Attachment_04_Geotech_report_102116_LTR.pdf

21 October 2016

Una Gilmartin Wiss, Janney, Elstner Associates, Inc.

200 Powell Street, Suite 1650 Emeryville, California 94608

Subject: Geotechnical Investigation Old Santa Fe Trail Building 1100 Old Santa Fe Trail Santa Fe, New Mexico Langan Project No.: 731687401

Dear Ms. Gilmartin:

Langan Treadwell Rollo is pleased to present the results from our recent field exploration for the proposed rehabilitation of the Old Santa Fe Trail Building in Santa Fe, New Mexico (Figure 1). The building is owned and managed by the National Park Service (NPS), it was constructed between 1937 and 1939 out of adobe and wooden beams, it is roughly rectangular in shape with two courtyard areas. The majority of the building is one story with the exception of the two-story eastern wing. Today, approximately 70 NPS employees work out of the building.

SCOPE OF SERVICES

Wiss, Janney, Elstner Associates is evaluating the building to determine if seismic strengthening is advisable. Key to this evaluation is the knowing the appropriate seismic site class. The purpose of our investigation was to determine the seismic site class in accordance with the International Building Code (IBC, 2015). To provide site-specific subsurface information and evaluate the strength of the soil beneath the building, we drilled and logged a boring to 100 feet below ground surface (bgs).

FIELD INVESTIGATION

The boring was drilled between 20 September and 22 September and advanced using a CME- 75 truck-mounted drill rig equipped with an HW wireline rotary wash system. Prior to drilling we obtained the required drill permit from the New Mexico Office of the State Engineer (NMOSE), notified Underground Service Alert (USA), and retained a private utility locator to check for underground utilities in the vicinity of the boring.

The boring was drilled by Geomechanics Southwest, Inc. of Albuquerque, New Mexico. Our field geologist logged the boring and collected representative soil samples for visual

Geotechnical Investigation Old Santa Fe Trail Building 1100 Old Santa Fe Trail Santa Fe, New Mexico Langan Project No.: 731687401

21 October 2016 classification. The boring was drilled in the western parking lot (Figure 2). The boring log is presented on Figure A-1 in Appendix A. The soil encountered in the boring was classified in accordance with the Classification Chart presented on Figure A-2.

Soil and rock samples were obtained using two types of driven split-barrel samplers:

• Sprague and Henwood (S&H) split-barrel with a 3.0-inch outside diameter and 2.5-inch inside diameter, lined with steel tubes and an inside diameter of 2.43 inches.

• Standard Penetration Test (SPT) split barrel sampler with a 2.0-inch outside diameter and 1.5-inch inside diameter, without liners.

The SPT and S&H samplers were driven with a 140-pound automatic hammer falling 30 inches.

The samplers were driven up to 18 inches. The hammer blows required to drive the samplers every six inches of penetration were recorded and are presented on the boring log. A “blow count” is defined as the number of hammer blows per six inches of penetration or 50 blows for six inches or less of penetration. For this investigation, the blow counts required to drive the S&H and SPT samplers were converted to approximate SPT N-values using factors of 0.7 and 1.2, respectively, to account for sampler type and hammer energy and are shown on the boring log. The blow counts used for this conversion were: 1) the last two blow counts if the sampler was driven more than 12 inches, 2) the last one blow count if the sampler was driven more than six inches but less than 12 inches, and 3) the only blow count if the sampler was driven six inches or less.

Upon completion of drilling, the boring was tremie pressure grouted with cement grout in accordance with the plugging plan approved by the NMOSE. All drilling cuttings and fluid were contained in 55-gallon stainless steel drums and temporarily stored onsite until disposal.

SUBSURFACE CONDITIONS AND CONCLUSIONS

The material encountered during our field investigation consisted of mixed sands, gravels, and sandy clays of the Ancha Formation. The Ancha consists of Pliocene to Pleistocene1-aged alluvial deposits (Read et al, 2000). In general the material increased in density with depth and contains varying amounts of clay, sand, and gravel. Two boulders (at least 4 feet in diameter) were encountered at depths of 41 and 78 feet bgs. Bedrock was not encountered during our investigation.

The Site Class was determined using the � method as specified in Section 20.3.3 of ASCE 7 (ASCE, 2010). Based on the data collected in the field, the site is classified as a Site Class C corresponding to very dense soil and soft rock.

