Report .
e V E�y Pietrok Engineering&Resources
RECE
OCT 2 2020 �$ grrnp 0 C3
CITY OF TIGARD u, ,
BUILDING DIVISION
OFFICE COPY
DRAINAGE REPORT FOR
CRESCENT GROVE CEMETERY
ADMINISTRATION BUILDING
9925 SW GREENBURG ROAD
TIGARD, OREGON 97223
Date: 10.23.2020
Author: Neil Pietrok, PE
Pietrok Engineering and Resources
Page 1 11
166
Pietrok Engineering&Resources
PROJECT SUMMARY:
The following is the storm water report for the new Administration Building at the Crescent
Grove Cemetery at 9925 SW Greenburg Road, Tigard, Oregon. The new building footprint is
4,552 square feet. The new associated impervious surfaces including walkways, curbs and
stairs is equal to 1,293 square feet. The building and new walks will remove an existing 1 ,454
square feet of impervious surface.
Per CWS R&O 19-5, Section 2.04.2.d.4, New and Existing Impervious Square Footage
A) Within Public Right-of-Way = 0 sf
B) Within Private Right-of-Way = 0 sf
C) On Private Property:
a. Buildings (existing) = 1306 sf
b. Buildings (new) = 4,552 sf
c. Walkways, curbs, pavement, etc. (existing) = 148 sf
d. Walkways, curbs, etc. (new) = 1,293 sf
e. Percent increase in impervious area for entire cemetery property 0.04%
The following codes, regulations, and rules were used in preparation of this report:
• Clean Water Services Design and Construction Standards R&O 19-5 for Sanitary and
Surface Water Management, April 2019:
o Chapter 4 Runoff Treatment Control
o Chapter 5 Conveyance Design
o Chapter 6 Erosion Control
o Appendix B Standard Details
• Clean Water Services Low Impact Development Approches (LIDA) Handbook 2016
REPORT FORMAT:
Per CWS R&O 19-5, Section 2.04.2.m. this report has the following sections:
A) Maps with drainage basin, contours, and site plan with the development layout
and stormwater facilities.
B) Calculations for the water quality facility.
C) Review of downstream conveyance system.
D) Hydromodification assessment
E) Narrative of water quality facilities.
MAPS:
• See appendix A for the basin maps with contours. The northwest corner of the
property is the highpoint in the surrounding basin. No water runoff runs onto the
site. The location of the new stormwater facilities will be west of the new building
2 1i
•
(60
ej
Pietrok Engineering&Resources
and part of the new building foundation. The facility west of the building only
collects water immediately in the area of the facility and the planter in the
foundation will only collect runoff from the roof of the facility.
o The downstream analysis was previously completed by the existing
stormwater facility to the north of the Administration Building Site. The new
rain garden will not increase the outflows and will connect into the piping for
this existing facility.
• Sheet C.3 of the design plans show the storm water system including the water
quality facilities. This sheet has been included in Appendix B.
CALCULATIONS:
• Per CWS R&O 19-5, Section 4.03.d: With a total new impervious surface of less
than 12,000 square (4,552 SF building footprint + 1,293 SF new walkways +
1,454 replaced surface) and the project being in Hydromod Category 1 , the
owner may elect to pay the fee-in-lieu for reduction of downstream impacts.
o The fee-in-lieu is $1.00 x 7,299 square feet = $7,229.00
• Storm Water Quality Facility Calculations:
o Per Section 4.08.1 .d: Stormwater Management Area = new impervious
surface + (3 x modified impervious surface - permanently removed).
=> ((4552+145+1148+1050-(1306+148) + (3x(1306+148) = 9,803 sf
Per Section 4.08.4 simplified sizing, b.: a 6% sizing factor shall be used to
calculate the water quality surface area.
The east half of the roof will drain to a stormwater planter per LIDA detail
724, 6% x 2,276 = 137 sf.
The remaining area will drain to the infiltration planter.
6% x (9,803-2,276) sf = 452 sf
REVIEW OF DOWNSTREAM CONVEYANCE SYSTEM
The downstream analysis for this site was previously completed by the installation of the
existing stormwater planter to the north of the new Administration Building. The new
facilities will drain into the piping for this facility and will not increase the flows off of the
site.
Page 3111
sollis,„„:1
m
V 2
Pietrok Engineering&Resources
HYDROMODIFICATION ASSESSMENT
Using the CWS Hydromodification map tool, the site was outside of the
hydromodification risk areas. Based on Table 4-2 (CWS R&O 19-5, Section 4.03.5) the
site is development Class/risk level=Developed/Low; Category 1.
NARRATIVE OF WATER QUALITY FACILITIES
The new Administration Building will result in 5,845 square feet of impervious surface. A LIDA
planter and a LIDA swale with an underdrain are proposed to treat water quality. The new
LIDA planter will have an area of 137 square feet. The new LIDA swale will have an area
greater than 452 square feet. The LIDA planter and swale are a LIDA structure. The site is
outside the hydromodification risk area.
' 4 1I
v
Pietrok Engineering&Resources
---Sw Summit Dr _"` '' �..411ir., " p��
L , ifffi „IR.. wilL
■
„ 0 iii iiir3.ill
ii
sir, i .
1I --J Crescent Gjrove Cemetery,North Entr,41 i gli
`o ; SW Lehmann St S
Crescent Grave m �} �® s.
' c Cemmetery JJC� V, 1 11° 10 3�1° cn -/ t nil
3 .. it
; � I ■t1 _-' = Crescent Grove Cemetery Middle Ent, 1J
11111mu
> ;> CoratDO 0
I
.__.� Crescent Grove Cgmetary South Envd ���
SW Washington Square Rd F.--1
__ 1:3 0
6 Ill
t �
SW Washington Square Rd Gar)Cle
rxeui i tt}
n
r
V
Figure 1: Basin Map: note the highpoint in the northwest corner of the property.
