Title

Watermill Lane Emerging Contaminant Water Treatment and Watermain Upgrade Projects

Document Number

N2021006

Document Type

CATEX

Project Description

Project comprises three components: ¿ East Shore Road Water Main Improvements ¿ replace approximately 7,000 linear feet of water main with new 12-inch water main on East Shore Road from Foxwood Road to Hicks Lane. Project has been completed in January 2020. ¿ Middle Neck Road Water Main Improvements ¿ replace approximately 6,100 linear feet of water main with new 12-inch diameter water main on Middle Neck Road from Ellard Avenue to Cutter Mill Road. Project is nearing completion in October 2021. The existing water mains to be replaced are 8-inch and 6-inch diameter cast iron pipe that was installed over 100 years ago. The new water mains will be Class 52 ductile iron pipe. New hydrants will be installed to improve fire protection. Water service connections will be replaced with new copper water services with curb stops, thereby eliminating all lead and lead gooseneck services in project area. ¿ Water Mill Emerging Contaminant Water Treatment ¿ install new Advanced Oxidation process (AOP) and granular activated carbon (GAC) treatment at Watermill Lane station to reduce 1.4‐dioxane, perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) concentrations respectively. Project will include installation of ultraviolet (UV) lamps, hydrogen peroxide addition, and GAC filters at this location. Water Mill Treatment station treats water from 3 production wells: 2, 9, and 11a, which account for 56% of peak hourly demand (approximately 4.39 million gallons per day (MGD) of 7.8 MGD systemwide). Wells 2A and 9 are pumped at 1000 gallons per minute (GPM) and 11A at 1050 GPM. WAGNN draws potable water from two distinct aquifers which underlie the Great Neck peninsula, the Magothy and Lloyd aquifers. They operate 11 production wells and 7 well sites with production averaging 4.203 MGD, peaking 7.8 MGD in water supply. The system production capacity is 18.9 MGD. Currently, WAGNN has only identified these three wells to not currently meet NYSDOH¿s adopted limits on dioxane and PFOA/PFOS in drinking water.

EPA Region/Headquarters Office

OW

State or Territory

NY

Point of Contact

Leslie Temple
202-564-4734
temple.leslie@epa.gov

Date of Issuance

2021-09-08 00:00:00.0

Website

https://www.epa.gov/wifia