Wednesday, October 05, 2011

Construction noise inside a nearby apartment building: way off the charts (though not as bad inside a unit); maybe state, FCR officials should check it out

Maybe Arana Hankin, the state official in charge of Atlantic Yards, and Jane Marshall, a Forest City Ratner executive, should take a relatively brief evening walk from their Fort Greene homes to check out the deafening construction noise at the intersection of Fourth Avenue and Pacific Street.

Marshall recently likened the additional stretch of overnight noise to a dentist's appointment that would be over in a month.

But that's not quite right.

It's probably closer to a long-term dentist's visit without any novocaine. After all, one resident of 568 Pacific Street described it as "torture."

At that building on Monday night, inside a hallway, a visitor registered a 94.0 dB reading on a decibel meter, as shown in the photo at right.

That's way, way off the charts.

(Update October 14: This noise was related to work not under the direct control of Forest City Ratner, but is related to Atlantic Yards.)

Measuring impacts

The upper acceptable limit at night, according to the city and state, is 65 dB, which itself is way above the recommended level of 45 dB, as noted below.

But there's no evidence anyone officially involved in Atlantic Yards has tried to monitor this, or to offer promised mitigations (see below). Hence my suggestion above.

As shown in the chart at left, from a New York State Department of Environmental Conservation (DEC) guidance on noise, sound becomes intrusive as it approaches 70dB.

It becomes annoying at 80 dB.

At 90 dB, it becomes very annoying, and can cause hearing damage after continuous exposure.

Inside the apartment, I'm told, one person generated a reading of 74 dB, while the visitor with the decibel meter found a reading of 64.5 dB.

That figure actually is barely within the range of acceptable, since 65dB is considered the upper limit. Even so, the resident has found it very difficult to sleep.

And, to get more reliable readings, several more visits likely would be necessary.

What was predicted

For some people, apparently, a baseline level of comfort at home gets sacrificed for Forest City Ratner's plan.

That's not what the Empire State Development Corporation said in the 2006 SEQRA [State Environmental Review Quality Act] Findings Statement:
The changes in noise levels due to the project are not of a magnitude that will significantly affect public or mental health. Therefore, no significant adverse health impacts due to noise are expected due to construction and operation of the Project.
The official documents in this case, as shown below, seem to fudge this issue.

Another DEC chart, below, shows how even an increase of 5 dB can be intrusive.


From 55 dB to 65dB

From the DEC guidance:
Most humans find a sound level of 60 - 70 dB(A) as beginning to create a condition of significant noise effect (EPA 550/9-79-100, November 1978).  In general, the EPA’s “Protective Noise Levels” guidance found that ambient noise levels # 55 dBA L(dn) was sufficient to protect public health and welfare and, in most cases, did not create an annoyance (EPA 550/9-79-100, November 1978).  In non-industrial settings the SPL should probably not exceed ambient noise by more than 6 dB(A) at the receptor.  An increase of 6 dB(A) may cause complaints.  There may be occasions where an increase in SPLs of greater than 6 dB(A) might be acceptable.  The addition of any noise source, in a nonindustrial setting, should not raise the ambient noise level above a maximum of 65 dB(A).  
The document notes that walls and windows have some effect, as does distance:
In general, building walls and windows that are closed provide a 15 dB reduction in noise levels...Again, each doubling of the distance from the source of a noise decreases the SPL by 6 dB(A) at distances greater than 50 feet.
Are significant impacts only ones that last two years?

The FEIS, Chapter 17, Construction Impacts, which acknowledges 65 dB as an upper bound, leaves the impression that months-long noise cannot be considered a significant impact. That strikes me as missing the point. It states:
Construction Noise Impact Criteria
The CEQR Technical Manual states that significant noise impacts due to construction would occur “only at sensitive receptors that would be subjected to high construction noise levels for an extensive period of time.” In general, this has been interpreted to mean that such impacts would occur only at sensitive receptors where high noise levels would occur for 2 years or longer... See Chapter 15, “Noise” for an explanation of noise measurement and sound levels. The criteria are as follows:
If the existing noise levels are less than 60 dBA and the analysis period is not a nighttime period, the threshold for a significant impact would be an increase of at least 5 dBA. For the 5 dBA threshold to be valid, the resulting proposed action condition noise level with the proposed action would have to be equal to or less than 65 dBA. If the existing noise level is equal to or greater than 62 dBA, or if the analysis period is a nighttime period (defined in the CEQR criteria as being between 10 PM and 7 AM), the incremental significant impact threshold would be 3 dBA. (If the Existing noise level is 61 dBA, the maximum incremental increase would be 4 dBA, since an increase higher than this would result in a noise level higher than the 65 dBA threshold.) 
I couldn't find where that has been interpreted as needing to last two years. However, surely overnight noise is more of a sensitive issue than daytime noise.

