PORT GAMBLE S’KLALLAM TRIBE ADMINISTRATIVE CAMPUS MASTER PLAN

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Chapter 06

Appendices

PORT GAMBLE S’KLALLAM TRIBE ADMINISTRATIVE CAMPUS MASTER PLAN

CHAPTER 6: APPENDICES

Utilities

Report

PORT GAMBLE S’KLALLAM TRIBE ADMINISTRATIVE CAMPUS MASTER PLAN

CHAPTER 6: APPENDICES

PGST UTILITIES MEMO

A technical memorandum for the utilities

within the administrative campus.

October 11, 2024

Prepared for:

The Port Gamble S'Klallam Tribe

Prepared by:

Zach Barbarick EI,

Jonathan Sweet PE

Ryan Whittle PE

Project Number:

2042681800

PGST Utilities memo

Revision

Description

Author

Date

1.0

Existing utility

conditions

Zach

Barbarick

03/28/2024

2.0

Preliminary

Design

Jonathan

Sweet

07/08/2024

Quality

Check

Project Number: 2042681800

Date

Independent

Review

Date

PGST Utilities memo

The conclusions in this memo are Stantec’s professional opinion, as of the time of the memo, and

concerning the scope described in the memo. The opinions are based on conditions and information

existing at the time the scope of work was conducted and do not take into account any subsequent

changes. This memo relates solely to the specific project for which Stantec was retained and the stated

purpose for which the memo was prepared. It is not to be used or relied on for any variation or extension

of the project, or for any other project or purpose, and any unauthorized use or reliance is at the

recipient’s own risk.

Stantec has assumed that all the information received from The Port Gamble S'Klallam Tribe (the “Client”)

and third parties in the preparation of this memo to be correct. While Stantec has exercised a customary

level of judgment or due diligence in the use of such information, Stantec assumes no responsibility for

the consequences of any error or omission contained therein.

This memo is intended solely for use by the Client in accordance with Stantec’s contract with the Client.

While it may be provided by the Client to applicable authorities having jurisdiction and to other third

parties in connection with the project, Stantec disclaims any legal duty based upon warranty, reliance or

any other theory to any third party, and will not be liable to such third party for any damages or losses of

any kind that may result.

Prepared by:

Signature

Printed Name

Reviewed by:

Signature

Printed Name

Approved by:

Signature

Printed Name

Project Number: 2042681800

PGST Utilities memo

Table of Contents

EXECUTIVE SUMMARY ..................................................................................................5

GENERAL .........................................................................................................................6

Existing Condition .......................................................................................................................................... 6

Demands 6

Utility Corridor ................................................................................................................................................ 6

WATER SYSTEM..............................................................................................................7

Existing Condition .......................................................................................................................................... 7

3.1.1

Supply............................................................................................................................................. 7

3.1.2

Distribution Pressure Zones ........................................................................................................... 7

Demand 8

Recommendations ......................................................................................................................................... 8

3.1.3

Water System Plan......................................................................................................................... 8

3.1.4

Transmission Main ......................................................................................................................... 8

3.1.5

Pressure zones .............................................................................................................................. 8

SANITARY SEWER ....................................................................................................... 10

Existing Conditions ........................................................................................................................................ 9

Demand 5

Recommendations ....................................................................................................................................... 11

4.1.1

Septic Tanks ................................................................................................................................. 11

4.1.2

Grease Traps ............................................................................................................................... 11

4.1.3

Sewer System Plan ...................................................................................................................... 11

STORMWATER MANAGEMENT .................................................................................. 12

Existing Conditions ...................................................................................................................................... 10

5.1.1

Runoff Capture ............................................................................................................................. 12

5.1.2

Conveyance ................................................................................................................................. 12

5.1.3

Treatment ..................................................................................................................................... 12

Demand 1

Recommendations ......................................................................................................................................... 1

5.1.4

Subarea 1 – The Bluff .................................................................................................................... 1

5.1.5

Subarea 2 – Administrative Campus ............................................................................................. 1

5.1.6

Subarea 3 – Baseball field area ..................................................................................................... 1

ELECTRIC POWER ..........................................................................................................2

Existing Conditions ........................................................................................................................................ 1

Demands 5

Recommendations ......................................................................................................................................... 2

GAS ...................................................................................................................................3

Existing Conditions ........................................................................................................................................ 2

Demand 3

Recommendations ......................................................................................................................................... 3

TELECOMMUNICATIONS ...............................................................................................2

Existing Conditions ........................................................................................................................................ 2

Demand 3

Recommendations ......................................................................................................................................... 3

Project Number: 2042681800

PGST Utilities memo

IMPACTED UTILITIES......................................................................................................3

LIST OF TABLES

Table 1 - Avavilable Service ........................................................................................................................ 3

Project Number: 2042681800

PGST Utilities memo

EXECUTIVE SUMMARY

In support of the planned redevelopment of the Port Gamble S’Klallam Tribe (Client) administrative

campus as presented in the 2024 Administrative Campus Master Plan, this memo summarizes the

existing utilities serving Subareas 1-3, discusses utilities that will be impacted by planned redevelopment,

and proposes modifications to the various utility systems present on the campus.

The existing utility information contained in this memo was collected from GIS data provided by the Client,

coordination with their staff, as-built plans, and site observation. Site observation was made both in

person and via Google Street View (images dated August 2018). These limited information sources are

adequate given the planning nature of this memo, but the location and size of existing utilities should be

verified by a licensed Surveyor prior to any future design or construction effort. This memo is intended as

a supplement to Campus Development Utility Analysis (Gray & Osborne, Inc, 2018), with an emphasis on

the geographic region of the administrative campus and utilities that are impacted by the proposed

redevelopment described in the 2024 Master Plan update.

Project Number: 2042681800

PGST Utilities memo

GENERAL

Ownership

The Client owns and operates the water, sanitary sewer, and stormwater management infrastructure

within the Lower Reservation. Electric and communication infrastructure is owned and maintained by third

parties.

Utility Corridor

Establish a utility corridor whose purpose is to consolidate utility development and operation, present and

future, within a narrow zone through the administrative campus. This will disentangle existing utilities in

time, which will help future planning efforts, minimize service disruption, and maximize developable area

elsewhere on the campus. The utility corridor could be roughly under or alongside the existing campus

circulation road that runs from Little Boston Road, south between the police/courts and the proposed

Administration Buildings, then west along the southernmost circulation road past the youth center and

connecting again to Little Boston Road. Reserve future development within this corridor for utilities and

transportation only.

See Appendix B for location of recommended utility corridor.

Project Number: 2042681800

PGST Utilities memo

WATER SYSTEM

Existing Condition

Supply

Two wells actively provide a combined capacity of 288,000 gallons of raw water per day (Gray &

Osborne, Inc, 2018). The active wells are located between the Cultural Resources and Housing/Planning

buildings, and northwest of the Ball Field’s equipment shed. A third emergency/backup well is located

near Gliding Eagle Market; its capacity was not verified and was outside of the scope of this memo.

Raw water from the active wells is conveyed to the Treatment Station located on the North end of the Ball

Field adjacent to Little Boston Road, then to a concrete water reservoir (Main Tank).

A connection from the Kitsap County’s Public Utility District No. 1 (PUD1) water main near Hansville Road

provides pressure and volume during emergency conditions (i.e. low pressure events).

Distribution Pressure Zones

Lower Pressure Zone

The portion of potable water distributed to the PGST community from the main tank under gravity

head and is designated as the Lower Pressure Zone (LPZ). It provides potable water to portions of

the administrative campus, as well as various residential neighborhoods.

Buildings within the administrative campus that are served by the LPZ include the Education Center,

Elder Center, Childhood Education, Cultural Resources, Community Services, and Human

Resources.

Analysis by Gray & Osborne, 2018 determines that the LPZ is not adequate for fire service on

campus.

Upper Pressure Zone

A booster station located north of the campus near Little Boston Road provides additional pressure

for portions of the PGST community at higher elevations known as the Upper Pressure Zone (UPZ).

The UPZ is connected to the LPZ in several other locations via pressure reducing valves (PRV), one

of which is located on campus, southeast of the Administration Building and the Youth Center. The

UPZ provides potable and fire water to portions of the administrative campus, communities east of

and including Cubby Sparks, and the Bud Purser community.

Buildings within the administrative campus that are served by the UPZ include the Administration

Building, Kitchen, Housing/Planning, Library, Health Clinic, Fisheries Wet Lab, and Youth Center.

Analysis by Gray & Osborne, 2018 showed that taking fire flow from the UPZ results in an

unacceptable low pressure in uphill neighborhoods (i.e. S’Klallam Hill), except in the case where the

UPZ is extended by a booster pump provided near the North Reservoir to serve the East

Project Number: 2042681800

PGST Utilities memo

Salmonberries development. GIS indicates that such an improvement has been made to the UPZ, in

which case volume and pressure of the UPZ are expected to adequately service fire flows at the

administrative campus.

See Appendix A – Existing Conditions.

Demand

The new buildings will be sprinklered for fire protection. There will also be increased domestic demand

due to the proposed kitchens, locker rooms, and increased restrooms.

Recommendations

Water System Plan1

Create a water system plan for the Reservation’s water system, as recommended by G&O in 2018.

Having a mathematical model of the entire Reservation’s water system allows the Client to better

understand system-wide impacts resulting from local changes, for example the proposed addition of a

CPZ. A water system plan also enables the Client to discover deficiencies before they manifest, for

example fire flows or emergency conditions, and plan for their resolution before they become a problem.

Transmission Main

It is recommended to convert the existing high pressure main (above 80 psi), currently produced by

pumping to serve the higher elevations of the Upper Reservation, into a transmission main. The

transmission main will distribute water to pressure zones (discussed in detail below) throughout the

Reservation. The transmission main is not suitable for direct domestic or fire service because the

pressure is too high. The transmission main would be routed through Little Boston Road to stay clear of

future Campus redevelopment.

Pressure zones

Campus Pressure Zone (CPZ)

Create a new pressure zone to serve the Campus only. This new Campus Pressure Zone (CPZ) would be

served by the newly created transmission main, with Pressure Reducing Valves (PRV) set to provide

ideal domestic and fire pressures to the Campus, with a service main centrally located within the new

utility corridor, and domestic and fire services to individual campus buildings branching off of this service

1 A detailed evaluation of this intertie’s effectiveness is recommended during the design phase. Interviews

with operations staff revealed that a valve must be manually opened. If this intertie is intended for

emergencies, a more automated solution is recommended. This solution should detect the hydrologic

conditions of the main in real time. See Appendix ? for intertie as-built.

Project Number: 2042681800

PGST Utilities memo

main. Conveyance for the CPZ may utilize existing piping currently serving the UPZ and LPZ onsite

where appropriate.

Lower Pressure Zone (LPZ)

Maintain the pressure zone that currently serves the residential portions of the Lower Reservation south

of the Administrative Campus by connecting to the transmission main via PRVs with set pressure to

provide adequate domestic and residential fire service. The campus will no longer be served by the LPZ.

Upper Pressure Zone (UPZ)

Maintain the pressure zone that currently serves the higher elevation residential neighborhoods. The

campus will no longer be served by the UPZ.

See Appendix B for proposed water layout.

Project Number: 2042681800

PGST Utilities memo

SANITARY SEWER

Existing Condition

Service

Each building on the administrative campus is served by sanitary sewer except for the Longhouse

and the Gym because they do not have bathrooms. Each building served with sanitary sewer has

its own septic tank.

The peak sewer flow rate has been calculated at 3,260 gallons per day for the administrative

campus (Gray & Osborne, Inc, 2018).

Conveyance

Buildings drain via gravity pipe from the buildings, through septic tanks, then by gravity sewer

south along Little Boston Road to a pump station, then by force main to the Wastewater

Treatment Facility at the Upper Reservation.

Treatment

A wastewater treatment plant on the Upper Reservation provides sewage treatment for the

majority of the Reservation and has been assessed in the General Sewer/Wastewater Facility

Plan (Gray & Osborne 2013) to be sufficient in capacity to receive and treat all of the sewage

produced on the Reservation through the 20-yr planning period. As a result, we do not see a

further need to analysis the treatment system.

See Appendix A – Existing Conditions.

Demand

In addition to maintaining sewer service to existing buildings to remain, the proposed Administration

Buildings will also require sewer service.

Recommendations

Septic Tanks

Consolidate the existing septic tank effluent pumping (STEP) infrastructure by removing septic tanks at

individual campus buildings and replace with two tanks serving the north and south portions of campus,

with additional capacity in each tank for future growth. This would allow for reduced maintenance and

reduced cost of future development on the campus. If any building sewers are pumped, this would also

allow for consolidation of pumping infrastructure. The north system would serve the Health Clinic,

Childhood Education, Housing/Planning, Library, Longhouse, Elder Center and Education Center. The

Project Number: 2042681800

PGST Utilities memo

south system would serve the new Administration Buildings, Police/Courts, Children and Family Services,

Cultural Resources Center, Fisheries Lab, and Youth Center.

Grease Traps

Buildings with kitchens will require a dedicated grease trap. The south system will also have a

conveyance main that utilizes the new utility corridor. In the long-term, connections from the north zone

could migrate to the south to further leverage the utility corridor.

Sewer System Plan

Create a system plan for the Reservation’s sanitary sewer system. Having a mathematical model of the

entire Reservation’s sewer system allows the Client to better understand system-wide impacts resulting

from local changes, for example, to verify capacity of conveyance within the campus or downstream lift

station serving much of the Reservation. A sewer system plan also the Client to plan for future demand.

See Appendix B for proposed sewer layout.

Project Number: 2042681800

PGST Utilities memo

STORMWATER MANAGEMENT

Existing Condition

Runoff Capture

Stormwater from the Longhouse roof drains west directly onto a french drain. The four buildings

adjacent to the Longhouse (Library, Housing/Planning, Elder Center, and Education Center) have

drip chains to french drains. All other buildings on campus have conventional roof drains that are

conveyed with underground piping. Parking lots and site roadways mostly drain to catch basins.

Conveyance

Conveyance from the campus ultimately discharges into one of two natural drainage channels

that flow from east to west into Port Gamble Bay. There is a natural channel north of the campus

opposite Little Boston Road, and another is immediately south of the campus.

Roof drains from the Kitchen, Gym and Administration Building daylight to a vegetated swale that

is east of and parallel to Little Boston Road.

Roof drains from the Food Bank/Special Projects Building, Human Resources Building, and

Community Services Building daylight to a vegetated swale that is in the southeast of the

campus.

Roof drains from the Fisheries Wet Lab flows to a dispersion trench located adjacent to the

southern natural channel.

GIS data provided by the Client did not include stormwater conveyance information.

Treatment

Runoff from parking and site roadways south of the Administration Building are treated in

bioretention ponds located in parking islands south of the Administration Building. Another larger

bioretention pond located in the southwest of the site treats runoff from the Administration

Building roof drains and asphalt surfaces west and south of the Administration Building.

See Appendix A – Existing Conditions.

Project Number: 2042681800

PGST Utilities memo

Demand

The new buildings are likely to increase impervious area on the campus, requiring additional stormwater

treatment capacity.

Recommendations

An Urban Stormwater Assessment is being developed concurrently and is expected to be adopted as

early as October 2024. This document will provide various approved measure to promote protection of

the Bluff. Any stormwater improvements within Subareas 1, 2, or 3 should be in alignment with this Urban

Stormwater Assessment.

Subarea 1 – The Bluff

Improvements along Little Boston Road should be intercepted, possibly via bioswale, to prevent erosive

runoff over the bluff.

Subarea 2 – Administrative Campus

Create a new stormwater facility in front of the proposed Administration Buildings along the frontage of

Little Boston Rd to serve new stormwater demands.

Subarea 3 – Baseball field area

The Master Plan proposes that the existing ball field be converted into a gravel overflow parking lot.

Runoff generated from the new gravel lot should generally slope west and intercepted either by area

drains or a conveyance ditch, where it is to be convey to the existing ditch along Little Boston Road ditch,

and eventually on to an existing stormwater pond. Expand the existing pond as necessary to account for

the increase in runoff.

