B08_Section_J_Attachment_12_Rehab_Exteriors_Ft_Yellowstone_Radon_Assessment_Report.pdf

Tetra Tech

P.O. Box 30615, Billings, MT 59107 618 South 25th Street, Billings, MT 59101

Tel 406.248.9161 Fax 406.248.9282 www.tetratech.com

January 11, 2023

Mr. Tim Mitchell, AIA Hennebery Eddy Architects, Inc.

921 SW Washington Street, Suite 250 Portland, Oregon 97205-2827

Delivered via email tmitchell@henneberyeddy.com

SUBJECT: Radon Assessment Report 16 Historical Housing Units Historic Fort Yellowstone Buildings National Park Service Yellowstone National Park, Mammoth, Wyoming Tetra Tech Project No. 117-8975001.100

Dear Mr. Mitchell:

Tetra Tech, Inc. has completed the radon assessment at the above referenced site. Based on correspondence with you prior to the commencement of the project, Tetra Tech was instructed to conduct a radon assessment for information purposes of the below buildings.

• FMSS 2815 – Double Captain’s Quarters, 1909, Building 2

• FMSS 3851 – Field Officer’s Quarters, 1909, Building 3

• FMSS 5944 & 5847 – Double Officer’s Quarters, 1897, Buildings 4 & 5

• FMSS 5954 & 5956 – Double Officer’s Quarters, 1891, Buildings 6 & 7

• FMSS 5958 – Army Post Headquarters, 1891, Building 8

• FMSS 5961 – Guard House, 1891, Building 9

• FMSS 6022 – Quartermaster Storehouse, 1891, Building 10

• FMSS 6023 – Commissary, 1891, Building 11

• FMSS 6024 – Granary, 1891, Building 12

• FMSS 6031 – Hospital Sergeant’s Quarters, 1894, Building 14

• FMSS 6056 & 6064 – Noncommissioned Sergeant’s Quarters, 1897, Buildings 30 &

• FMSS 6058 & 6062 – Noncommissioned Sergeant’s Quarters, 1891, Buildings 31 &

Details of our assessment are provided below.

RADON ASSESSMENT

Project Background Tetra Tech’s scope of work included radon sampling in various locations at the above referenced buildings. Radon is a naturally occurring, odorless, colorless gas that is generated from the natural radioactive decay of radium and uranium. The uranium concentration of underlying geologic materials is a fundamental variable that determines the rate of underground radon production. Geologic materials that contain greater amounts of uranium, mailto:tmitchell@henneberyeddy.com

Radon Assessment Report 16 Historical Housing Units

Historic Fort Yellowstone Buildings National Park Service

Yellowstone National Park Mammoth, Wyoming such as granites and shales, produce greater amounts of radon. Radon seeps from the soil into buildings primarily through sump holes, dirt floors, floor drains, and cinder block walls, and tracks in foundations and concrete floors.

The U.S. Environmental Protection Agency (EPA) and the U.S. Geological Survey have conducted radon sampling of buildings and homes in Wyoming. Published as the Wyoming- EPA Map of Radon Zones, the survey classified Park County, Wyoming as Radon Zone 1, which indicates a high potential for indoor radon concentrations to exceed the EPA action level. No enforceable regulations exist to control indoor radon levels.

The EPA and Centers for Disease Control (CDC) have used a continuous exposure level of

4.0 Picocurries per liter (pCi/L) as a guidance level at which further testing and/or remedial actions are indicated. The Occupational Safety and Health Administration (OSHA) has established a Maximum Permissible Concentration (MPC) of 100 pCi/L. This is the limit that a worker can be exposed to in 40 hours in a consecutive 7-day period.

Radon Results Mr. Jess McLain of Tetra Tech placed activated charcoal radon test canisters in sixty-four locations on December 13, 2022, and collected the canisters on December 15, 2022. The canisters were submitted along with completed chain-of-custody documentation to Energy Laboratories of Billings, Montana for the analysis of radon in air. Individual results are provided in Table 1 and copies of the laboratory analytical reports are contained in Attachment A. Approximate sample collection locations are presented in Figures 1 through 16.

Table 1 Summary of Radon

Sample ID Sample Location Results (pCi/L)

Building 2 Unit A

3674 Basement Room 2A.001 2.4

3657 First Floor Room 2A.102 1.6

3650 Second Floor Room 2A.203 2.0

3646 Third Floor Room sA.304 2.1

Building 2 Unit B

3653 Basement Room 2B.001 2.6

3651 First Floor Room 2B.102 3.1

3635 Second Floor Room 2B.204 2.0

3548 Third Floor Room 2B.302 2.3

Building 3

3638 Basement Room 3.004 2.4

Historic Fort Yellowstone Buildings National Park Service

Table 1 Summary of Radon

Sample ID Sample Location Results (pCi/L)

3672 First Floor Room 3.102 1.6

3648 Second Floor Room 3.206 1.5

3643 Third Floor Room 3.303 1.7

Building 4 Unit A

3652 First Floor Room 4A.002 3.0

3647 Second Floor Room 4A.205 2.7

3659 Third Floor Room 4A.301 10.5

Building 4 Unit B

3676 First Floor Room 4B.108 6.3

3663 Second Floor Room 4B.201 3.4

3669 Third Floor Room 4B.301 7.2

Building 5 Unit A

3670 First Floor Room 5A.106 4.8

3649 Second Floor Room 5A.202 5.2

3629 Third Floor Room 5A.301 5.0

Building 5 Unit B

3544 First Floor Room 5B.105 3.6

3631 Second Floor Room 5B.205 4.4

3630 Third Floor Room 5B.301 4.7

Building 6 Unit A

3660 Basement Room 6A.001 1.3

3655 First Floor Room 6A.102 8.3

3675 Second Floor Room 6A.202 5.6

3559 Third Floor Room 6A.302 7.1

Building 6 Unit B

3658 First Floor Room 6B.105 3.5

3654 Second Floor Room 6B.207 3.6

Historic Fort Yellowstone Buildings National Park Service

Sample ID Sample Location Results (pCi/L)

