HomeMy WebLinkAboutVibration notes rev9 FINAL - jkPage | Vibration - 1 Rev9
VIBRATION IMPACTS TO PROPERY AND QUALITY-OF-LIFE
Potential Project-related impacts from vibration related to excavation, construction and truck traffic cut
across a number of areas of concern. These include impacts to historic properties, and quality of life for
nearby residents. Information on vibration impacts is dispersed across numerous sections of the DEIS
and its appendices, and that information has not been well integrated or consistently interpreted.
Items 5 and 6 under Transportation Impacts in the DEIS scope calls for discussions of “the impacts of
vibration from loaded trucks on structures along the vehicle route(s)”, and the effects of excavation and
vibration from machinery, heavy equipment and trucks on structures surrounding the site." Under
Construction-Related Impacts the scope calls for discussions of the vibration impacts associated with
construction of the temporary haul road (item 11), and the effect of excavation and ground vibration
from the operation of machinery, heavy equipment and trucks on existing neighboring structures (items
12 and 13) (p.21).
The DEIS conclusion that there “are also no vibration impacts expected from soil excavation or
construction activities” (DEIS p. iv) is not supported by data in the DEIS, and is likely incorrect 1.
Vibration impacts are briefly addressed in four sections of the DEIS: 1) a discussion of soils, based on
information from the geotechnical report (DEIS Section 2.1.2, pp.37-38; Appendix H)2, 2) a discussion of
potential transportation impacts (Heavy Vehicle Traffic Induced Vibrations)(DEIS Section 3.3.2, p.213), 3)
a discussion of potential construction-related impacts (DEIS Section 3.10.3, pp.273, 274, and 275); and 4)
a discussion of potential vibration impacts to cultural resources (DEIS Section3.11, pp. 281, 283,387, and
288.
The Planning Board’s review of the adequacy of the original DEIS states, in regard to the DEIS’ discussion
of traffic impacts, that “[T]his discussion on this section of potential large adverse impacts is
INADEQUATE. There is a direct connection to the magnitude and duration of potential large adverse
impacts on the quality of the life of residents and visitors, residences (vibration), community character,
and infrastructure (road damage) along an entire route due to the total number of vehicle trips
proposed” (caps in original; emphasis added). In addition, the Planning Board’s consultant notes, in their
May 6, 2022 memo, that the original “DEIS does not adequately address the quality-of-life impacts
associated with significant noise (as well as dust and potential vibration) associated with the necessary
heavy construction trucks on local roadways. The applicant has provided no meaningful and enforceable
mitigation to address these impacts” (emphasis added) (p.4).
1 The DEIS conclusion, stated in the Executive Summary is contradicted at several places in the DEIS text, where it is noted that
vibration impacts may be a concern (e.g., pp. xxx, xxxi, xxxiv, xxxvii, xxxviii). It also contradicts the conclusion that at least one
historic property (the Water Tower and Accessory Building at 3380 West Mill Road likely will be affected by vibration.
2 The DEIS text is identical to the text in Appendix H, and consists of the entire portion of the PWGC Geotechnical Engineering
Memo Report (GEMR) dealing with vibration.
Page | Vibration - 2 Rev9
The assessment of vibration impacts in the original December 2021 DEIS relied on information contained
in the PWGC Geotechnical Engineering Memo Report (GEMR) prepared by PWGC (DEIS Appendix H).
However, the revised DEIS now contains an additional stand-alone vibration analysis prepared by
SoundSense (DEIS Appendix R) which is summarized in the main body of the DEIS. These two studies
contain contradictory information and conclusions relevant to assessing the noise impacts of the
Project. The GEMR has not been updated to reflect the information in the new Acoustic Report, and the
Acoustic Report never refers back to the GEMR.
The DEIS does not adequately or correctly address how vibration impacts will affect the quality of life
for residents near the Project site or along the Project haul truck routes.
The Geotechnical Engineering Memo Report (GEMR) (DEIS Appendix H)
The Geotechnical Engineering Memo Report (GEMR) prepared by PWGC dated August 3, 2021 (DEIS
Appendix H), devotes its final three text paragraphs to “Vibrations.” This discussion is deficient and
misleading, and contains inaccurate data. It does not constitute an adequate basis for evaluating
Project-specific impacts. It appears to be standard boilerplate language and implies that vibration
impacts associated with on-site construction activities (including use of the on-site haul road) will not
affect “nearby residential properties.” It does not address vibration impacts associated with off-site
traffic along the Project’s truck routes. This is one of the noted inadequacies in the original DEIS.
