The Navy has released its final environmental impact statement for activities in the Hawaii Range Complex — the ocean area used for naval exercises — including the controversial use of sonar in Hawaiian waters, The Maui News reported.

The public has until June 9 to comment on the Hawaii Range Complex Final Environmental Impact Statement/Overseas Environmental Impact Statement.

The final EIS provides an assessment of potential impacts associated with the Navy's activities in the ocean and in the air above, including use of sonar, aircraft landings, research, development, testing and other training activities.

The complex spans 270,250 square miles around the Hawaiian Islands, with the primary training grounds set up off the Pacific Missile Range Facility on West Kaua'i.

The final EIS also includes public comments and the Navy's responses to questions raised by the public in earlier hearings, and testimony presented on the Navy's earlier draft and supplemental draft EIS.

The Navy points out in its final EIS that one of the issues that has received many comments is the effects of midfrequency active sonar use and testing in Hawai'i waters.

Environmental groups in Hawai'i and California have challenged the Navy exercises that use active sonar designed for submarine hunting, mine hunting and shipping surveillance.

Environmental and marine research groups say the high sound levels in the water are harmful to whales and dolphins, and can be fatal. The arguments against sonar exercises are based largely on incidents in which whale or dolphin strandings have occurred while sonar exercises were taking place.

Groups such as the Ocean Mammal Institute have ongoing lawsuits in federal court regarding sonar use.

In the final document, the Navy maintains that training and testing activities proposed for the complex are not new, having been conducted for around 40 years.

"No known marine mammal strandings directly related to Navy activities have occurred during this time," the EIS said.

The Navy document supports keeping sonar use at current levels in the complex. There would be no increase in potential effects on marine mammals, it says, while the Navy will be increasing the "tempo and frequency of training events." The Navy would also like to enhance and add research, development, testing and evaluation activities above current levels.

A supplemental draft circulated for public review this past spring indicated that improved data collection showed that the Navy's actual sonar use is less than had been estimated in previous planning.

The EIS says technological advances improved the Navy's ability to assess impacts with three major changes:

• Use of a different methodology for analyzing potential effects of midfrequency active sonar on marine mammals

• Revising estimates on hours of sonar use

• Providing a new, preferred alternative for the Navy's active sonar practices.

For more Maui news, visit www.mauinews.com.