Indeed, as noted by Atlantic Yards Watch:
The CEQR Technical Manual (the manual that sets the guidelines environmental analysis is supposed to follow in New York City) states analysis of significant noise impacts should take place if construction equipment would be operating for a period of more than two years within 1500 feet of a sensitive receptor, but that shorter periods should be assessed if the work is intense (CEQR, 22-3). Likewise, the anticipated duration of each stage or activity should be considered (CEQR, 22-4). "Nighttime (between 10 PM and 7 AM) is a particularly critical time period relative to potential nuisance values for noise level increases (CEQR, 19-20)."
The issue of nighttime noise

The city's current CEQR Technical Manual, dated 2010, states:
410.  IMPACT THRESHOLDS AT RECEPTORS
The selection of incremental values and absolute noise levels should be responsive to the nuisance levels of noise and critical time periods when nuisance levels are most acute. During daytime hours (between 7 AM and 10 PM), nuisance levels for noise are generally considered to be more than 45 dB(A) indoors and 70 to 75 dB(A) outdoors. Indoor activities are subject to task interference above this level, and 70 to 75 dB(A) is the level at which speech interference occurs outdoors. Typical construction techniques used in the past (including typical single‐glazed windows) provide a minimum of approximately 20 dB(A) of noise attenuation from outdoor to indoor areas.

In view of these factors and for the purposes of determining a significant impact during daytime hours, it is reasonable to consider 65 dB(A) Leq(1) as an absolute noise level that should not be significantly exceeded. For example, if the No‐Action noise level is 60 dB(A) or less, a 5 dB(A) or greater increase would be considered significant. If the No‐Action noise level is 61 dB(A), the maximum incremental increase would be 4 dB(A), since an increase higher than this would result in a noise level higher than the 65 dB(A) threshold and is considered significant. Similarly, if the No‐Action noise level is 62 dB(A) Leq(1) or more, a 3 dB(A) Leq(1) or greater change is considered significant.

Nighttime (between 10 PM and 7 AM) is a particularly critical time period relative to potential nuisance values for noise level increases. Therefore, irrespective of the total nighttime noise levels, an increase of 3 dB(A) is typically considered a significant impact during nighttime hours.
If an increase of 3 dB is a significant impact, then surely it's being exceeded. The 2001 manual, in effect when the environmental review was conducted, offers similar language.

Only partial mitigation, and that seems to have stopped

The FEIS, Chapter 17, Construction Impacts, announced mitigation plans, including double-glazed windows and air conditioners, which were partially implemented:
Significant noise impacts were predicted to occur at a number of residential locations during
some portion of the construction periods. The survey showed that the majority of buildings near or adjacent to the project site either have double glazed windows or storm windows. In addition, a large number of residences have some form of alternative ventilation, either window, through-the-wall (sleeve), or central air conditioning. At locations where significant adverse noise impacts are predicted to occur, and where the  residences do not contain both double-glazed or storm-windows and alternative ventilation (i.e.,  air conditioning), the project sponsor would make these mitigation measures available, at no cost for purchase and installation to owners of residences. In addition, as noted in the DEIS, potential significant adverse noise impacts from construction were identified at the upper floors of certain residential buildings on the north side of Atlantic Avenue and potentially on streets north of Atlantic Avenue. For the FEIS, the need for and feasibility of mitigation at these locations were further analyzed. Generally, all of the sites identified north of Atlantic Avenue already have double-glazed windows with sleeves for alternate ventilation. However, residents within the identified zone who do not have doubleglazed or storm-windows and alternative ventilation and choose not to accept the mitigation measures made available, would still be predicted to experience significant adverse impacts from construction noise at these locations.
However, as documented by Atlantic Yards Watch, currently affected residents were outside the zone designated for mitigation, moved in after mitigation was offered, or moved into buildings that were not analyzed in 2006 as containing housing because they were later converted.

