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Environmental Investigation and Cleanup - Hercules Inc./Dyno-Nobel Site

Project Name: Hercules Inc./Dyno-Nobel Site

NYSDEC Project ID: 356001

Summer 2019

Map Showing Hercules Site Overview copyright National Geographic Society, 2010

National Geographic Society, Copyright 2010

The New York State Department of Environmental Conservation (DEC) is committed to a careful and thorough clean-up of the Hercules Inc./Dyno-Nobel Site located at 161 Ulster Ave., Ulster Park, Ulster County.

DEC has postponed selection of the final remedy based on significant public interest expressed at the March 11, 2019, public meeting on the proposed clean-up plan. This allows DEC additional opportunities to share site information, answer questions and gather information from the public, as well as provide an overview of DEC's cleanup process.

Public Involvement Activities

DEC, the Department of Health (DOH) and representatives from Hercules/Dyno-Nobel Companies held two Public Availability Sessions on June 27, 2019. The sessions focused on the history of the site, findings from environmental investigations, and what interim clean-up activities have been performed.

Future public involvement opportunities and project milestones will be announced in community updates.

Sign up with DEC Delivers, DEC's listserv service to receive these updates by email.

Steps of the Process

Based in part on the information received at the June 27 sessions, further study may be warranted. Results of this work will be used to inform the proposed remedy for the site. Ultimately, a Proposed Remedial Action Plan (PRAP) will be released for public comment, and another public meeting will be held as part of the formal process of remedy selection.

Following the PRAP release and public comment period, the selected cleanup plan will be described in a document called a "Record of Decision" that explains why the actions being taken were selected and include a formal written response to public comments received. A detailed design of the selected cleanup will be prepared, and once approved, the cleanup will be performed.

Site Background

Hercules site from an ariel shot looking down -- photo from NYSGIS
Photo By: NYSGIS

Site Description: The Hercules site is located at 161 Ulster Avenue, Ulster Park Ulster County, approximately one mile south of the Village of Port Ewen. The site is an approximately 280-acre parcel, however manufacturing primarily took place within the approximately 100-acre fenced main plant area. Disposal or discharge of wastes took place within the main plant area and within approximately 50 acres on the east side of the rail line in and around a wetland. Dyno Nobel and related companies own additional parcels around the listed site at which some operations or disposal may have taken place and are included in the area targeted for investigation and cleanup.

Manufacturing of explosives, detonators, blasting caps and related materials took place in the developed (main plant) portion of the site. Disposal activities occurred in the plant area and wetland areas in the eastern portion of the property. Most of the surrounding areas are naturally vegetated with cover types ranging from old fields to forested areas.

The site is listed as a "Class 2" site in the State Registry of Inactive Hazardous Waste Disposal Sites (list of State Superfund sites). A Class 2 site represents a significant threat to public health or the environment and action is required.

Summary of the Investigation

The primary contaminants of concern at the site are inorganic (metals) in the soil site-wide and creek sediments and "energetic" (potentially explosive) materials in wetland sediment and in specific locations in the manufacturing area. Volatile organic compounds (e.g., chlorinated solvents such as trichloroethene or TCE) are also present in the groundwater near the former shell plant. The presence of potentially explosive materials complicate implementation of a remedy at this site.

Document Access Information

Fact Sheets and Newsletters Prepared by DEC:

Site-Related Documents

The following are site-related documents (PDFs):

Site-related documents are available for public review at the following locations:

Where to Find Information

Town of Esopus Library
128 Canal Street
Port Ewen, NY 12466
(845) 338-5580

NYSDEC Region 3 Office
21 S. Putt Corners Road
New Paltz, NY 12561
(845) 256-3000

Comments and Questions are always welcome:


Kiera Thompson, PG
Project Manager, NYSDEC
Remedial Bureau C, Section B
625 Broadway
Albany, New York 12233-7014
(518) 402-9662


Kristin Kulow
NYSDOH Oneonta Office
28 Hill Street #201
Oneonta, New York 13820
(607) 432-3911