3673 Third Floor Room 6B.301 4.0

Building 7 Unit A

3338 First Floor Room 7A.103 1.7

3634 Second Floor Room 7A.203 1.4

3632 Third Floor Room 7A.301 1.2

Building 7 Unit B

3668 First Floor Room 7B.106 1.7

3642 Second Floor Room 7B.205

3514 Third Floor Room 7B.301 1.5

Building 8

3667 First Floor Room 8.101 6.0

Building 9 Unit A

No access

Building 9 Unit B

3640 First Floor Room 9B.101 3.1

3664 Second Floor Room 9B.204 3.3

Building 10 Unit A

3637 First Floor Room 10A.101 1.7

3661 Second Floor Room 10A.201 1.7

Building 10 Unit B

3639 First Floor Room 7B.104 3.1

3656 Second Floor Room 7B.201 2.4

Building 11 Unit A

3554 First Floor Room 11A.108 5.2

3645 Second Floor Room 11A.202 5.3

Building 11 Unit B

3666 Basement Room 11B.001 6.2

Historic Fort Yellowstone Buildings National Park Service

Sample ID Sample Location Results (pCi/L)

3662 First Floor Room 11B.102 3.4

3633 Second Floor Room 11B.204 3.8

Building 12 Unit A

3557 First Floor Room 12A.102 5.2

3665 Second Floor Room 12A.204 6.0

Building 12 Unit B

3644 First Floor Room 12B.102 4.5

3431 First Floor Room 11B.204 4.9

Building 14

3519 Basement Room 14.001 3.9

3568 First Floor Room 14.105 0.5

3616 Second Floor Room 14.202 0.8

Building 30

3535 Basement Room 30.001 7.7

3522 First Floor Room 30.102 2.0

3628 Second Floor Room 30.202 2.4

Building 31

3636 First Floor Room 31.103 0.9

3677 Second Floor Room 31.202 0.9

Building 32

3533 First Floor Room 32.102 0.7

3625 Second Floor Room 32.202 0.8

Building 33

3641 First Floor Room 33.103 1.4 picocuries per liter of air = pCi/L and Bold = Exceeds EPA and CDC continuous exposure levels of 4.0 pCi/L

Historic Fort Yellowstone Buildings National Park Service

CONCLUSIONS AND RECOMMENDATIONS

Laboratory analysis of radon test canisters placed in Buildings 4, 5, 6, 8, 11, 12, and 30 showed that one radon level exceeded EPA and CDC continuous exposure levels of 4.0 pCi/L.

The EPA and CDC recommend that follow-up measurements be conducted if the screening measurement result is between 4 pCi/L to 20 pCi/L. Based on the results, Tetra Tech recommends that additional testing be conducted seasonally for a period of one year.

Based on results of this testing, corrective action may be needed to lower radon levels to below 4pCi/L.

Even if the results of your radon test are below 4.0 pCi/L it is recommended that additional testing be performed in the future to insure that acceptable radon levels have been consistent.

LIMITATIONS

Our opinions are intended exclusively for use by Hennebery Eddy Architects, Inc., and Yellowstone National Park. The scope of services performed by Tetra Tech may not be appropriate to satisfy the needs of other users, and any use or re-use of this document, or the findings presented herein is prohibited and at the sole risk of the user. No additions or deletions are permitted without the express written consent of Tetra Tech. Furthermore, the opinions presented herein are limited by the requested scope of services and the site conditions existing at the time of our investigation. Therefore, our opinions and recommendations may not apply to future site conditions which we have not had the opportunity to evaluate.

It has been a pleasure assisting you with this project. If you have any questions or need additional information, please contact me in our Tetra Tech Billings, Montana office at (406) 248-9161.

Respectfully submitted, Tetra Tech, Inc.

Roger W. Herman, Jr.

Roger W. Herman, Jr.

Asbestos, Lead & IH Services Manager

I:\H-M\Hennebery Eddy Architects\117-8975001 - NPS 17 Housing Units HAZMAT\05-Deliverables\Final\Radon\ Fort Yellowstone- Radon Assessment Report.docx

Figures Attachment A – Laboratory Analytical Report

FIGURES

UNIT B

UNIT A

UNIT B

UNIT A UNIT A

UNIT B

UNIT A

UNIT B

UP

UP

COOL ROOM

2A.002

MECHANICAL

ROOM

W.C.

2A.001

STORAGE

2A.005

2A.003

LAUNDRY

2A.004

UP

HALL STAIRS

HALL STAIRS

UP

MECHANICAL

ROOM

2B.001

W.C.

2B.004

COOL ROOM

2B.005

STORAGE

2B.002 LAUNDRY

2B.003

UP

UP

DN

2A.101

VESTIBULE

2A.101

W.C.

DINING ROOM

2A.102

PARLOR

2A.106

PANTRY

2A.105

2A.103

KITCHEN

2A.104

2A.104

DN

STAIRS

STAIRS

STAIRS CLOSET CLOSET

STAIRS

DN

CLOSET CLOSET

DN

PARLOR

2B.102

DINING ROOM

2B.106

VESTIBULE

2B.101

PANTRY

2B.105

KITCHEN

2B.103

W.C.

2B.104

DN

2.S1.01

2B.101

DN

6" / 1'-0" 6" / 1'-0"

CLOS. CLOS.

BEDROOM

2A.202

CLOSET

BEDROOM

2A.203

BATHROOM

2A.204

CLOS.

BEDROOM

2A.205

2.E2.05

4" / 1'-0"

BEDROOM

2A.201 HALL

STAIRS

CLOSET

CLOSET STAIRS CLOSET

STAIRS

BEDROOM

BATHROOM

2B.203

CLOS. BEDROOM

2B.202

BEDROOM

CLOSET

CLOS. CLOS.