Mitigation promises; can more be done?

From the FEIS, Chapter 19, Mitigation:
2. Where feasible, the project sponsors would use quiet construction procedures, and equipment (such as generators, hydraulic lift vehicles, trucks, and tractor trailers) quieter than that required by the New York City Noise Control Code;
3. Generally, the project sponsors would schedule and perform the most noisy work during weekday daytime hours (and not during weekday nighttime or weekend hours)
It's just not always feasible. The chapter adds:
PROPOSED CONSTRUCTION MITIGATION MEASURES
Even with the incorporation of the impact minimization measures discussed above, because of  the extent, magnitude, and duration, there would be significant adverse impacts from the proposed project’s construction activities on local traffic and noise. The following mitigation measures would be implemented to further reduce these significant adverse impacts:
....NOISE  
The Pacific Branch of the Brooklyn Public Library would experience a significant adverse noise impact over a three year period. To address this impact, the project sponsors would make available to the library, and install, interior-fitted storm windows on the facades facing Pacific Street. In the event the library elects to not  accept the offer, there would be an unmitigated significant noise impact for this three year period.
There would be significant adverse noise impacts at the Dean Playground from construction activities. The project sponsors have committed  to working with DPR to work with DPR’s planned improvements to the Dean Playground. This commitment would partially mitigate a temporary noise impact on the playground due to construction activities. At the Temple of Restoration, the project sponsors will make available storm windows for windows on the second level of the building (above the Temple of Restoration sign), which face Dean Street, and do not currently either have double-glazed windows or storm windows. With this measure, maximum interior noise levels within the Temple of Restoration building would be in the range of 40-50 dBA l10, which would satisfy  CEQR Technical Manual recommended interior noise level requirements for this church use.
Where project implemented measures are not sufficient to prevent significant adverse noise impacts from occurring, and where the residences do not contain both double-glazed or stormwindows and alternative ventilation (air conditioning), the project sponsors would make these mitigation measures available, by purchasing and installing at no cost to the owners of residences. At non-residential locations, such  as open spaces, receptor controls such as sound barriers may not be feasible because of safety and aesthetic concerns. 
A week ago, I asked Empire State Development if more could be done to assist residents enduring noise. I still haven't gotten a response.

What's an ideal level?

It also addresses project buildings, which haven't yet been built, but whose residents would experience construction:
BUILDING ATTENUATION FOR PROJECT BUILDINGS
The CEQR Technical Manual has set noise attenuation values for buildings based on exterior noise levels. Recommended noise attenuation values for buildings are designed to maintain interior noise levels of 45 dBA or lower, and are determined based on exterior L10(1) noise levels. The Phase I building attenuation includes the effects of both project-generated traffic and construction of the Phase II components. The proposed project buildings would include both double-glazed windows and central air-conditioning (e.g., alternative ventilation). These measures would provide a minimum of 35 dBA attenuation. With these measures, interior levels would be below 45 dBA L10. However, there may be some limited periods of time when construction operations may produce noise levels which exceed 80 dBA. These events would be of limited duration. During these time periods, interior noise levels would temporarily exceed the 45 dBA L10 limit, and be above recommended and desirable interior levels
(Emphases added)

It all depends on what "limited duration" means.

33 hours later: impacts still felt

On Monday night at about 11 pm, I went to the corner of Fourth Avenue and Pacific Street to film a crew tearing up the road.

The noise inside the subway station was already significant, and it was very loud when I went upstairs. I walked past the construction activity at the northeast corner of Pacific and Fourth and across the street.

I never got much closer. I stood more than 70 feet away across Pacific Street, then walked west and across wide Fourth Avenue. I turned around and walked back across Fourth, and placed myself on the south side of Pacific, not directly across from the work.

Then after I turned the camera off, I walked east, away from the construction work, and along Flatbush Avenue, heading for the subway station.

I was in the area for less than seven minutes, and close to the construction work only briefly.

This morning, my ears still ache somewhat.

So residents enduring overnight work might just have a legitimate grievance.

Another view

here's another view of construction, apparently from One Hanson Place north of Atlantic, posted on 9/1/11.

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