ~o1~o~~ ~o~o®~ooo~ooo~o~o 0 ~~&~ ~~ o~o~o~o,o~o~~ ~ 0 0 0 0~ ~ ~ ~ ~ ~ 0 ~ ~ ~ 0 ~:~ ~ ~ - Z~o~ Z ~ ~1 ~:~ Z ~ ~ ~ Z Z Z ~ Z ~ ~ Zzlz z ~ z Z ~;Z Z Z ~ APPENDIX E Monitoring Well Construction Details  PROJECT NUMBER .~ IBORING NUMBER ~ I/~/~' ~' ~' ~/~/-I ~, o~, ~ I WELL COMPLETION DIAGRAM I ELEVATION ~ ' - DRILLING CONTRACTOR: Z~ ~U ~ D ~( ~', [ ~ DRILLING METHOD AND EQUIPMENT USED :~E ~[ ~ I 3J 1- Ground elevation at wetl 2- Top of casing elevation a) vent hole? al wee. ho,e; ~/~,~ b) soncrete pad ~im~nsions 4-' Diameter/type of well casing 6 Diameter/type of surface casing el Quantityu, ed /~ ~-ro- 0 ~ c~ lO c) Quantity of w~ll casing grout Development time Estimated purge volume ABVSCW£L,XL5 IPROJECT NUMBER , IBORING NUMBEF~ ~ I WELL COMPLETION DIAGRAM I PROJECT :'Ta~-~ C'qP-~ ~h-Yr~-~Z. ~ Y ~o~.~,o. = ~ ~ ~- (~ ~c ~ M ELEVATION: DRILLING CONTRACTOR ~ ~ ~I)~P ~ ~ I~ EQUIPMENT USED :~C~D~ ~1~- ~1~ ,,~ ~JYC~ . DRILLING METHOD AND ' START: ~/~/fi~ ENo= ~J~t~ LOGGER: ~ ~0 ~ATER LEVELS: ',, . 3/ 1- Ground elevation at well 2- Top of casing elevation a) vent hole? Type screen filter b) Method of pla~men~ c) Quantity of well casing grout Development method Development time Estimated purge volume ABVSCVV~L.XL5 [PROJECT NUMBER~ I ~ I WELL COMPLETION DIAGRAM I :_LEVATION: DRILLING CONTRACTOR: '~'P~._~A.~. '~{~'~ ~ ?~f-~ I 4.(..- DRILLING METHOD AND EQUIPMENT USED WATER LEVELS: START LOGGER: 3f 1- Ground elevation at well 2- Top of casing elevation a) vent hole? a) weep hole? b} concrete pad dimensions 4- Diameter,typeofwe"o~s~ng ~ /~,~ ,~/9~d~,le h/~9 P~, 5- Oiameter/typ~ of surface casing 7- Type screen filter Type of seal Grout b) Method of ~) QuantEy of well casing grout Development method Development time ABV$CWELXL5 APPENDIX F Analytical Laboratory Reports SOUND ANAI.YTICAI SERVICES, INC:. ANALYTICAL & ENVIRONMENTAL CHEMISTS 4813 PACIFIC H/GHWAY EAST, TACOMA, WASHINGTON 9M24 - TELEPHONE (206)922-2310 - FAX (206)922-5047 Report To: CH2M Hill - Port Townsend Date: May 16, 1996 Report On: Analysis of Water Report No.: 56640 IDENTIFICATION: Samples received on 05-15-96 Project: 315187.MN.ZZ Tri Area Groundwater ANALYSIS: Lab Sample No. 56640-1 Parameter Total Organic Carbon Client ID: MW-1 General Chemistry Units: mg/L Method Result -PQL EPA 415.1 3.5 1.0 Parameter Iron Manganese ICP Metals Per EPA Method 200.7 - Date Analyzed: 5-15-96 Units: mg/L Result PQL 6.7 0.10 0.66 0.015 PQL - Practical Quantitation Limit 2 Th eport is issued solely for the use of the person or company to whom it is addressed. This laboratory accepts responsibili~ only for the duc performance of analysis in accordaace with inc, :ri acceptable praO. ke. In no even% ahall Sound Analytical Sewiccs, Inc. or its employees be re~pomibte for consequential or special damages in any k/nd or in any amount. SOUND ANAI XTICAL SERVICES, INC. CH2M Hill - Port Tonwsend Project: Tri-Area Groundwater Report No. 57004 June 7, 1996 Lab Sample No. 57004-2 Parameter Total Organic Carbon Client ID: MW-2 General Chemistry Units: mg/L Method EPA 415.1 Result 17 PQL 1.0 ICP Metals Per EPA Method 200.7 Date Analyzed: 6-3-96 Units: mg/L Parameter Result Iron .15 --Manganese 0.49 POL- O .20. 