Project Number: 2042681800

A-1

PGST Utilities memo

ELECTRIC POWER + TELECOMMUNICATIONS

Existing Condition

There is a mix of overhead and underground power and telecommunications lines within the

administrative campus.

Campus as-built drawings provided location of lines on parts of the site, supplemented by poles, junction

boxes, meters and building service lines observed using Google Street View.

See Appendix A – Existing Conditions.

Demands

The new Administration Buildings will need electrical power and telecommunications service, but are

anticipated to draw a similar amount of power as the previous Administration Buildings.

The Client has expressed interest in undergrounding of overhead lines on Little Boston Road to achieve a

more scenic view of Port Gamble Bay from the proposed Administration Buildings.

Recommendations

Provide an electrical and telecommunications backbone through the south portion of the new utility

corridor to serve the new Administration Buildings. Other buildings whose electrical or

telecommunications service is disrupted by development of the Administration Buildings can also take

service from these new backbones. Future development should include an extension of this backbone

through the north portion of the utility corridor.

Undergrounding of overhead lines in Little Boston Road would incur a significant cost. It is recommended

that this improvement not be performed at this time, but be reconsidered by the Client after the new

Administration buildings have been occupied for some.

See Appendix B for proposed electrical and telecommunications layout.

Project Number: 2042681800

A-2

PGST Utilities memo

GAS

Existing Condition

No indicators of piped natural gas were observed using Google Street View and no natural gas data was

available by GIS. A 50-lb propane tank was observed west of the Health Clinic and maps from Client staff

indicate that other propane tanks exist on the Campus, further suggesting that no piped natural gas is

available.

Demand

The new buildings include multiple kitchens and will therefore need gas supply.

Recommendations

Provide propane tank service to proposed kitchens, consistent with current gas services on the campus.

Future development of gas infrastructure should utilize the new utility corridor.

Project Number: 2042681800

A-3

EXISTING LEGEND

CAMPUS BOUNDARY

WATER METER

EXISTING BUILDING

POST INDICATOR VALVE

UNDERGROUND ELECTRICAL

WATER VALVE

OVERHEAD ELECTRICAL

PRESSURE REDUCING VAULT

TELECOMMUNICATIONS

SEWER CLEANOUT

SEWER FORCEMAIN

TELECOM BOX

GRAVITY SEWER

FIRE DEPARTMENT CONNECTION

STORM POND

STREET LIGHT

UPPER ZONE WATER LINE

SANITARY SEWER MANHOLE

LOWER ZONE WATER LINE

SEPTIC TANK

WELL SUPPLY LINE

PAD MOUNTED TRANSFORMER

WELL

STORM POND

FIRE HYDRANT

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Bellevue, Washington 98004

Tel:425-289-7333

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EXISTING LEGEND

CAMPUS BOUNDARY

EXISTING BUILDING

UPPER ZONE WATER LINE

LOWER ZONE WATER LINE

WELL SUPPLY LINE

WELL

FIRE HYDRANT

WATER METER

POST INDICATOR VALVE

WATER VALVE

PRESSURE REDUCING VAULT

FIRE DEPARTMENT CONNECTION

SERVED BY UPPER ZONE WATER LINE

SERVED BY LOWER ZONE WATER LINE

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EXISTING LEGEND

CAMPUS BOUNDARY

EXISTING BUILDING

SEWER FORCEMAIN

GRAVITY SEWER

SEWER CLEANOUT

SANITARY SEWER MANHOLE

SEPTIC TANK

STORM POND

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Tel:425-289-7333

www.stantec.com

EXISTING LEGEND

CAMPUS BOUNDARY

EXISTING BUILDING

UNDERGROUND ELECTRICAL

OVERHEAD ELECTRICAL

TELECOMMUNICATIONS

TELECOM BOX

STREET LIGHT

PAD MOUNTED TRANSFORMER

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PRV

TRANSMISSION

- CONTINUE EXISTING UPZ THROUGH

LITTLE BOSTON ROAD.

-TRANSMISSION SERVES LPZ AND CPZ

(SHOWN) AND UPZ (NOT SHOWN).

BOOSTER PUMP

TEEL

CAMPUS PRESSURE ZONE (CPZ)

- REPURPOSE EXISTING UPZ AND LPZ PIPING ON CAMPUS.

- CONNECT TO UPZ IN TWO PLACES VIA PRV.

- SET PRV PRESSURES TO ADEQUATELY SERVE CAMPUS'

DOMESTIC AND FIRE SERVICE DEMANDS WITHIN A SINGLE

PRESSURE ZONE.

TEL

PROPOSED LEGEND

EXISTING LEGEND

TEL

CAMPUS BOUNDARY

EXISTING BUILDING

ELECTRICAL LINE

TELECOMMUNICATION LINE

XFM

SEWER FORCEMAIN

XSS

GRAVITY SEWER

TEL

STORM POND

WATER LINE - ADMIN PRESSURE ZONE

TEEL

FIRE HYDRANT

TEEL

WATER LINE - WELL SUPPLY

WELL

WATER METER

POST INDICATOR VALVE

WATER VALVE

TEE

PRV

TELE

WATER LINE - LOW PRESSURE ZONE

PRV

WATER LINE - HIGH PRESSURE ZONE

PRV

PRESSURE REDUCING VAULT

SCO

SEWER CLEANOUT

TELE

TELECOM BOX

PRV

FIRE DEPARTMENT CONNECTION

STREET LIGHT

SANITARY SEWER MANHOLE

SEPTIC TANK

LOWER PRESSURE ZONE (LPZ)

-CONNECT TO UPZ VIA PRV TO MAINTAIN

SERVICE TO LITTLE BOSTON COMMUNITY.

- LPZ NO LONGER SERVES CAMPUS.

TEEL

TFMR

PAD MOUNTED TRANSFORMER

UTILITY CORRIDOR

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PRV

TEEL

TEL

CONSOLIDATED STEP SYSTEM - NORTH ZONE

- REMOVE SEPTIC TANKS AT INDIVIDUAL BUILDINGS.

- INSTALL SINGLE SEPTIC TANK OVER EXISTING LINE.

- PROVIDE ADDITIONAL CAPACITY FOR FUTURE GROWTH.

PROPOSED LEGEND

EXISTING LEGEND

TEL

CAMPUS BOUNDARY

EXISTING BUILDING

ELECTRICAL LINE

TELECOMMUNICATION LINE

XFM

SEWER FORCEMAIN

XSS

GRAVITY SEWER

TEL

WATER LINE - LOW PRESSURE ZONE

WATER LINE - ADMIN PRESSURE ZONE

WATER LINE - WELL SUPPLY

FIRE HYDRANT

TEEL

WELL

WATER METER

POST INDICATOR VALVE

WATER VALVE

TEE

PRV

TELE

PRV

WATER LINE - HIGH PRESSURE ZONE

STORMWATER MANAGEMENT

- INSTALL BIORETENTION PONDS ALONG

LITTLE BOSTON ROAD FRONTAGE.

TEEL

STORM POND

PRV

PRESSURE REDUCING VAULT

SCO

SEWER CLEANOUT

TELE

TELECOM BOX

PRV

FIRE DEPARTMENT CONNECTION

STREET LIGHT

SANITARY SEWER MANHOLE

SEPTIC TANK

CONSOLIDATED STEP SYSTEM - SOUTH ZONE

- REMOVE SEPTIC TANKS AT INDIVIDUAL BUILDINGS.

- LAY SEWER MAIN WITHIN UTILITY CORRIDOR.

- INSTALL SINGLE SEPTIC TANK.

- PROVIDE ADDITIONAL CAPACITY FOR FUTURE GROWTH.

TFMR

PAD MOUNTED TRANSFORMER

UTILITY CORRIDOR

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PRV

TEEL

TEL

EXISTING LEGEND

TEL

PROPOSED LEGEND

CAMPUS BOUNDARY

EXISTING BUILDING

ELECTRICAL LINE

TELECOMMUNICATION LINE

XFM

SEWER FORCEMAIN

XSS

GRAVITY SEWER

TEL

STORM POND

TEEL

WATER LINE - LOW PRESSURE ZONE

WATER LINE - ADMIN PRESSURE ZONE

WATER LINE - WELL SUPPLY

WELL

TEEL

FIRE HYDRANT

WATER METER

POST INDICATOR VALVE

TEE

WATER VALVE

PRV

PRESSURE REDUCING VAULT

SCO

SEWER CLEANOUT

TELE

TELECOM BOX

PRV

FIRE DEPARTMENT CONNECTION

STREET LIGHT

SANITARY SEWER MANHOLE

PRV

TELE

TEEL

WATER LINE - HIGH PRESSURE ZONE

PRV

TEEL

SEPTIC TANK

TFMR

PAD MOUNTED TRANSFORMER

UTILITY CORRIDOR

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Soil and

Geotechnical

Report

PORT GAMBLE S’KLALLAM TRIBE ADMINISTRATIVE CAMPUS MASTER PLAN

CHAPTER 6: APPENDICES

Preliminary Geotechnical Study

Port Gamble S’Klallam Tribe – Administrative

Campus Master Plan

Kingston, Washington

for

Port Gamble S’Klallam Tribe

May 15, 2024

1101 South Fawcett Avenue, Suite 200

Tacoma, Washington 98402

253.383.4940

Preliminary Geotechnical Study

Port Gamble S’Klallam Tribe – Administrative

Campus Master Plan

Kingston, Washington

File No. 0181-010-00

May 15, 2024

Prepared for:

Port Gamble S’Klallam Tribe

c/o Stantec Consulting Services, Inc.

720 Third Avenue, Suite 1500

Seattle, Washington 98104

Attention: Ryan Whittle

Prepared by:

GeoEngineers, Inc.

1101 South Fawcett Avenue, Suite 200

Tacoma, Washington 98402

253.383.4940

Christopher R. Newton, PE

Senior Geotechnical Engineer

Dennis (D.J.) Thompson, PE

Associate Geotechnical Engineer

CRN:DJT:atk

Disclaimer: Any electronic form, facsimile, or hard copy of the original document (email, text, table, and/or figure), if provided, and any attachments are only a copy

of the original document. The original document is stored by GeoEngineers, Inc. and will serve as the official document of record.

Port Gamble S’Klallam Tribe c/o Stantec Consulting Services, Inc. | May 15, 2024

Table of Contents

1.0 Introduction and Project Description .............................................................................. 1

2.0 Scope Of Services ......................................................................................................... 1

3.0 Site Conditions ............................................................................................................. 1

3.1 Site Limits and Vicinity.................................................................................................................. 1

3.2 Literature Review .......................................................................................................................... 2

3.2.1

Geologic Mapping .............................................................................................................. 2

3.2.2

Natural Resources Conservation Service Description .................................................... 3

3.2.3

Critical Areas: Geologic Hazards....................................................................................... 4

4.0 Geotechnical Engineering Evaluation ............................................................................. 5

4.1 General .......................................................................................................................................... 5

4.2 Anticipated Soil and Groundwater Conditions ............................................................................ 6

4.3 Seismic Site Class ......................................................................................................................... 6

4.4 Foundation Support ...................................................................................................................... 6

4.5 Retaining Walls and Below-Grade Structures ............................................................................. 7

4.5.1

General............................................................................................................................... 7

4.5.2

Gravity Walls ...................................................................................................................... 8

4.5.3

Shoring and Other Walls ................................................................................................... 8

4.5.4

Preliminary Design ............................................................................................................ 9

4.6 Infiltration Feasibility Assessment ............................................................................................... 9

4.7 Earthwork Considerations ............................................................................................................ 9

4.7.1

Stripping, Clearing, and Subgrade Preparation ............................................................... 9

4.7.2

Wet Weather Considerations .......................................................................................... 10

4.7.3

Cut and Fill Slopes........................................................................................................... 10

4.7.4

Groundwater Handling .................................................................................................... 10

4.7.5

Fill Materials and Compaction ........................................................................................ 11

5.0 Recommendations for Further Studies ......................................................................... 12

6.0 Limitations.................................................................................................................. 13

7.0 References.................................................................................................................. 13

List of Figures

Figure 1. Vicinity Map

Figure 2. Site Plan

Figure 3. Lidar Map

Figure 4. Geologic Map

Figure 5. Soil Survey Map

Figure 6. Seismic Hazards Map

Appendices

Appendix A. Report Limitations and Guidelines for Use

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1.0 Introduction and Project Description

GeoEngineers, Inc. (GeoEngineers) is pleased to present this preliminary geotechnical study for the

Port Gamble S’Klallam Tribe - Administrative Campus Master Plan project. The project site is located at

31912 Little Boston Road NE (Tribal Headquarters) in Kingston, Washington, as shown in the Vicinity Map,

Figure 1.

Our understanding of the project is based on discussions with you and review of Stantec’s Preliminary Base

Maps dated February 2024. We also reviewed the “AS BUILTS, ADMINISTRATION CAMPUS PROJECT: CIVIL

DRAWINGS, PORT GAMBLE INDIAN RESERVATION” dated November 7, 2011, prepared by U.S. Department

of the Interior, Bureau of Indian Affairs.

The overall project consists of developing a master plan for design and construction of a new multi-story

Administration Building with below-grade parking and associated improvements. The proposed

development areas are shown as Subareas 1 through 3 in the Site Plan, Figure 2. The new Administration

Building is planned to be constructed in Subarea 1. The master planning process will include a review and

analysis of the existing site, public engagement to gather input and feedback to proposed master plan

concepts, cost estimates on the preferred and final master plans, and associated phasing and funding

strategies. We envision geotechnical-related project elements could include shallow foundations and

below-grade building wall design, temporary cut slopes and/or shoring, site grading, new pavement areas,

stormwater facilities, and underground utility installation.

2.0 Scope Of Services

For our study, we reviewed existing information in the project vicinity to develop an understanding of surface

and subsurface conditions in the area. Based on this information, we have prepared this report providing

our preliminary opinion on the suitability of the considered Subareas 1 through 3 for future development

with regards to geotechnical considerations. The results of our services are intended to support decisions

regarding site selection, preliminary project engineering, and future planning. This is a preliminary

geotechnical study and is not intended to support final design of site improvements. Additional geotechnical

services, including site specific explorations and other engineering design and analysis will be required to

support final design for future development.

Our services have been provided in accordance with our signed agreement with Stantec dated

January 5, 2024.

3.0 Site Conditions

3.1

SITE LIMITS AND VICINITY

The Tribal Headquarters Campus (Campus) is occupied by several buildings for administration and

education and includes a gymnasium, a library, health clinics, police, court, and other services. A ball field

is located near the northeast corner of the Campus. Other site features include landscaping, asphalt

pavements, sidewalks, and drainage features such as swales and ditches.

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The proposed development areas are shown as Subareas 1 through 3 in the Site Plan, Figure 2. Subarea 1

is in the southwest quadrant of the site and currently includes the existing Administration Building, Natural

Resources, gymnasium, kitchen, playground, and parking. Subarea 2 is toward the west of the Campus,

and contains a few vacant homes, a tribal arts center, and cemetery. Subarea 3 is in the north-central

portion of the Campus on the northwest edge of the ball field, adjacent to a parking lot driveway and Little

Boston Road NE.

The project site is bordered to the north by Little Boston Road NE and forested area to the east and south.

Little Boston Road NE also intersects the site on the western half between the Campus and Subarea 2 A

bluff separates the upland Subarea 2 from Port Gamble Bay to the west. Overall, project site topography is

generally flat, as shown by the lighter shading in the Lidar Map, Figure 3. Other topographic features at or

near the site shown on the Lidar Map include a stream or creek channel ravine to the north of site, a stream

or creek channel running through the southeast corner of the site, and a shallow ravine on the southwest

corner of the site.

3.2

LITERATURE REVIEW

3.2.1 Geologic Mapping

We reviewed the Washington State Department of Natural Resources (DNR) Geologic Information Portal to

develop an understanding of site geology using the 1:100,000-scale (100k) surface mapping. The mapping

reports glacial soils underlie the site and surrounding areas. Soils present below glacial ice are glacially

overridden (glacially consolidated) and typically dense to very dense; these soils are generally characterized

by relatively high strength, high allowable bearing pressures, and low compressibility. Examples of glacially

consolidated soils include glacial till, advance glacial outwash, and glacial drift. Soils deposited after glacial

recession were not glacially overridden and, in general, are relatively less dense. Examples of post-glacial

soils include alluvium (river and stream deposits) and recessional glacial outwash.