The GEMR states that the “US Bureau of Mines RI 8507 report is the common reference for establishing
safe construction vibration levels. Acceptable vibration levels for modern wood-framed residential
structures are established to be a maximum of 0.5 in/second.” The complete title of RI 8507 is
“Structure Response and Damage Produced by Ground Vibration from Surface Mine Blasting” (emphasis
added). The use of blasting standards to evaluate construction traffic impacts, or impacts from other
non-blasting construction activities, is inappropriate. As at least one vibration damage assessment
expert has noted that “While there is much to be learned about vibration effects from blasting studies,
blasting vibration standards are acknowledged in those blasting studies as inappropriate for
construction settings where, as with traffic, vibration can be effectively continuous for minutes, hours,
weeks, months or even years in some large projects (emphasis in original) . . . The all-too-common use
of blasting vibration standard limits in construction settings other than blasting is directly scientifically
contradicted and creates a high probability of damage to structures” (Ziegler nd)3.
Traffic on streets and highways can be a semi-continuous source of low-level vibration. Depending on
the distance of the structure from the road and the type, speed and amount of the traffic, vibrations
may be felt, particularly from large, heavy trucks passing at high speed. It has long been recognized that
the semi-continuous nature of traffic vibrations requires lower acceptable peak particle velocities (PPV)
3 https://vibrationdamage.com/cvdg_ex_sum.htm
Page | Vibration - 3 Rev9
than those acceptable in short duration blasting. The same document cited in the GEMR, USBM RI 8507,
clearly states that “The safe level criteria established for blasting are often applied to these situations
with little justification. Traffic is usually a steady-state source of low amplitude. Appropriate safe levels
would have to be lower than for blasting, which is relatively infrequent and of shorter duration" (USBM
1980:72).
The GEMR does not address the effects of vibration associated with construction traffic (primarily large
loaded and unloaded haul trucks) along the Project’s proposed off-site truck routes (West Mill Road and
Cox Neck Road, Sound Avenue, Northville Turnpike, and County Rt. 58). It cites the CALTrans
Transportation and Construction Guidance Manual, noting that it contains a table indicating that
“Loaded Trucks” will generate an expected PPV (Peak Particle Velocity) at 25 feet away of 0.076
in/second.4 The GEMR goes on to state that this PPV value is “lower than the 0.5 in/sec threshold and
will be separated from nearby residential properties at larger distances than 25 feet.” There are several
problems with this statement.
First, according to the FTA’s Transit Noise and Vibration Impact Assessment Manual (2018)5 PPV is often
used in monitoring of construction vibration (such as blasting) since it is related to the stresses that are
experienced by buildings and is not used to evaluate human response” (FTA 2018:110; emphasis added).
In other words, the standard cited in the GEMR is not appropriate for use in evaluating impacts to the
quality of life of “public and user groups” as required by the DEIS scope.
Second, the one-size-fits-all “loaded truck”6 CALTrans PPV standard of 0.076 in/sec should not be
indiscriminately applied. Factors such as truck size, weight, suspension type and characteristics, tire
type and configuration, specific to the types of vehicles actually proposed for use on the Project need to
be identified before actual PPV values can be established.
Another significant factor in deriving the PPV value associated with haul trucks is the condition of the
road surface. As the FTA notes: “Rough track or rough roads are often sources of excessive vibration.
Maintaining a smooth surface will reduce vibration levels” (FTA 2018:114).
“Vehicle contact with irregularities in the road surface (e.g., potholes, cracks and uneven
manhole covers) induces dynamic loads on the pavement . . . These loads generate
stress waves, which propagate in the soil, eventually reaching the foundations of
4 The CalTrans guidance is not cited in the Vibration Report included in the revised DEIS.
5 The FTA’s Transit Noise and Vibration Impact Assessment Manual is cited as the basis for the Project noise evaluations in
Appendix R. It is also cited in the Vibration Report (DEIS Appendix R prepared for the Project by SoundSense. However, it is
NOT cited in the Acoustic Report (also in DEIS Appendix R), also prepared by SoundSense. This is one of the many examples
discipline specialists involved in preparing the DEIS not communicating with one another.
