S-4/ECPD/ Waikane Valley

The Waikane Valley Impact Area is a 187 acre site that was used by the Marine Corps for training from 1953 to 1976. It is located within the Waikane Valley Training Area in the Waiahole and Waikane Valleys, on Oahu’s windward side (Kaneohe, Hawaii), approximately 10 miles northwest of Kaneohe Bay (see Figure 1). The former Waikane Valley Impact Area is part of the Navy and Marine Corps Munitions Response Program which is designed to assess site conditions and determine if actions are needed to reduce risks from munitions and explosives of concern (MEC) comprised of unexploded ordnance (UXO), discarded military munitions, and/or munitions constituents (chemical components of munitions) that remain from past training activities.

Sediment samples were analyzed for the explosive compound RDX and metals. RDX was not detected in any of the sediment samples. Copper was detected above the screening level in all of the sediment samples, but the concentrations found are typical for the area. Volcanic soil naturally contains higher amounts of copper and the levels found are not thought to be associated with past military operations on WVIA.

Surface soil sampling was conducted to test for munitions constituents including explosive compounds and 9 heavy metals. Composite soil samples were taken from 35 areas of the site. The composite samples were each a mixture of 10 individual soil samples taken from within each sampling area, that ranged from 10 to 50 feet in diameter.

A detailed walk-through inspection for surface evidence of discarded military munitions and unexploded ordnance and munitions constituents was conducted. This involved making multiple sweeps back and forth on foot across the site by technicians trained to visually identify signs of munitions. The technicians also used specialized metal detectors to locate munitions near the surface.