Per the DNR Geologic Information Portal, four geologic units are mapped at or adjacent to the site, and are

shown on the Geologic Map, Figure 4:

■ Continental Glacial Outwash, Fraser-age (Qgo): Mapped along the northwest half of the site and

contains most of Subareas 2 and 3. Glacial outwash typically consists of a mixture of sand and gravel

in a loose to dense condition and can include localized coarser- or finer-grained constituents. Glacial

outwash is deposited from meltwater from a receding glacier and commonly overlies glacial till and is

not glacially consolidated. Cobbles and boulders can be present within glacial outwash deposits. In this

report we refer to material mapped as Continental glacial outwash as “recessional outwash.”

■ Continental Glacial Till, Fraser-age (Qgt): Mapped over the southeast half of the site and contains

most of Subarea 1. Glacial till typically consists of a compact mixture of clay, silt, sand, and gravel.

Cobbles and boulders can be present within glacial till deposits. It is not uncommon for the upper few

feet of glacial till to be weathered and relatively less dense.

■ Continental Glacial Drift, pre-Fraser (Qgp): Mapped at and adjacent to the southwest corner of the

site. In the region, pre-Fraser glacial drift typically consists of clay, silt, sand, and gravel that is in a

medium dense to very dense condition.

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■ Advance Continental Glacial Outwash, Fraser-age (Qga[t]): Mapped at and adjacent to the southeast

corner of the site. Advance glacial outwash (advance outwash) typically consists of sand and gravel

that is deposited by meltwater in front of an advancing glacier and then overridden by the glacier and

is generally observed to be in a dense to very dense condition. Advance outwash commonly underlies

glacial till, and a gradual transition in material gradation may be present upward into the overlying

glacial till. Cobbles and boulders can be present within advance outwash deposits.

Although not mapped, we anticipate fill placed during previous site development activities (i.e., establishing

building pad elevations and grading for parking lot and driveway surfaces) are present at the site.

3.2.1.1

WATER WELL INFORMATION

We searched the DNR Geologic Information Portal for water well log reports in the project vicinity. Our

search identified two water well log reports located at residential properties about 1 to 1.1 miles north of

the project site. Reported subsurface information from the reviewed water well log reports are shown in

Table 1 below.

TABLE 1. SUBSURFACE INFORMATION FROM WELL LOGS

REPORTED DEPTH TO STATIC GROUNDWATER

(DATE OF MEASUREMENT)

WELL LOCATION

WELL DEPTH

REPORTED SOIL CONDITIONS

33700 Hood

Canal Drive NE

88 feet

57 feet

(09/23/92)

“Till” and sand and gravel

33787 Hood

Canal Drive NE

161 feet

80 feet

(03/18/93)

“Hard pan,” sand and gravel, clay

Soils reported in the reviewed well log reports appear to predominantly consist of glacial deposits. Based

on review of Google Earth, the ground surface elevations between the above two properties appear to differ

by at least 30 feet, with the 33787-property shown to be lower in elevation. We interpret static groundwater

levels reported in the reviewed well log reports to be representative of a deeper regional groundwater

table(s) in the project vicinity. Due to the ground surface elevation difference between the above properties

and where static groundwater levels are reported in each well, it is possible that they are two different

aquifers, with the well installed at the 33787-property targeting a deeper aquifer than the well at the

33700-property. Shallower perched groundwater could also be present in the project vicinity, as described

in the “Anticipated Soil and Groundwater Conditions” section of this report.

3.2.2 Natural Resources Conservation Service Description

According to the Natural Resources Conservation Service (NRCS) Web Soil Survey, the project site is

underlain by the three soil types shown on the Soil Survey Map, Figure 5: Indianola-Kitsap complex, 45 to

70 percent slopes (Map Unit 21), Kitsap silt loam, 2 to 8 percent slopes (Map Unit 28), and Ragnar fine

sandy loam, 0 to 6 percent slopes (Map Unit 44). The parent materials of these soils mapped at the site

are primarily derived from glacial deposits, which is generally consistent with the above geologic mapping.

Additional information pertaining to each mapped soil type is presented in Table 2 below.

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TABLE 2. NRCS MAPPED SOIL TYPES

EROSION HAZARD

RATING

SOIL TYPE

Indianola-Kitsap

complex

Severe

HYDROLOGIC

SOIL GROUP

PARENT MATERIAL

Indianola: Glacial outwash

Indianola: A

Kitsap: Lacustrine deposits with

volcanic ash in the upper part

Kitsap: C

COMMENTS

Indianola: Described as

“somewhat excessively

drained” with a “high”

capacity of the most limiting

layer to transmit water.

Kitsap: Described as

“moderately well drained”

with a “moderately low to

moderately high” capacity of

the most limiting layer to

transmit water.

Kitsap silt loam

Moderate

Lacustrine deposits with

volcanic ash in the upper part

Described as “moderately

well drained” with a

“moderately low to

moderately high” capacity of

the most limiting layer to

transmit water.

Ragnar fine

sandy loam

Slight

Glacial outwash with some

volcanic ash in the upper part

Described as “well drained”

with a “high” capacity of the

most limiting layer to transmit

water.

3.2.3 Critical Areas: Geologic Hazards

Per the Kitsap County Critical Areas Map, most of Subarea 2 along the western bluff side is mapped as a

“high” geologically hazardous area, which is categorized for areas of high erosion hazard, and/or landslide

hazard, and/or seismic hazard. We also reviewed the Kitsap County Geologically Hazardous Maps related

to landslide, erosion, and seismic hazards. A general discussion of these geologic hazards is provided in

the sections below and should be reviewed in coordination with other jurisdictional requirements, as project

design progresses.

3.2.3.1

LANDSLIDE HAZARDS

Per the Kitsap County Landslide Hazards Map, Subarea 2 along the western bluff side is mapped as

“moderate” for shallow and deep landslides. The Kitsap County Critical Areas Map defines “moderate”

landslide hazards as:

■ Shallow landslides with factors of safety (FS) of 1.5 to 2.5; and/or

■ “Slopes of 15 percent or greater and not classified as I, U, UOS, or URS (intermediate, unstable,

unstable old slide, or unstable recent slide as defined by the Coastal Zone Atlas), with soils classified

by the U.S. Department of Agriculture NRCS as ‘highly erodible’ or ‘potentially highly erodible; or slopes

of 15 percent or greater with springs or groundwater seepage;” and/or;

■ Slopes in all areas equal to or greater than 40 percent (2.5H:1V [horizontal to vertical]).

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According to the DNR Geologic Information Portal, no known landslides or landslide hazard areas are

mapped at the site. The Coastal Zone Atlas (presented on the Washington State Department of Ecology’s

online Coastal Atlas Map) appears to have eliminated this site area from their mapping.

3.2.3.2

EROSION HAZARDS

Per the Kitsap County Erosion Hazards Map, most of Subarea 2 along the western bluff side is mapped as

“high” for coastal erosion and the channel migration zone. The Kitsap County Critical Areas Map defines

high erosion hazards as:

■ Areas with coastal erosion having a “sediment source rating value of 0.6 to 1.0;” and/or

■ Channel migration zones that are mapped by the Washington State Department of Ecology.

The Kitsap County Erosion Hazards Map is generally consistent with the NRCS “severe” erosion hazard

rating defined in Table 2 above for the Indianola-Kitsap complex soil unit, which occupies most of

Subarea 2.

3.2.3.3

SEISMIC HAZARDS

Per the Kitsap County Seismic Hazards Map, no seismic hazards were mapped at the site. According to the

DNR Geological Information Portal, the approximate northwest half of the site is mapped as “low” potential

for liquefaction, while the approximate southeast half is mapped as “very low.” Further, the nearest mapped

fault or other seismogenic feature is more than 1 mile away from the site. For reference, a portion of the

seismic hazards map from the DNR Geological Information Portal is reproduced in this report as Figure 6.

Based on the reviewed seismic mapping, our understanding of site geology, and anticipated soil conditions,

it is our opinion the site has low potential for liquefaction and seismic surface rupture caused by faults and

other seismogenic features. Based on our assessment of the potential for soil liquefaction and current site

topography, in our opinion this site also has a low potential for lateral spreading.

4.0 Geotechnical Engineering Evaluation

4.1

GENERAL

Based on our review of soil and geologic information described above, it is our opinion that the project site

is generally suitable for development with regards to geotechnical considerations. However, for

development at Subarea 2, we recommend additional critical area studies be conducted and reviewed in

regard to infrastructure location since most of this area is identified by Kitsap County as a geologic hazard

related to landslides and erosion, as described above. As such, we envision that development at Subarea 2

will be more limited, depending on the results of a geologic critical area study, and likely will be constrained

by slope setback buffers and special erosion protection measures. We anticipate potential erosion hazards

can be mitigated through engineering controls such as limiting ground disturbance, site grading, planting,

and other erosion control measures.

We did not identify geotechnical related conditions that would prohibit or significantly constrain overall

project design and construction at Subareas 1 and 3. Regardless, the project layout and design will need

to incorporate geotechnical considerations as discussed herein. In our opinion, these geotechnical

considerations can be managed through appropriate site layout, engineering design, and construction

methods.

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Preliminary recommendations provided in the sections below are intended to support initial design

development, preliminary engineering, cost estimating, and future site planning. These recommendations

are not intended to support final project design. Ultimately, we recommend site and project specific

geotechnical explorations and analysis be completed as a part of final design of future improvements. Refer

to the “Recommendations for Further Studies” section below for discussion and considerations on further

geotechnical studies at the site.

4.2

ANTICIPATED SOIL AND GROUNDWATER CONDITIONS

Soil conditions at the site are expected to consist of a variable thickness of topsoil and fill underlain by

glacial soils. Fill thickness is expected to be greatest in areas of past development or areas where prior

grading activities were completed. Topsoil (and forest duff) thicknesses are expected to be greatest in

undeveloped forested areas (east and south edges of the site). Based on overall topography and

surrounding site grade, we expect that, with the exception of isolated areas, topsoil and fill units will likely

be less than a few feet thick at this site.

Underlying the topsoil and fill, and as described above, we anticipate the northwest half of site (Subareas 2

and 3) to consist of recessional outwash (Qgo) and the southeast half (Subarea 1) glacial till (Qgt). The

recessional outwash will likely consist of medium dense sand and gravel with variable silt and cobble

content. The glacial till will likely consist of dense to very dense silty sand with variable gravel and cobble

content. Boulders could be present within these glacial soils at the site. We also anticipate that the upper

few feet of the glacial soils could be weathered and relatively less dense than underlying intact soils.

Based on our understanding of site geology, it is our opinion that the groundwater well data described

above is not enough information to infer groundwater depths at the project site. Typically, in upland areas

of glacial deposits like this project site, we observe static groundwater deeper than 10 feet, and we envision

groundwater to be near the same elevation as the nearby creeks described previously. However, perched

groundwater could be encountered at relatively shallow depths across the site. Perched groundwater is

typically due to infiltration of surface water that slows or terminates atop underlying less permeable layers

of soil (e.g., on top of glacial till deposits). The presence of fill, discontinuities, utilities, and other factors

also influence the presence and volume of perched water.

4.3

SEISMIC SITE CLASS

We assume improvements will be designed in accordance with the International Building Code (IBC). The

2021 edition of the IBC state structures shall resist the effects of earthquake motions in accordance with

American Society of Civil Engineers (ASCE) 7-16 “Minimum Design Loads and Associated Criteria for

Buildings and Other Structures.” In accordance with IBC 2021 and ASCE 7-16, we recommend a seismic

Site Class D be considered for preliminary, simplified code-based seismic design and analysis. As planning

and design progresses, site exploration and testing should be completed to confirm the seismic Site Class.

Based on project location, there is a possibility that Site Class C may be appropriate with additional

explorations and studies.

4.4

FOUNDATION SUPPORT

We envision that structures at this site can be adequately supported on shallow foundations and slab-ongrade floors bearing on existing site soils. Shallow foundations should be established at least 18 inches

below the lowest adjacent grade, primarily for frost protection. Interior column footings can be founded a

minimum of 12 inches below the bottom of the interior floor slabs. Isolated spread footings should have a

minimum width of 24 inches. Continuous spread footings for walls should be at least 18 inches wide.

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The presence of fill should be evaluated during any final studies to determine if the fill is suitable for bearing

support. Re-compaction and/or removal and replacement of existing fill beneath foundations may be

required depending on the condition, amount of organic and/or deleterious material, and overall matrix.

Ultimately, foundation bearing support recommendations will depend on soil type, structure loads,

foundation elevations, and performance requirements and should be incorporated as part of future

geotechnical studies.

Topsoil, or soils with a high organic content, will need to be completely removed from below foundations

and foundation elements. For preliminary design, we estimate allowable soil bearing resistance of near

surface soils (including existing fill and weathered glacial soils) will be on the order of 2,000 to

3,000 pounds per square foot (psf). Higher bearing resistances (3,000 to 6,000 psf) will likely be

achievable if foundations are supported directly on undisturbed glacially consolidated soils (i.e., glacial till

or advance outwash) at depth. For preliminary planning, increasing these values by about one third may be

considered for transient or infrequent extreme loading conditions, such as forces induced by earthquakes.

For the bearing conditions and resistances presented above, we anticipate that total and differential

foundation settlements can be limited to 1 and ½ inch, respectively, for typical foundation sizes and

structures considered.

Lateral resistance for building design is typically accommodated from backfill around foundation elements

and as friction developed on the bottom of foundations. For published soil types and structural fills

anticipated for this site, we suggest a preliminary value of 300 pounds per cubic foot (pcf) as a passive

resistance for native materials or structural fill against embedded elements. A coefficient of friction for

concrete against anticipated soil materials can be assumed to be around 0.40. These values include a

factor of safety of about 1.5.

Slab-on-grade floors can likely be adequately supported on existing fill and/or underlying glacial soils.

Subgrades for slab-on-grade floors should be compacted to a uniformly firm and unyielding condition. For

preliminary design, floor slab loads should be limited to 300 psf. Typical in-place subgrade modulus values

on the order of 200 to 300 pounds per cubic inch (pci) are common in glacial deposits. For mat foundations

or larger footings, modifications to this value may be required depending on the specific foundation sizes

used in design.

4.5

RETAINING WALLS AND BELOW-GRADE STRUCTURES

4.5.1 General

We anticipate retaining walls may be required to maintain desired site grades and construct below-grade

elements (i.e., basement parking for the new Administration Building). The specific retaining wall type used

will depend in part on the application and wall height. For this site, we expect that modular block walls,

cast-in-place walls, structural earth walls, soil nail walls, and soldier piles walls are all feasible for use.

Additional excavation to develop stable temporary slopes behind retaining walls are commonly required for

worker safety and for construction access and should also be considered in overall planning. Sites with

limited area for back slope excavations may require a different type of shoring or retaining wall system.

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4.5.2 Gravity Walls

Cast-in-place walls may be considered in either cut or fill applications and are typically most efficient for

intermediate wall heights that are taller than about 5 feet but less than about 10 feet. Typically, foundation

base widths of at least half the height of the wall are required for weight and overall stability. This width

can be modified by the use of keyways and other foundation geometry options as determined by a structural

engineer.

Modular block walls typically consist of larger blocks of concrete stacked in a staggered pattern on-top of

each other. Examples include “ecology block” walls and other segmental-type block walls (i.e., Redi-Rock,

Hilfiker, SierraScape, Ultra Block, etc.). Modular block walls are typically most effective for relatively short

walls (less than about 6 feet tall) and can be used in cut and fill grading applications. Modular block walls

taller than about 6 feet will require additional considerations including revised base width design and

additional batter (angle away from vertical).

Structural earth walls are also a type of modular block wall but typically encompass smaller or different

blocks (Keystone, Redi-Rock, Mesa, SierraScape, etc.) as facing and include reinforcing grid or “geo-grid”

installed behind the facing. Typical vertical spacing between the grid is about 18 to 24 inches. Grid lengths

are typically about 70 to 90 percent of the wall height and decrease in overall lengths near the bottom of

the wall. Structural earth walls are best suited for use in fill applications and can be designed to retain

grade differentials greater than 20 feet.