2.E2.02

4" / 1'-0"

HALL

STAIRS CLOSET

6" / 1'-0" 6" / 1'-0"

4" / 1'-0" 4" / 1'-0"

4" / 1'-0" 4" / 1'-0"

2.N3.04 2.N3.03 2.N3.02

BEDROOM

2A.301 2.N3.01

BATHROOM

2A.302

2.W3.01 CLOSET

2.W3.02

BEDROOM

2A.303

CLOSET

HALL STAIRS

HALL STAIRS

2.W3.03

BEDROOM

2A.304

CLOSET

2.W3.04 CLOSET

BATHROOM

2B.303

BEDROOM

2B.301 2.S3.04

2.S3.01 2.S3.02 2.S3.03

3650 3646

BEDROOM

2B.204 www.tetratech.com

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BUILDING #2

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

FIRST FLOOR1

SECOND FLOOR2

THIRD FLOOR3

STAIR HALL

3.001 STAIR HALL DN

CRAWLSPACE

LAUNDRY

3.002

W.C.

3.003

GAME ROOM

3.004

UP

UP

STUDY

3.102 CLOS. UP

LOBBY

3.103

STORAGE

ROOM

3.104

DN

3A.101

VESTIBULE

3.101

HALL

3A.103

PANTRY

3.105

KITCHEN

3.106

PARLOR

3.109

DINING ROOM

3.108

W.C.

3.107

3A.106

3.S1.07 DN

UP

BEDROOM

3.201

3.W2.01 UP

STORAGE

CLOSET

3.202

STAIR HALL

3.W2.02 BATHROOM

3.207

HALL

STORAGE

CLOSET

3.208

CLOSET CLOSET

CLOS.

BATHROOM

3.204

3.W2.03

BEDROOM

3.206

3.W2.04

BEDROOM

3.205

3.S2.03

2 03-A202

CLOS. 3.E2.01

03-A203

2 3.S2.04

4" / 1'-0"

BEDROOM

3.203

4" / 1'-0"

3.N3.02 3.N3.01

CLOS.

BEDROOM

3.302

CLOSET

3.W3.01

3.E3.03

3.W3.02

STAIR HALL

3.W3.03

BEDROOM

3.303 3.E3.02

BATHROOM

3.304

3.E3.01

BEDROOM

3.301

CLOS. BEDROOM

3.305

CLOS.

3.S3.03

3.S3.01 3.S3.02 www.tetratech.com

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BUILDING #3

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

BASEMENT0 FIRST FLOOR1

UNIT A

UNIT B

UNIT A

UNIT B

4.W1.01

LIVING

4A.102

LIVING

4A.102

4.W1.02

DN PANTRY

4A.104

4A.101

VESTIBULE

4A.101

UP

CLOSET

CLOSET

UP

VESTIBULE

4B.101

4B.101

DN

4.W1.05

LIVING

4B.108

4.W1.06

LIVING

4B.108

1/2 BA.

4B.105

PANTRY

4B.106

KITCHEN

4B.102

DN

4B.102A

7 04-A202 4

UP

HALL

CLOSET

4.E1.02

UP

STORAGE

4B.104

HALL LAUNDRY WH/SHWR.

4B.103 4B.102B

4.E1.014.E1.01

KITCHEN

4A.105

4A.105A

DN

4A.105B

04-A202 2

CLOS.

4.W2.01

BEDROOM

4A.202

CLOS.

5" / 1'-0"

4.W2.02

CLOS.

BEDROOM

4A.203

BATHROOM

4A.206

BATHROOM

4A.204 BEDROOM

4A.205 4.E2.03

4.E2.04

HALL

4.W2.03

BEDROOM

4A.201

CLOSET

CLOSET

4.W2.04

BEDROOM

4B.201

HALL DN HALL

DN

DN UP CLOSET

DN HALL

DN

DN UP CLOSET

5" / 1'-0"

CLOS.

BEDROOM

4.W2.05

5" / 1'-0"

BEDROOM

4B.206

4.W2.06

CLOS.

BEDROOM

4B.205

BATHROOM

4B.204

BATHROOM

4B.202 4.E2.01

4.E2.02

5" / 1'-0" 5" / 1'-0"

5" / 1'-0" 5" / 1'-0"

5" / 1'-0" 5" / 1'-0"

4.N3.01

1'-0" / 1'-0"

1'-0" / 1'-0"

ATTIC

4A.301

DN

STAIR HALL

4A.302

4.W3.01

DN

DN

4.W3.02

4.E3.01

4.E3.02

10" / 1'-0"

DN STAIR HALL

4B.302

ATTIC

4B.301

1'-0" / 1'-0"

4.S3.01 1'-0" / 1'-0" 1'-0" / 1'-0"

1'-0" / 1'-0" 1'-0" / 1'-0"

3669 www.tetratech.com

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BUILDING #4

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

FIRST FLOOR1

UNIT A

UNIT B

UNIT A

UNIT B

LIVING

5A.102

DN

DINING

5A.103

PANTRY

5A.104

KITCHEN

5A.105

5A.101

HALL

VESTIBULE

5A.101

UP

CLOSET

CLOSET

UP

VESTIBULE

5B.101

5B.101

PANTRY

5B.103

DN

5.W1.05

LIVING

5B.105

5.W1.06

LIVING

5B.105

UP CLOSET

5.E1.01

STORAGE

HALL CLOSET

KITCHEN

5B.102

HALL

CLOSET

STORAGE

5.E1.02

UP CLOSET

5A.106

W.C.

DN

HALL 5A.107

5B.103

DN

5B.104

W.C.

CLOS.

5.W2.01

BEDROOM

5A.202 5" / 1'-0"

CLOS. BEDROOM

5A.203

5.W2.02

CLOS.

BATHROOM

5A.204 BEDROOM

5A.205

BATHROOM

5A.206 5.E2.04

5.E2.03

HALL DN

5.W2.03

BEDROOM

5A.201

CLOS.

CLOS.