I' ae, e 611]
l 'ilT I. L
CRESCENT GROVE
CEMETERY ADMIN BLDG.
9925 SW GREENRURC RD.
i / �,; 11GARD.OR 97223
tt \ / - SEMI/WATER MANAGEMENT
� . PI AN NARRATIYF
COWED'TO EXISTING
I
IPERNWS SIIREALES'
SIIIAY LW[M RR k' -j Etl5PN6 TO RE REMOVED(MDJIRH)
E-R26.W r = n ... _. • (E)WALKWAYS
ROOF•1306 Y
FEW WREN MPH NU ,,, ..eY •NEW
WALKWAYS-N W SF
I IDGIxM •, . (II)ROOF-4552 Sr
wwuwxwwwwwwnryywmann0l.. ..i.4........�. / • N)BACK PAID-145 SF
o, r www �.. ..... wwwxemww . P /
•
W swot FT/FT w,—� —. µ �' ww�wxa • INN)FRONT AREA-1 LIT SF ]
FWi=Y[TM lu BORE PITS AT 100 SF EACH 700
i SF%1.5-1050 SF
DARN cmWa ;� SANITARY FM 1]6[CE STOW PPE/
W: R )PER
NIEiROC'Mu RE N�IOMS 1I �_ __ b0.01 M 01 _ 19-5(MINDED BY R60 19-11).
RN VW 227.M i E=�23.00 NMI W2 M- O O CHAPTER 1.
r WEND STORM uxE O O THIS SITE IS NOT LOCATED IN A
O // — - 01114rA1FR PUNKA ____ Q xYLAW COmCAnoN AREA
A]Y PER SECTION 408121
11
f _ / / Q Q 0 S10HMWATER MANAGEMENT AREA-
NEW IMPERVIOUS SURFACE!(]M
MODIFIED IMPERVIOUS SURFACE-
0 00 oV PERMANENTLY REMOVED)
I �O 0 "
0 O 0 PER SECTON 4034 SWIPEO SIZING,
xEx ULR PAR GUSfN I 0 0Q T06e SANG CµCULATEATHE WATER QUALITY USERCTOR SHALL IIE
BON IN UF�V53M Bl /
( ]Q 'AP O SURFACE AREA
DETAIL 721.
AREA 152 S I _ I .� 1 PHIEER EAST HALF OF THE ROOF MIL
I / GRAIN TO A STORMY/ATER PLANTER
• • • III/ Si X
•
WE
G AREA
♦ • ♦• % 5 2R9Ta-1276)SF RSM-R N
• • •
LL
• ••••{y / OrAL 5 CMN1101flEN AND O, LLAIN l0
- • • _ H E INFILTRATOR'LINTER. Z
T BE
F I II �. x00 �,R SF
xA
1. / 5111RMWAlER.
•�• �S'� - —•
SEE ENLARGED]ITE PLAN AT LEFT
• — C? FOR LOCATIONS.
II -
••eAN • II I — I/ IrmaF
ENGINEERING
NO RESOURCES
13
I
I I — PW 6"`NMvaxi6w
❑ acx.-a�rr
I
AIA ARCHITECTS
1 I ,I ',r1 ,, — PERMIT SET
4 r , _ �.�. QI 0 - _ gM1NW TILE
4 II I I _ STORMWATER PLAN
II r — DRAWS REVISIONS
Il
�� �
I I IiII I -
.a m I II I] a ❑III a / DRAWING NO
n C.3
OSTORM WAIER PLAN
`J 6 W>WR�'
1 seNE ,.-IG•-Lr WR NR11904
GATE OCT.21.'MM SCALE AS NI11F0
CRESCENT GLE)K fL¢LFRT NRM RIRG
Flow-Through Planter Operation and Maintenance Plan
i' Annual inspections are required. It is recommended that the facility is inspected on a monthly basis to ensure proper function.The plan below describes
inspection and maintenance activities, and may be used as an inspection log. Contact the design engineer, Clean Water Services or City representative for
z more information.
a
Identified Problem Condition to Check for Maintenance Activity Maintenance Timing ✓ Task Complete Comments
Sediment Accumulation in Sediment depth exceeds 3 inches Remove sediment from treatment ,
Treatment Area area. Ensure planter is level from
side to side and drains freely toward SUMMER FALL
outlet;no standing water within 24
hours after any major storm (1-inch in Ideally in dry season
24 hours)
r
O
Erosion Erosion or channelization that impacts Repair eroded areas and stabilized <'
0 or effects the function of the facility or using proper erosion control mea-
n
0
creates a safety concern sures Establish appropriate vegetation FALL WINTER SPRING
CD
as needed Inspect after major storm
o (1-inch in 24 hours)
3
CD
-a Standing Water Standing water in the planter between Remove sediment or trash blockages.
3 storms that does not drain freely. Grade out areas of mounding and
0 Water should drain after 24 hours of improve end to end grade so there is t �.,.
dry weather. no standing water. WINTER SPRING
=
cu
Q
o Flow Not Distributed Flow unevenly distributed through Level the spreader and clean sokie
7- Evenly planter width due to uneven or that flows spread evenly over entire �+ ,tdt
clogged flow spreader planter width WINTER SPRING
:v
Obstructed Inlet/Outlet Material such as vegetation,sediment, Remove blockages from facility "'
trash is blocking more than 10%of
the inlet/outlet pipe WINTER SPRING
Inspect after major storm
(1-inch in 24 hours)
Flow-Through Planter Operation and Maintenance Plan (continued)
Annual inspections are required. It is recommended that the facility is inspected on a monthly basis to ensure proper function.The plan below describes
inspection and maintenance activities, and may be used as an inspection log. Contact the design engineer, Clean Water Services or City representative for
more information.