0.015 Total Coliform per Method SM 9221A Date Analyzed: 6-3-96 Parameter Result Total Coliform, MPN/ml 1,700 ND - Not Detected PQL - Practical Quantitation Limit Dri .,.port is issued solely for the use of the person or company to whom it is addressed. This laboratory accepts responsibility only for Ibc due performance of analysis in accordance with Lnd, _fy acceptable practice. In no event shall Sound Analylical Services, Inc.. or its employees be responsible for consequential or spedal damages in any kind or in any amount. SOUND ANAT.YTICAT. SERVICES, INC. ANALYTICAL & ENVIRONMENTAL CHEMISTS 4813 PACIFIC HIGHWAY EAST, TACOMA, WASHINGTON' 98424 - TELEPHONE (206)922-2310 - FAX (206)922-5047 Report To: CH2M Hill - Port Townsend Report On: Analysis of Water Date: June 7, 1996 Report No.: 57004 IDENTIFICATION: -Samples received on 05-30-96 Project: Tri-Area Groundwater ANALYSIS: Lab Sample No. 5.7004-1 Client ID: MW-3 General Chemistry Units: mg/L Parameter Method Total Organic Carbon EPA 415.1 Result' 94 ICP Metals Per EPA Method 200.7 Date Analyzed: 6-3-96 Units: mg/L Parameter Result Iron 150 Manganese 3.0 POL 0.20 0.015 PQL 1.0 Total Coliform per Method SM 9221A Date Analyzed: 6-3-96 Parameter Result Total Coliform, MPN/ml 500,000 ND - Not Detected PQL - Practical Quantitation Limit hi ~fl ~ ~u~ ~[e~ ~r the ~ of the ~n or ~mp~y to whom it ~ addressed. ~ Ia~mto~ a~ r~iH~ on~ ~r the due ~r~an~ of ~a~ ~ ac~rdan~ ~th ind~,~ry acceptable pra~. In no ~ent sh~ ~und ~a~i~l ~, Inc or i~ empl~ ~ ~ible ~r ~mcquenlial or s~ial ~mag~ in a~ ~nd or ~ ~ amo~t SOUND 'ANALYTICAL SERVICES, INc. ANALYTICAL & ENVIRONMENTAL CHEMISTS 4813 PACIFIC HIGHWAY F_Ab~, TACOMA, wASHINGTON 98424 - TELEPHONE (206)922-2310 - FAX (206)922-5047 Report To: CH2M Hill - Port TownSend Report On: Analysis of Liquid Date: June 13, 1996 Report No.: 57219 IDENTIFICATION: ~Samples received on 05-15-96 & 05-30-96, reference lab report numbers 56640 & 57004. Request for additional analysis received on 06-10-96. Project: Tri Area Groundwater ·ANALYSIS: Lab Sample No. 57219-1 Client ID: MW'i Dissolved Metals Per EPA Method 6010 Date Analyzed: 6-11-96 Units: mg/L Parameter Result ~ Iron ND 0.!0 Manganese 0°67 0.015 ND'- Not Detected PQL -' Practical Quantitation Limit el>OR ia hsued solely for the uae of the person or company t6 whom it is addre---~sed- This laboratory accepts respons~ility only for the due performance of analysis ia