5.W2.04 BEDROOM

5B.201

DN UP ATTIC STAIRS CLOSET

HALL

DN UP ATTIC STAIRS CLOSET

5" / 1'-0"

HALL HALL

DN

5" / 1'-0"

CL

5.W2.05 BATHROOM

5B.204

BEDROOM

5B.206

5.W2.06

CL

CL

BEDROOM

5B.205

BEDROOM

5B.202

BATHROOM

5B.203

5.E2.02

5.E2.01

5" / 1'-0" 5" / 1'-0"

5" / 1'-0" 5" / 1'-0"

5" / 1'-0" 5" / 1'-0"

3.E1.08

1'-0" / 1'-0" 1'-0" / 1'-0"

1'-0" / 1'-0"

ATTIC

5A.301

DN

STAIR HALL

5A.302

5.W3.01 DN

5.W3.02 DN 5.E3.01

5.E3.02

10" / 1'-0"10" / 1'-0"

DN

ATTIC

5B.301

STAIR HALL

5B.302

1'-0" / 1'-0" 1'-0" / 1'-0"

3.E1.06

1'-0" / 1'-0" 1'-0" / 1'-0"

1'-0" / 1'-0" 1'-0" / 1'-0"

1'-0" / 1'-0"

1'-0" / 1'-0"

1'-0" / 1'-0"

1'-0" / 1'-0"

5A.106 www.tetratech.com

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BUILDING #5

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

FIRST FLOOR1

UNIT A

UNIT B

UNIT A

UNIT B

BASEMENT

6A.001

6.W1.01

DINING

6A.102

6.W1.02

LIVING

6A.103

PANTRY

6A.104

W.C.

6.E1.03

6A.106

KITCHEN

6A.105

6A.107

6A.101

HALL

VESTIBULE

6A.101

VESTIBULE

6B.101

HALL

6B.101

KITCHEN

6B.103

6.W1.05

LIVING

6B.106

6.W1.06

DINING

6B.105

PANTRY

6B.104

HALL6B.104

W.C.

6B.102

UP UP

STORAGE

UP UP

REAR PORCH

6A.107

DN

CLOS.

6.W2.01

BEDROOM

6A.202 5" / 1'-0"

6.W2.02

CLOS.

CLOS.

BEDROOM

6A.203

BATHROOM

6A.204

BEDROOM

6A.205

6.E2.03

W.C.

6A.206

6.E2.04

DN

6.W2.03

BEDROOM

6A.201

CL

CL

6.W2.04

BEDROOM

6B.201

DN UP CLOS.

DN

HALL HALL

UP CLOS.

5" / 1'-0"

HALL HALL

DN

6.E2.02

6.W2.05

5" / 1'-0" BEDROOM

6B.206

CLOS.

BEDROOM

6B.205

6.W2.06

CLOS.

BEDROOM

6B.203

BATHROOM

10 W.C.

6B.202 6.E2.01

5" / 1'-0" 5" / 1'-0"

5" / 1'-0" 5" / 1'-0"

5" / 1'-0" 5" / 1'-0"

6.N3.01

1'-0" / 1'-0"

1'-0" / 1'-0"

ATTIC

6A.301

STAIR HALL

6A.302

6.W3.01 6.E3.02

DN

DN

6.W3.02 6.E3.01

10" / 1'-0"

STAIR HALL

6B.302

1'-0" / 1'-0" ATTIC

6B.301

1'-0" / 1'-0"

6.S3.01

1'-0" / 1'-0"

1'-0" / 1'-0"

1'-0" / 1'-0" 1'-0" / 1'-0"

6B.207 www.tetratech.com

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BUILDING #6

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

BASEMENT0

FIRST FLOOR1

UNIT A

UNIT B

UNIT A

UNIT B

BEDROOM

7A.103

LIVING

7A.104

PANTRY

7A.105

7A.106

KITCHEN

7A.106

VESTIBULE

7A.101

VESTIBULE

7B.101

UP

STAIR HALL

7B.102

W.C.

HALL 7B.103

7B.107

KITCHEN

7B.104

BEDROOM

7B.107

PANTRY

7B.105

LIVING

7B.106

CLOS.

7B.101

HALL

7B.102

7 07-A202 4

UP

STORAGE

STAIR HALL

7A.102

UP

HALL

W.C.

7A.107

UP

CLOS. STORAGE

HALL 7A.102

7A.101

DN

DN

CLOS.

7.W2.01

BEDROOM

7A.202 5" / 1'-0"

CLOS.

BEDROOM

7A.203

BATHROOM

7A.204

7.W2.02

CLOS. CLOS. KITCHEN

7A.205 7.E2.03

7.E2.04

7.W2.03

BEDROOM

7A.201

CLOS.

CLOS.

BEDROOM

7B.201 7.W2.04

HALL

HALL

CLOS.

7.W2.05

5" / 1'-0"

BEDROOM

7B.205

7.W2.06

CLOS.

CLOS.

BEDROOM

7B.204

BATHROOM

7B.203

KITCHEN

7B.202

UP

DN CLOSET

DN

DN

CLOS.

UP

DN

5" / 1'-0"

HALL

7.E2.02

7.E2.01

5" / 1'-0" 5" / 1'-0"

5" / 1'-0" 5" / 1'-0"

5" / 1'-0" 5" / 1'-0"

31.E2.25

1'-0" / 1'-0"

1'-0" / 1'-0"

TBD

7A.301

7.W3.01

DN

DN

7.W3.02

BATHROOM

7B.303

7.E3.01

7.E3.02

10" / 1'-0"

1'-0" / 1'-0"

BEDROOM

7B.301

1'-0" / 1'-0"

31.E2.23

1'-0" / 1'-0" 1'-0" / 1'-0"

11" / 1'-0" 11" / 1'-0" www.tetratech.com

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BUILDING #7

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

FIRST FLOOR1

KITCHEN

8.102

8.W1.01 CL

BEDROOM

8.103 BATHROOM

8.104

8.E1.04 VESTIBULE

8.105

1 08-A204 2

8.E1.02

LIVING

8.101

CL

08-A203

8.S1.04

8.N1.04

8A.107 DN

8.S1.05

8.E1.03

8.S1.06

BEDROOM

8.107 BATHROOM

8.106 www.tetratech.com

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BUILDING #8

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

FIRST FLOOR1

UNIT A UNIT B UNIT A UNIT B

DN

DN

KITCHEN

9A.102

BEDROOM

9A.103

BATHROOM

9A.104

BEDROOM

9B.104

KITCHEN

9B.105

CLOSET

HALL

CLOS.

