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GREENLAND

North Hampton

Rye

Existing Subdivision

Site Orientation

Coakley Landfill

Coakley Landfill -- July 20th 2016 Task Force Update

GMZ & Bedrock Groundwater Flow

Direction of groundwater flow

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Monitoring Locations (Groundwater, Surface Water and Sediment)

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Extent of Contamination (1,4-Dioxane)

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MW-4 (ppt) PFOA 756 PFOS 31

MW-8 (ppt) PFOA 262 PFOS 212

MW-5D (ppt) PFOA 61 PFOS 29

MW-9 (ppt) PFOA 656 PFOS 452

BP-4 (ppt) PFOA 58 PFOS 13

MW-11 (ppt) PFOA 693 PFOS 308

MW-5S (ppt) PFOA 647 PFOS 84

Summary of May 2016 PFC Results from OU-1 Wells

Coakley Landfill -- July 20th 2016 Task Force Update 5

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Coakley Landfill -- July 20th 2016 Task Force Update

Coakley Landfill

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July 2016 PFC Residential Well Sampling Locations

PFC Sampling Summary

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• Results for PFCs in residential wells are expected at any moment.

• Results for PFCs at OU-2 monitoring wells are expected during the first week of August.

• The public will be informed of all results as soon as possible.

• The entire data set will be considered to determine next steps.

Coakley Landfill -- July 20th 2016 Task Force Update

Technical Information Contacts

Andrew Hoffman, P.E. Project Manager NH Department of Environmental Services Tel. (603) 271-6778 E-mail: Andrew.Hoffman@des.nh.gov

Gerardo Millán-Ramos Project Manager U.S. EPA - New England, Region 1 Tel. (617) 918-1377 E-mail: Millan-Ramos.Gerardo@epa.gov

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Robin Mongeon, P.E. Supervisor Federal Site NH Department of Environmental Services Tel. (603) 271-7378 E-mail: Robin.Mongeon@des.nh.gov

Coakley Landfill -- July 20th 2016 Task Force Update