Identified Problem Condition to Check for Maintenance Activity Maintenance Timing V Task Complete Comments
Poor Vegetation Coverage 80% survival of approved vegetation Determine cause of poor growth and
and no bare areas large enough to correct the condition;replant with
affect function of facility. plugs or containerized plants per ap SPRING FALL
proved plans and applicable standards Ideal time to plant is spring and
at time of construction.Remove ex- fall seasons
cessive weeds and all invasive plants.
Invasive Vegetation as Invasive vegetation found in facility. Remove excessive weeds and all
outlined in Appendix A Examples include:Himalayan Blackber- invasive plants.Attempt to control
ry;Reed Canary Grass;Teasel, even if complete eradication is not SPRING SUMMER FALL
English Ivy, Nightshade,Clematis, feasible.Refer to Clean Water Services
Cattail,Thistle Integrated Pest Management Plan for
ra
appropriate control methods,includ-
= ing proper use of chemical treatment.
0
Excessive Vegetation Vegetation grows so tall it competes Prune over-hanging limbs,if possible;
with or shades approved emergent remove brushy vegetation as needed. SPRING
wetland grass/shrubs;interferes with Prune emergent wetland grass/shrubs Ideal time to prune emergent
access or becomes a fire danger that have become overgrown. wetland grass is spring
Vector Control Evidence of rodents or water flowing Repair damage to facility. Remove As Needed
through facility via rodent holes.Harm- harmful insects,call professional if
ful insects such as wasps or hornets needed.Refer to Clean Water Services
present Integrated Pest Management Plan for
management options.
o
Flow-Through Planter Operation and Maintenance Plan (continued)
k Annual inspections are required. It is recommended that the facility is inspected on a monthly basis to ensure proper function.The plan below describes
�s' inspection and maintenance activities, and may be used as an inspection log. Contact the design engineer, Clean Water Services or City representative for
more information.
m
Identified Problem Condition to Check for Maintenance Activity Maintenance Timing ✓Task Complete Comments
Trash and Debris Visual evidence of trash, debris or Remove and dispose of trash and debris V
dumping. from facility.Dispose of properly
SPRING SUMMER FALL WINTER
Contamination and Evidence of oil,gasoline,contaminants, If contaminants or pollutants present,
0 Pollution or other pollutants.Look for sheens, coordinate removal/cleanup with local
odor or signs of contamination. jurisdiction. SPRING SUMMER FALL WINTER
n
Outlet Structure Damaged Grate or overflow structure is missing Repair or replace outlet structure. As Needed
or only partially in place and may
72, have missing or broken grate members.
a
0
a
C
In
Q
0
O
O
tO
to
LIDA Swale Operation and Maintenance Plan
Annual inspections are required. It is recommended that the facility is inspected on a monthly basis to ensure proper function.The plan below describes
inspection and maintenance activities, and may be used as an inspection log. Contact the design engineer, Clean Water Services or City representative for
more information.
Identified Problem Condition to Check for Maintenance Activity Maintenance Timing ✓Task Complete Comments
Sediment Accumulation in Sediment depth exceeds 3 inches Remove sediment deposits in
Treatment Area treatment area.Swale should be level
from side to side and drain freely SUMMER FALL
0 toward outlet Ideally in Dry Season
Standing Water Standing water in the swale between Remove sediment or trash blockages;
storms that does not drain freely improve grade from end to end of
ro
swale;no standing water 24 hours WINTER SPRING
after any major storm(1 inch in 24 Inspect after any major storm
CD hours) (1-inch in 24 hours)
r-.
Flow Not Distributed Flows unevenly distributed through Level the spreader and dean so that As Needed
Evenly swale due to uneven or clogged flow flows spread evenly over entire swale
spreader width
0_ Poor Vegetation Coverage 80%survival of approved vegetation Determine cause of poor growth
o and no bare areas large enough to and correct the condition; replant 74—
affect function of facility with plugs or containerized plants FALL SPRING
per approved plans and applicable
standards at time of construction. Ideal time to plant is Spring and
Remove excessive weeds and all Fall seasons
invasive plants.
Excessive Vegetation Vegetation grows so tall it competes Prune overhanging limbs if possible.
n with or shades approved emergent Prune emergent wetland grass/shrubs
wetland grass/shrubs;interferes with that have become overgrown SPRING
access or becomes a fire danger Ideal time to prune emergent
wetland grass is Spring
>n
LIDA Swale Operation and Maintenance Plan (continued)
Annual inspections are required. It is recommended that the facility is inspected on a monthly basis to ensure proper function.The plan below describes
inspection and maintenance activities, and may be used as an inspection log. Contact the design engineer, Clean Water Services or City representative for
more information.
Identified Problem Condition to Check for Maintenance Activity Maintenance Timing i/Task Complete Comments
Invasive Vegetation as Invasive vegetation found in facility. Remove excessive weeds and all *•"
outlined in Appendix A Reed Canary Grass;Teasel,English Ivy; invasive plants.Attempt to control
Nightshade;Clematis;Cattail,Thistle; even if complete eradication is not SPRING SUMMER FAEI
Scotch Broom feasible.Refer to Clean Water Services
Integrated Pest Management Plan for
appropriate control methods,including
proper use of chemical treatment
Observed dead,dying or diseased trees
Hazard Trees Remove hazard trees.A certified As Needed
arborist may need to determine health
c of tree or removal requirements
-a
1
15
Material such as vegetation,sediment
Obstructed Inlet/Outlet or debris is blocking more than 10% Remove blockages from facility
of the inlet/outlet pipe
0
WINTER SPRING
ro
Inspect after any major storm
(1-inch in 24 hours)
oOutlet structure damage may include
Damage to Outlet Structure a grate that is missing or not in place. Grate must be in place and meet As Needed
Grate may have broken members or design standards. Replace or repair
have a damaged frame grate and ensure grate is firmly
attached
Erosion or channelization that impacts
Erosion or effects the function of the facility or Repair eroded areas and stabilized
creates a safety concern using proper erosion control
measures.Establish appropriate FALL WINTER SPRING
vegetation as needed
Evidence of trash,debris or dumping
0
LIDA Swale Operation and Maintenance Plan (continued)
Annual inspections are required. It is recommended that the facility is inspected on a monthly basis to ensure proper function.The plan below describes
inspection and maintenance activities, and may be used as an inspection log. Contact the design engineer, Clean Water Services or City representative for
more information.