BATHROOM

9B.103

LIVING

9A.101 BEDROOM

9A.105

UP

BEDROOM

9B.102

UP

LIVING

9B.101

BATHROOM

9A.204

CL

BEDROOM

9A.202

DN

BEDROOM

9A.201

6" / 1'-0"

BEDROOM

9A.205

BEDROOM

9B.201

STAIR HALL

9A.203

BATHROOM

9B.202 CL

BEDROOM

9B.203

CLOSET CLOSET

STAIR HALL

9B.205

DN

BEDROOM

9B.204

CL

6" / 1'-0"

5" / 1'-0"

6" / 1'-0"

5" / 1'-0" www.tetratech.com

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BUILDING #9

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

FIRST FLOOR1 SECOND FLOOR2

UNIT A UNIT B

UNIT A

UNIT BUP

CRAWLSPACE

10A.001 BASEMENT

10B.001

CRAWLSPACE

10B.002

DN DN

REAR PORCH

10B.107

BATHROOM

10B.105

KITCHEN

10B.106 10B.108

DINING

DN HALL

TBD

CLOSET

10A.101

LIVING

10B.102

BEDROOM

10B.104

BEDROOM

10B.103

UP

10.W1.01

10A.101A

DN

VESTIBULE

10B.101

DN

10B.103

10.W1.08

10.E2.04 10.E2.03 10.E2.02 10.E2.01

STORAGE

BATHROOM

10B.202

TBD

10A.201

STAIR HALL

10B.205

DN

CLOSET CLOSET

BEDROOM

10B.203

BEDROOM

10B.201

BEDROOM

10B.204

CLOSET CLOSET

10.W2.01 10.W2.02 10.W2.03 10.W2.04

5 1/2" / 1'-0"

5 1/2" / 1'-0"

1'-0" / 1'-0" 1'-0" / 1'-0"

5 1/2" / 1'-0"

5 1/2" / 1'-0" www.tetratech.com

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BUILDING #10

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

BASEMENT0

UNIT AUNIT B

UNIT AUNIT B

UNIT AUNIT B

STORAGE

11B.001

UP

BASEMENT

11A.001

BASEMENT

11B.002

11B.105

REAR PORCH

11B.105

REAR PORCH

11A.107

DN

DINING

11B.103

KITCHEN

11B.104

BATHROOM

11B.106

BATHROOM

11A.105

KITCHEN

11A.106

DINING

11A.108

HALL CLOSET

UP

CLOSET HALL

UP

LIVING

11B.102

LIVING

BEDROOM

11B.108

BEDROOM

11B.107

BEDROOM

11A.104

11A.102

BEDROOM

11A.103

VESTIBULE

11B.101

DN

VESTIBULE

11A.101

DN

11.W2.04 11.W2.03 11.W2.02 11.W2.01

CLOSET STORAGE

BEDROOM

11B.204

BATHROOM

11B.201

STAIR HALL

2B.205

DN

BEDROOM

11B.203

CLOSET CLOSET

BEDROOM

11B.202

BEDROOM

11A.203

STAIR HALL

11A.205

DN

BEDROOM

11A.202

CLOSET CLOSET

BATHROOM

11A.204

CLOSET

BEDROOM

11A.201

STORAGE

11.E2.01 11.E2.02 11.E2.03 11.E2.04

5 1/4" / 1'-0"

5 1/2" / 1'-0"

1'-0" / 1'-0" 1'-0" / 1'-0"

5 1/2" / 1'-0"

5 1/4" / 1'-0" www.tetratech.com

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BUILDING #11

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

BASEMENT0

DN DN

REAR PORCH

12A.106

REAR PORCH

12B.107

DINING

12A.103

BREAKFAST

NOOK

12A.104

KITCHEN

12A.105

BATHROOM

12A.107

BREAKFAST

NOOK

BATHROOM

12B.105

KITCHEN

12B.106 12B.108

DINING

12B.109

HALL HALL

CLOSET

UP

LIVING

12A.102

BEDROOM

12A.109

BEDROOM

12A.108

BEDROOM

12B.104

BEDROOM

12B.103

LIVING

12B.102

STAIRS STAIRS UP

CLOSET

VESTIBULE

12A.101

VESTIBULE

12B.101

STORAGE

CLOSET

BEDROOM

12A.202

STAIR HALL

12A.205

CLOS.

DN

BEDROOM

12A.201

CLOSET CLOSET

CLOSET

BEDROOM

12A.204

CLOS.

STAIR HALL

12B.201

DN

BEDROOM

12B.205

BATHROOM

12A.203

BATHROOM

12B.202

STORAGE

12B.203 CLOSET BEDROOM

12B.204

5 1/2" / 1'-0"

5" / 1'-0"

1'-0" / 1'-0"

1'-0" / 1'-0"

5" / 1'-0"

5 1/2" / 1'-0" www.tetratech.com

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BUILDING #12

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

BASEMENT0

UP

1/2 BATH

14.102

ENTRY

14.101

KITCHEN

14.103

BASEMENT

STAIRSDN

14.104

LIVING

14.106 DINING

14.105

DN

2 14_LEVEL 1 (DEMO)

1/4" = 1'-0"

BASEMENT

14.001

UP

14-A201

14.N2.02

11" / 1'-0"

DN

BATHROOM

14.201 14.W2.01

HALL

CLOSET

11" / 1'-0"

11" / 1'-0" 4" / 1'-0"

14.N2.01

6" / 1'-0" 1" / 1'-0"

14.W2.02

BEDROOM

14.203

CLOS.

