Environmental Health & Engineering, Inc. 117 Fourth Avenue

Needham, MA 02494-2725

TEL 800-825-5343

781-247-4300 FAX 781-247-4305

P:\17228\Correspondence\Initial EPA Letter_Clarke\Clarke Middle School.docx Page 1 of 7

August 30, 2010 Ms. Kimberly Tisa PCB Coordinator U. S. Environmental Protection Agency Five Post Office Square, Suite 100 Boston, MA 02109-3912 RE: Clarke Middle School, Lexington, Massachusetts (EH&E 17378)

Dear Ms. Tisa:

This letter is intended to provide the U.S. Environmental Protection Agency (EPA) with

information regarding polychlorinated biphenyl (PCB)-contaminated materials that exceed the

allowable levels under the federal PCB regulations. Said materials were identified at Jonas

Clarke Middle School located at 17 Stedman Road in Lexington, Massachusetts (the School).

Environmental Health & Engineering, Inc. (EH&E) is working in conjunction with the Town of

Lexington Director of the Board of Health and the Director of Public Facilities. As part of this

active investigation, exterior caulking materials have been characterized and air samples have

been collected in multiple classrooms in the School.

NATURE OF PCB-CONTAMINATED MATERIAL

EH&E performed a thorough investigation to identify suspect PCB-containing caulking and

sealants used throughout portions of the School. EH&E collected samples in a manner to

investigate the installation and application of caulking materials, including an evaluation of any

evidence indicating window caulking replacement or repair work. Appendix A provides the

locations where the samples were collected. Five unique types of caulking were identified and

sampled. One of the five types of caulking contained PCB concentrations between 790 and

1,900 parts per million (ppm). Table 1 provides the bulk caulking sample results; the laboratory

report is located in Appendix B. Photograph 1 depicts this caulking material and the typical

installation detail between the metal window frame and façade. Photograph 2 depicts a typical

section of the school façade.

P:\17228\Correspondence\Initial EPA Letter_Clarke\Clarke Middle School.docx Page 2 of 7

Table 1 Bulk Sample Results for Polychlorinated Biphenyls from Clarke School, 17 Stedman Road,

Lexington, Massachusetts, June 14 and 15, 2010

Sample ID Description Aroclor 12541,2

(ppmw) Notes 112191 Map location 1, light grey caulk 790 2C (750) 112192 Map location 2, orange caulk 30 2C (2.8) 112193 Map location 3, dark grey caulk 2.6 2C (2.6) 112194 Map location 4, white caulk 1.5 2C (1.4) 112195 Map location 5, white caulk 2.8 2C (2.6) 112196 Map location 6, light grey caulk 1,000 2C (970) 112197 Map location 7, orange caulk 11 2C (11) 112198 Map location 8, black caulk 5 2C (4.8) 112199 Map location 9, dark grey caulk 5 2C (4.6) 112200 Map location 10, light grey caulk 1,900 2C (1,800) 112201 Duplicate of sample 112200, light grey caulk 1,400 2C (1,300) 112202 Map location 11, light grey caulk 1,600 2C (1,500) 112203 Map location 12, dark grey caulk 2.6 2C (2.5) 112204 Map location 13, light grey caulk 1,700 2C (1,500) 112205 Map location 14, light grey caulk 1,600 2C (1,400) 112206 Map location 15, white caulk 1.7 2C (1.5)

ppmw parts per million by weight 1 PCB concentration analysis performed by Groundwater Analytical, Inc., using U.S. Environmental Protection

Agency (EPA) method 8082 (GC/ECD). 2 Aroclor 1016, 1221, 1232, 1242, 1248, and 1260 also tested. All results below reporting levels, unless noted. 1C: Confirmation concentration reported from first column quantification. 2C: Confirmation concentration reported from second column quantification.

P:\17228\Correspondence\Initial EPA Letter_Clarke\Clarke Middle School.docx Page 3 of 7

Photograph 1 Typical Caulking Detail

Photograph 2 Typical Façade Section

P:\17228\Correspondence\Initial EPA Letter_Clarke\Clarke Middle School.docx Page 4 of 7

AIR SAMPLING DATA

Table 2 provides a summary of the air sampling data collected at the School. The laboratory

report is provided as Appendix C. Results of the air samples collected in the school indicate that

airborne concentrations do not approach or exceed the screening level indoor air values

provided by the EPA for middle schools (ages 12 to <15 years; 450 nanograms per cubic meter

[ng/m3]). These samples were collected with the windows and doors in the School closed, and

the air handling and exhaust systems running.