accordance with .na~] acceptable prance. In no event shall ,Sound Ana~ical ~t~icea, Inc. or its employees ~ ~esP~ns~le [or conv:qucntial or special damages in any kind or ia any amount SOUND kNALYT CAT. SERVICES, INC. CH2M Hill - Port Townsend ProjeCt: Tri Area Groundwater Report No.'57219 June 13, 1996 Lab Sample No. 57219-2 Client ID: MW-2 Dissolved Metals Per EPA Method 6010 Date Analyzed: 6-11-96 Units: mg/L Parameter Result PQL IrO~ 0.63 0.10 ,Manganese 0.39 0.015 ND -.Not Detected PQL - Practical Quantitation Limit ~i~ port is issued solely for the use °f the P~rs°u °r c°mpany t° wh°m it Is addressed' This lab°mt°U ac~ ~ili~ 9n~ f°r the due ~ff°mn~ °f ~N ~ a~ ~ ndL_.v acceptable practice. In no event shall Sound Analytical Serdces, lnc. or its emplo~x's be responsible for consequential or special damages in any kind or in any amount. SOUND ANAt.YTICAL SERVICES, INC. CH2M Hill - Port Townsend Project: Tri Area Gr0undwater Report No. 57219 June 13, .1996 Lab Sample NO. 57219-3 Client ID: MW-3 Dissolved Metals Per'EPA Method 6010 Date Analyzed: 6-11-96 Units: mg/L Result P-~ Parameter 9.5 _0.10 Irofi - 0 015 ~Manganese 0.30 · ND - Not Detected PQL - Practical Quant~tation Limit 4 ~ eport i$ t.~ued ~lely for the use ofthe person or company to whom iris addressed. This laboratory accepts responsibility only for the due performance of analysis in accordance with iae. c~.ry ~cceptable pmctlc~, la no event ~;hall Sound Analytical Setvic.~ lac or Its employe~ be responsible for coe, sequenlial or special d,ama~.e~ in any kind or in any amount. STATE' OF WASHINGTON . .-:.~WATER BACTERIOLOGICAL. ANALYSIS -' &AMPLE COLt~CTIOfl: READ INSTRUCTIONS ON BACK OF GOLDENROD COPY If Instruoaon~ are not followed, =ample will be rejected, · i. DATE COLLECTED ~ .I TIME~CTED 'l COUNTY. NNVlE ~:' '. -'NAME'OFSYST~EM . · - '-'. SPEC FiC LOCA~ON WH~F~ SAMPLE COU. ECTEDI TELEPHONE NO. ~ R~Name) .~ SYSTEM OWNER/MGR.: (Name) ' IRCE TYPE- :GROUND WATER UNDE~R SURFACE INFLUENCE ~ :ITl sUrFAcE I-~WELL or [] SPRING [] ._PURC__HA_SED or C~RCLE GROUP r:y pE~OFS~PLE (ct~ck ooly o~e io this column) ..: . : . . ...... WATER - -.r-] c~lk~ated (R~s~dL~al: To~l-/.':-':"- ~me) ' ~ RIIMI~ · -- . - - - ' ' : - .;-~-~: ' - . .- . ~. -' .' · check~eatme~t:' ' --'~'Fl.l=i~red"-- ' ~" -'."--':: ' :- - :-' -' _ . _.'-' :- : . []Unt~eatedorOt~r'-'~ · . "- - ... '-E]~E~T-~': '.-'.:..-:. '": .... ~:'- · ": :-.-.' ' · '" _ .Previo~co~d~mpmsence Lab# - . ·---- '" .. "'. '.:-: i-i'-.'"'.:- D~ ~..~ '::_...... ~WAT~R -s~l~ E:]-T~.Co~,~ NEW CONSTRUCTION or REPNRS [] Fe<~d C~ifocm '. [] OTHER¢¢~)" ' ~:. ' :- .-_ :. _ _ .-: '(LAeUSEO"L~am~ WATER RESUL~ · . ., 'BI'UNSATISFACTORY': COlif°wns p~esent [] SATISFACTORY; , Cotiforms absent · " '::'REPEAT :' Fl'E.~ipmse~- [] E-¢-,~iab~t~. ~:' ' ' . ..... -' SAMPLES- ' [] FeCal-PreSent [] Fecalabs~nt ' . .'