BEDROOM

14.202 14.E2.01 www.tetratech.com

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BUILDING #14

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

BASEMENT0

CRAWLSPACE

BASEMENT

30.001 CRAWLSPACE

UP

30.S0.01

CELLAR

30.002

30.W1.01

30.E1.04

BATHROOM

30.108

30.W1.02

BEDROOM

30.107

30.E1.03

PANTRY

30.N1.01

30.E1.02

30.N1.02

30.W1.03

REAR ENTRY

30.104

DN 30A.104

DN

KITCHEN

30.105

UP

VESTIBULE

30.106

ENTRY

30.101

DN

30A.101

BASEMENT

STAIRS

DINING

30.103

LIVING

30.102 30.E1.01

30.S1.01

30.S1.02 30.S1.03

DN

CLOSET

BATHROOM

30.203

7 1/2" / 1'-0" 30.E2.02

7 1/2" / 1'-0"

30.E2.01

BEDROOM

30.202

CLOSET

7" / 1'-0"

CLOSET

STAIR HALL

30.201 www.tetratech.com

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BUILDING #30

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

BASEMENT0

SECOND FLOOR3

CLOSET

BATHROOM

31.203

DN

STAIR HALL

7 1/2" / 1'-0"

CLOS. CLOS.

BEDROOM

31.201 7 1/2" / 1'-0"

CLOSET

BEDROOM

31.202 7" / 1'-0"

CLOSET

KITCHEN

31.105

VESTIBULE

31.106

ENTRY

31.101

UP

DN

UTILITY

31.104

DINING

31.103

LIVING

31.102 www.tetratech.com

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BUILDING #31

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

BEDROOM

32.204

7 1/2" / 1'-0"

BATHROOM

32.203

5 5/8" / 1'-0" CLOSET

BEDROOM

32.202

STAIR HALL

32.201

CLOSET

UP

KITCHEN

32.106

REAR ENTRY

32.105

LIVING

32.102

UTILITY

32.104

DINING

32.103

LAUNDRY

32.107

ENTRY

32.101

DN

3533 www.tetratech.com

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BUILDING #32

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

CLOSET

BATHROOM

33.205

7 1/2" / 1'-0"

BEDROOM

33.202

CLOSET

7" / 1'-0"

BEDROOM

33.204

BEDROOM

33.203

CLOSET

7 1/2" / 1'-0"

STAIR HALL

33.201

CLOSET

KITCHEN

33.105

VESTIBULE

33.106

ENTRY

33.101

UP

UTILITY

33.104

DINING

33.103

LIVING

33.102 www.tetratech.com

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BUILDING #33

RADON ASSESSMENT

RADON SAMPLE LOCATIONS

HISTORICAL FORT YELLOWSTONE BUILDINGS

NATIONAL PARK SERVICE

MAMMOTH, YELLOWSTONE NATIONAL PARK, WYOMING

7100 Commercial Ave, Suite 4 Billings, Montana 59101

PHONE: 406-248-9161 FAX: 406-248-9282

ATTACHMENT A

Laboratory Analytical Report

ANALYTICAL SUMMARY REPORT

Lab ID Client Sample ID Col lect Date Receive Date Matrix Test

B22121288-001 Can ID 3651 12/15/22 8:35 12/15/22 Air Radon in Air

B22121288-002 Can ID 3522 12/15/22 11:31 12/15/22 Air Same As Above

B22121288-003 Can ID 3633 12/15/22 10:35 12/15/22 Air Same As Above

B22121288-004 Can ID 3677 12/15/22 11:45 12/15/22 Air Same As Above

B22121288-005 Can ID 3647 12/15/22 9:06 12/15/22 Air Same As Above

B22121288-006 Can ID 3557 12/15/22 10:20 12/15/22 Air Same As Above

B22121288-007 Can ID 3636 12/15/22 11:40 12/15/22 Air Same As Above

B22121288-008 Can ID 3616 12/15/22 10:47 12/15/22 Air Same As Above

B22121288-009 Can ID 3548 12/15/22 8:25 12/15/22 Air Same As Above

B22121288-010 Can ID 3664 12/15/22 10:06 12/15/22 Air Same As Above

B22121288-011 Can ID 3652 12/15/22 9:04 12/15/22 Air Same As Above

B22121288-012 Can ID 3645 12/15/22 10:35 12/15/22 Air Same As Above

B22121288-013 Can ID 3629 12/15/22 9:22 12/15/22 Air Same As Above

B22121288-014 Can ID 3643 12/15/22 8:55 12/15/22 Air Same As Above

B22121288-015 Can ID 3639 12/15/22 10:15 12/15/22 Air Same As Above

B22121288-016 Can ID 3630 12/15/22 9:30 12/15/22 Air Same As Above

B22121288-017 Can ID 3650 12/15/22 8:36 12/15/22 Air Same As Above

B22121288-018 Can ID 3656 12/15/22 10:04 12/15/22 Air Same As Above

B22121288-019 Can ID 3535 12/15/22 11:30 12/15/22 Air Same As Above

B22121288-020 Can ID 3670 12/15/22 9:20 12/15/22 Air Same As Above

B22121288-021 Can ID 3634 12/15/22 9:35 12/15/22 Air Same As Above

B22121288-022 Can ID 3628 12/15/22 11:35 12/15/22 Air Same As Above

B22121288-023 Can ID 3632 12/15/22 9:40 12/15/22 Air Same As Above

B22121288-024 Can ID 3667 12/15/22 9:55 12/15/22 Air Same As Above

B22121288-025 Can ID 3519 12/15/22 11:00 12/15/22 Air Same As Above

B22121288-026 Can ID 3625 12/15/22 11:50 12/15/22 Air Same As Above

B22121288-027 Can ID 3568 12/15/22 11:04 12/15/22 Air Same As Above

Tetra Tech Billings

Project Name: Mammoth Hot Springs

Work Order: B22121288

7100 Commercial Ave Ste 4 Billings, MT 59101-6270

December 30, 2022

Energy Laboratories Inc Billings MT received the following 64 samples for Tetra Tech Billings on 12/15/2022 for analysis.

