Public Involvement Meeting

Draft Phase IV – Remedy Implementation Plan (RIP)

May 17, 2006

Former Raytheon FacilityWayland, Massachusetts

Presented by:Edwin P. Madera and Louis “Chip” Burkhardt

Raytheon Company

Purpose of MeetingDraft Phase IV – Remedy Implementation Plan (RIP)

• For Release Tracking Number (RTN) 3-22408 and Tier IB Permit Number W0405278 (Northern Area of the Site)

• Remedial Clean-up Plan for Northern Area• Update on soil and groundwater data• Proposed remediation activities• Proposed schedule of activities

Update on Other Site Activities • Southern Area Groundwater Remediation Activities

• Wetland Area Monitoring

Question and Answer Period

Locus Map

Area of Proposed Soil Excavation

Draft Phase IV – Remedy Implementation Plan (RIP)

Draft Phase IV – RIP

Purpose of a Phase IV – Remedy Implementation Plan (RIP)– Proposed Remedial Option for Site:

1) Design2) Construction Plans3) Operation, Maintenance and/or Monitoring.

Draft Phase IV – RIPCompounds of Concern

CVOCs – tetrachloroethene (PCE), trichloroethene (TCE), cis-1,2 dichoroethene (cDCE), and vinyl chloride (VC)– Focus of Phase IV remedial activities activities

MTBE– MTBE in groundwater is attributed to a potential release from local

gas station– Raytheon may submit a Down-gradient Property Status submittal

Arsenic– Arsenic in groundwater is naturally occurring– Raytheon may submit a Response Action Outcome (RAO) submittal

Toluene– Identified with Waterloo Profiler during the Northern Area “source

area” investigation– Toluene has not been detected above its RCGW-1 standard in

groundwater samples collected from monitoring wells located in the Northern Area. The detection of toluene above RCGW-1 is not representative of Site groundwater conditions.

Phase IV – RIPCompounds of Concern

CVOCs/Toluene

Ars

enic

MTBE

Compounds of concernencountered:-Chlorinated Volatile Organic

Compounds (CVOCs)

-Toluene

-Arsenic

-Methyl Tertiary Butyl Ether

Source Area Investigation

Northern Area Investigation Area

Source Area – MIP Investigation

0.034

0.073

0.077

0.120

0.175

0.072

0.184 0.231 0.221 0.263

0.457

0.1390.173

0.3930.2360.222

0.1390.1500.3240.166

0.1730.137

0.100

0.079

0.354

0.1920.049

0.036

0.039

0.057

0.053

2.26

2.87

5.10

12.2

0.4110.168

0.359

2.21

0.160

0.1480.064

0.238

51

0.3

0.2

MW-261S

MW-262DMW-262M

MW-262S

MIP-516MIP-517

MIP-518 MIP-519 MIP-520 MIP-521

MIP-522

MIP-523

MIP-524

MIP-525MIP-526

MIP-527

MIP-528

MIP-529

MIP-530

MIP-531MIP-532

MIP-533

MIP-534MIP-535

MIP-536

MIP-537

MIP-538

MIP-539

MIP-540

MIP-541

MIP-542

MIP-543

MIP-501

MIP-502

MIP-503

MIP-504MIP-505 MIP-506

MIP-507

MIP-508

MIP-509

MIP-510 MIP-511

MIP-512

MIP-513 MIP-514MIP-515

Source Area – Chlorinated Volatile Organic Compound Concentrations in Soil

MW-261S

MW-262DMW-262M

MW-262S

MIP-516MIP-517

MIP-518 MIP-519 MIP-520 MIP-521

MIP-522

MIP-523

MIP-524

MIP-525MIP-526

MIP-527

MIP-528

MIP-529

MIP-530

MIP-531MIP-532

MIP-533

MIP-534MIP-535

MIP-536

MIP-537

MIP-538

MIP-539

MIP-540

MIP-541

MIP-542

MIP-543

MIP-501

MIP-502

MIP-503

MIP-504MIP-505 MIP-506

MIP-507

MIP-508

MIP-509

MIP-510 MIP-511

MIP-512

MIP-513 MIP-514MIP-515

MW-551

MW-552

MW-553

B-531A

B-531B

B-534B

B-534A

B-522A

B-531C

B-531D

B-531F

B-530B

B-530C

B-531E

B-525A

B-525B

30,000

3,000

300

Soil Sampling Results

Additional Site Assessment ActivitiesFebruary/March soil sampling– 20 soil samples analyzed for volatile organic compounds (VOCs):