Table 2 Air Sample Results for Polychlorinated Biphenyls as Homologs at Clarke Middle School,

17 Stedman Road, Lexington, Massachusetts, July 21, 2010

Sample ID Location Parameter1 Results (ng/m3)

105520 Third floor, room 349 Monochlorobiphenyls <3.91 Dichlorobiphenyls <3.91 Trichlorobiphenyls 4.85 Tetrachlorobiphenyls 79.0 Pentachlorobiphenyls 65.6 Hexachlorobiphenyls 22.4 Heptachlorobiphenyls <3.91 Octachlorobiphenyls <3.91 Nonachlorobiphenyls <3.91 Decachlorobiphenyl <3.91

Total homologs 171 105521 Third floor, room 321 Monochlorobiphenyls <3.88

Dichlorobiphenyls <3.88 Trichlorobiphenyls <3.88 Tetrachlorobiphenyls 37.8 Pentachlorobiphenyls 41.5 Hexachlorobiphenyls 2.4J Heptachlorobiphenyls <3.88 Octachlorobiphenyls <3.88 Nonachlorobiphenyls <3.88 Decachlorobiphenyl <3.88

Total Homologs 81.4 105522 Third floor room 301 Monochlorobiphenyls <3.89

Dichlorobiphenyls <3.89 Trichlorobiphenyls <3.89 Tetrachlorobiphenyls 16.4 Pentachlorobiphenyls 7.30 Hexachlorobiphenyls <3.89 Heptachlorobiphenyls <3.89 Octachlorobiphenyls <3.89 Nonachlorobiphenyls <3.89 Decachlorobiphenyl <3.89

Total Homologs 23.7

P:\17228\Correspondence\Initial EPA Letter_Clarke\Clarke Middle School.docx Page 5 of 7

Table 2 Continued

Sample ID Location Parameter1 Results (ng/m3)

105523 Duplicate of sample 105522 Monochlorobiphenyls <3.89 Dichlorobiphenyls <3.89 Trichlorobiphenyls <3.89 Tetrachlorobiphenyls 16.3 Pentachlorobiphenyls 6.68 Hexachlorobiphenyls <3.89 Heptachlorobiphenyls <3.89 Octachlorobiphenyls <3.89 Nonachlorobiphenyls <3.89 Decachlorobiphenyl <3.89

Total Homologs 23.0 105524 Second floor, room 207 Monochlorobiphenyls <3.89

Dichlorobiphenyls <3.89 Trichlorobiphenyls <3.89 Tetrachlorobiphenyls 7.30 Pentachlorobiphenyls <3.89 Hexachlorobiphenyls 2.1J Heptachlorobiphenyls <3.89 Octachlorobiphenyls <3.89 Nonachlorobiphenyls <3.89 Decachlorobiphenyl <3.89

Total Homologs 9.40 105525 First floor room 107 Monochlorobiphenyls 2.47J

Dichlorobiphenyls <3.87 Trichlorobiphenyls <3.87 Tetrachlorobiphenyls 2.4J Pentachlorobiphenyls <3.87 Hexachlorobiphenyls 2.55J Heptachlorobiphenyls <3.87 Octachlorobiphenyls <3.87 Nonachlorobiphenyls <3.87 Decachlorobiphenyl <3.87

Total Homologs 7.42 105526 Second floor, room 227 Monochlorobiphenyls <3.89

Dichlorobiphenyls <3.89 Trichlorobiphenyls <3.89 Tetrachlorobiphenyls 16.7 Pentachlorobiphenyls 8.31 Hexachlorobiphenyls <3.89 Heptachlorobiphenyls <3.89 Octachlorobiphenyls <3.89 Nonachlorobiphenyls <3.89 Decachlorobiphenyl <3.89

Total Homologs 25.0

P:\17228\Correspondence\Initial EPA Letter_Clarke\Clarke Middle School.docx Page 6 of 7

Table 2 Continued

Sample ID Location Parameter1 Results (ng/m3)

105527 First floor, room 137 Monochlorobiphenyls <3.87 Dichlorobiphenyls <3.87 Trichlorobiphenyls <3.87 Tetrachlorobiphenyls 18.0 Pentachlorobiphenyls <3.87 Hexachlorobiphenyls <3.87 Heptachlorobiphenyls <3.87 Octachlorobiphenyls <3.87 Nonachlorobiphenyls <3.87 Decachlorobiphenyl <3.87

Total Homologs 18.0 105528 Outdoors Monochlorobiphenyls <3.89

Dichlorobiphenyls <3.89 Trichlorobiphenyls <3.89 Tetrachlorobiphenyls <3.89 Pentachlorobiphenyls <3.89 Hexachlorobiphenyls <3.89 Heptachlorobiphenyls <3.89 Octachlorobiphenyls <3.89 Nonachlorobiphenyls <3.89 Decachlorobiphenyl <3.89

Total Homologs <3.89 ng/m3 nanograms per cubic meter < The analyte was analyzed for, but not detected at, the specific level reported. 1 PCB concentration analysis performed by Alpha Analytical, Inc., using U.S. Environmental Protection Agency

(EPA) Method 10A (GC/MS-SIM).