Identified Problem Condition to Check for Maintenance Activity Maintenance Timing ✓ Task Complete Comments
Trash and Debris Remove trash and debris from facility. 40
Dispose of properly
SPRING SUMMER FALL WINTER
0
Contamination and Evidence of oil gasoline,contaminants, Locate source of contamination and
v Pollution or other pollutants. Look for sheens, correct.Remove oil using oil-absorbent
odor or other signs of contamination pads or vactor truck.If low levels of SPRING SLIMMER FAL I WINTER
CD
oil persist plant wetland plants that
can uptake small concentrations of oil
such as Juncus effuses.(soft rush) If
ro
high levels of contaminants or pollutants
are present,coordinate removal/
cleanup with local jurisdiction
ro
Vector Control General evidence of rodents or water Repair facility if damaged.Remove As Needed
piping through facility via rodent harmful insects,use professional if
o holes. Insects such as wasps and needed.
7S- hornets interfere with maintenance/ Refer to Clean Water Services
inspection activities Integrated Pest Management Plan for
management options
Damage to Outlet Structure Damage to Frame or Top Slab.Frame Ensure frame is firmly attached and As Needed
not sitting flush on top slab(more sits flush on the riser rings or top slab
than 3/n inch between frame and top
slab);frame not securely attached
y. Damage to Outlet Structure Fractures or Cracks in Walls or Bottom. Structure replaced or repaired to As Needed
Maintenance person determines the design standards
structure is unsound.Soil entering
structure through cracks
After Recording Return to:
Clean Water Services
2550 SW Hillsboro Hwy.
Hillsboro, OR 97123
PRIVATE STORMWATER FACILITIES
AGREEMENT
This Agreement is made and entered into this day of 20 ,by and between Clean Water Services
(District)and (Owner)whose address is
RECITALS
A. Owner has developed or will develop the Facilities listed below. (List the type of private stormwater facilities on
site and the quantity of each type).
Facility type(list each) Quantity
B. The Facilities enable development of property while mitigating the impacts of additional surface water and
pollutants associated with stormwater runoff prior to discharge from the property to the public stormwater system.
The consideration for this Agreement is connection to the public stormwater system.
C. The property benefited by the Facilities and subject to the obligation of this Agreement is described below or in
Exhibit A(Property)attached hereto and incorporated by reference.
D. The Facilities are designed by a registered professional engineer to accommodate the anticipated volume of
runoff and to detain and treat runoff in accordance with District's Design and Construction Standards.
E. Failure to inspect and maintain the Facilities can result in an unacceptable impact to the public stormwater system.
Page 1 of 3—Private Stormwater Facility Agreement
NOW, THEREFORE,it is agreed by and between the parties as follows:
1. OWNER INSPECTIONS District shall provide Owner an Operations and Maintenance Plan(O&M Plan)for
each Facility. Owner agrees to operate, inspect and maintain each Facility in accordance with the current O&M Plan
and any subsequent modifications to the Plan. Owner shall maintain a log of inspection activities. The log shall be
available to District upon request or during District inspections.
2. DEFICIENCIES All aspects in which the Facilities fail to satisfy the O&M Plan shall be noted as
"Deficiencies".
3. OWNER CORRECTIONS All Deficiencies shall be corrected at Owner's expense within thirty(30)days after
completion of the inspection. If more than 30 days is reasonably needed to correct a Deficiency, Owner shall have a
reasonable period to correct the Deficiency so long as the correction is commenced within the 30-day period and is
diligently prosecuted to completion.
4. DISTRICT INSPECTIONS Owner grants District the right to inspect the Facilities. District will endeavor to
give ten(10) days prior written notice to Owner, except that no notice shall be required in case of an emergency.
District shall determine whether Deficiencies need to be corrected. Owner(at the address provided in this Agreement,
or such other address as Owner may designate in writing to District)will be notified in writing through the US Mail of
the Deficiencies and shall make corrections within 30 days of the date of the notice.
5. DISTRICT CORRECTIONS If correction of all Owner or District identified Deficiencies is not completed
within thirty(30) days after Owner's inspection or District notice, District shall have the right to have any
Deficiencies corrected. District(i) shall have access to the Facilities for the purpose of correcting such Deficiencies
and(ii) shall bill Owner for all costs reasonably incurred by District for work performed to correct the Deficiencies
(District Correction Costs) following Owner's failure to correct any Deficiencies in the Facilities. Owner shall pay
District the District Correction Costs within thirty(30)days of the date of the invoice. Owner understands and agrees
that upon non-payment, District Correction Costs shall be secured by a lien on the Property for the District Correction
Cost amount plus interest and penalties.
6. EMERGENCY MEASURES If at any time District reasonably determines that the Facilities create any
imminent threat to public health, safety or welfare, District may immediately and without prior notice to Owner take
measures reasonably designed to remedy the threat. District shall provide notice of the threat and the measures taken
to Owner as soon as reasonably practicable, and charge Owner for the cost of these corrective measures.