6 The “heavy trucks” used by CALTrans to define the standard included “heavily-loaded water truck, or dump truck (preferably
25 tons or greater GVW)” (CALTrans 2013:22). The Project’s loaded haul trucks will weigh 107,000 pounds.
Page | Vibration - 4 Rev9
adjacent buildings and causing them to vibrate. Traffic vibrations are mainly caused by
heavy vehicles such as buses and trucks.
“When a bus or a truck strikes an irregularity in the road surface, it generates an impact
load and an oscillating load due to the subsequent “axle hop” of the vehicle. The impact
load generates ground vibrations that are predominant at the natural vibration
frequencies of the soil whereas the axle hop generates vibrations at the hop frequency
(a characteristic of the vehicle’s suspension system). If the natural frequencies of the soil
coincide with any of the natural frequencies of the building structure or its components,
resonance occurs and vibrations will be amplified” (Hunaidi 2001).
A study by the Road Research Laboratory notes that road surface irregularities on the order of 20 mm
[0.79 in] in amplitude can cause peak particle velocities in the ground of up to 5 mm/s [0.197 in/sec] at
which level “architectural damage'” may occur in buildings. However, before this level is reached,
vibrations become intrusive and even annoying to occupants of buildings (at about 2.5 mm/s) [0.098
in/s] and complaints may result. Vibrations increase in severity with dynamic axle load. As heavy axle
loads are increasing both in magnitude and number, vibrations are likely to become more widespread
(Whiffin and Leonard 1971).
The condition of the road surface along the Project truck route is of special importance for several
reasons, and has major implications for the Project. Most roads comprising the Project truck route
(West Mill and Cox Neck Roads and Sound Avenue) are non-engineered roads in far from perfect
condition. It is not unreasonable to assume that the thousands of heavy truck trips over these roads,
over an assumed period of seven months (the construction period identified by the Project Applicant),
will result in significant deterioration of these road surfaces.
The DEIS’ acknowledges that “heavy vehicles operating along the highway can induce vibrations, but the
extent that this occurs is dependent on the surface condition of the roadway itself. A heavy vehicle
riding on a smooth surface would generate little vibration, while the same vehicle riding over a rough
surface will generate vibrations, [and that] [T]hose vibrations can be transmitted in the existing ground
material to structures in proximity” (DEIS p.224). Vehicle weight, speed, and roadway conditions, are all
factors in determining the intensity of vehicle -generated vibration.7 However, the DEIS goes on to
dismiss concerns about truck traffic induced vibrations by claiming that a) the “sandy soil that Cox Neck
Road/West Mill Road lies upon is not conducive to the transmission of vibrations created by trucks”
(p.228), and b) the “Applicant would commit to quickly repairing any potholes that appear in the
roadway during the construction activity to minimize the potential for vibrations that could affect
7 K.R. Czech (2016), The Impact of the Type and Technical Condition of Road Surface on the Level of Traffic-Generated
Vibrations Propagated to the Environment, Procedia Engineering 143:1358-67. Advances in Transportation Geotechnics 3. The
3rd International Conference on Transportation Geotechnics. This study found that “cases of deterioration of the technical
condition of bituminous pavement roads . . . are associated virtually in every case by a significant increase in the level of
vibrations propagated to the environment [for trucks over 18 tons]: up to [an]18-fold increase.
Page | Vibration - 5 Rev9
existing structures.” The first claim is problematic; the second is vague as no specific procedure is
identified.
The GEMR is cited as the basis for the conclusion in the DEIS that soils under the truck routes are “not
conducive to the transmission of vibrations created by trucks” (DEIS p. 224). In fact, the geotechnical
report says only that “the [onsite] soils of Stratum 2 8 are favorable for limiting vibration effects”
(emphasis added).9 However, other data in the GEMR suggest that that statement is not completely
accurate. Most of the near surface soils (Stratum 1), as recorded in the boring logs in the GEMR, do
indicate (because of associated blow-count values less than 10), that they are loose or very loose, and
therefore “favorable for limiting vibration.” The GEMR describes them as “loose in terms of relative
density.” However, the same boring logs indicate that Stratum 2 soils (those more than four feet below
surface) are associated with blow-counts between 10 and 30 indicating medium-dense soils, and blow-
counts between 30 and 50 (as high as 49 in boring B-12, located at the site of the proposed retaining
wall), indicating dense soils. THE GEMR concludes that “The medium dense to dense soils of Stratum 2
are favorable for limiting vibration effects.” In fact, these higher density sands are less likely to
attenuate vibration effects than the “loose” soil found in Stratum 1.
