Haines Borough Manager David Sosa released the results of a draft helicopter noise study late last week, but he said he doesn’t want to share his impressions of the $41,300 study until others have had time to interpret it for themselves.

“I would rather not have my views influence anyone else’s thoughts on the noise study, so I am remaining mum on this topic so others can form their own opinions,” Sosa said.

Sosa also declined comment on how the borough will use the noise study.

The borough assembly voted in April to solicit bids for a helicopter noise study after it voted in March 2014 to overturn a planning commission decision and approve a conditional use permit for a sister company of heli-ski operator Southeast Alaska Backcountry Adventures to build a heliport at .6 Mile Chilkat Lake Road.

The borough is accepting comments on the draft study through 5 p.m. Friday, June 26. Submit comments to clerk Julie Cozzi at the administration office or email [email protected].

The study measured nine helicopter “noise events” between March 9-15, measuring the sound at four monitoring sites: the actual helipad, a residence nearby the helipad, the road and a neighboring estate.

According to the study, noise measurement results showed the average noise level at each site was fairly consistent, ranging from 30-51 DNL. (The helipad itself was at 69 DNL).

DNL, or Day Night Noise Level, is an average of the overall noise experienced during an entire day. Because the borough doesn’t have any noise standards, the study offered Federal Aviation Administration standards for comparison: Residential uses and schools are compatible with noise up to 65 DNL, and commercial development is compatible with noise up to 75 DNL.

Chilkat Lake Road residents Jessica Plachta and Nicholas Szatkowski, who appealed the assembly’s decision to issue the conditional use permit in Juneau Superior Court, contest many of the study’s findings and methodologies.

Using DNL as a metric doesn’t make sense, because it averages the noise level over a day-long period, making the sound effects seem artificially low, Szatkowski said.

“The noise report is attempting to assert that if you take a very quiet place and add a very loud noise for a relatively short period of time, you get a moderately quiet place, when actually, what you get is a very quiet place with a very loud thing in it,” Szatkowski said.

“If someone bonks you on the head really hard in the morning, and then refrains from bonking your head for the rest of the day, did they actually just touch you gently the whole time? Obviously not,” Szatkowski said.

The study also shows a chart of “Lmax” noise levels at the four sites. These are the highest noise levels reached during a noise event. “This is the metric to which people generally respond when an aircraft flyover occurs,” the study said.

At the helipad, the Lmax was 104.3 decibels. At the nearby home, it was 93.7; at the road, 77.4; and at the nearby estate, 90.

Plachta and Szatkowski also took issue with the helicopter flight paths during the study, which they said didn’t meet the borough’s standards. According to a flight operations agreement with the borough, helicopters should “attain as quickly as practicable after takeoff and maintain a minimum elevation of 1,500 feet above ground level while in flight.”

Plachta said GPS data showed SEABA was flying at less than 200 feet above ground level during most of the 16-mile round-trip between the helipad and a drop-off point.

“The effect of that is two-fold,” Plachta said. “One, it is cheating the sound receptors of an accurate read of the sonic impact of the helicopter. Two, it is blasting anything unfortunate enough to be right below them, birds and bats and anything else. That’s why those flight rules exist, because this valley has wildlife and residences and other values to protect besides helicopter tourism.”

Plachta and Szatkowski submitted complaints to the borough about the low flying.

“Their failure to abide by this requirement was reported to the borough multiple times, and the administration labeled the reports as ‘unsubstantiated allegations’ even though the GPS data showed the citizen reports to be accurate,” Szatkowski said.

“Flying in this manner very significantly changed that sound signature of the helicopters during the noise test period, so that only the Corona property (adjacent to SEABA) experienced sound levels that would occur if the helicopters flew in accordance with the requirements of the tour permit.”

SEABA co-owner Scott Sundberg did not respond to multiple calls asking for his comments on the noise study results.

Several people contacted by the CVN, including planning commissioner Rob Goldberg and Lynn Canal Conservation president Eric Holle, said they hadn’t read the study yet or didn’t have comments on it.

Assembly member George Campbell said he looked over the study’s summary and conclusion sections, but hasn’t yet combed over its finer points.

“It appears to me that the helicopter noise is no greater or no more impact than anything else that is going on,” Campbell said. “Overall it appears to me it’s a nonissue.”

The study was conducted by the Oklahoma-based company Mead and Hunt and California-based BridgeNet International.

View the study at http://www.hainesalaska.gov/administration/draft-haines-noise-report-study-june-2015.