7. FORCE AND EFFECT This Agreement has the same force and effect as any deed covenant running with the
land and shall a h be
nefit beefit and
d bind all owners of the Property present and future, and their heirs, successors and assigns.
8. AMENDMENTS The terms of this Agreement maybe amended only by mutual agreement of the parties. Any
amendments shall be in writing, shall refer specifically to this Agreement, and shall be valid only when executed by
the owners of the Property, District and recorded in the Official Records of the county where the Property is located.
9. PREVAILING PARTY In any action brought by either party to enforce the terms of this Agreement,the
prevailing party shall be entitled to recover all costs, including reasonable attorney's fees as may be determined by the
court having jurisdiction,including any appeal.
10. SEVERABILITY The invalidity of any section, clause, sentence, or provision of this Agreement shall not
affect the validity of any other part of this Agreement,which can be given effect without such invalid part or parts.
Page 2 of 3—Private Stormwater Facility Agreement
IN WITNESS WHEREOF, Owner and District have signed this Agreement.
NOTARIZE DOCUMENT BELOW
INDIVIDUAL OWNERS SIGN BELOW CORPORATE, LLC, PARTNERSHIP, TRUST OR OTHER
LEGAL ENTITY SIGN BELOW
Owner(Individual)
(Entity name)
Owner(Individual)
By: 1
(Sign here for entity)
Title:
CLEAN WATER SERVICES APPROVED AS TO FORM
By:
General Manager or Designee District Counsel
[Use this notary block if OWNER is an individual.]
STATE OF )
)
County of )
This instrument was acknowledged before me this day of , 20 ,
by
Notary Public
[Use this notary block if OWNER is an entity.]
STATE OF )
)
County of )
This instrument was acknowledged before me on (date)
by (name of person) as
(tide) of (name of entity).
Notary Public
Page 3 of 3—Private Stormwater Facility Agreement
Carlson Geotechnical Bend Office (541) 330-9155 C7Q'�LSo�L
Eugene Office (541) 345-0289
A division of Carlson Testing, Inc. Salem Office 503 589-1252
Phone: (503)601-8250 ( ) GEOTECHNICAL
Tigard Office (503) 684-3460
www.carlsontestinq.com
Updated Geotechnical Report
Crescent Grove Cemetery Administration Building
9925 SW Greenburg Road
Tigard, Oregon
CGT Project Number G2005381
Prepared for
Nancy Felton
Crescent Grove Cemetery
9925 SW Greenburg Road
Tigard, Oregon 97223
October 27, 2020
Office: 18270 SW Boones Ferry Road, Suite 6, Durham, Oregon 97224
Mailing: P.O. Box 230997,Tigard, Oregon 97281
Carlson Geotechnical Bend Office (541)330-9155 p►R�- O •
Eugene Office (541)345-0289 G
A division of Carlson Testing, Inc. Salem Office (503)589-1252 GEOTECHNICAL
Phone: (503)601 8250 Tigard Office (503)684-3460
wvAu_c:arlsontet,nq L.om
October 27, 2020
Nancy Felton
Crescent Grove Cemetery
9925 SW Greenburg Road
Tigard, Oregon 97223
Updated Geotechnical Report
Crescent Grove Cemetery Administration Building
9925 SW Greenburg Road
Tigard, Oregon
CGT Project Number G2005381
Dear Ms. Felton:
Carlson Geotechnical (CGT), a division of Carlson Testing, Inc. (CTI), is pleased to submit this updated
geotechnical report for the proposed Crescent Grove Cemetery Administration Building project. The site is
located at 9925 SW Greenburg Road in Tigard, Oregon. We performed our work in general accordance with
CGT Proposal GP9138R1, dated October 14, 2020. Written authorization for our services was received on
October 14, 2020.
We appreciate the opportunity to work with you on this project. Please contact us at (503) 601-8250 if you
have any questions regarding this report.
Respectfully Submitted,
CARLSON GEOTECHNICAL
tik,.q PR Opt,
C9��~ tG�GtN�`,pU'D
7077 2 Er r
OREGON
,p/. 1 CP9O�on 10, 2Q��`yfvP�
:„.11,27
EXPIRES: 401 /20.-2-
Morgan Masley, EIT Brad M. Wilcox, P.E., G.E.
Geotechnical Staff II Principal Geotechnical Engineer
mmasley(c�carlsantestinq.com bwilcox(a�carisontestinq.com
Doc ID: G\GEOTECH\PROJECTS\2020 Projects\G2005381 - Crescent Grove Cemetry Building - Updated Geotechnical Report1008-
Deliverables\Report\G2005381 Updated Geotechnical.docx
Office: 18270 SW Boones Ferry Road,Suite 6, Durham, Oregon 97224
Mailing: P.O. Box 230997,Tigard, Oregon 97281
Crescent Grove Cemetery Administration Building
Tigard, Oregon
CGT Project Number G2005381
October 27, 2020
TABLE OF CONTENTS
1.0 INTRODUCTION 4
1.1 Project Information 4
1.2 Scope of Services 4
2.0 SITE SURFACE CONDITIONS 4
3.0 SUBSURFACE CONDITIONS 5
4.0 CONCLUSIONS 5
5.0 UPDATED RECOMMENDATIONS 6
5.1 Seismic Site Class 6
5.2 Seismic Design 6
6.0 LIMITATIONS & CLOSURE 6
ATTACHMENTS
Site Plan Figure 1
Site Photographs Figure 2
Reproduced 2006 Test Pit Logs Appendix A
Carlson Geotechnical Page 3 of 6
Crescent Grove Cemetery Administration Building
Tigard, Oregon
CGT Project Number G2005381
October 27, 2020
1.0 INTRODUCTION
Carlson Geotechnical (CGT), a division of Carlson Testing, Inc. (CTI), is pleased to submit this updated
geotechnical report for the proposed Crescent Grove Cemetery Administration Building project. The site is
located at 9925 SW Greenburg Road in Tigard, Oregon.