--' ' .REQUIRED . . OT~E~ LAaOR~TOR~ RESULTS . '-TOTAJ. COEtFORM ~-"./100ml'.-. E.cOU ' -./100mi _:-.'-.:'_...-.: . FECALCOUFOR~Z~'~--/¢Om~.. PLATE COUNT "- '..' '/r,b -.. ..... .-- -, · ANOTHER SAMPLEREQURED.' i - ' . ' '"' ' SAMPLE NOTTESTED BECAUsEf · - TEST UNSUITABLE BECAUSE: [] w,~g'~ta~r _ []'TNTC' - .... "[] I~o~p~"~. -.. ' . [] 7u~ur~ '" ." []. . []'E,~,~,b~. ': . SEE REVERSE SIDE OF GREEN COPY FOR EXPLANATION OF RESULTS LAB NO. ~7 DIGITS) : ~ DATE, TIME RECEIVED f D,~RE~ ~ 1(206~78-5285 ;~ -~ J ' 'C~O ~' WATER SUPPLIER COPY RECEIVED BY APPENDIX G Aquifer Test Data Collection Sheet TRI-AREA GROUNDWATER STUDY - AQUIFER TEST WELL START DATE STATIC WATER LEVEL (FEET BELOW MP) DESCRIBE MEASURING POINT PAGE END DATE MEAsuRING SCHEDULE: ELAPSED TIME (min) ' MEASUREMENTS (rain) 0-60 2 60-120 5 120-240 10 240-360 30 360-END 60 TIldE ELAPSED TIME 3EPTH TO WATER DRAWDOWN RECORDER (minutes) (feet) i(feet) INITIALS APPENDIX H Well Hydraulics Equations Well Hydraulics Equations Pumping Phase Data Aquifer test data were analyzed by plotting time versus drawdown on semilog paper. This method employs the Cooper-Jacob modification to the Theis non-equilibrium equation, as follows: 264Q o.3 Tt log ~ T r2S where S= Q = pumping rate, in gpm T = coefficient oftransmissivity of the aquifer, in gpd/f~ S = coefficient of storage (dimensionless) r = distance from the well, in-feet Considering the change in s over one log cycle, As, T can be calculated as follows, 264Q T= As The coefficient of storage can be calculated using the following equation, 0.3 Tto S= r2 drawdown, in feet, at any point in the vicinity of a well discharging at a constant rate where to = the theoretical time obtained by extending the slope of the line back to the zero drawdown axis of the plot A calculation of W(u) for MW-1 shows that the modified non-equilibrium equation is valid for times greater than about 3 minutes. Recovery Phase Data Recovery phase data were analyzed by plotting the ratio fit' versus residual drawdown, s', where, t = time since pumping started (minutes) t' = time since pumping stopped (minutes) s' = residual drawdown (feet), the difference between static water level and the measured water level The resultant plots are then analyzed by finding the slope of the plot, and applying the following equation: 264 Q log t/t' T where parameters are as defined above, Applying the analysis over one log cycle, the equation becomes, 264 Q T = where units are as noted above. -A s~ APPENDIX I Aquifer Test Plots ~ Semi-Lo~arith~c Cycles x 10 to the inch .3 2 . Semi-Logarith~c Cycles x !0 to the inch 3 , .~;emi-Logaritl-~c 4 Cycles x i0 to the inch <3 ~yc!es x 10 to the inch b Semi-Locaritl~ic Cycles x 10 to the inch 3 3 Semi-Logarithmic i~'~yctes x tO to the inch