B22121288-028 Can ID 3533 12/15/22 11:55 12/15/22 Air Same As Above

B22121288-029 Can ID 3646 12/15/22 8:40 12/15/22 Air Same As Above

B22121288-030 Can ID 3653 12/15/22 8:37 12/15/22 Air Same As Above

B22121288-031 Can ID 3631 12/15/22 9:30 12/15/22 Air Same As Above

B22121288-032 Can ID 3662 12/15/22 10:45 12/15/22 Air Same As Above

B22121288-033 Can ID 3642 12/15/22 9:45 12/15/22 Air Same As Above

B22121288-034 Can ID 3554 12/15/22 10:30 12/15/22 Air Same As Above

B22121288-035 Can ID 3657 12/15/22 8:20 12/15/22 Air Same As Above

B22121288-036 Can ID 3655 12/15/22 9:34 12/15/22 Air Same As Above

B22121288-037 Can ID 3559 12/15/22 9:36 12/15/22 Air Same As Above

B22121288-038 Can ID 3661 12/15/22 10:10 12/15/22 Air Same As Above

B22121288-039 Can ID 3648 12/15/22 8:53 12/15/22 Air Same As Above

B22121288-040 Can ID 3641 12/15/22 12:00 12/15/22 Air Same As Above

B22121288-041 Can ID 3635 12/15/22 8:23 12/15/22 Air Same As Above

B22121288-042 Can ID 3659 12/15/22 9:10 12/15/22 Air Same As Above

B22121288-043 Can ID 3544 12/15/22 9:12 12/15/22 Air Same As Above

B22121288-044 Can ID 3649 12/15/22 9:21 12/15/22 Air Same As Above

B22121288-045 Can ID 3672 12/15/22 8:50 12/15/22 Air Same As Above

B22121288-046 Can ID 3638 12/15/22 8:46 12/15/22 Air Same As Above

B22121288-047 Can ID 3669 12/15/22 9:20 12/15/22 Air Same As Above

B22121288-048 Can ID 3338 12/15/22 9:45 12/15/22 Air Same As Above

B22121288-049 Can ID 3663 12/15/22 9:20 12/15/22 Air Same As Above

B22121288-050 Can ID 3514 12/15/22 9:50 12/15/22 Air Same As Above

B22121288-051 Can ID 3660 12/15/22 9:33 12/15/22 Air Same As Above

B22121288-052 Can ID 3637 12/15/22 10:10 12/15/22 Air Same As Above

B22121288-053 Can ID 3640 12/15/22 10:05 12/15/22 Air Same As Above

B22121288-054 Can ID 3674 12/15/22 8:16 12/15/22 Air Same As Above

B22121288-055 Can ID 3668 12/15/22 9:50 12/15/22 Air Same As Above

B22121288-056 Can ID 3666 12/15/22 10:40 12/15/22 Air Same As Above

B22121288-057 Can ID 3676 12/15/22 9:15 12/15/22 Air Same As Above

B22121288-058 Can ID 3654 12/15/22 9:36 12/15/22 Air Same As Above

B22121288-059 Can ID 3673 12/15/22 9:30 12/15/22 Air Same As Above

B22121288-060 Can ID 3675 12/15/22 9:34 12/15/22 Air Same As Above

B22121288-061 Can ID 3665 12/15/22 10:50 12/15/22 Air Same As Above

B22121288-062 Can ID 3658 12/15/22 9:40 12/15/22 Air Same As Above

B22121288-063 Can ID 3644 12/15/22 10:45 12/15/22 Air Same As Above

The analyses presented in this report were performed by Energy Laboratories, Inc., 1120 S 27th St., Billings, MT 59101, unless otherwise noted. Any exceptions or problems with the analyses are noted in the report package. Any issues encountered during sample receipt are documented in the Work Order Receipt Checklist.

The results as reported relate only to the item(s) submitted for testing. This report shall be used or copied only in its entirety. Energy Laboratories, Inc. is not responsible for the consequences arising from the use of a partial report.

If you have any questions regarding these test results, please contact your Project Manager.

Report Approved By:

B22121288-064 Can ID 3431 12/15/22 10:48 12/15/22 Air Same As Above

Project: Mammoth Hot Springs CLIENT: Tetra Tech Billings

Work Order: B22121288 CASE NARRATIVE 12/30/22Report Date:

GUIDE TO RADON

Radon levels can vary from season to season as well as from room to room. The screening measurement serves to indicate the potential for a radon problem. Depending upon the result of your screening measurement, you may need to have follow-up measurements made to give you a better idea of the average radon level in your home. The EPA has set the action level for Radon at 4 pCi/L.

The following guidelines may be useful to you in determining the urgency of your need for follow-up measurements and remedial actions:

If your screening measurement result is less than 4 pCi/L:

Follow-up measurements are probably not required. If the screening measurement was made with the house closed up prior to and during the testing period, there is relatively little chance that the radon concentration in your home will be greater than 4 pCi/L as an annual average.

If your screening measurement result is 4 pCi/L or higher, perform a follow-up test to be sure.

If your first screening measurement is more than twice EPA’s 4 pCi/L action level, you should take a second short-term test immediately or consult with a certified radon mitigation professional.

If you followed up with a second short term-term test:

The higher your short-term result, the more certain you can be that you should mitigate your home. Consider mitigating your home if the average of your first and second test is 4 pCi/L or higher.

Remember: There is increasing urgency for taking action at higher concentrations of radon. The higher the radon level in your home, the faster you should take action to reduce your exposure.