The Pliocene and Pleistocene Epochs spanned approximately 5.3 to 2.5 and 2.5 to 0.01 million years ago, respectively.

Geotechnical Investigation Old Santa Fe Trail Building 1100 Old Santa Fe Trail Santa Fe, New Mexico Langan Project No.: 731687401

21 October 2016

If you have any questions regarding our findings or conclusions, please contact us.

Sincerely, Langan Treadwell Rollo

Jane Elliott Richard D. Rodgers Staff Geologist Managing Principal

731687401.01_JFE_OSTB

Attachments: Figure 1: Site Location Map Figure 2: Site Plan Figure A-1: Boring Log Figure A-2: Classification Chart

REFERENCES

International Building Code, 2015, IBC, International Code Council, 30 May 2014.

Minimum Design Loads for Buildings and Other Structures (ASCE/SEI 7-10), American Society of Civil Engineers, Chapter 20 Site Classification Procedure for Seismic Design, 2010.

Read A.S., Koning, D.J., Smith, G.A., Ralser, S., Rogers, J., Bauer, P.W., Preliminary Geologic Map of the Santa Fe 7.5-minute Quadrangle, Santa Fe County, New Mexico, New Mexico Bureau of Geology, May 2000.

FIGURES

NOTES:

World street basemap is provided through Langan’s Esri ArcGIS software licensing and ArcGIS online.

Credits: Sources: Esri, DeLorme, NAVTEQ, USGS, Intermap, iPC, NRCAN. .

0 2,0001,000

Feet

OLD SANTA FE TRAIL BUILDNG

Santa Fe, New Mexico

Date 09/30/16

SITE LOCATION MAP

Project No. 731687401 Figure 1

SITE

Approximate location of boring by Langan Treadwell Rollo, September 2016

EXPLANATION

Approximate scale

0 50 Feet

Date Project No. Figure

SITE PLAN

Santa Fe, New Mexico

OLD SANTA FE TRAIL BUILDING

273168740109/30/16

Reference: ImagePatch.com Ó 2016 Microsoft Corporation, Bing.

O

L

D

S

A

N

T

A

F

E

T

R

A

I L

B-1

B-1

APPENDIX A

2 inches asphalt concrete (AC) SILTY SAND with GRAVEL (SM) red-brown, medium dense, moist, fine- to coarse angular to subrounded gravel

SANDY CLAY with GRAVEL (CL) red-brown, stiff, dry, trace fine subangular gravel

SAND with SILT and GRAVEL (SW-SM) light red with gray mottling, dense to very dense, fine-grained, subangular gravel up to 1/4 inch in diameter, trace mica, isolated calcium carbonate staining

SAND with GRAVEL (SW) light brown to light gray, dense, dry, fine to coarse-grained, subangular to angular gravel from 1/4 to 1/2 inch in diameter, common quartz pebbles

SAND with GRAVEL (SW) light brown, dense, dry, fine to coarse-grained, fine subangular gravel, few angular feldspathic gravel, trace silt, trace pyrite increase in fines, increase in coarse sand

SILTY SAND(SM)

light brown, dense, moist, fine to coarse-grained, trace fine subangular gravel, trace mica

GRAB

S&H

SPT

SPT

SPT

SPT

SPT

SM

CL

SW-

SM

SW

SW

SM

C on fin in g P re ss ur e

Lb s/

S q

F t

D ry

D en si ty

Lb s/

C u

F t

N at ur al

M oi st ur e C on te nt

T yp e of

S tr en gt h T es t

F in es

S he ar S tr en gt h

Lb s/

S q

F t

Hammer weight/drop: 140 lbs./30 inches

Sprague & Henwoood (S&H), Standard Penetration Test (SPT)

Date finished: 9/20/16

J. ElliottLogged by:See Site Plan, Figure 2

9/20/16

Rotary Wash

Hammer type: Automatic

Boring location:

Date started:

Drilling method:

Samplers:

D E

P T

H (f ee t)

LI

T

H O

LO

G

Y

S am pl er

T yp e

S am pl e

B lo w s/

S P

T N

-V al ue

1 MATERIAL DESCRIPTION

SAMPLES

LABORATORY TEST DATA

PROJECT:

A-1a

OLD SANTA FE TRAIL BUILDING

Santa Fe, New Mexico

Figure:

731687401 Project No.:

Log of Boring B-1 T

E S

T G

E O

T E

C H

L O

G

1.