Traffic-generated vibration will travel through near-surface soils. However, near-surface Stratum 1 soils
will be removed from the Project site during the early part of the Project’s excavation phase. During
much of the excavation phase, and all of the construction phase, construction equipment, as well as
haul trucks maneuvering within the Project site, will be in direct contact with Stratum 2 soils which have
a higher density, and are therefore more conducive to transmitting vibration than near surface soils.
No information is presented in the DEIS concerning soil types underlying the Project truck routes 10. Even
if low-density sandy soils are present, no mention is made of the fact that the dampening effect of sandy
soils may be less during winter months (the Project excavation phase, when most haul truck activity will
take place) when frozen ground conditions may exist.
The DEIS, based on information in the Traffic Study (Appendix O), notes that in May 2021 the Southold
Highway Superintendent advised that Cox Neck Road/West Mill Road were in “fair condition. There are
some rough locations but for most part fine.” The DEIS goes on to note that a “resurfacing with 1-1/2
inches of Type 6 asphalt of Cox Neck Road from North Road (CR 48) to Bergen Avenue” is planned, but
has been “delayed until it is determined how the SYC Project will be conducted, with preference to
performing the resurfacing after the SYC work is complete” (DEIS p. 202). The DEIS also notes that the
Nassau – Suffolk Transportation Improvement Program has “no projects involving the reconstruction
and improvement of roadways serving SYC [Strongs Yacht Club] prior to its expected completion” (DEIS
8 Stratum 2 refers to soils found from 4 ft to 55 ft below surface (Geotechnical Engineering Memo Report, p.2).
9 A condition also assumed in the Vibration Report.
10 The soil survey map included as Figure 6 in Appendix A of the DEIS delineates soil types only for the Project site proper.
Page | Vibration - 6 Rev9
p.202). As noted above, the condition of a pavement surface is a key variable affecting the severity of
traffic-induce vibration.
“Specific pavement surface irregularities, such as potholes and stepped transverse
cracks, can significantly increase the force of the tire striking the pavement. Compared
to the static force, the dynamic force may be up to 50 to 80 percent higher. The higher
dynamic forces result in proportionately higher groundborne vibration. Consequently,
main generators of highway traffic induced vibration are specific surface irregularities . .
The condition of the pavement surface is the decisive contributor to ground-borne
vibration.” (Hajek et al. 2006:5-7)11.
The GEMR (DEIS Appendix H) recommended orienting the proposed haul road in a manner that could
reduce vibration impacts and this appears to have been done. However, the DEIS does not indicate that
other recommendations to minimize vibration impacts have been adequately considered. The GEMR
recommends “[Reducing} vibrations by locating the haul road at sufficient distances from nearby
residences”. However, the GEMR does not indicate what that distance should be. The GEMR also
recommends “Select[ing] a foundation system for the Boat Storage Buildings that will produce minimal
vibrations to construct. Other than describing the foundations as concrete slabs, the DEIS is silent on this
issue.
The DEIS states, in the context of discussing Phase 3 (Construction) activities, that “No fill material is
proposed” (p.34). It also states that “No fill is proposed as part of the proposed action” (p.80). However,
it is unclear from the context in which these statements are made, whether they apply to the entire
Project or, in the case of the latter phrase, just the relatively small areas where the two I/A OWTS 12
systems will be installed. The GEMR suggests that some filling will be required, and notes that some fill
may need to be “compacted with a smooth-drum vibratory compactor, vibratory plate or Rammax
trench compactor”. Attachment 4 (Minimum Everwall Requirements) to the Evergreen Wall Report
(Appendix H) states that “Backfill [behind the wall] must be compacted to min. 95% relative density . . .
at maximum lifts of 16” . . . Preferably use Rammax self propelled sheep foot vibratory roller, min.
weight 1000 lbs = 450 kg, minimum 6 passes.” The DEIS text does not mention vibration or noise impacts
associated this activity, and the DEIS never mentions the use of soil compacting equipment. Vibratory
rollers are not included on the list of equipment identified in the DEIS (pp. xxx, xxxi, p.18, 19 and
Appendix F) for use during construction of the retaining wall.13
11 Hajek, Jerry J., Chris T. Blaney, and David K. Hein. Mitigation of Highway Traffic-Induced Vibration, paper presented at the
Session on Quiet Pavements: Reducing Noise and Vibration, 2006 Annual Conference of the Transportation Association of
Canada.
