The U.S. Navy gave further insight to its at Aqua NY’s Seamans Neck Road Water Plant during a Town of Hempstead Board of Zoning Appeals (BZA) hearing Wednesday afternoon.
The Navy plans to install a water filtration system in a building on the northeast part of the plant's property, located at 690 Seamans Neck Rd. along the Levittown-Seaford border. The system will attempt to filter out trace amounts of trichloroethene (TCE) that are showing up in tests at the water plant.
The chemicals originated from work done for the Navy at a Northrup Grumman building approximately two miles north of the plant. Among the purposes of the plant included help with manufacturing of aircraft during World War II. It closed in 1996.
The Navy's efforts are in compliance with records of decision from the New York State Department of Environmental Conservation that were handed down in 2001 and 2003. Presenter Richard Bivone noted that the 2003 decision required the Navy to perform the "monitoring and filtering of water supplies where needed."
Lead engineer David Brayack told the board that trace amounts of the chemicals began showing up in the water five years ago. They were first detected at a level of .5 micrograms per liter, but that level has increased to between 1.7 and 2.4 micrograms per liter. The federal limit for TCE in drinking water is 5 micrograms per liter.
"The concentrations have been consistently less than drinking water standards, but as we've been monitoring this, the concentration levels have been slowly increasing over time," Brayack said. "We've now determined that treatments will be required."
Plans for the filtering system include six 22-foot-high vessels and a backup generator that will provide the area with water when power is out for an extended period of time. They will also need to increase the horsepower of pumps in the site's two underground wells from 150 to 200 to accommodate the new vessels.
BZA member Gerald Wright asked the presenters why the board should trust the Navy to correct the issue when they were the ones who created it in the first place. The presenters indicated that they were required to work with the Nassau County Department of Health to insure that standards were met. They indicated that their tests showed that their system would help prevent TCE levels from reaching a critical level.
Navy officials also noted that the alternative to its planned treatement system would be to shut down the wells at the site and connect the area to a different water system.
Local resident Daniel Lopez, whose property on Dianne Street in Levittown neighbors the plant, expressed concerns with the project. He mentioned worries about traffic and safety, especially with the construction taking place near . He also called the current facility an "eyesore," noting that the current water towers on the site were deteriorating, and worried that the new proposed facility wouldn't be properly maintained.
The Navy appeared before the board even though they are exempt from federal, state and local zoning laws. They indicated that they would be willing to take any recommendations that the board had into consideration.
A temporary treatment system is planned for installation on April 1 while plans for the permanent system continue.