4.5.3 Shoring and Other Walls

Soil nail and soldier pile walls are best suited for cut wall applications and are most often used to retain or

reinforce tall slopes or as temporary shoring to construct below-grade building elements. These wall types

are commonly used where site constraints do not allow for temporary cut slopes, where the excavation

needs to be limited to the building or work area, where movement of nearby structures and/or utilities

needs to be limited or applies a surcharge loading. Both wall types are constructed as the excavation is

advanced, i.e., “top-down construction”. The use of tiebacks for soldier pile walls, or “nails” for soil nail

walls requires horizontal space or soil area behind the wall. The tiebacks or nails may encroach upon

rights-of-way or into other structures. This should be a consideration as a part of determining wall type.

Soldier pile walls are constructed with vertical steel “H” piles installed in a drilled hole (typically 24 to

36 inches in diameter) and filled with lean-mix or structural concrete. The piles are typically spaced 5 to

10 feet apart. The space between piles is typically spanned with wood lagging, shotcrete, or pre-cast

concrete panels. Depending on loading conditions, depth of excavation, and other conditions, tie-back

anchors that are connected to the H piles can be installed for additional lateral support. Typically, soldier

pile walls taller than about 15 feet are more economical to build with the use of tie- back anchors.

Soil nail walls are constructed in lifts by first excavating about 3-to-5-feet and drilling near horizontal 6- to

8-inch diameter holes and installing a steel threadbar nail into the hole. This is done throughout the wall

spacing, typically 6 to 10 feet on-center but with each row staggered. Each lift is completed by placing steel

reinforcing over the cut face and nails, followed by shotcrete facing, and a bearing face plate and nut at

the exposed end of the soil nail. Each 3-to-5-foot lift is finalized before excavating another lift. For some soil

types that are more prone to raveling and caving, vertical elements are drilled and installed before

excavation to help support the cut face while the soil nail wall is constructed.

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4.5.4 Preliminary Design

For preliminary planning purposes, we recommend evaluating walls using an active equivalent fluid density

of 35 pounds per cubic foot (pcf) (triangular distribution). This assumes that the walls will not be restrained

against rotation when backfill is placed and the backfill behind the wall is level. For walls restrained from

rotation at the top (i.e., at-rest condition), an equivalent fluid density of 55 pcf (triangular distribution) can

be used. These values assume drained conditions behind the wall (i.e., do not account for the effects of

hydrostatic conditions). For sloping backfill conditions up to 2H:1V, this value should be increased by about

50 percent.

Lateral resistance of retaining walls can be evaluated assuming a passive equivalent fluid density of

300 pcf and an allowable frictional resistance of 0.4 (these values include a factor of safety of about 1.5).

These values must be confirmed as part of the final design.

Retaining walls should be designed with a drainage system to prevent the buildup of hydrostatic pressures

behind the wall. This is typically accomplished with a zone of free draining material placed behind the wall,

on the order of 18 inches in thickness, for nearly the full height of the wall. The drainage material should

be connected to a perforated rigid piping placed near the bottom of the wall and sloped to drain to an

appropriate discharge. “Waffle” drain mats can also be considered provided they are protected from the

backfill soil and connect to a drain.

4.6

INFILTRATION FEASIBILITY ASSESSMENT

Stormwater infiltration into the recessional outwash soils as mapped on the northwest half of the site is

anticipated to be feasible but will depend on depth to groundwater and underlying impeding layers

(i.e., glacial till). The glacial till mapped on the southeast half of the site is anticipated to have a relatively

high fines content and have a very low infiltration potential. We envision some infiltration is possible into

near-surface fill or weathered glacial till deposits; however, overall rates will likely be reduced due to soil

layering and shallow depth to intact glacial till. Based on our experience in similar soil conditions, we

recommend intact glacial till soils be considered relatively impermeable for preliminary planning.

Accordingly, new stormwater systems on the southeast half of the site will likely need to consider some

form of detention.

4.7

EARTHWORK CONSIDERATIONS

4.7.1 Stripping, Clearing, and Subgrade Preparation

Existing surfaces within proposed development areas should be cleared and stripped of all vegetation and

organics prior to site development. In areas containing trees and shrubs, we expect that stripping depths

could exceed 6 inches. In existing landscape areas, stripping depths could be around 2 to 4 inches.

Subgrades that will support structural elements and pavements should be thoroughly compacted to a

uniformly firm and unyielding condition on completion of stripping/excavation and before placing structural

fill. If soft or otherwise unsuitable subgrade areas are observed and cannot be compacted to a stable and

uniformly firm condition, we recommend that: (1) the unsuitable soils be scarified (e.g., with a ripper or

farmer’s disc), aerated and recompacted, if practical; or (2) the unsuitable soils be removed and replaced

with compacted structural fill, as needed.

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Existing structural improvements (e.g., pavements, hardscaping, and foundations) within proposed

development areas should be demolished and removed prior to redeveloping the site. Recycling or

incorporating old foundation or pavement elements into fill areas can be considered but must be evaluated

on a case-by-case basis. All existing utilities within the new building footprint(s) should be re-routed and/or

removed, as needed. If necessary, abandoned utilities may be left in place if properly filled with a controlled

density, cementitious fill.

4.7.2 Wet Weather Considerations

We expect that the majority of the soils at the site will contain a significant percentage of fines (materials

smaller than the No. 200 U.S. sieve) and will be sensitive to small changes in moisture content. If these

moisture sensitive soils become wet, they will be very difficult or impossible to work with and be highly

susceptible to disturbance.

We recommend that earthwork activities at this site be completed during periods of predominantly dry

weather. During dry weather, site soils will be less susceptible to disturbance, provide better support for

construction equipment, and be more likely to meet the required compaction criteria.

If earthwork must occur during wet weather, we recommend that contingencies be included to account for

additional management of materials and over-excavation and replacement of saturated and disturbed

soils. Additionally, if wet weather construction is proposed or required, we recommend considering for a

“net cut” site rather than a balanced cut and fill site, to reduce the amount of overall soil management and

less handling of materials exposed to wet conditions.

4.7.3 Cut and Fill Slopes

To maintain site grading and provide safe working conditions, we recommend planning for temporary

excavations and cut slopes to be inclined no steeper than about 1.5H:1V. Flatter cut slopes will be

necessary where seepage occurs or if surface surcharge loads are anticipated. If 1.5H:1V temporary slopes

are not feasible, temporary shoring, such as a soldier pile or soil nail wall, may be necessary. We envision

this may be the case when excavating the basement for the new Administration Building due to proximity

of surrounding buildings and other improvements. Depending on the depth of excavation, and site layout,

cut slopes in combination with shoring elements, or use of ecology block wall systems may also be

appropriate for temporary shoring. Where dense glacial till deposits are present, there could be an option

to construct steeper 1H:1V temporary slopes provided that these conditions are verified as a final

geotechnical study and during construction.

We recommend permanent slopes with maximum inclination of about 2H:1V be considered for preliminary

planning purposes. Where 2H:1V permanent slopes are not feasible, protective facings and/or retaining

structures should be considered. Where access for landscape maintenance is desired, we recommend a

maximum inclination of 3H:1V. Flatter cut slopes or additional drainage measures could be necessary

where seepage occurs or if surface surcharge loads are anticipated.

4.7.4 Groundwater Handling

The level of effort required for groundwater management during construction will depend to a great extent

on the time of year during which construction is completed. Groundwater handling needs will typically be

lower during the late summer and early fall months. We recommend earthwork be completed in the late

summer or early fall months when the groundwater level is typically at its lowest elevation and to take

advantage of generally dry prevailing conditions.

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Page 11

Shallow perched groundwater should be expected to be present where more permeable layers are

underlain by less permeable layers, specifically in areas where fill or weathered zones are over undisturbed

glacial till. Based on our experience in similar glacial soil conditions, slow to moderate groundwater seepage

(3 gallons per minute [gpm] or less) is typical in these soil types, particularly during the wet season. We

anticipate that this type of shallow perched groundwater, if encountered, can be handled adequately with

sumps, pumps, and/or diversion ditches, as necessary.

As described above, static groundwater at the site is anticipated to be deeper than 10 feet below existing

site grades. For preliminary planning purposes, anticipate that excavations extending 10 feet below existing

site grades could require dewatering systems, groundwater cut off elements, wells, or additional sumps in

order to maintain dry conditions. Ultimately, completing subsurface explorations will provide better

information on groundwater levels at the site.

4.7.5 Fill Materials and Compaction

4.7.5.1

REUSE OF ON-SITE SOILS AS STRUCTURAL FILL

We anticipate the majority of the site footprint is underlain by glacial till (Qgt) deposits, which typically

consist of a mixture of silt, sand, gravel and cobbles. Glacial till soils can be considered for reuse as

structural fill provided, they can be adequately moisture conditioned, placed, and compacted, as

recommended and do not contain organic or other deleterious material. Site soils will likely be very difficult

or impossible to properly compact when wet and we recommend they be avoided for reuse if earthwork is

planned during wet weather months.

In addition, it is possible that existing soils will be generated at moisture contents above what is optimum

for compaction. In this case, the soils would need to be moisture conditioned prior to re-use. Space for

drying out material during dryer weather or covering on-site materials generated during wet weather should

be considered and incorporated into schedules and budgets. During wetter or even slightly colder times of

year, accommodations to cover stockpiled material generated on site that will be used as structural fill

should be planned.

If earthwork occurs during a typical wet season, or if the soils are persistently wet and cannot be dried back

due to prevailing wet weather conditions, we recommend project budgets include contingencies for using

imported materials as structural fill.

4.7.5.2

IMPORT STRUCTURAL FILL

Imported structural fill should be free of debris, organic contaminants, and rock fragments larger than

6 inches. For most applications, we recommend that structural fill consist of material similar to “Select

Borrow” or “Gravel Borrow” as described in Section 9-03.14 of the Washington State Department of

Transportation (WSDOT) Standard Specifications.

If imported fill is needed during wet weather conditions, we recommend using fill consisting of well-graded

sand and gravel or crushed rock with a maximum particle size not exceeding 6 inches and less than

5 percent fines by weight based on the minus ¾-inch fraction. In our opinion, material conforming to

WSDOT Standard Specifications Sections 9-03.9 (Aggregates for Ballast and Crushed Surfacing), 9-03.10

(Aggregate for Gravel Base) and 9-03.14 (Borrow) are suitable for use as imported fill material during wet

weather, with the exception that the fines content should be limited to 5 percent or less based on the minus

¾-inch fraction.

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4.7.5.3

Page 12

TOPSOIL AND STRIPPINGS

Topsoil and strippings (e.g., sod and forest duff) may be placed on site provided they are placed in

non-structural areas that can tolerate some long-term total and differential settlements. Settlements of

organic-rich soils are highly variable and difficult to quantify. Settlement could continue for several years

after construction is completed as the organics break down and decompose. Alternatively, topsoil strippings

can be hauled off site.

4.7.5.4

FILL COMPACTION

In general, we recommend that all structural fills be compacted to at least 95 percent of the maximum dry

density (MDD) based on ASTM D-1557. Provisions for less compaction effort may be considered and

reduced to about 92 percent, where deeper fills are placed, such as below pavement areas. Typically,

landscape areas require about 85 to 90 percent compaction efforts.

5.0 Recommendations for Further Studies

Final site design will need explorations to develop recommendations for foundation support, shoring design

(where necessary), seismic design parameters, and stormwater infiltration. Overall, we recommend

substantial structures include borings as a final consideration for subsurface explorations and geotechnical

design. Borings are typically best suited where refined geotechnical design parameters are necessary. For

example, soil strength parameters and seismic Site Class can be determined from correlations to the

standard penetration test (SPT) completed during sampling. Borings can also be helpful where limited

surface disturbance is necessary, and/or where excavations are planned to be deeper than about 8 to

10 feet. For temporary shoring, borings will be needed for use by shoring designers and should typically

extend at least two times the depth of the proposed excavation and be spaced no greater than about 200

feet of wall length. We recommend borings be considered, at or near corners of proposed buildings, and

one in the center, as applicable, for the majority of structures proposed for this project.

Converting a boring(s) to a groundwater monitoring well(s) is also suggested as it could help characterize

fluctuations in groundwater levels for general construction and temporary excavations and help with design

for shoring, permanent below-grade walls, and for determining depth limits of infiltration facilities. A

piezoelectric pressure transducer can be installed in a monitoring well to record groundwater levels at

programmed intervals throughout the seasons.

For near-grade smaller structures, test pits in many cases may be appropriate for subsurface exploration

and geotechnical design. Test pits are also the primary investigation technique for stormwater infiltration

studies. If stormwater infiltration is included in project design, we recommend field testing, such as Pilot

Infiltration Tests (PITs), be completed to determine design infiltration rates. PITs should be completed within

the footprint of proposed infiltration facilities and at the proposed infiltration depths. PITs are best

completed once preliminary site planning and layout has occurred.

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Page 13

6.0 Limitations

We have prepared this report for the exclusive use of Stantec and the Port Gamble S’Klallam Tribe for the

Administrative Campus Master Plan project in Kingston, Washington. Stantec and the Port Gamble

S’Klallam Tribe may distribute copies of this report to authorized agents and regulatory agencies as may

be required for the project.

Within the limitations of scope, schedule and budget, our services have been executed in accordance with

generally accepted practices for geotechnical engineering in this area at the time this report was prepared.

The conclusions, recommendations, and opinions presented in this report are based on our professional

knowledge, judgment, and experience. No warranty, express or implied, applies to the services or this

report.

Any electronic form, facsimile, or hard copy of the original document (email, text, table and/or figure), if

provided, and any attachments are only a copy of the original document. The original document is stored

by GeoEngineers, Inc. and will serve as the official document of record.

Please refer to Appendix A titled “Report Limitations and Guidelines for Use” for additional information

pertaining to use of this report.

7.0 References

American Society of Civil Engineers, 2016, “Minimum Design Loads and Associated Criteria for Buildings

and Other Structures, ASCE/SE 7-2016.”

International Code Council, 2021, “International Building Code.”

Kitsap County Department of Community Development. 2017. “Critical Areas, Kitsap County, Washington.”

April 27.

Kitsap County Department of Community Development. 2017. “Geologically Hazardous Map, Erosion

Hazards, Kitsap County, Washington.” February 23.

Kitsap County Department of Community Development. 2017. “Geologically Hazardous Map, Landslide

Hazards, Kitsap County, Washington.” February 23.

Kitsap County Department of Community Development. 2017. “Geologically Hazardous Map, Seismic

Hazards, Kitsap County, Washington.” February 23.

United States Department of Agriculture, Natural Resources Conservation Service. 2024. Web Soil Survey.

https://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx, accessed May 6 and 7, 2024.

United States Department of the Interior, Bureau of Indian Affairs. 2011. “AS BUILTS, ADMINISTRATION

CAMPUS PROJECT: CIVIL DRAWINGS, PORT GAMBLE INDIAN RESERVATION.” Project Number P10

09000. November 7.

File No. 0181-010-00

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Page 14

Washington State Department of Natural Resources. 2024. Washington Geologic Information Portal.

https://geologyportal.dnr.wa.gov/, accessed May 6, 2024.

Washington State Department of Transportation. 2024. “Standard Specifications for Road, Bridge, and

Municipal Construction.” Washington State Department of Transportation and the American Public

Works Association, M41-10.

File No. 0181-010-00

Figures

Legend

Site Boundary

Subarea Boundary

Subarea 3

Little B

Source(s):

· Aerial from Microsoft Bing

Coordinate System: WA State Plane, North Zone, NAD83, US Foot

Disclaimer: This figure was created for a specific purpose and project. Any use of this figure for

any other project or purpose shall be at the user's sole risk and without liability to GeoEngineers.

The locations of features shown may be approximate. GeoEngineers makes no warranty or

representation as to the accuracy, completeness, or suitability of the figure, or data contained

therein. The file containing this figure is a copy of a master document, the original of which is

retained by GeoEngineers and is the official document of record.