G

P J

T R

.G D

T

0/

1/

SILTY SAND (SM) (continued) increase in sand content

SAND with SILT and GRAVEL (SW-SM) red-brown to yellow-brown, dense, moist, fine-grained, fine to coarse subangular to subrounded feldspathic gravel, abundant mica decrease in gravel, rich with mica

40.5 to 44 ft: boulder

SANDY GRAVEL (GP)

red-brown to red-gray, very dense, moist, predominantly composed of quartz, feldspar, mica, angular to subrounded, few schist gravel increase in mica, metamorphic gravel

B O

U L

D E

R

SPT

SPT

SPT

SPT

SPT

SM

SW-

SM

GP

60/ 4"

60/ 3"

50/ 4"

50/ 3"

C on fin in g P re ss ur e

Lb s/

S q

F t

D ry

D en si ty

Lb s/

C u

F t

N at ur al

M oi st ur e C on te nt

T yp e of

S tr en gt h T es t

F in es

S he ar S tr en gt h

Lb s/

S q

F t

D E

P T

H (f ee t)

LI

T

H O

LO

G

Y

S am pl er

T yp e

S am pl e

B lo w s/

S P

T N

-V al ue

MATERIAL DESCRIPTION

SAMPLES LABORATORY TEST DATA

PROJECT:

A-1b

OLD SANTA FE TRAIL BUILDING

Santa Fe, New Mexico

Figure:

731687401 Project No.:

Log of Boring B-1 T

E S

T G

E O

T E

C H

L O

G

1.

G

P J

T R

.G D

T

0/

SANDY GRAVEL (GP) (continued)

SAND with SILT and GRAVEL (SW-SM) red-gray to red-brown, very dense with medium dense pockets, moist, coarse-grained, fine subrounded gravel, trace clay, sand grains composed of quartz, feldspar, mica slight cementation increase in fine gravel and coarse sand, slight cementation

78 to 82 ft: boulder

MICA SCHIST - closely to intensely fractured, hard, moderately strong to strong, little weathered, medium-grained, biotite and muscovite rich, weak to moderate foliation CLAYEY SAND with GRAVEL (SC) red-brown to yellow-brown and yellow mottling, very dense, moist, fine to coarse-grained with subrounded to subangular gravel

B O

U L

D E

R

SPT

SPT

SPT

SPT

GP

SW-

SM

SC

96/3"

60/ 6"

60/ 2"

60/ 5"

50/ 3"

50/ 6"

50/ 2"

50/ 5"

C on fin in g P re ss ur e

Lb s/

S q

F t

D ry

D en si ty

Lb s/

C u

F t

N at ur al

M oi st ur e C on te nt

T yp e of

S tr en gt h T es t

F in es

S he ar S tr en gt h

Lb s/

S q

F t

D E

P T

H (f ee t)

LI

T

H O

LO

G

Y

S am pl er

T yp e

S am pl e

B lo w s/

S P

T N

-V al ue

MATERIAL DESCRIPTION

SAMPLES LABORATORY TEST DATA

PROJECT:

A-1c

OLD SANTA FE TRAIL BUILDING

Santa Fe, New Mexico

Figure:

731687401 Project No.:

Log of Boring B-1 T

E S

T G

E O

T E

C H

L O

G

1.

G

P J

T R

.G D

T

0/

CLAYEY SAND with GRAVEL (GW-SC) (continued) increase in fine gravel, granite gravel

CLAYEY GRAVEL (GC)

very dense, moist, coarse rounded to subangular gravel

SPT

SPT

SC

GC

116/ 8"

60/ 3"

50/ 2"

50/ 3"

C on fin in g P re ss ur e

Lb s/

S q

F t

D ry

D en si ty

Lb s/

C u

F t

N at ur al

M oi st ur e C on te nt

T yp e of

S tr en gt h T es t

F in es

S he ar S tr en gt h

Lb s/

S q

F t

D E

P T

H (f ee t)

LI

T

H O

LO

G

Y

S am pl er

T yp e

S am pl e

B lo w s/

S P

T N

-V al ue

MATERIAL DESCRIPTION

SAMPLES LABORATORY TEST DATA

PROJECT:

A-1d

OLD SANTA FE TRAIL BUILDING

Santa Fe, New Mexico

Figure:

731687401 Project No.:

Log of Boring B-1 T

E S

T G

E O

T E

C H

L O

G

1.