1.1 Project Information
CGT previously performed a geotechnical investigation for a previous project at the Cemetery, the results of
which were presented in our report titled "Preliminary Geotechnical Investigation," dated September 27, 2006
(CGT Project Number G0602906). A PDF copy of that report was recently conveyed to us by Giulietti /
Schouten AIA Architects (GSA).
Based on the most recent development plans for the site, prepared by GSA, dated October 9, 2020, we
understand that the current project includes demolition and removal of an existing building at the west central
portion of the site, and construction of a new Administration Building with appurtenant structures in the same
general area. The layout of the proposed development is shown on the attached Site Plan, Figure 1. The
administration building will be one- to two-stories, wood-framed, and incorporate post-and-beam floor
construction (crawlspaces). No below-grade levels (basements) are planned. Permanent grade changes at
the site will be minimal.
The building will be supported by conventional shallow, continuous wall (strip) and individual (column pad)
foundations. Per Sheet S0.01 of the plans, the foundations were designed based on an allowable soil
bearing pressure of 2,000 pounds per square foot(psf). In addition, as shown on that plan sheet, the Seismic
Site Class was assigned as Site Class D.
1.2 Scope of Services
Our scope of work included a visit to the site in order to determine if site conditions remained consistent with
those observed during our previous field investigation. Upon confirmation of site conditions, we prepared this
updated geotechnical report to address geotechnical considerations relative to the current (2019) Oregon
Structural Specialty Code (OSSC). No supplemental subsurface explorations were completed for this
assignment.
2.0 SITE SURFACE CONDITIONS
We visited the site on October 15, 2020, in order to confirm existing site conditions. The Crescent Grove
Cemetery consisted of one tax lot totaling approximately 21 acres, and was bordered to the north, south, and
west by Washington Square Mall, and to the east by SW Greenburg Road. The cemetery property generally
sloped to the northwest at gradients less than 10H:1V (Horizontal: Vertical). The majority of the cemetery
property was occupied by burial plots, with the exception of the northern approximately 150 feet of the site,
and the northwestern corner of the property. Several mausoleum structures occupied the western portion of
the property. The area of the proposed Administration Building, hereafter referred to as the "site", was
relatively level to gently descending to the north and occupied by an office building and grass lawns.
The site surface conditions were consistent with those previously observed during our previous investigation
in 2006. Site layout and surface conditions at the time of our recent (October 2020) visit are shown on the
attached Site Photographs, Figure 2.
Carlson Geotechnical Page 4 of 6
Crescent Grove Cemetery Administration Building
Tigard, Oregon
CGT Project Number G2005381
October 27, 2020
3.0 SUBSURFACE CONDITIONS
As part of our 2006 field investigation, we excavated a total of ten test pits within the cemetery property. Two
of the test pits, designated as TP-9 and TP-10, were excavated in relative close proximity to the proposed
Administration Building. The logs of those explorations have been reproduced and are included in the
attached Appendix A. The following summarizes each subsurface material encountered in those test pits.
Silt with Sand Topsoil (OL): Silt with sand topsoil was encountered at the surface of each test pit and
extended to depths of about'/,to 1 foot bgs. This soil was generally hard, gray to light brown and moist.
Undocumented Silt with Sand Fill (ML Fill): Undocumented silt with sand fill was encountered below the
topsoil in each test pit and extended to depths of about 4 to 5 feet bgs. Undocumented fill refers to materials
placed without (available) records of subgrade conditions or evaluation of compaction. This soil was
generally hard, brown to orange-brown, moist, and exhibited some mottling. Various debris, including
concrete and PVC pipes, were encountered at intermittent depths within this soil.
Silty Clay(CL-ML): Silty clay was encountered below the undocumented fill in each test pit and extended to
the full depths explored, up to about 6 feet bgs. This soil was generally stiff to very stiff, blue to grey, moist,
and exhibited low plasticity.
No groundwater or caving was encountered within the depths explored in the two test pits referenced above
and excavated in late August 2006.
4.0 CONCLUSIONS
Based on the results of the 2006 test pit explorations, our recent site observations, and analyses, the site
may be developed as described in Section 1.1 of this report. Satisfactory subgrade support for shallow
foundations and floor slabs associated with the proposed Administration Building can be achieved by the
native, stiff to better, silty clay (CL), or new structural fill that is properly placed and compacted on this
material during construction. This soil was encountered at depths of about 4 to 5 feet bgs within test pits
TP-9 and TP-10 completed in August 2006.
As indicated in our 2006 geotechnical report, it appears the existing silt with sand fill (ML Fill)was placed and
compacted in a controlled manner. Earthwork records (e.g. compaction testing reports, field observation
reports, etc.) could be sought to provide additional information regarding previous grading at the site. In the
absence of such records, due to the presence of various debris (concrete, PVC pipes), we recommend the
undocumented fill materials be completely over-excavated and replaced with structural fill in conformance
with the recommendations presented in the 2006 geotechnical report. If the client and project team desire to
utilize the existing silt with sand fill for support of foundations and/or floor slabs, supplemental investigation
(e.g. test pits, Wildcat dynamic cone penetrometer tests) are recommended to refine its conditions and
suitability to support proposed improvements. Such supplemental investigation could reasonably be
performed by the project geotechnical engineer at the onset of construction, once the earthwork contractor
has mobilized to the site and the existing office building has been removed.