Subarea 1

120

Feet

Port G

Site Plan

amble

P:\0\0181010\CAD\00\Geotech\018101000_F02_Site Plan.dwg 2 Date Exported:5/13/2024 7:49 AM - by Mike C. Rau

d. NE

oston R

Subarea 2

Port Gamble S’Klallam Tribe

Administrative Campus Master Plan

Kingston, Washington

Figure 2

00181-010-00 Date Exported: 05/06/2024

Stream or Creek Ravine

Site

Stream or Creek

Shallow Ravine

Lidar Map

Notes:

1. This drawing has been reproduced from mapping available online by the Washington State Department of Natural Resources.

GeoEngineers cannot warrant or guarantee the accuracy or completeness of information provided or compiled by others.

2. This drawing is for information purposes. It is intended to assist in showing features discussed in an attached document.

GeoEngineers, Inc. cannot guarantee the accuracy and content of electronic files. The master file is stored by GeoEngineers, Inc. and

will serve as the official record of this communication.

Data Source: 1:100,000-scale Geologic Map, Washington State Department of Natural Resources online Geologic Information Portal

Port Gamble S’Klallam Tribe - Administrative

Campus Master Plan, Kingston, Washington

Figure 3

00181-010-00 Date Exported: 05/06/2024

Map Symbol

Geologic Unit Name

Qgo

Continental glacial outwash, Fraser-age

Qgt

Continental glacial till, Fraser-age

Qgp

Continental glacial drift, pre-Fraser

Qga(t)

Advance continental glacial outwash,

Fraser-age

Site

Qgo

Qgt

Qga(t)

Qgp

Geologic Map

Notes:

1. This drawing has been reproduced from mapping available online by the Washington State Department of Natural Resources.

GeoEngineers cannot warrant or guarantee the accuracy or completeness of information provided or compiled by others.

2. This drawing is for information purposes. It is intended to assist in showing features discussed in an attached document.

GeoEngineers, Inc. cannot guarantee the accuracy and content of electronic files. The master file is stored by GeoEngineers, Inc. and

will serve as the official record of this communication.

Data Source: 1:100,000-scale Geologic Map, Washington State Department of Natural Resources online Geologic Information Portal

Port Gamble S’Klallam Tribe - Administrative

Campus Master Plan, Kingston, Washington

Figure 4

00181-010-00 Date Exported: 05/06/2024

Map

Symbol

Soil Unit Name

Parent Material

Indianola: Glacial

outwash

Indianola-Kitsap

complex

Kitsap: Lacustrine

deposits with

volcanic ash in the

upper part

Lacustrine deposits

Kitsap silt loam

with volcanic ash in

Site

the upper part

Ragnar fine sandy

loam

Glacial outwash with

some volcanic ash

in the upper part

Soil Survey Map

Notes:

1. This drawing has been reproduced from the United States Department of Agriculture (USDA) Natural Resources Conservation Service

(NRCS) Web Soil Survey (WSS). GeoEngineers cannot warrant or guarantee the accuracy or completeness of information provided or

compiled by others.

2. This drawing is for information purposes. It is intended to assist in showing features discussed in an attached document.

GeoEngineers, Inc. cannot guarantee the accuracy and content of electronic files. The master file is stored by GeoEngineers, Inc. and

will serve as the official record of this communication.

Data Source: Parent Material, USDA NRCS Web Soil Survey

Port Gamble S’Klallam Tribe - Administrative

Campus Master Plan, Kingston, Washington

Figure 5

00181-010-00 Date Exported: 05/06/2024

Site

Seismic Hazards Map

Notes:

1. This drawing has been reproduced from seismic hazard mapping available online by the Washington State Department of Natural

Resources. GeoEngineers cannot warrant or guarantee the accuracy or completeness of information provided or compiled by others.

2. This drawing is for information purposes. It is intended to assist in showing features discussed in an attached document.

GeoEngineers, Inc. cannot guarantee the accuracy and content of electronic files. The master file is stored by GeoEngineers, Inc. and

will serve as the official record of this communication.

Data Source: Washington State Department of Natural Resources online Geologic Information Portal

Port Gamble S’Klallam Tribe - Administrative

Campus Master Plan, Kingston, Washington

Figure 6

Appendices

Appendix A

Report Limitations and Guidelines for Use

Port Gamble S’Klallam Tribe c/o Stantec Consulting Services, Inc. | May 15, 2024

Page A-1

Appendix A

Report Limitations and Guidelines for Use1

This appendix provides information to help you manage your risks with respect to the use of this report.

Read These Provisions Closely

It is important to recognize that the geoscience practices (geotechnical engineering, geology and

environmental science) rely on professional judgment and opinion to a greater extent than other

engineering and natural science disciplines, where more precise and/or readily observable data may exist.

To help clients better understand how this difference pertains to our services, GeoEngineers includes the

following explanatory “limitations” provisions in its reports. Please confer with GeoEngineers if you need to

know more how these “Report Limitations and Guidelines for Use” apply to your project or site.

Geotechnical Services Are Performed for Specific Purposes, Persons and Projects

This report has been prepared for the exclusive use of Stantec and the Port Gamble S’Klallam Tribe for the

Administrative Campus Master Plan project. Stantec and the Port Gamble S’Klallam Tribe may distribute

copies of this report to authorized agents and regulatory agencies as may be required for the project. This

report is not intended for use by others, and the information contained herein is not applicable to other

sites.

GeoEngineers structures our services to meet the specific needs of our clients. For example, a geotechnical

or geologic study conducted for a civil engineer or architect may not fulfill the needs of a construction

contractor or even another civil engineer or architect that are involved in the same project. Because each

geotechnical or geologic study is unique, each geotechnical engineering or geologic report is unique,

prepared solely for the specific client and project site. Our report is prepared for the exclusive use of our

Client. No other party may rely on the product of our services unless we agree in advance to such reliance

in writing. This is to provide our firm with reasonable protection against open-ended liability claims by third

parties with whom there would otherwise be no contractual limits to their actions. Within the limitations of

scope, schedule and budget, our services have been executed in accordance with our Agreement with the

Client and generally accepted geotechnical practices in this area at the time this report was prepared. This

report should not be applied for any purpose or project except the one originally contemplated.

A Geotechnical Engineering or Geologic Report Is Based on a Unique Set of

Project-specific Factors.

This report has been prepared for the Port Gamble S’Klallam Tribe - Administrative Campus Master Plan

project located in Kingston, Washington. GeoEngineers considered a number of unique, project-specific

factors when establishing the scope of services for this project and report. Unless GeoEngineers specifically

indicates otherwise, it is important not to rely on this report if it was:

1 Developed based on material provided by GBA, GeoProfessional Business Association; www.geoprofessional.org

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Port Gamble S’Klallam Tribe c/o Stantec Consulting Services, Inc. | May 15, 2024

Page A-2

■ Not prepared for you,

■ Not prepared for your project,

■ Not prepared for the specific site explored, or

■ Completed before important project changes were made.

For example, changes that can affect the applicability of this report include those that affect:

■ The function of the proposed structure;

■ Elevation, configuration, location, orientation or weight of the proposed structure;

■ Composition of the design team; or

■ Project ownership.

If changes occur after the date of this report, GeoEngineers cannot be responsible for any consequences

of such changes in relation to this report unless we have been given the opportunity to review our

interpretations and recommendations. Based on that review, we can provide written modifications or

confirmation, as appropriate.

Environmental Concerns are Not Covered

Unless environmental services were specifically included in our scope of services, this report does not

provide any environmental findings, conclusions, or recommendations, including but not limited to, the

likelihood of encountering underground storage tanks (USTs) or regulated contaminants.

Information Provided by Others

GeoEngineers has relied upon certain data or information provided or compiled by others in the

performance of our services. Although we use sources that we reasonably believe to be trustworthy,

GeoEngineers cannot warrant or guarantee the accuracy or completeness of information provided or

compiled by others.

Subsurface Conditions Can Change

This geotechnical or geologic report is based on conditions that existed at the time the study was performed.

The findings and conclusions of this report may be affected by the passage of time, by man-made events

such as construction on or adjacent to the site, new information or technology that becomes available

subsequent to the report date, or by natural events such as floods, earthquakes, slope instability or

groundwater fluctuations. If more than a few months have passed since issuance of our report or work

product, or if any of the described events may have occurred, please contact GeoEngineers before applying

this report for its intended purpose so that we may evaluate whether changed conditions affect the

continued reliability or applicability of our conclusions and recommendations.

File No. 0181-010-00

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Page A-3

Geotechnical and Geologic Findings are Professional Opinions

Our interpretations of subsurface conditions are based on field observations from widely spaced sampling

locations at the site. Site exploration identifies the specific subsurface conditions only at those points where

subsurface tests are conducted or samples are taken. GeoEngineers reviewed field and laboratory data

and then applied its professional judgment to render an informed opinion about subsurface conditions at

other locations. Actual subsurface conditions may differ, sometimes significantly, from the opinions

presented in this report. Our report, conclusions and interpretations are not a warranty of the actual

subsurface conditions.

Geotechnical Engineering Report Recommendations are Not Final

We have developed the following recommendations based on data gathered from subsurface

investigation(s). These investigations sample just a small percentage of a site to create a snapshot of the

subsurface conditions elsewhere on the site. Such sampling on its own cannot provide a complete and

accurate view of subsurface conditions for the entire site. Therefore, the recommendations included in this

report are preliminary and should not be considered final. GeoEngineers’ recommendations can be

finalized only by observing actual subsurface conditions revealed during construction. GeoEngineers

cannot assume responsibility or liability for the recommendations in this report if we do not perform

construction observation.

We recommend that you allow sufficient monitoring, testing and consultation during construction by

GeoEngineers to confirm that the conditions encountered are consistent with those indicated by the

explorations, to provide recommendations for design changes if the conditions revealed during the work

differ from those anticipated, and to evaluate whether earthwork activities are completed in accordance

with our recommendations. Retaining GeoEngineers for construction observation for this project is the most

effective means of managing the risks associated with unanticipated conditions. If another party performs

field observation and confirms our expectations, the other party must take full responsibility for both the

observations and recommendations. Please note, however, that another party would lack our projectspecific knowledge and resources.

A Geotechnical Engineering or Geologic Report Could Be Subject to Misinterpretation

Misinterpretation of this report by members of the design team or by contractors can result in costly

problems. GeoEngineers can help reduce the risks of misinterpretation by conferring with appropriate

members of the design team after submitting the report, reviewing pertinent elements of the design team’s

plans and specifications, participating in pre-bid and preconstruction conferences, and providing

construction observation.

Give Contractors a Complete Report and Guidance

To help reduce the risk of problems associated with unanticipated subsurface conditions, GeoEngineers

recommends giving contractors the complete geotechnical engineering or geologic report, including these

“Report Limitations and Guidelines for Use.” When providing the report, you should preface it with a clearly

written letter of transmittal that:

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Port Gamble S’Klallam Tribe c/o Stantec Consulting Services, Inc. | May 15, 2024

Page A-4

■ Advises contractors that the report was not prepared for purposes of bid development and that its

accuracy is limited; and

■ Encourages contractors to confer with GeoEngineers and/or to conduct additional study to obtain the

specific types of information they need or prefer.

Contractors are Responsible for Site Safety on Their Own Construction Projects

Our geotechnical recommendations are not intended to direct the contractor’s procedures, methods,

schedule or management of the work site. The contractor is solely responsible for job site safety and for

managing construction operations to minimize risks to on-site personnel and adjacent properties.

Biological Pollutants

GeoEngineers’ Scope of Work specifically excludes the investigation, detection, prevention or assessment

of the presence of Biological Pollutants. Accordingly, this report does not include any interpretations,

recommendations, findings or conclusions regarding the detecting, assessing, preventing or abating of

Biological Pollutants, and no conclusions or inferences should be drawn regarding Biological Pollutants as

they may relate to this project. The term “Biological Pollutants” includes, but is not limited to, molds, fungi,

spores, bacteria and viruses, and/or any of their byproducts.

A Client that desires these specialized services is advised to obtain them from a consultant who offers

services in this specialized field.

Geotechnical, Geologic and Environmental Reports Should Not Be Interchanged

The equipment, techniques and personnel used to perform an environmental study differ significantly from

those used to perform a geotechnical or geologic study and vice versa. For that reason, a geotechnical

engineering or geologic report does not usually relate any environmental findings, conclusions or

recommendations; e.g., about the likelihood of encountering USTs or regulated contaminants. Similarly,

environmental reports are not used to address geotechnical or geologic concerns regarding a specific

project.

File No. 0181-010-00

Natural

Resources

Assessment

Report

PORT GAMBLE S’KLALLAM TRIBE ADMINISTRATIVE CAMPUS MASTER PLAN

CHAPTER 6: APPENDICES

Memo

To:

Joe Sparr, Planning Director

From:

Port Gamble S’Klallam Tribe,

Kingston, WA

Project/File:

2042681800 - Task 1.4.2

Tim Nightengale; Darrell Rowe

(Stantec)

Bellevue, WA

Date:

June 19, 2024

Reference: Environmental Site Analysis (ESA) for the Port Gamble S'Klallam Tribe Administrative

Campus

CONTENTS

PROJECT DESCRIPTION / PURPOSE AND NEED STATEMENT ......................................................................... 1

ENVIRONMENTAL IMPACTS .................................................................................................................................. 4

2.1

2.2

Methods .............................................................................................................................................................. 4

Existing Conditions and Sensitive Areas............................................................................................................. 4

2.2.1

Subarea 1 ................................................................................................................................... 4

2.2.2

Subarea 2 ................................................................................................................................... 6

2.2.3

Subarea 3 ................................................................................................................................... 6

ALTERNATIVES....................................................................................................................................................... 8

REFERENCES.......................................................................................................................................................... 9

Project Description / Purpose and Need Statement

Stantec and Ferguson Architects are contracted to create an Updated Master Plan for the Port Gamble

S’Klallam Tribe Administrative Campus (Figure 1), focusing on planned improvements and land uses for

three areas of the campus, shown in Figure 2 as Subarea 1, 2, and 3. Subareas 1 and 2 will include future

improvements to the new Administrative Campus, including a new Administration building, community

center, gym, village commons (plaza), and planned subterranean parking garage, along with additional

parking, sidewalks, and park space. Subarea 3 will include structures to support Tribal Public Works and

Facilities Operations and event space parking.

As stated in Chapter 24.04.07 of the Port Gamble S’Klallam Tribe (PGST) Law and Order Code (LOC), the

purpose of the Environmental Site Analysis (ESA) is to “identify design modifications or mitigation measures

that will avoid or minimize adverse environmental impacts and achieve compliance with the purpose and

standards of this title.”

This ESA report has been prepared to: 1) identify any sensitive areas present within and around each of the

proposed subareas on the Administrative Campus; 2) provide an analysis of any potential adverse

environmental impacts by applying the Environmental Standards detailed in Chapter 24.08 of the PGST

LOC; and 3) provide recommendations for potential mitigation or minimization of any potential adverse

environmental impacts. These findings will be applied to the conceptual site planning and incorporated into

the revised Master Plan.

June 19, 2024

Joe Sparr, Planning Director

Page 2 of 9

Reference: 2042681800

Figure 1. Existing Vicinity Map (Source: Google Earth & PGST Master Plans)

June 19, 2024

Joe Sparr, Planning Director

Page 3 of 9

Reference: 2042681800

Figure 2. Subarea Map for the Administrative Campus (Source: Google Earth)

June 19, 2024

Joe Sparr, Planning Director

Page 4 of 9

Reference: 2042681800

Environmental Impacts

2.1

Methods

Stantec biologists first performed a desktop review of available public-domain information prior to their

critical areas site visit. These online sources included U.S. Fish and Wildlife Service (USFWS) National

Wetland Inventory (NWI) maps (USFWS 2024a), Washington Department of Fish and Wildlife’s (WDFW)

Statewide Washington Integrated Fish Distribution (SWIFD) mapping (WDFW 2024b), Kitsap County’s GIS

website (maps.kirklandwa.gov) for wetlands, streams, floodplains, and shoreline designations.