For more information about Radon in Montana, contact the State Radon Contact MT DEQ, PO Box 200901, Helena, MT 59620. (406) 444-6592, or visit the EPA website: www.epa.gov/iaq/radon

REFERENCES

EPA Document EPA402/K-12/002|2016|www.epa.gov/radon, A Citizens Guide to Radon, May 2012

LABORATORY ANALYTICAL REPORT

Client: Tetra Tech Billings Project: Mammoth Hot Springs Lab ID: B22121288-001 Client Sample ID: Can ID 3651

Collection Date: 12/15/22 08:35

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 11:04 / jdw0.5pCi/L3.1Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL)

Project: Mammoth Hot Springs Lab ID: B22121288-002 Client Sample ID: Can ID 3522

Collection Date: 12/15/22 11:31

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 11:39 / jdw0.5pCi/L2.0Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-003 Client Sample ID: Can ID 3633

Collection Date: 12/15/22 10:35

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 11:51 / jdw0.5pCi/L3.8Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-004 Client Sample ID: Can ID 3677

Collection Date: 12/15/22 11:45

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 12:10 / jdw0.5pCi/L0.9Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-005 Client Sample ID: Can ID 3647

Collection Date: 12/15/22 09:06

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 12:22 / jdw0.5pCi/L2.7Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-006 Client Sample ID: Can ID 3557

Collection Date: 12/15/22 10:20

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

* 12/16/22 12:33 / jdw0.5pCi/L5.2Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL)

* - The result exceeds the Maximum Contaminant Level

(MCL)

Project: Mammoth Hot Springs Lab ID: B22121288-007 Client Sample ID: Can ID 3636

Collection Date: 12/15/22 11:40

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 12:53 / jdw0.5pCi/L0.9Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-008 Client Sample ID: Can ID 3616

Collection Date: 12/15/22 10:47

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 13:08 / jdw0.5pCi/L0.8Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-009 Client Sample ID: Can ID 3548

Collection Date: 12/15/22 08:25

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 13:21 / jdw0.5pCi/L2.3Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-010 Client Sample ID: Can ID 3664

Collection Date: 12/15/22 10:06

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 14:00 / jdw0.5pCi/L3.3Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-011 Client Sample ID: Can ID 3652

Collection Date: 12/15/22 09:04

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 14:16 / jdw0.5pCi/L3.0Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-012 Client Sample ID: Can ID 3645

Collection Date: 12/15/22 10:35

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

* 12/16/22 14:28 / jdw0.5pCi/L5.3Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL)

* - The result exceeds the Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-013 Client Sample ID: Can ID 3629

Collection Date: 12/15/22 09:22

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

* 12/16/22 14:40 / jdw0.5pCi/L5.0Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL)

* - The result exceeds the Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-014 Client Sample ID: Can ID 3643

Collection Date: 12/15/22 08:55

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 14:51 / jdw0.5pCi/L1.7Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-015 Client Sample ID: Can ID 3639

Collection Date: 12/15/22 10:15

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 15:03 / jdw0.5pCi/L3.1Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-016 Client Sample ID: Can ID 3630

Collection Date: 12/15/22 09:30

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

* 12/16/22 15:14 / jdw0.5pCi/L4.7Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL)

* - The result exceeds the Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-017 Client Sample ID: Can ID 3650

Collection Date: 12/15/22 08:36

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 15:27 / jdw0.5pCi/L2.0Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-018 Client Sample ID: Can ID 3656

Collection Date: 12/15/22 10:04

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/16/22 15:38 / jdw0.5pCi/L2.4Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-019 Client Sample ID: Can ID 3535

Collection Date: 12/15/22 11:30

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

* 12/16/22 16:01 / jdw0.5pCi/L7.7Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL)

* - The result exceeds the Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-020 Client Sample ID: Can ID 3670

Collection Date: 12/15/22 09:20

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

* 12/19/22 09:25 / jdw0.5pCi/L4.8Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL)

* - The result exceeds the Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-021 Client Sample ID: Can ID 3634

Collection Date: 12/15/22 09:35

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/19/22 09:49 / jdw0.5pCi/L1.4Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-022 Client Sample ID: Can ID 3628

Collection Date: 12/15/22 11:35

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/19/22 10:06 / jdw0.5pCi/L2.4Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-023 Client Sample ID: Can ID 3632

Collection Date: 12/15/22 09:40

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/19/22 10:20 / jdw0.5pCi/L1.2Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-024 Client Sample ID: Can ID 3667

Collection Date: 12/15/22 09:55

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

* 12/19/22 10:31 / jdw0.5pCi/L6.0Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level QCL - Quality Control Limit ND - Not detected at the Reporting Limit (RL)

* - The result exceeds the Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-025 Client Sample ID: Can ID 3519

Collection Date: 12/15/22 11:00

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/19/22 10:42 / jdw0.5pCi/L3.9Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-026 Client Sample ID: Can ID 3625

Collection Date: 12/15/22 11:50

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/19/22 10:53 / jdw0.5pCi/L0.8Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-027 Client Sample ID: Can ID 3568

Collection Date: 12/15/22 11:04

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/19/22 11:05 / jdw0.5pCi/L0.5Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-028 Client Sample ID: Can ID 3533

Collection Date: 12/15/22 11:55

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/19/22 11:18 / jdw0.5pCi/L0.7Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-029 Client Sample ID: Can ID 3646

Collection Date: 12/15/22 08:40

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/19/22 11:29 / jdw0.5pCi/L2.1Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-030 Client Sample ID: Can ID 3653

Collection Date: 12/15/22 08:37

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR RADON MONITORING

12/19/22 11:40 / jdw0.5pCi/L2.6Radon in Air E520/5-87-004

- The EPA has established an action level of 4 pCi/L at which further testing and/or remedial action are warranted.

Report Definitions:

RL - Analyte Reporting Limit MCL - Maximum Contaminant Level

Project: Mammoth Hot Springs Lab ID: B22121288-031 Client Sample ID: Can ID 3631

Collection Date: 12/15/22 09:30

Matrix: Air

Report Date: 12/30/22

DateReceived: 12/15/22

Prepared by Billings, MT Branch

Analyses Result Units Analysis Date / ByRL Method

MCL/

QCLQualifiers

INDOOR…