P:\17228\Correspondence\Initial EPA Letter_Clarke\Clarke Middle School.docx Page 7 of 7

ONGOING WORK

Field investigation activities are planned at the School and include the collection and analysis of

soil and porous materials adjacent to the caulking with elevated PCB concentrations. Once

results from this additional testing are received, an application as part of 40 CFR 761 .61(c) will

be submitted to the EPA.

If you have any questions please feel free to contact either of us at 1-800-TALK EHE

(1-800-825-5343).

Sincerely, Matt A. Fragala, M.S., C.I.H. Joseph G. Allen, D.Sc., M.P.H. Senior Scientist/Project Manager Senior Scientist/Project Executive Appendix A Sample Location Figure Appendix B Bulk Sample Laboratory Report Appendix C Air Sample Laboratory Report cc: Patrick Goddard, Director of Public Facilities, Town of Lexington Gerard Cody, Health Director, Town of Lexington

APPENDIX A BULK SAMPLE LOCATION FIGURES

6

For Official Use Only

Side C

Side A

Side D

District: Lexington School Name: Clarke Middle School

Address: 17 Stedman Road Lexington, MA 02421

School Hours:

In-session Contact: Steven Flynn (781) 861-2450

Off-Hours Contact:

Approach Hazards:

Notes:

2nd Floor Legend

Single Door Double Door Window

Stairs Ramp Elevator Fire Extinguisher Gas Shut-Off Electrical Shut-Off Water Shut-Off Chair Lift Sprinkler Shutoff Generator

Camera

Fire Standpipe

2nd Floor Plan

Side B

305

307

303

301

309

311

313

315

317

319

321 323325

312/Staff Rm

372Lounge

356

354

318A 318B 318C

318

348A/V St

E

T 332Comp Rm

346Comp Rm

370/Comp Rm

373

371

369 367

365 364 362

360357

355

353

351

349

347

345

343 G 342

340338337

335333

331

327

Stair 1

Roof

G

B

St

Pre

p R

m

Pre

p R

m

Prep

Library

318H

318D

318E

318F

StM W ElPrep

B

GSt

St

Roof Access

E

M

Roof

12 13

14

1516

1920212223

24

2526

Roof

Folds Folds

R1718

Folds

Folds

Folds

FoldsElS

FoldsFoldsFoldsFolds

St

J

GSt

FS

FS

FS

FS

Stair 5

Stair 4

Stair 2

FX

FX

FX

FX

FX

FX

FX

FX

FX FX

FX

FX

FX

FX

FX

FX

FX

FX

FX

FX

FX

FX

FX

FX

FX

FX

FX

R

El

7

For Official Use Only

District: Lexington School Name: Clarke Middle School

Address: 17 Stedman Road Lexington, MA 02421

School Hours:

In-session Contact: Steven Flynn (781) 861-2450

Off-Hours Contact:

Approach Hazards:

Notes:

Lower Level Legend

Single Door Double Door Window

Stairs Ramp Elevator Fire Extinguisher Gas Shut-Off Electrical Shut-Off Water Shut-Off Chair Lift Sprinkler Shutoff Generator

Camera

Fire Standpipe

Side A

Side B

Side D

Side C

Lower Level Floor Plan

107/Comp

118

119

125

127

137

Music

Off110Off Music

132 StE

Auditorium

116 St

106105

109114

117 St 115

T

123 St

129 St

Gymnasium

Aerobic R

m

Off

141 St

J

El 134B St

134A

Stag

e

Music St

JB

G

Elec Rm

ElevRm

GirlsLockers

BoysLockers

St

JTSt

Off

T

St

St

St

St

St

St

Stair 2

34

56 7

8 9OHD E

Folding Wall St

StShowers

J

T

Stair 5

E

E

Stair 4

Mech RmSt

St Mech Rm J

AED

Stair 3

FS

F S

FS

FS

Stair 1

FS

FX

FX

FX

FX

FX

FX