A US Fish and Wildlife Service (USFWS) Information Planning and Conservation (IPAC) report was

downloaded from their Trust Resources Database to determine any listed species or designated critical

habitat areas within the vicinity of or in the project area (USFWS 2024b). Also, WDFW’s Priority Habitats

and Species (PHS) lists were downloaded and an official PHS report was obtained for the project area

(WDFW 2024a). GIS maps created by Soundview Consultants showing streams and wetlands on the

Reservation were also reviewed by Stantec biologists for a general information about the Little Boston

Creek, and if any wetlands were within or near the Project Area. Finally, Stantec biologists reviewed the

Environmental Protection regulations (Title 24) within the PGST LOC for details on the environmental

standards to be applied.

On April 11, 2024, Stantec biologists Tim Nightengale, and Darrell Rowe walked Administrative Campus,

around the perimeter of the campus, as well as the length of Little Boston Creek from the mouth to Little

Boston Road, and the strip of land along the bluff on the west side of Little Boston Road. Using an Arrow

100 GNSS receiver in tandem with an iPhone12, Stantec biologists digitally recorded coordinates at each

photograph taken, capturing images of the creek, stormwater drainage features, drainage ditches located

around the perimeter of the ball field, and any potential wetlands and associated vegetation, specifically at

areas where sensitive areas and their buffers would potentially intersect with Subareas 1, 2, or 3. Using the

GPS Kit app, photographs were taken and GPS-located. Attachment A contains representative

photographs from this site visit.

2.2

Existing Conditions and Sensitive Areas

The Administrative Campus is approximately 22.0 acres, currently the located along the eastern side of

Little Boston Road NE before it turns east and then north (Figures 1 and 2). Subarea 1 is approximately 2.9

acres and contains the Administration Building, Gym, Kitchen, Natural Resources Department building, and

playground area. Subarea 2, approximately 4.0 acres, is located to the west of Little Boston Road NE, and

runs along the bluff bordering Port Gamble Bay. Subarea 2 contains the Tribal Arts Center and Tribal

Cemetery; the vacant residence pictured in Figure 2 had been demolished and cleared as of the April 2024

site visit. Subarea 3 is approximately 1.1 acres in size, located to the west of the ball field and south of Little

Boston Road NE. The subarea contains several maintenance buildings and a parking area.

2.2.1

SUBAREA 1

Initial desktop review of critical areas within the vicinity of the Administration Campus revealed that the

closest critical area near Subarea 1 was an unnamed fish bearing stream to the south of the property

(Figure 3). The designated 150-foot stream buffer for fish bearing streams does not extend into Subarea 1,

and only minimally extends onto the campus, near the equipment yard of the Natural Resources Laboratory

area. Stantec biologists walked the perimeter of the campus to observe any other possible critical areas

Legend

Fish bearing stream

Wetland

Wetland buffer (50 ft)

Parcels

300

Feet

(At original document size of 8.5x11)

1:3,000

Bluff buffer (150 ft)

Stream buffers (150 ft fish bearing and 100 ft non fish bearing)

150

ffi

�

� Stantec

Project Location

Prepared by NZ on 2024.06.18

Kitsap County, WA

Client/Project

Notes

1. Coordinate System: NAO 1983 StatePlane

Washington North FIPS 4601 Feet

2. Data Sources:

3. Background:

Port Gamble S'Klallum Tribe

Figure No.

Title

Critical Areas and Buffers Administrative Campus

Disclaimer: This document has been prepared based on information provided by others as cited in the Notes section. Stantec has not verified the accuracy and/or completeness of this information and shall not be responsible for any errors

or omissions which may be incorporated herein as a result. Staniec assumes no responsibility for data supplied in electronic format, and the recipient accepts full responsibility for verifying the accuracy and completeness of the data.

June 19, 2024

Joe Sparr, Planning Director

Page 6 of 9

Reference: 2042681800

that would extend buffers into Subarea 1. Biologists did trace drainage ditches along the perimeter, from the

ball field perimeter, around the southeastern edge of the campus and down to the Natural Resources

Laboratory area (see Attachment A, Photos 12-18). A stormwater drainage system appeared to be recently

installed, with lines running from the ball field down to a storm drain near the Natural Resources Laboratory,

which connected to the stormwater system and eventually flows into a drainage ditch that joins with the

perimeter drainage ditch flow at the northwest corner of the Natural Resources Laboratory area (see

Attachment A, Photos 19-21). The drainage ditches merge and flow into a thicket of Himalayan blackberries

(Rubus armeniacus). Water was not observed beyond this point. Flow lines, signs of swept-away leaf litter,

and deposited sediment was observed along the forested floor to the south of the campus area, but Stantec

biologists did not observe any established stream bed or material, and no signs of wetland (hydrophytic)

indicator plant species that would suggest stream or wetland conditions. It is likely the stormwater and

drainage flows are newer and are infrequent, and that most flows quickly infiltrate into the ground.

Therefore, no critical areas or buffers were observed that would be impacted by development within

Subarea 1.

2.2.2

SUBAREA 2

Initial desktop review of critical areas within the vicinity of the Administration Campus revealed that the

closest critical area near Subarea 2 was the marine bluff along the western edge of the subarea (Figure 2).

Stantec biologists investigated the extent of Subarea 2 to observe any other possible critical areas or

concerns. The top of slope of the bluff was generally 15 feet west of the cleared and mowed limits of the

area. Towards the southern end of Subarea 2, the top of the bluff was typically covered with Himalayan

blackberry, with red alder (Alnus rubra) and Western red cedar trees (Thuja plicata) trees further

downslope. As the biologists neared the Tribal Art Center, the top of slope vegetation shifted to Nootka rose

(Rosa nutkana) clusters, salal (Gaultheria shallon), and low Oregon grape (Mahonia nervosa), with larger

Douglas fir trees (Pseudotsuga menziesii) and a more forested slope existing towards the northern end of

Subarea 2 as it neared Little Boston Creek.

The Environmental Standards stated in Chapter 24.08.01(g) of the PGST LOC give the marine bluff at 150foot setback limit, measured from the mean high-water level or at a distance equal to the height of the bluff,

whichever is greater. The height of the bluff is around 60-70 feet, so a 150-foot buffer was extended inland

from the boundary limit of the reservation (and western parcel boundaries), as shown in Figure 3. The

Marine Bluff Setback regulations also indicate that this applies to structures and activities that are not

marine shoreline dependent, which would include the proposed development use of Subarea 2, with

additional parking and park space. The setback limit appears to extend approximately 30-40 feet beyond

the top of the bluff, leaving the cemetery and art center largely outside of the setback.

2.2.3

SUBAREA 3

Initial desktop review of critical areas within the vicinity of the Administration Campus revealed that Little

Boston Creek is immediately north of the property and could project a stream buffer into Subarea 3. Stantec

biologists investigated Little Boston Creek during the site visit, following it from the creek mouth and the

hatchery, upstream to the diversion structure which routes water to the hatchery. The stream was not

accessible through the impounded area behind the diversion structure, so Stantec biologists walked around

to Little Boston Road NE and re-entered further upstream. The stream lies within a ravine with steep

slopes, with numerous Western red cedar and Douglas fir trees with an understory Western sword fern

(Polystichum munitum). The streambanks featured salmonberry (Rubus spectabilis), osoberry (Oemleria

cerasiformis), vine maple (Acer circinatum), lady fern (Athyrium filix-femina), sword ferns, Western red

cedars, with clusters of youth-on-age (Tolmiea menziesii) and false lily-of-the-valley (Maianthemum

dilatatum). See Attachment A for site photos 1-8.

June 19, 2024

Joe Sparr, Planning Director

Page 7 of 9

Reference: 2042681800

Exiting the stream at its crossing under Little Boston Road NE, Stantec biologists continued along the road,

south towards the ball field. The shallow roadside ditch along the east side of the road was flowing north,

with water running to the creek. Following the ditch further, flow was traced to a potential wetland area

located along the east side of the gravel access road leading to Subarea 3 and the ball field, shown in

Figure 3 (Attachment A, Photos 9-11). The area had standing water and featured filamentous algae growing

throughout, strong indicators of wetland conditions. However, no formal delineation or hydric soil test was

performed; a formal wetland delineation of this feature should be performed to confirm. The biologists

continued to follow the perimeter of the ball field, and found that a shallow ditch was excavated around the

perimeter, possibly to aid in the drainage of the ball field area. The ditch was nearly half full of water at the

time of the site visit. Water likely was draining down to the potential wetland area and then continuing to the

creek via the roadside ditch.

The Environmental Standards stated in Chapter 24.08.01(c) of the PGST LOC places a natural buffer of

150 feet on all fish bearing streams, including Little Boston Creek, and a buffer of 50 feet on all wetlands.

Figure 3 shows the application of this buffer limit on Little Boston Creek, revealing that the buffer extends

across Little Boston Road NE and onto the Administrative Campus, particularly into the northern portions of

Subarea 3 along the roadway. The buffer from the potential wetland also extends across the access road

and into Subarea 3. The PGST LOC does not indicate how buffers should be applied when crossing

existing substantial improvements (typically public infrastructure or buildings), termed “interrupted buffers.”

Other municipal codes and shoreline master programs (SMPs) were reviewed for interrupted buffer

regulations. Washington State Department of Transportation (WSDOT) only applies buffer areas on the

same side of existing roadways as the associated critical area feature (e.g., wetlands or streams). The

reasoning for this decision is that “buffer areas physically separated from a wetland or other water by an

existing road can’t provide functions (such as screening, noise reduction, and water quality improvement)

for the sensitive area” (WSDOT 2023); however, their guidelines also say to always review and apply

regulations from the local municipal code.

The City of Bremerton’s SMP contains regulation for interrupted buffers in Chapter 7.010(b)(3), stating:

“When a buffer contains an existing legally established public or private road, the Director may

allow development on the landward side of the road provided that the development will not have a

detrimental impact to the shoreline. The applicant may be required to provide a report to describe

the potential impacts. In determining whether a report is necessary, the City shall consider the

extent and permanence of the buffer interruption and potential impact on shoreline ecological

functions.”

The City of Tacoma’s Municipal Code (Chapter 3.11, Critical Areas Preservation) also contains similar

language, detailing that where “proposed activities that are within the critical area or buffer but are

separated from the remaining critical area by a permanent substantial improvement, or are located in an

existing permanent substantial improvement, may be allowed provided that the detrimental impact to the

critical area does not increase.” The City of Tacoma also evaluates whether there is a potential of a

hydrologic, geologic, and/or biological habitat connection along with the extent and permanence of the

interruption.

As a final example of interrupted buffer regulations, the City of Tukwila establishes an administrative waiver

process for an interrupted buffer, using criteria that are similar to those stated by Tacoma and Bremerton

regulations. To qualify for the waiver, the existing legal improvement creates a substantial barrier to the

buffer function; the interrupted buffer does not provide additional protection of the critical area from the

proposed development; and the interrupted buffer does not provide significant hydrological, water quality,

and wildlife buffer functions relating to the portion of the buffer adjacent to the critical area.

June 19, 2024

Joe Sparr, Planning Director

Page 8 of 9

Reference: 2042681800

Given that both the stream buffer and the buffer from the potential wetland extend across existing

roadways, the interrupted buffer scenario is applicable. It is unlikely that potential buffer area within

Subarea 3 provides additional protection to Little Boston Creek or the potential wetland area or provides

significant hydrological, water quality or wildlife habitat functions to those critical areas. As such, the

functional buffer limits likely end at the roadway edge, and do not extend across the roadway into Subarea

3, any decision would need to be made at the discretion of Planning Director, in consultation with the

Natural Resources Department.

Alternatives

Review of the critical areas within and in the surrounding adjacent areas of the Administrative Campus

during the April 11, 2024 site visit revealed no critical areas or buffers within Subarea 1, but a protective

setback limit from the marine bluff in Subarea 2, and potential buffer areas from Little Boston Creek and a

potential wetland area extending into Subarea 3.

For development within Subarea 2, avoidance of construction within the setback limit should be avoided or

minimized to the greatest extent possible. Should development plans extend into the setback, a

geotechnical review should be conducted to determine any impacts to the slope stability and potential for

erosion impacts. Construction activities near the setback limit should implement temporary erosion and

sediment control (TESC) plans using appropriate storm water Best Management Practices (BMPs; silt

fencing, straw wattles, clean gravel bags, etc.) to avoid and minimize contaminant-laden stormwater from

leaving the Project area. Post-construction activities should include a restoration of vegetation to the top of

the bluff, which would include the removal of invasive plants such as the Himalayan blackberries and scotch

broom (Cytisus scoparius), and enhancements with native plants that would be suitable for the bluff and

marine shoreline habitat.

For development within Subarea 3, mitigation efforts will depend on how the Planning Director and Natural

Resources Department will treat the interrupted buffers that extend into the subarea. At a minimum, any

construction activities should implement TESC plans using appropriate storm water BMPs (silt fencing,

straw wattles, clean gravel bags, etc.) to avoid and minimize contaminant-laden stormwater from leaving

the Project area and entering the potential wetland and roadside ditch, eventually leading to Little Boston

Creek. Additional BMPs would include wheel washes to prevent sediment from tracking out on tires and

sweeping Little Boston Creek Road to prevent any sediment runoff from entering the buffer on the stream

side of the road. Post-construction activities should include a restoration of vegetation on the other side of

the road to enhance and restore buffer functions to the existing buffer. Efforts would include the removal of

invasive plants, replacing them with native plants to match the existing riparian vegetation.

Should the decision be to extend the buffer areas into Subarea 3, avoidance or minimization would require

no structures or development of the northern and eastern edges of the subarea. If that is not possible, a

recommendation would be to employ buffer averaging, which would reduce the standard buffer width of the

stream or wetland in the subarea back to the road edge, and then increase the buffer width in other

locations by an equal or greater amount of area. Those new buffer areas would be receive vegetation

restoration or enhancements to provide protection for water quality and habitat to the stream or wetland.

June 19, 2024

Joe Sparr, Planning Director

Page 9 of 9

Reference: 2042681800

References

United States Fish and Wildlife Service (USFWS). 2024a. National Wetland Inventory (NWI) online maps.

< https://fwsprimary.wim.usgs.gov/wetlands/apps/wetlands-mapper/ > Accessed May 2024.

USFWS. 2024b. Information for Planning and Consultation (IPAC).< https://ipac.ecosphere.fws.gov/ >

Accessed June 2024.

Washington Department of Fish and Wildlife (WDFW). 2024a. WDFW’s Priority Habitats and Species (PHS

on the web) maps. < https://geodataservices.wdfw.wa.gov/hp/phs/ > Accessed June 2024.

WDFW. 2020b. Statewide Washington Integrated Fish Distribution (SWIFD) mapping.

< https://geo.nwifc.org/swifd/ > Accessed June 2024.

Washington State Department of Transportation (WSDOT). (2023). How to document buffers for wetlands &

other waters. WSDOT Environmental Services Office. Updated April 2023.

< https://wsdot.wa.gov/sites/default/files/2021-10/Env-Wet-DelinGuideRdwyBuffer.pdf > Accessed

June 2024.

Attachment A. Administrative Campus Site Visit Photo Log

Figure A-1 Administrative Campus Overview Map with Photo Points.

Environmental

Site Assessment

Report

PORT GAMBLE S’KLALLAM TRIBE ADMINISTRATIVE CAMPUS MASTER PLAN

CHAPTER 6: APPENDICES

Phase I Environmental Site

Assessment

Port Gamble S'Klallam Tribe

Subarea 2 and 3

Kingston, Washington 98346

Report Date: April 25, 2024

ASTM Expiry Date: September 6, 2024

Prepared for:

Port Gamble S'Klallam Tribe

31912 Little Boston Road Northeast

Kington, Washington 98346

Prepared by:

Stantec Consulting Services Inc.