Carlson Geotechnical Page 5 of 6
•
Crescent Grove Cemetery Administration Building
Tigard, Oregon
CGT Project Number G2005381
October 27, 2020
The following section provides updated recommendations for seismic design criteria based on the 2019
Oregon Structural Specialty Code (OSSC). These recommendations supersede those presented in the
"Seismic Design"section of the referenced 2006 report.
5.0 UPDATED RECOMMENDATIONS
5.1 Seismic Site Class
Section 1613.2.2 of the 2019 OSSC requires that the determination of the seismic site class be in
accordance with Chapter 20 of the American Society of Civil Engineers Minimum Design Loads for Buildings
and Other Structures (ASCE 7-16). We have assigned the site as Site Class D ("Stiff Soil") based on review
of geologic mapping, subsurface conditions encountered during our August 2006 investigation, and
experience in the project area.
5.2 Seismic Design
Earthquake ground motion parameters for the site were obtained in accordance with the 2019 OSSC using
the Seismic Hazards by Location calculator on the ATC websitel. The site Latitude 45.449613° North and
Longitude 122.778608°West were input as the site location. The following table shows the recommended
seismic design parameters for the site.
Table 1 Seismic Ground Motion Values
Parameter Value
Mapped Acceleration Parameters Spectral Acceleration,0.2 second (S5) 0.865g
Spectral Acceleration, 1.0 second(Si) 0.397g
Coefficients Site Coefficient,0.2 second (FA) 1.154
(Site Class D) Site Coefficient,1.0 second(Fv)1 1.903
Adjusted MCE Spectral MCE Spectral Acceleration,0.2 second(SMS) 0.998g
Response Parameters MCE Spectral Acceleration,1.0 second(SM1) 0.755g
Design Spectral Acceleration,0.2 second(Sps) 0.666g
Design Spectral Response Accelerations Design Spectral Acceleration,1.0 second(SD1) 0.503g
Seismic Design Category(Risk Category II) D
Value determined from 2019 OSSC Table 1613.2.3(2).
6.0 LIMITATIONS &CLOSURE
This report should be attached to, and considered part of, the referenced September 27, 2006, geotechnical
report. As such, the limitations detailed in the referenced report apply to this updated report. We appreciate
the opportunity to work with you on this project. Please contact us at 503.601.8250 if you have any questions
regarding this report.
Applied Technology Council (ATC), 2020. USGS seismic design parameters determined using "Seismic Hazards by Location,"
accessed October 2020,from the ATC website https://hazards.atcouncil.orq/.
Carlson Geotechnical Page 6 of 6
CRESCENT GROVE CEMETERY ADMINISTRATION BUILDING- TIGARD, OREGON FIGURE 1
Project Number G2005381 Site Plan •
® r' 'ti SITES
y
-aNANO. i(e,) +CONN
SEWER =-24'x5O'TEMPORARY Nor
VAULT TP 9 BUILDING
, LI t` 0, GA`'
L=42.74' 1 . _ tw •Z-. --_ E�ACCESS ROAD GREEN
i1 r =eraemlfenvimi s'r'. ^® .W... r i-.... - "`r -•• ;��. • rar® _
NEW /1
a.� •...,.am- ... . L ..,iJ.aa
+{ r .m. �ra4 �Y.lti.i C.
SWALE I TP 10 I SEE ENLARGED : GAS Ll NE$N WATER L13titE—
1 1 h' R.5.7 STE PLAN `„ l:<# 4b4' 4" r
NEW ELEC.. ', ', ,• �*� # ar t.. FRC NT DOOR TO PROP.LINE aa�,r>
METER 1 A. ri 6� N AC�i 1 ' y S, +..
NEW GAS ai
I0. �. UUILDINV=d' `
METER di I ,� � - F.F.ELEV.:225.X9' — .®(E) L-`
PROTECT --n ,: NA f NEW PRIVATE �i 1144$' -4" . — N ti'fh 1 E5
Ofee7ik(
(E)TREE' ,` eit
�'' f HYDRANT/ FRS ALl SiilLC71 �� ,���^,,�
F
i ) . ,i' -
6 �/ . M "� _
a ' Ex24'TEMP. **.
fX
ti 1 '..fee.elaara OB TRAILER u' 4 t '- ACCESS ROAD#2�
d 8°x2(1'TOOL
V) a 1,SHED (I.! 1,/,_,,s, 0 a 3
-o m ,., ' ,C STRUCTION i
.-., ar ti.P. INGy. •---.
g F9 UTILITY POLE rf (E)E[JR1AL—�—
0 `ems ��` , '. E SEPTIC TAN WE
LOCATIONr PPQ?4ih9t,' '
Oor
.�.,. '' * •. '�k�` °` L
- S p r—z n-xrirsN,r r��c� 1. 0 ..+� �':
LEGEND 1 Inch=100 Feet
Area of proposed new construction
P0
flg'1Nri' Orientation of October 2020 site photographs shown on Figure 2 NOTES:Drawing based on observations made while on site and site
®
503.601.8250plansproduced byGiuletti/Schouten AIAArchitects,dated October 9,
..'
TP-1 N! September 2006 test pit exploration 2020. Test pit locations approximated based on review of 2006
o,a en mnm geotechnical report(see text for further discussion).
FIGURE Z
CRESCENT GROVE CEMETERY ADMINISTRAT/ON BUILDING TIGARD OREGON
Project Number G2005351 Site Photographs
..r W s..t,s. .�y.,, , - , i..;;,,`
-s .wo.;..,..w:y, .: .« .. . -.1
•
Photograph 1 Photograph 2
l ti
.,.: : w,,
q
..n
1
om`
Yt *
IIµpp'
Photograph 3 Photograph 4
PI •y See Figure 1 for approximate photograph locations and directions.
50---- 250 Photographs were taken for confirmation of site conditions.