G

P J

T R

.G D

T

0/

1/

Boring terminated at a depth of 100.7 feet below ground surface.

Boring backfilled with cement grout.

Groundwater not encountered during drilling.

1 S&H and SPT blow counts for the last two increments were converted to SPT N-Values using factors of 0.7 and 1.2, respectively to account for sampler type and hammer energy.

2 Elevation Based on -- Datum

Project No. FigureDate 73168740110/10/16 A-2

CLASSIFICATION CHART

Major Divisions Symbols Typical Names

GW

GP

GM

GC

SW

SP

SM

SC

ML

CL

OL

MH

CH

OH

PTHighly Organic Soils

UNIFIED SOIL CLASSIFICATION SYSTEM

Well-graded gravels or gravel-sand mixtures, little or no fines

Poorly-graded gravels or gravel-sand mixtures, little or no fines

Silty gravels, gravel-sand-silt mixtures

Clayey gravels, gravel-sand-clay mixtures

Well-graded sands or gravelly sands, little or no fines

Poorly-graded sands or gravelly sands, little or no fines

Silty sands, sand-silt mixtures

Inorganic silts and clayey silts of low plasticity, sandy silts, gravelly silts

Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, lean clays

Organic silts and organic silt-clays of low plasticity

Inorganic silts of high plasticity

Inorganic clays of high plasticity, fat clays

Organic silts and clays of high plasticity

Peat and other highly organic soils

Clayey sands, sand-clay mixtures

Range of Grain Sizes Grain Size in Millimeters U.S. Standard

Sieve Size Above 12"

12" to 3"

Classification

Boulders

Cobbles

Above 305

305 to 76.2

Silt and Clay Below No. 200 Below 0.075

GRAIN SIZE CHART

SAMPLER TYPE

C oa rs e-

G ra in ed

S oi ls (m or e th an h al f o f s oi l > n o.

si ev e si ze

Fi ne

-G ra in ed

S oi ls (m or e th an h al f o f s oi l no

. 2 s ie ve s iz e)

Gravels (More than half of coarse fraction >

no. 4 sieve size)

Sands (More than half of coarse fraction <

no. 4 sieve size)

Silts and Clays

LL = < 50

Silts and Clays

LL = > 50

Gravel coarse fine

3" to No. 4 3" to 3/4"

3/4" to No. 4

No. 4 to No. 200 No. 4 to No. 10 No. 10 to No. 40 No. 40 to No. 200

76.2 to 4.76

76.2 to 19.1

19.1 to 4.76

4.76 to 0.075

4.76 to 2.00

2.00 to 0.420

0.420 to 0.075

Sand coarse medium fine

C Core barrel

CA California split-barrel sampler with 2.5-inch outside diameter and a 1.93-inch inside diameter

D&M Dames & Moore piston sampler using 2.5-inch outside diameter, thin-walled tube

O Osterberg piston sampler using 3.0-inch outside diameter, thin-walled Shelby tube

PT Pitcher tube sampler using 3.0-inch outside diameter, thin-walled Shelby tube

S&H Sprague & Henwood split-barrel sampler with a 3.0-inch outside diameter and a 2.43-inch inside diameter

SPT Standard Penetration Test (SPT) split-barrel sampler with a 2.0-inch outside diameter and a 1.5-inch inside diameter

ST Shelby Tube (3.0-inch outside diameter, thin-walled tube) advanced with hydraulic pressure

SAMPLE DESIGNATIONS/SYMBOLS

Sample taken with Sprague & Henwood split-barrel sampler with a 3.0-inch outside diameter and a 2.43-inch inside diameter.

Darkened area indicates soil recovered

Classification sample taken with Standard Penetration Test sampler

Undisturbed sample taken with thin-walled tube

Disturbed sample

Sampling attempted with no recovery

Core sample

Analytical laboratory sample

Sample taken with Direct Push or Drive sampler

Unstabilized groundwater level

Stabilized groundwater level

OLD SANTA FE TRAIL BUILDING

Santa Fe, New Mexico