3400 188th Street SW, Suite 285

Lynnwood, Washington 98037

Project No.: 2042681800

Sign-off Sheet and Signatures of Environmental Professionals

This document entitled Phase I Environmental Site Assessment, Port Gamble S'Klallam Tribe, Subarea 2 and

3, Kingston, Washington 98346 was prepared by Stantec Consulting Services Inc. (“Stantec”) for the account

of Port Gamble S'Klallam Tribe (the “Client”). The conclusions in the Report are Stantec’s professional

opinion, as of the time of the Report, and concerning the scope described in the Report. The opinions in the

document are based on conditions and information existing at the time the scope of work was conducted and

do not take into account any subsequent changes. The Report relates solely to the specific project for which

Stantec was retained and the stated purpose for which the Report was prepared. The Report is not to be used

or relied on for any variation or extension of the project, or for any other project or purpose, and any

unauthorized use or reliance is at the recipient’s own risk.

Stantec has assumed all information received from the “Client” and third parties in the preparation of the

Report to be correct. While Stantec has exercised a customary level of judgment or due diligence in the use

of such information, Stantec assumes no responsibility for the consequences of any error or omission

contained therein.

This Report is intended solely for use by the Client in accordance with Stantec’s contract with the Client.

While the Report may be provided to applicable authorities having jurisdiction and others for whom the Client

is responsible, Stantec does not warrant the services to any third party. The report may not be relied upon by

any other party without the express written consent of Stantec, which may be withheld at Stantec’s discretion.

Prepared by:

Cyrus Gorman, LG

Senior Associate

Reviewed by:

Jamie Hoffman

Senior Environmental Specialist

Reviewed by:

Neil Doran

Principal

Project No.: 2042681800

PHASE I ENVIRONMENTAL SITE ASSESSMENT

Table of Contents

ACRONYMS / ABBREVIATIONS ................................................................................................. I

1.0

SUMMARY ..................................................................................................................... 1.1

2.0

2.1

2.2

2.3

2.4

INTRODUCTION ............................................................................................................ 2.3

SUBJECT PROPERTY DESCRIPTION......................................................................... 2.4

SPECIAL TERMS, CONDITIONS, AND ADDITIONAL ASSUMPTIONS....................... 2.5

EXCEPTIONS AND LIMITING CONDITIONS ............................................................... 2.5

PERSONNEL QUALIFICATIONS .................................................................................. 2.6

3.0

USER-PROVIDED INFORMATION ............................................................................... 3.1

4.0

4.1

RECORDS REVIEW ...................................................................................................... 4.1

PHYSICAL SETTING ..................................................................................................... 4.1

4.1.1

Subject Property Topography and Surface Water Flow ............................... 4.1

4.1.2

Regional and Subject Property Geology ...................................................... 4.1

4.1.3

Regional and Subject Property Hydrogeology .............................................. 4.1

FEDERAL, STATE AND TRIBAL ENVIRONMENTAL RECORDS ................................ 4.2

4.2.1

Listings for Subject Property ......................................................................... 4.2

4.2.2

Listings for Nearby Sites with Potential to Impact Subject Property ............. 4.2

LOCAL/REGIONAL ENVIRONMENTAL RECORDS ..................................................... 4.3

4.3.1

Port Game S’Klallam Tribe ........................................................................... 4.3

HISTORICAL RECORDS REVIEW................................................................................ 4.3

4.4.1

Land Title Records/Deeds ............................................................................ 4.3

4.4.2

Aerial Photographs ....................................................................................... 4.3

4.4.3

City Directories ............................................................................................. 4.4

4.4.4

Historical Fire Insurance Maps ..................................................................... 4.5

4.4.5

Historical Topographic Maps ........................................................................ 4.5

4.4.6

Other Historical Sources............................................................................... 4.5

4.2

4.3

4.4

5.0

5.1

5.2

5.3

5.4

5.5

5.6

5.7

5.8

SITE VISIT ..................................................................................................................... 5.7

SITE RECONNAISSANCE METHODOLOGY ............................................................... 5.7

GENERAL DESCRIPTION ............................................................................................ 5.7

HAZARDOUS SUBSTANCES AND PETROLEUM PRODUCTS .................................. 5.8

INTERIOR OBSERVATIONS ......................................................................................... 5.9

EXTERIOR OBSERVATIONS ....................................................................................... 5.9

UNDERGROUND STORAGE TANKS/STRUCTURES ............................................... 5.10

ABOVEGROUND STORAGE TANKS ......................................................................... 5.10

ADJOINING PROPERTIES ......................................................................................... 5.11

5.8.1

Current Uses of Adjoining Properties ......................................................... 5.11

5.8.2

Observed Evidence of Past Uses of Adjoining Properties .......................... 5.11

5.8.3

Pits, Ponds, or Lagoons on Adjoining Properties ....................................... 5.11

6.0

INTERVIEWS ................................................................................................................. 6.1

7.0

EVALUATION ................................................................................................................ 7.1

Project No.: 2042681800

PHASE I ENVIRONMENTAL SITE ASSESSMENT

7.1

7.2

7.3

FINDINGS AND OPINIONS ........................................................................................... 7.1

DATA GAPS ................................................................................................................... 7.1

CONCLUSIONS ............................................................................................................. 7.2

8.0

NON-SCOPE CONSIDERATIONS ................................................................................ 8.3

9.0

REFERENCES ............................................................................................................... 9.1

LIST OF FIGURES

FIGURE 1

Subject Property and Vicinity Map

FIGURE 2

Subject Property Layout Map

LIST OF APPENDICES

APPENDIX A

PHOTOGRAPHS OF THE SUBJECT PROPERTY AND VICINITY ........... A.1

APPENDIX B

STANTEC RESUMES ................................................................................. B.1

APPENDIX C

USER PROVIDED RECORDS .................................................................... C.1

APPENDIX D

ENVIRONMENTAL AGENCY DATABASE SEARCH REPORT ................ D.1

APPENDIX E

PGST RECORDS ........................................................................................ E.1

APPENDIX F

HISTORICAL RECORDS ............................................................................ E.1

Project No.: 2042681800

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Summary

April 25, 2024

Acronyms / Abbreviations

AAI

All Appropriate Inquiry

ACM

asbestos containing material

AST

aboveground storage tank

ASTM

ASTM International

BER

business environmental risk

bgs

below ground surface

CERCLA

Comprehensive Environmental Response, Compensation, and Liability Act

CFR

Code of Federal Regulations

CREC

controlled recognized environmental condition

DNR

Washington State Department of Natural Resources

ECHO

EPA’s Enforcement and Compliance History Online database

Ecology

Washington State Department of Ecology

EDR

Environmental Data Resource, Inc.

environmental professional

EPA

United States Environmental Protection Agency

ESA

environmental site assessment

HREC

historical recognized environmental condition

ft amsl

Feet above mean sea level

LUST

leaking underground storage tank

PGST

Port Gamble S'Klallam Tribe

PCB

polychlorinated biphenyl

RCRA

Resource Conservation Recovery Act

REC

recognized environmental condition

Stantec

Stantec Consulting Services Inc.

UST

underground storage tank

VEC

vapor encroachment condition

Project No.: 2042681800

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Summary

April 25, 2024

1.0

SUMMARY

Stantec Consulting Services Inc. (Stantec) has completed a Phase I Environmental Site Assessment

(ESA) report of the property located at Subarea 2 and Subarea 3 at the Port Gamble S’Klallam Tribe

(PGST) Tribal Community in Kingston, Washington (Subarea 2 and Subarea 3, or the “Subject Property”),

on behalf of PGST (the “Client”). The work was performed according to Stantec’s proposal and terms and

conditions dated December 1, 2023 and accepted by the Client on January 23, 2024. PGST (the “User”)

has been designated as the User of this report. The intended use of this Phase I ESA is to support an

Updated Master Plan for the Administrative Campus that focuses on planned improvements and land

uses.

The Phase I ESA was conducted in conformance with the requirements of ASTM International (ASTM)

Designation E1527-21, and All Appropriate Inquiries (AAI) as defined by the United States Environmental

Protection Agency (EPA) in Title 40 of the Code of Federal Regulations, Part 312 (40 CFR 312), except

as may have been modified by the scope of work, and terms and conditions, requested by the Client. Any

exceptions to, or deletions from, the ASTM or AAI practice are described in Section 2.3. The location of

the Subject Property is shown on Figure 1, and the layout of the Subject Property is shown on Figure 2.

Photographs taken during the site visit are provided in Appendix A.

The Subject Property is located on the PGST Tribal Community adjacent to the PGST Administrative

Campus and consists of two distinct areas referred to herein as “Subarea 2” and “Subarea 3.” Details for

each subarea are provided in the table below. At the time of the site visit, Subarea 2 contained the Little

Boston S’Klallam Indian Cemetery, a boat building education center, gravel covered parking areas and

vacant land. Subarea 3 contained a gravel covered day parking lot, storage for small equipment and

materials and a PGST potable water well house.

Kitsap County Tax

Parcel #

052702-1-001-2005

082702-1-001-2002

052702-4-005-2005

052702-1-001-2005

Report

Abbreviation

Subarea 2

Subarea 3

Address – Kingston, Washington

33453 Hood Canal Lane Northeast

6400 Northeast Bud Purser Lane

No situs

33453 Hood Canal Lane Northeast

Subarea

Size

2.7

1.2

Owner

United States of

America In Trust

Port Gamble /

S’Klallam

Although the Subject Property was the ancestral lands of PGST thousands of years before the European

settlers arrived, the present day PGST Tribal Community was established under the Indian

Reorganization Act of 1934 with 1,234-acres proclaimed for PGST use in 1938. Online records indicate

the earliest burial at the Little Boston S’Klallam Indian Cemetery (Subarea 2) was in 1857, although there

are likely earlier dates that were not recorded. In addition to the cemetery, Subarea 2 contained

residences and a boat building education center. The residences located on Subarea 2 were demolished

in July of 2023. Subarea 3 was undeveloped and forested through 1968 and by the 1980s had been

partially cleared and appeared to contain a small storage structure. Many of the existing storage

structures were visible on Subarea 3 by the mid-2000s.

Project No.: 2042681800

1.1

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Summary

April 25, 2024

The area to the east of Subarea 2 and west of Subarea 3 contains the PGST Administrative Campus. The

area to the north contains forested land including to the east of Subarea 3. A steep bluff adjoins Subarea

2 to the west followed by the shores of Port Gamble. To the south, the administrative campus is bordered

by forested land and scattered residences. Little Boston Road Northeast extends north along the east

border of Subarea 2 and then makes a dog leg to the east and adjoins the north border of Subarea 2

before continuing through the PGST Tribal Community. A Subject Property Location Map is illustrated on

Figure 1. A Subject Property Vicinity Map illustrating the main features of the Subject Property is provided

as Figure 2. Photographs taken during the site reconnaissance visit are provided in Appendix A.

We have performed a Phase I ESA in conformance with the scope and limitations of ASTM Practice

E1527-21 of Subarea 2 and Subarea 3 at the PGST Tribal Community in Kingston, Washington, or the

“Subject Property”. Any exceptions to, or deletions from, this practice are described in Section 2.3 of this

report. This assessment has revealed no recognized environmental conditions (RECs), Controlled RECs

(CRECs), or significant data gaps in connection with the Subject Property. No further investigation

appears to be warranted at this time.

The preceding summary is intended for informational purposes only. Reading of the full body of this report

is recommended.

Project No.: 2042681800

1.2

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Introduction

April 25, 2024

2.0

INTRODUCTION

The objective of this Phase I ESA was to perform AAI into the past ownership and uses of the Subject

Property consistent with good commercial or customary practice as outlined by the ASTM in “Standard

Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process”,

Designation E1527-21. AAI is the process for evaluating a property’s environmental conditions for the

purpose of qualifying for landowner liability protections under the Comprehensive Environmental

Response, Compensation, and Liability Act (CERCLA) following final rule of 40 CFR Part 312. The

purpose of this Phase I ESA was to identify, to the extent feasible, adverse environmental conditions

including RECs of the Subject Property.

The ASTM E1527-21 standard indicates that the purpose of the Phase I ESA is to identify RECs,

including historical recognized environmental conditions (HRECs), and controlled recognized

environmental conditions (CRECs) that may exist at a property. The term “recognized environmental

conditions” means the presence or likely presence of any hazardous substances or petroleum products

in, on, or at a property:

1. Due to any release to the environment;

2. Under conditions indicative of a release to the environment; or,

3. Under conditions that pose a material threat of a future release to the environment.

ASTM defines a “HREC” as a REC that has occurred in connection with a property but has been

addressed to the satisfaction of the applicable regulatory authority and meets current unrestricted use

criteria established by a regulatory authority, without subjecting the property to any required controls (e.g.,

property use restrictions, activity and use limitations, institutional controls, or engineering controls). Before

calling the past release a HREC, the environmental professional (EP) must determine whether the past

release is a REC when the current Phase I ESA is conducted (e.g., if there has been a change in the

regulations). If the EP considers the past release to be a REC at the time the Phase I ESA is conducted,

the condition shall be included in the conclusions section of the report as a REC.

ASTM defines a “CREC” as a REC resulting from a past release of hazardous substances or petroleum

products that has been addressed to the satisfaction of the applicable regulatory authority (e.g., as

evidenced by the issuance of a no further action letter or equivalent, or meeting risk-based criteria

established by regulatory authority), but with hazardous substances or petroleum products allowed to

remain in place subject to the implementation of required controls (e.g., property use restrictions, activity

and use limitations, institutional controls, or engineering controls).

As defined by ASTM, RECs can include hazardous substances or petroleum products present under

conditions in compliance with laws if that presence represents a material threat of future release. The

presence of hazardous substances or petroleum products is, however, not a REC if that presence is a de

minimis condition. De minimis conditions are minor occurrences of contamination that generally do not

present a material risk to human health and would not likely be subject to enforcement action if brought to

the attention of governmental agencies. ASTM also considers the potential for a business environmental

Project No.: 2042681800

2.3

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Introduction

April 25, 2024

risk (BER), defined as a risk which can have a material environmental or environmentally driven impact

on the business associated with the current or planned use of the Subject Property, not necessarily

limited to those environmental issues required to be investigated by the ASTM standard. Consideration of

BERs may involve addressing one or more ASTM non-scope considerations.

The scope of work conducted during this Phase I ESA consisted of a visual reconnaissance of the

Subject Property, interviews with key individuals, and review of reasonably ascertainable documents. The

scope of work did not include an assessment for environmental regulatory compliance of any facility ever

operated at the Subject Property (past or present), or sampling and analyzing of environmental media.

Stantec was not contracted to perform an independent evaluation of the purchase or lease price of the

Subject Property and its relationship to current fair market value. The conclusions presented in this Phase

I ESA report are professional opinions based on data described herein. The opinions are subject to the

limitations described in Section 2.3.

ASTM E1527-21 notes that the availability of record information varies from source to source. The User or

EP is not obligated to identify, obtain, or review every possible source that might exist with respect to a

property. Instead, ASTM identifies record information that is reasonably ascertainable from standard

sources. “Reasonably ascertainable” means:

1. Information that is publicly available;

2. Information that is obtainable from its source within reasonable time and cost constraints; and,

3. Information that is practicably reviewable.

2.1

SUBJECT PROPERTY DESCRIPTION

The Subject Property consists of two distinct areas referred to herein as “Subarea 2” and “Subarea 3.”

Details for each Subarea are provided in the table below. At the time of the site visit, Subarea 2 contained

the Little Boston S’Klallam Indian Cemetery, a boat building education center, gravel covered parking

areas and vacant land. Subarea 3 contained a gravel covered day parking lot, storage for small

equipment and materials and a PGST potable water well house.

Kitsap County Tax

Parcel #

052702-1-001-2005

082702-1-001-2002

052702-4-005-2005

052702-1-001-2005

Report

Abbreviation

Subarea 2

Subarea 3

Address – Kingston, Washington

33453 Hood Canal Lane Northeast

6400 Northeast Bud Purser Lane

No situs

33453 Hood Canal Lane Northeast

Subarea

Size

2.7

Owner

USA In Trust Port

Gamble / S'Klallam

1.2

Although the Subject Property was the ancestral lands of PGST thousands of years before the European

settlers arrived, the present day PGST Tribal Community was established under the Indian

Reorganization Act of 1934 with 1,234-acres proclaimed for PGST use in 1938. Online records indicate

the earliest burial at the Little Boston S’Klallam Indian Cemetery (Subarea 2) was in 1857, although there

are likely earlier dates that were not recorded. In addition to the cemetery, Subara 2 contained residences

and a boat building education center. The residences located on Subarea 2 were demolished in July of

Project No.: 2042681800

2.4

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Introduction

April 25, 2024

2023. Subarea 3 was undeveloped and forested through 1968 and by the 1980s had been partially

cleared and appeared to contain a small storage structure. Many of the existing storage structures were

visible on Subarea 3 by the mid-2000s.