Drafted by MBM
Carlson Geotechnical Bend Office (541) 330-9155 GP.F`�'SOA_
Eugene Office (541)345-0289 ,,ter I�
A division of Carlson Testing, Inc. Salem Office (503) 589-1252 GEOTECHNICAL
Phone: (503)601-8250 Tigard Office (503)684-3460
www.carlsontesting.com
Appendix A: Reproduced 2006 Test Pit Logs
Crescent Grove Cemetery Administration Building
9925 SW Greenburg Road
Tigard, Oregon
CGT Project Number G2005381
October 27, 2020
Prepared For:
Nancy Felton
Crecent Grove Cemetery
9925 SW Greenburg Road
Tigard, Oregon 97223
Prepared by
Carlson Geotechnical
Logs of 2006 Test Pits TP-9 and TP-10 Attached
Office: 18270 SW Boones Ferry Road, Suite 6, Durham, Oregon 97224
Mailing: P.O. Box 230997, Tigard, Oregon 97281
Carlson Geotechnical FIGURE 13
p+R 0 7185 SW Sandburg Street,Suite 110
_____fit__ Tigard, OR 97223 TEST PIT NUMBER TP-9
Telephone: (503)601-8250
503-601.E2Eo Fax: (503)601-8254 PAGE 1 OF 1
CLIENT Crescent Grove Cemetery PROJECT NAME Crescent Grove Cemetery Expansion
IPROJECT NUMBER G0602906 PROJECT LOCATION 9925 S.W.Greenburg Road, Tigard.OR 97223
DATE STARTED 8/25/06 COMPLETED 8/25/06 GROUND ELEVATION TEST PIT SIZE
EXCAVATION CONTRACTOR Client GROUND WATER LEVELS:
IEXCAVATION METHOD Test Pit AT TIME OF EXCAVATION --
LOGGED BY Gabe Burgess CHECKED BY Ryan Houser AT END OF EXCAVATION —
f NOTES AFTER EXCAVATION --
1 ATTERBERG •
d z til a° LIMITS w
= - rri w CC^ CO
a F DF
F- a p MATERIAL DESCRIPTION w 2 >Caf O D¢ t~u.. z a to w 8 t— )-t_ U <1
I ov � z � ffiai Uv �— oz �� �,c+ n
w 0 CC 20 ,J Q. z z
0,0 a a o
EL LT
":'.,.°. Hard,grey to light brown. SILT With SAND TOPSOIL,
slightly moist
e OL
',•d• p4. Hard, brown to orange-brown,SILT with SAND FILL,moist,
+** some mottled grey/brown GB —
4••i••••• LT 1 +4 12
I ••ya4r•••
o:.••
_ og••••• +4
I+.00•••
04+4.40
�4i'E+•
Large piece of concrete encountered in corner of excavation +4,•.
�•4••••
2.5 Mil +4
Ia* crit GB 2 +4
y•i4a4i4•
♦• ••••.
•
•+4••04•`
a- 4..4.4•••
%•�•••
•
z 5.0 +4•d0.•
2. S` ,000 Stiff to very stiff,blue to grey, SILTY CLAY,low plasticity, ,trt GB 21
Ia NM1400: moist tI g
o Y7 O
:- woo woir ML
y ;rira
y" iv
Slopped excavator at 6 feet
O
m
,u
al
POCarlson Geotechnical FIGURE 14 ,
.. .., lg�t , Ti rg Street,Suite 110
Tigard,OR 97223
113331=3 Telephone. (503)601-8250 TEST PIT NUMBER TP-10
pi 503 b61.9250 Fax: (503)601-8254 PAGE 1 Of
CLIENT Crescent Grove Cemetery PROJECT NAME Crescent Grove Cemetery Expansion
idPROJECT NUMBER G0602906 PROJECT LOCATION 9925 S.W.Greenburg Road,Tigard,OR 97223
DATE STARTED 8/25/06 COMPLETED 8/25f06 GROUND ELEVATION TEST PIT SIZE
EXCAVATION CONTRACTOR Client GROUND WATER LEVELS:
•
MEXCAVATION METHOD Test Pit AT TIME OF EXCAVATION ---
LOGGED BY Gabe Burgess CHECKED BY Ryan Houser AT END OF EXCAVATION -
NOTES AFTER EXCAVATION ---
ATTERBERG 'r-
11111
ii o z w= LIMITS
w
iiia. 0-ci U MATERIAL DESCRIPTION 2 >0 °5 4 w 6 z Q en uWi —I- p i- 5 X a-
w� ° vi aD 0r m0> v to oz d g z
p O <z w �z Cl.0 o 2O -J n.J �z z
0.0
ill IC
.'•.,`• Hard,grey to light brown, SILT with SAND TOPSOIL,
r,.,u, li slightly moist
L:_b.
i,.sti,..i CL
t414iii1 Hard,brown to orange-brown,SILT with SAND FILL, moist,
i`•••••••i some mottled grey/brown —
•••�+�•• White PVC drain pipe cut through at 1.5 feet GB +4
.••••••
+%%
$PM4 $ +4
IIIII •P44,44.
2 5 %i a� ML
�•�i*•�•a• FILL PVC Black flex pipe with 1/2 to 3/4 inch rounded gravel at 2.5
O.000i feet
goo
1 t:s•••i
Kt:t•+
♦•••O.
�iii0ii
♦•• •
1- Wi.*4..
N ii/iiiii Stiff to very stiff, blue to grey, SILTY CLAY, low plasticity, GB
2 5 19 31 24
6�ioio/ moist
oferribfor
a
i/.i/ii
MO
w 5.0 NM
I,'mo,l
ald WOO
o 0.M## ii
` os/o#
i
x mill
z Stopped excavator at 6 feet
J
oIIIIII
s
v
w
II E
u.,U