12 Innovative and Alternative On-Site Wastewater Treatment System.
13 The Vibration Report (DEIS Appendix R) includes woodchippers and tub grinders pieces of equipment that will be used on the
Project site. The report equates the reference vibration values for these items as being equivalent values in the FTA
Guidelines for vibratory rollers.
Page | Vibration - 7 Rev9
The GEMR, however, recommends that “[C]ompaction activities should be conducted under full-time
inspection.” This recommendation is not addressed in the DEIS.14 As a result, the magnitude of vibration
impacts during the construction period may have been underestimated.
The Applicant has agreed to have haul trucks maintain a maximum speed of 30 mph along Cox Neck
Road/West Mill Road, as opposed to the posted 35 mph limit, as a means of reducing vibration impacts.
In fact, the posted speed limit along West Mill Road and most of Cox Neck Road is 30 mph—not 35 mph.
No mechanism is proposed to insure that posted speed limits will be adhered to. The Applicant has also
proposed quickly repairing any potholes that appear in the roadway during the construction activity to
minimize the potential for vibrations that could affect existing structures (DEIS pp. xxxvi, xxxix, 224-225,
228, 298). The problems, uncertainties, and impracticalities of this have been discussed in comments
concerning Project traffic impacts.
Finally, the DEIS notes that “vibrations of significant levels can be eliminated with avoiding disruptive
practices such as installation of driven piles or sheet pile installation”. However, since the DEIS
acknowledges that these types of processes are not proposed as part of the Project, it is unclear how
not doing something that is not proposed as part of the Project is relevant.
The DEIS’ concludes that “there are no vibration impacts expected from soil excavation or construction
activities” (pp. iv, 38). This is contradicted numerous times in the DEIS when it acknowledges 1) the
need to orient the proposed haul road to mitigate potential vibration impacts; 2) have construction
trucks maintain distance from the historic Old Water Tower on West Mill Road to minimize vibration
impacts; 3) quickly make road repairs to “minimize the potential for vibrations that could affect existing
structures”; and 4) the medium to dense soils on the Project site would limit vibration effects.
“Mitigate” does not mean eliminate or reduce to the point of no concern/no impact. Nor does
“minimize” or “limit.”
The GEMR relies on inappropriate standards, and equally inappropriate generic estimates of vibration
generating sources such as trucks and construction equipment, to reach its conclusions.
Vibration Report (DEIS Appendix R)
The GEMR is dated August 3, 2021. It was the principal source of data used in the evaluation of
potential vibration impacts in the original December 2021 DEIS. In response to concerns raised by the
Southold Planning Board (noted above) and OPRHP/SHPO 15 about potential vibration impacts, a
14 This recommendation is not mentioned in the Acoustic Report included in the revised DEIS (see below). This is another
example of a failure of the various discipline specialists who prepared the DEIS to coordinate with one another.
15 The New York State Office of Parks Recreation and Historic Preservation/State Historic Preservation Officer
Page | Vibration - 8 Rev9
separate Vibration Report has been incorporated into the revised DEIS as part of Appendix R.16 That
report goes into considerably more detail than the GEMR.17
“On August 2nd, 2022, SoundSense documented the existing vibration conditions at
various locations near the Project Site and vibration data from a representative truck
expected to be used during construction. The measurements collected provide a
baseline for existing conditions and have been used in the predictions completed for the
Project. Predicted vibration levels were used in conjunction with the methodology and
data from the Federal Transportation Authority’s 2018 Transit Noise and Vibration
Impact Assessment Manual (“FTA Guidelines”) and the New Hampshire Department of
Transportation’s 2012 Ground Vibrations Emanating from Construction Equipment
(“New Hampshire Guidelines”) . . . The predicted vibration compiled by SoundSense can
be compared to the criteria provided in the FTA Guidelines” (DEIS Appendix R, p.3).