– PCE, TCE, and/or cis-1,2-dichloroethene (cDCE) were detected in 15 samples at concentrations greater than the applicable Method 1 GW-1/S-1 criteria

– 2 soil samples analyzed for polychlorinated biphenyl's (PCBs), Semi-VOCs, extractable petroleum hydrocarbons (EPH), and metals– No PCBs, SVOCs, or EPH were detected– No metals were detected above the S-1/GW-1 criteria

– 1 soil sample analyzed for waste characterization parameters using the toxicity characteristic leaching procedure (TCLP) – No compounds were detected above the regulatory criteria

Source Area Investigation

W E

Area of Proposed Soil Excavation

Total VOC Concentration in SoilEVS Visualization

Ground Surface

West East

Additional Site Assessment Activities (cont.)

Since submittal of the Phase II – Comprehensive Site Assessment– Semi-annual groundwater gauging conducted at all accessible

Site monitoring wells.

– Groundwater samples collected from select monitoring wells at the Site: – 75 groundwater samples analyzed for CVOCs

Groundwater Contour MapUpper Potentiometric Surface

Groundwater Contour MapLower Potentiometric Surface

Source Area TCE Concentration in Groundwater

MW-261S

MW-262DMW-262M

MW-262S

MW-261S

MW-262DMW-262M

MW-262S

MW-551

MW-552

MW-553

MW-551

MW-552

MW-553

100,000

50,000

10,000

5,000

6,200

40

400

3,600

100

NSNS

Groundwater Sampling Data - April 2006

B-229

B-242

B-228

B-241

WP-501

WP-540

WP-515

WP-529

WP-530WP-545

WP-546

WP-548

WP-550

WP-547

WP-549

45,680

34,810

120,000

9,540

1,170

740

17,040

1,800

340

2,370

4,020

2,480

3,850

9,380

9,270 5,970

3,030 B-229

B-242

B-228

B-241

WP-501

WP-540

WP-515

WP-534

WP-520

WP-529

WP-530WP-545

WP-546

WP-548

WP-550

WP-547

WP-549

Waterloo Data - May 2005

Construction Layout – Proposed Work Zone

Proposed Remedial Area

Towards Rt. 20

Soil Remediation

Excavation of Source Area– Installation of one 80’ diameter coffer dam and

potentially a second 60’ diameter coffer dam

– Dewatering and treatment

– Removal of impacted soil to a depth of 25’

– Segregation of “clean” and impacted soils

– Disposal of impacted soils off-site

– Backfill and installation of infiltration gallery

– Restoration of source area to existing conditions

Groundwater Remediation

Monitor groundwater concentrations for one year to allow sub-surface conditions to equilibrate

Implement bioremediation to treat residual plume

Detailed injection plan will be developed based on new groundwater conditions

PIP Schedule

• Draft Phase IV have been submitted for public comment on May 17, 2006– Public comments on Draft Phase IV – RIP due on June 16,

2006 to:Louis BurkhardtRaytheon CompanyMail Stop 1880528 Boston Post RoadSudbury, MA 01776

A summary of the comments received and a response to those comments will be prepared

Documents will be made available at the information repositories (Public Library and Board of Health) and web site

Update on Other Site Activities

• Southern Area Groundwater Remediation Activities• Remedy Operation Status (ROS) report to be

submitted to MA DEP in May 2006• Continue to monitor groundwater to evaluate the

efficacy of the ISCO remedial application

• Wetland Area Monitoring• Currently in third year of annual monitoring, will be

summarized in the ROS report planned for November 2006.

Q & A