The area to the east of Subarea 2 and west of Subarea 3 contains the PGST Administrative Campus. The

area to the north contains forested land including to the east of Subarea 3. A steep bluff adjoins Subarea

2 to the west followed by the shores of Port Gamble. To the south the administrative campus is bordered

by forested land and scattered residences. Little Boston Road Northeast extends north along the east

border of Subarea 2 and then makes a dog leg to the east and adjoins the north border of Subarea 2

before continuing through the PGST Tribal Community. A Subject Property and Vicinity Map is illustrated

on Figure 1. A Subject Property Layout Map illustrating the main features of the Subject Property is

provided as Figure 2. Photographs taken during the site reconnaissance visit are provided in Appendix

2.2

SPECIAL TERMS, CONDITIONS, AND ADDITIONAL

ASSUMPTIONS

It is assumed that the purpose of this Phase I ESA is to qualify the User for landowner protection from

CERCLA liability and to facilitate reuse or repurpose of the Subject Property. The possible contaminants

of concern considered in this assessment include those hazardous compounds listed under CERCLA and

petroleum products. There were no special terms, conditions, or significant assumptions associated with

the Phase I ESA.

2.3

EXCEPTIONS AND LIMITING CONDITIONS

This report documents work that was performed in accordance with generally accepted professional

standards at the time and location in which the services were provided and given the schedule and

budget constraints established by the client. No other representations, warranties, or guarantees are

made concerning the accuracy or completeness of the data or conclusions contained within this report,

including no assurance that this work has uncovered all potential and actual liabilities and conditions

associated with the Subject Property.

This report provides an evaluation of selected environmental conditions associated with the Subject

Property that was assessed at the time the work was conducted and is based on information obtained by

and/or provided to Stantec at that time. There are no assurances regarding the accuracy and

completeness of this information received from others.

Conclusions made within this report consist of Stantec’s professional opinion as of the time of the writing

of this report and are based solely on the scope of work described in the report, the limited data available,

and the results of the work. They are not a certification of the property’s environmental condition.

The client did not provide or contract Stantec to provide recorded title records or search results for

environmental liens or activity and use limitations encumbering the property or in connection with the

Subject Property. Stantec did not obtain historical records that document the Subject Property history in

Project No.: 2042681800

2.5

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Introduction

April 25, 2024

continuous 5-year intervals, and this resulted in data gaps. Based on the information obtained during the

course of this ESA and general knowledge of development at and near the Subject Property, the absence

of this information did not affect the ability of the EPs to identify RECs, HRECs, CRECs, or de minimis

conditions.

This report has been prepared for the exclusive use of the Client identified herein and any use of or

reliance on this report by any third party is prohibited, except as may be consented to in writing by

Stantec or as required by law. The provision of any such consent is at Stantec’s sole and unfettered

discretion and will only be authorized pursuant to the conditions of Stantec’s standard form reliance letter.

Stantec assumes no responsibility for losses, damages, liabilities, or claims, howsoever arising, from third

party use of this report.

As the purpose of this report is to identify Subject Property conditions which may pose an environmental

risk; the identification of non-environmental risks to structures or people on the Subject Property is

beyond the scope of this assessment.

The findings, observations, and conclusions expressed by Stantec in this report are not an opinion

concerning the compliance of any past or present owner or operator of the Subject Property which is the

subject of this report with any federal, state, or local law or regulation.

This report presents professional opinions and findings of a scientific and technical nature. It does not and

shall not be construed to offer a legal opinion or representations as to the requirements of, nor

compliance with, environmental laws, rules, regulations, or policies of federal, state, provincial or local

governmental agencies. It is recommended that issues raised by the report should be reviewed for the

client by its legal counsel.

Stantec specifically disclaims any responsibility to update the conclusions in this report if new or different

information later becomes available or if the conditions or activities on the Subject Property subsequently

change.

2.4

PERSONNEL QUALIFICATIONS

This Phase I ESA was conducted by, or under the supervision of, an individual that meets the ASTM

definition of an EP. The credentials of the EP and other key Stantec personnel involved in conducting this

Phase I ESA are provided in Appendix B.

Project No.: 2042681800

2.6

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 User-Provided Information

April 25, 2024

3.0

USER-PROVIDED INFORMATION

ASTM E1527-21 describes responsibilities of the User to complete certain tasks in connection with the

performance of AAI into the Subject Property. ASTM requires that the EP request information from the

User on the results of those tasks in the User Questionnaire, which is provided as Appendix C and

summarized below.

Description of Information

Description and/or Key Findings

User Questionnaire

The User Questionnaires were completed for each subarea by Ms. Abigail

Welch PGST Project Manager/Planner on March 11, 2024. Ms. Welch is not

aware of any current or historical chemical use, spills/releases, environmental

cleanups, or obvious indications of the presence of a release, or underground

storage tanks (USTs) at Subarea 2 or 3.

Environmental Liens or Activity

Use Limitations

Ms. Welch indicated that for Subarea 2, there was a 150 foot setback from the

Port Gamble shoreline and that no clearing or construction of impervious

surfaces was allowed without PGST Council approval; however, these

limitations do not appear to be related to environmental contamination,

investigation, or cleanup.

Ms. Welch does not have any knowledge of environmental liens or activity use

liens associated with Subarea 3.

Previous Environmental Reports

Ms. Welch indicated that an erosion and landslide hazard report was available

for Subarea 2. Due to the absence of environmental information contained in

such documents, Stantec did not review this report.

She was not aware of any environmental reports for Subarea 3.

Purpose of the Phase I ESA

The purpose of the Phase I ESA is to support an Updated Master Plan for the

Administrative Campus that focuses on planned improvements and land uses.

The User Questionnaire is included as Appendix C.

Project No.: 2042681800

3.1

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Records Review

April 25, 2024

4.0

RECORDS REVIEW

The objective of consulting historical sources of information is to develop the history of the Subject

Property and surrounding area and evaluate if past uses may have resulted in RECs. Physical setting

records are evaluated to determine if the physical setting may have contributed to adverse environmental

conditions in connection with the Subject Property. During the review of historical records, Stantec

attempted to identify uses of the Subject Property from the present to the first developed use of the

Subject Property. Stantec’s research included the reasonably ascertainable and useful records described

in this section.

4.1

PHYSICAL SETTING

A summary of the physical setting of the Subject Property in the following subsections is based on a

combination of information from Google Earth and the Washington Division of Geology and Earth

Resources.

4.1.1

Subject Property Topography and Surface Water Flow

The topography of Subarea 2 is generally flat with a gentle slope to the south. Google Earth indicates that

the elevation of Subarea 2 ranges between 76 feet above mean sea level (ft amsl) at the north end to 68

feet amsl to the south. A steep bluff adjoins the west boundary of Subarea 2 giving way to the shores of

Port Gamble. Subarea 3 is generally flat with an elevation ranging between 62 and 63 ft amsl. (Google

Earth Pro 2024).

4.1.2

Regional and Subject Property Geology

The geology of the Subject Property and site vicinity is mapped as “Pleistocene continental glacial drift”

deposits. This geologic unit is described as “till and outwash clay, silt, sand, gravel, cobbles, and boulders

deposited by or originating from continental glaciers; locally includes peat” (Schuster 2005).

Stantec completed a Phase II ESA for PGST at the Former Recirculating Gravel Filter Treatment Plant

located approximately 0.4 miles to the north of Subareas 2 and 3 as part of a United States

Environmental Protection Agency (EPA) brownfield grant (Stantec 2022). Based on this investigation the

subsurface consisted of sand with some silt.

4.1.3

Regional and Subject Property Hydrogeology

The shallow water table is often a subdued expression of surface topography. Shallow groundwater

generally flows from areas of groundwater recharge, such as hills and broad uplands, to areas of

groundwater discharge, such as wetlands, rivers, and lakes. Additionally, man-made features such as

wells, roads, filled areas, buried utility lines and sewers, and stormwater drainage systems may alter the

natural shallow groundwater flow direction. As such, the inferred shallow groundwater flow direction is to

Project No.: 2042681800

4.1

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Records Review

April 25, 2024

the west toward the shores of Port Gamble. During the Stantec 2022 Phase II ESA at the Former

Recirculating Gravel Filter Treatment Plant located 0.4 miles to the north of Subareas 2 and 3,

groundwater was encountered at a depth of 4.5 feet bgs.

4.2

FEDERAL, STATE AND TRIBAL ENVIRONMENTAL RECORDS

A regulatory agency database search report was obtained from Environmental Data Resources, Inc

(EDR) on March 11, 2024. A complete copy of the database search report is provided in Appendix D.

Stantec evaluated the information listed within the EDR report relative to potential impact to the Subject

Property, assessing the potential for impacts based in part on the physical setting. As part of this process,

inferences have been made regarding the likely groundwater flow direction at or near the Subject

Property. As described in Section 4.1.3, the inferred shallow groundwater flow direction is to the west.

Observations about the Subject Property and surrounding sites made during the site visit are provided in

more detail in Section 5.

4.2.1

Listings for Subject Property

The Subject Property (Subarea 3) was identified in the EDR database report. PGST is listed under the

Integrated Compliance Information System (ICIS), Facility Index System/Facility Registry System

(FINDS), Asbestos, and Enforcement and Compliance History Online (ECHO) databases. According to

the EPA’s ECHO database, PGST was required to address violations for their potable water systems

which included: failure to conduct required monitoring, report violations to their customers, and/or submit

reports to EPA Region 10. The PGST signed the Safe Drinking Water Act Administrative Orders on

Consent that EPA Region 10 proposed to them on May 18, 2011 (EPA n.d.). RECs were not identified for

the Subject Property in connection with this listing because the violations were corrected and resolved to

the satisfaction of the EPA. The Asbestos listing is related to the abatement of asbestos-containing

materials during the demolition of the former residences. RECs were not identified in connection with the

asbestos abatement.

4.2.2

Listings for Nearby Sites with Potential to Impact Subject Property

Stantec assessed data presented in the environmental agency database search report to evaluate the

potential for conditions on adjacent and nearby sites to pose a REC, CREC, or HREC for the Subject

Property. The evaluation included consideration of the potential for contamination by hazardous

substances or petroleum products to migrate to the Subject Property from a nearby site, including by

vapor migration or encroachment (i.e., potential for a vapor encroachment condition [VEC]). Based on this

evaluation, the sites listed in the table below were identified as the most likely potential sources of impact

to the Subject Property.

Based on distance, type of database listings, and/or the topographic gradient/inferred groundwater flow

direction, RECs were not identified in connection with the sites listed in the EDR Report provided in

Appendix D, including orphan sites (those with insufficient address information).

Project No.: 2042681800

4.2

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Records Review

April 25, 2024

4.3

LOCAL/REGIONAL ENVIRONMENTAL RECORDS

Stantec checked the following sources to obtain information pertaining to Subject Property use and/or

indications of RECs in connection with the Subject Property.

4.3.1

Port Game S’Klallam Tribe

Agency Name

Contact Date

PGST Planning Department

March 12, 2024

4.4

Finding

Mr. Rory McLeod of the PGST Planning Department indicated that

PGST has no records or evidence of storage tanks on the campus. In

addition, they do not have any records of environmental violations on

the PGST reservation. Mr. McLeod provided a map that showed the

location of 18 septic tanks located on the PGST campus, between

Subareas 2 and 3. Based on the use of the buildings served by these

septic systems for office, recreational purposes, and a dental clinic

(which typically have filters for mercury and other dental wastes) the

presence of the septic systems is not considered a REC. PGST also

provided Street Construction and Reconstruction Plans for the

campus – no RECs were identified in connection with the provided

records. PGST provided records are included in Appendix E.

HISTORICAL RECORDS REVIEW

4.4.1

Land Title Records/Deeds

Deeds, environmental liens, and activity and use limitation documentation was not provided by the User,

and public records were not searched by Stantec.

4.4.2

Aerial Photographs

Stantec reviewed historical aerial photographs provided by EDR for the years 1941, 1951, 1968, 1981,

1990, 2006, 2001, 2015 and 2019, which are included in Appendix F. The general type of activity on a

property and land use changes can often be discerned from the type and layout of structures visible in the

photographs. However, specific elements of a facility's operation usually cannot be discerned from aerial

photographs alone. The following table summarizes Stantec’s observations of the reviewed historical

aerial photographs:

Year(s)

Key Observations

1941

Subject Property: The north portion of Subarea 2 appears to be forested and the south developed

with two apparent small structures. Little Boston Road Northeast borders Subarea 2 to the west.

Subarea 3 appears to be partially forested; the south portion appears developed with a light

colored road or trail extending through it. Little Boston Road Northeast borders Subarea 3 to the

north.

Adjoining Sites: The area between Subarea 2 and 3 is partially forested, with at least five small,

shaped structures. The area south of Subara 2 appears to contain several small, square shaped

structures, on the west side of Little Boston Road Northeast with views of Port Gamble to the west.

Project No.: 2042681800

4.3

PHASE I ENVIRONMENTAL SITE ASSESSMENT

PORT GAMBLE S'KLALLAM TRIBE SUBAREA 2 AND 3, KINGSTON, WASHINGTON

Subarea 2 and 3 Records Review

April 25, 2024

1951, 1968

Subject Property: Subarea 2 appears to be partially forested; several new structures appear to

have been constructed in the south portion of Subarea 2.

Subarea 3 appears similar to the 1941 aerial photograph.

Adjoining Sites: Several new structures are visible in the area between Subareas 2 and 3. No other

significant changes were observed.

1981

Subject Property: Subareas 2 and 3 appear similar to the 1968 aerial photograph, except for a

new, small outbuilding located on the east portion of Subarea 3.

Adjoining Sites: Two large buildings and several smaller structures appear to have been

constructed in the area of the present day PGST administrative campus. A baseball field was

constructed to the southeast of Subarea 3.

1990

Subject Property: No significant changes were observed to Subareas 2 and 3 from the 1981 aerial

photograph.

Adjoining Sites: The main building located on the PGST administrative campus appears to have

been enhanced or enlarged.

2006

Subject Property: No significant changes were observed to Subareas 2 and 3 from the 1990 aerial

photograph.

Adjoining Sites: The PGST administrative campus (located between Subareas 2 and 3) appears

similar to the present day.

2011, 2015

Subject Property: No significant changes were observed to Subarea 2.

Subarea 3 appears to be utilized as a parking lot, with several parked automobiles visible on the

aerial photograph. A total of three structures was observed in the northeast corner of Subarea 3.

Adjoining Sites: The PGST administrative campus (located between Subarea 2 and 3) appears

similar to the present day.

2019

Subject Property: No significant changes were observed to Subarea 2.

A total of seven structures (including trailers) appears on the north portion of Subarea 3.

Adjoining Sites: No significant changes were observed.

No RECs were noted during the review of the historical aerial photographs.

4.4.3

City Directories

Stantec reviewed reverse city directories provided by EDR for the years 1987, 1992, 1995, 2000, 2005,

2010, 2014, 2017 and 2020, which are included in Appendix F. Listings for the Subject Property are

summarized below.

Subject Property

Subject Property, Subarea 2

31973 Little Boston Road

Northeast

Subject Property, Subarea 2

31941 Little Boston Road

Northeast

Subject Property, Subarea 2

31925 Little Boston Road

Northeast

Project No.: 2042681800

Year

2020, 2017

2014, 2010,

2005

2020, 2017,

2014, 2010,

2005

2020, 2017

2014

Listed Occupants

No listings

Residential

Busters Ice Cream /Residential

No listings

Residential

4.4

PHASE I ENVIRONMENTAL SITE ASSES

This text is long and has been trimmed here. Open the source document for the complete record.

This is a copy of a public record, reproduced as it was published. It is not legal advice, and it may not be the version a court would rely on. Check the official source before you cite it.