There are questionable aspects about the methodology used to collect and analyze the data included in
DEIS Appendix R (Vibration Report).
The Vibration Report states that it utilized methodology and data from FTA Guidelines and the NHDOT
Guidelines. According to Table 6 in the Vibration Report, using the equations that comprise the FTA and
NHDOT guidelines methodology, the “minimum distance to cause no damage to residential structures is
11 feet.” However, there are problems with how both sets of guidelines were used to assess vibration
impacts to structures that might be affected by the Project.
The vibration analysis uses two equations from the FTA Guidelines to determine the “safe distances at
which construction vibration would no longer be a concern for structural damage or disturbance to
occupants inside a structure both for truck traffic and operating construction equipment” (DEIS
Appendix R, p.11).
The first of these equations (Equation 3 in the Vibration Report) is given as
𝑃𝑃𝑃𝑃𝑃𝑃𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒𝑒=𝑃𝑃𝑃𝑃𝑃𝑃𝑟𝑟𝑒𝑒𝑟𝑟∗(25/𝐷𝐷)1.1
This equation has been modified from the one given in the FTA Guidelines methodology. The final
exponent has been reduced from the 1.5 in the FTA Guidelines to 1.1. The Vibration Report justifies this
with the statement that “Long Island’s unique soil structure typically attenuates vibration more
16 Vibration Existing Conditions and Expected Impacts: Strong’s Yacht Center – 5780 West Mill Road – Mattituck, NY. Prepared
by Sound Sense, November 3, 2022. The report inexplicably starts with a Section 3.6 that does not have any relationship to
sections in the DEIS
17 The revised DEIS states that “Although the geotechnical engineering analysis concluded no expected vibration impacts,
additional vibration analyses were undertaken by SoundSense . . .” (DEIS p. 38). As documented above, the GEMR was
completely inadequate in regard to assessing potential vibration impacts.
Page | Vibration - 9 Rev9
effectively than many other soils of geological areas” (DEIS Appendix R, p.10). This justification is not
supportable. As discussed above, in relation to the GEMR, while near-surface soils at the Project site do
have vibration attenuating characteristics, these soils will be removed during the early part of the
Project’s Excavation Phase. During much of the excavation phase, and all of the construction phase,
construction equipment, as well as haul trucks maneuvering within the Project site, will be in direct
contact with soils which have a higher density, and are therefore more conducive to transmitting
vibration. In addition, even if low-density sandy soils are present, no mention is made of the fact that
the dampening effect of sandy soils may be less during winter months (the Project excavation phase,
when most haul truck activity will take place) when frozen ground conditions may exist. The
modification of the equation has the effect of minimizing the projected severity of potential impacts to
nearby structures from truck-generated vibration.
The second equation (Equation 4 in the Vibration Report) is given as
𝐿𝐿𝑣𝑣.𝑑𝑑𝑒𝑒𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑑𝑒𝑒=𝐿𝐿𝑣𝑣𝑟𝑟𝑒𝑒𝑟𝑟−30 log(𝐷𝐷/25)+1
Both equations require the use of a “source reference vibration level at 25 feet” (PPVref and Lvref). A
source reference vibration level is the established vibration associated with the operation of a particular
piece of construction equipment. Table 5 in the Vibration Report, “Reference Data Utilized for Analysis,”
indicates that a reference PPV of 0.076 was taken from the FTA Guidelines. However, the Vibration
Report analysis indicates that the “loaded trucks” in the FTA Guidelines are equivalent to “water/fuel”
trucks. Those types of trucks generally weigh only a fraction of what the fully loaded Project haul trucks
will weigh. In addition, although the NHDOT Guidelines also note that the FTA Guidelines use a reference
value of 0.076, the NHDOT Guidelines cite other studies that make it clear that this value is not a
generally accepted constant.18,19,20
The FTA Guidelines state that “[S]electing sites for an ambient vibration survey requires good judgment.
Sites selected to characterize a transit corridor should be distributed along the entire project where
potential for impacts have been identified” (emphasis added) (p.151). The vibration analysis for the
Project relies on information collected from only one location (Location 4) along the entire Project truck
route.
18 Final Environmental Impact Statement by the U.S. Department of Transportation, Federal Transit Administration and the Port
Authority of New York and New Jersey, Permanent WTC Path Terminal in Borough of Manhattan, New York County, Chapter
10: Noise and Vibration, May 2005. This document reports loaded trucks have a PPV of 0.85 at 5 feet, 0.30 at 10 feet, 0.11 at
20 feet, and 0.06 at 30 feet.
19 Report on the Pre-Design Studies of Noise and Ground Vibration for N.W.L.R.S., City of Calgary (Oct. 1986), Appendix C,
Vibration Study, Antelope Valley Roadway Project, University of Nebraska, Lincoln, Nebraska. This document reports heavy
trucks have a PPV of 0.25 at 30 meters (99 feet).
20 Readings compiled from Study of Vibrations due to Construction Activities on Haleakala, LeEllen Phelps, Mechanical
Engineering Group, Document TN-0113, Revision A, ATST (Advanced Technology Solar Telescope), Appendix Q: Vibration
Study, July 8, 2009. This document reports large semi-trucks have a Max PPV of 0.010 at 50 feet, 0.0475 at 75 feet, and 0.010
at 150 feet.
Page | Vibration - 10 Rev9
The FTA Guidelines also call for 4 to 10 passbys for each test. The language in the Vibration Report
suggests that only a single pass was made for the test conducted as part of the test described in the
Vibration Report.
Because of the identified problems with the way that potential vibration damage to nearby residences
was assessed, the Planning Board should obtain the services of an outside consultant to re-evaluate
potential vibration impacts.
The preparers of the DEIS and the Vibration Report, although they cite the NHDOT Guidelines, and rely
on it for their assessment of potential vibration damage, failed to make use of the construction vibration
assessment procedure described in detail in those guidelines. “The “Construction Vibration Assessment
Table” (Appendix A, Table 1) in the NHDOT Guidelines (COMMENT FIGURE VIBRATION-1) “can be
routinely used by designers for determining if vibration concerns exist and for evaluating the potential
impact on a Project. The assessment matrix described in Appendix A assigns a point score to ten
different categories of data that could potentially influence the impact of construction vibrations on a
NHDOT project. The total point score from adding the ten categories is used to determine the level of
impact at a site from vibrations emanating from a specific type of construction activity” (p.17).
Applying the NHDOT assessment matrix to assess the severity of vibration impacts to structures along
the Project truck route results in a score of 215 to 313 based on the following assigned values for
structures located within 50 feet of the road.
Type of Construction Activity heavy wheeled construction vehicles 3 pts
Attenuation of PPV non-cohesive soil (loose)21 3 pts
Displacement; Densification loose soil 27 pts
Distance from Vibration Source 50 ft or less 81 pts
Type of vibration 22 single isolated event or continuous 1-81 pts
Duration of Construction Activity longer than 1 week 81 pts
Type of Structure private residence w/drywall or plaster walls 9-27 pts
Condition/Age of Structure structure constructed after or prior to 1950 9-27 pts
Sensitivity of Population single family residence 1 pt
For structures between 51 and 100 feet from the Project truck route, scores range from 161 to 259.
21 Sand is classified as a non-cohesive soil. Loose non-cohesive soils are associated with a value of 11-24 blows/ft. According to
the boring logs in the geotechnical report prepared for the Project (DEIS Appendix H), blow counts associated with the near
surface sands have blow count values less than 10 blows/ft.
22 According to the NHDOT Guidelines rolling energy transfer (heavy vehicles, railroads) are pseudo-steady vibrations, which
can generate a large range of vibration intensities and some subjective judgment is required when rating this category.
Page | Vibration - 11 Rev9
According to the NHDOT Guidelines, a point score of 300 to ˂400 is a “high impact.” A point score of 200
to ˂300 is a “moderate impact. Many of the residences along West Mill and Cox Neck Road are within 50
feet of the road edge, and many are within 100 feet. Of the 21 historic structures identified in the DEIS
Acoustic Report along the Sound Avenue portion of the Project truck route, 9 are within 50 ft of the
roadway surface, and 10 are between 51 and 100 ft away (DEIS Appendix R, Acoustic Report Table 7).
Vibration Impacts to Quality of Life
As noted, the DEIS never meaningfully addresses the effects of construction-generated vibration on the
quality of life of residents near the Project site or along the Project haul truck routes. The DEIS concerns
itself almost exclusively with vibration impacts associated with potential property damage. However,
people are more sensitive in perceiving vibration than houses are to damage from vibration. “The
tolerance and reactions of humans to vibrations are important when standards are based on annoyance,
interference, work proficiency, and health.”23,24 These levels are significantly lower than the building
damage threshold levels employed in the GEMR and the Vibration Report, and stated in the DEIS, to
assess vibration impacts. According to FTA Guidelines:
“[J]ust like for noise, people annoyed by vibration may experience a variety of negative
responses, such as anger, disappointment, withdrawal, helplessness, depression,
anxiety, distraction, agitation, etc. Some public health experts feel that severe forms of
annoyance should be considered as a legitimate environmental issue affecting the well-
being and quality of life of the population exposed to environmental agents. Annoyance
turns out to be an issue that must be addressed.”25,26
“One of the challenges in developing suitable criteria for ground-borne vibration is that
there has been relatively little research into human response to vibration and,
specifically, human annoyance with building vibration. The American National Standards
23 US Bureau of Mine RI 8507, p.62. This is the same reference cited in the GEMR. Although it contains an extensive discussion
(pp. 62-68), with quantified data, on human response to vibration, this data was apparently not considered by preparers of
the GEMR and the DEIS.
24 One study found that “responses of ‘slightly perceptible’ occurred at 0.010 to 0.033 in/sec, and the threshold of ‘strongly
perceptible’ was 0.10 in/sec, all essentially independent of frequency over the range 4 to 25Hz.”24 Other studies (e.g.,
Goldman, cited in USBM 8507) (1948) support this. Goldman found "slightly perceptible" and "strongly perceptible"
(unpleasant) vibration PPV levels to be approximately 0.0086 and 0.074 in/sec, respectively.
25 Miedema HME, Janssen S and Kim R, Environmental noise and annoyance, in: Theakston, F., ed., Burden of disease from
environmental noise – Quantification of healthy life years lost in Europe (2011), World Health Organization Regional Office
for Europe, Copenhagen, 91-98.
26 Trollé, Arnaud, Catherine Marquis-Favre, and Étienne Parizet (2015), Perception and Annoyance Due to Vibrations in
Dwellings Generated from Ground Transportation: A Review, Journal of Low Frequency Noise, Vibration and Active Control
34(4):413-458.
Page | Vibration - 12 Rev9
Institute (ANSI) developed criteria for evaluation of human exposure to vibration in
buildings in 1983, and the International Organization for Standardization (ISO) adopted
similar criteria. . . ISO 2631-2 acknowledges that ‘human response to vibration in
buildings is very complex.’ It further indicates that the degree of annoyance cannot
always be explained by the magnitude of the vibration alone. In some cases, complaints
are associated with measured vibration that is lower than the perception threshold.
Other phenomena such as ground-borne noise, rattling, visual effects such as movement
of hanging objects, and time of day (e.g., late at night) all play some role in the response
of individuals. To understand and evaluate human response, which is often measured by
complaints, all of these related effects need to be considered (emphasis added)” (FTA
Guidelines p. 118)
Although the DEIS and the Vibration Report indicate numerous times that they relied on the FTA
Guidelines to prepare analyses of vibration impacts, they do not indicate that either the ISO or ANSI
standards referenced by the FTA were reviewed. Both documents have ignored the FTA’s concerns
regarding how vibration can impact quality of life because “annoyance cannot always be explained by
the magnitude of the vibration alone”.
Table 2 in the Vibration Report is entitled “Indoor Ground-Borne Vibration (GBV) Impact Criteria for
General Vibration Assessment from the FTA Guidelines.”27 Land Use Category 2 in that Table refers to
“Residences and buildings where people normally sleep.” GBV impact levels (VdB)28 in Category 2 are 72
for frequent events, 75 for occasional events, and 80 for infrequent events. According to the FTA
Guidelines “[I]mpact will occur if these levels are exceeded.” The Vibration Report states that “[F]or
evaluation of the criteria presented in Table 2 for impact to occupants, category 2 for residences with
frequent events will be used” (Vibration Report p.5). The report, following FTA Guidelines “define[s]
“frequent events as more than 70 events per day and occasional events as between 30-70 events per
day” It goes on to state that “[T]here will be up to, but no more than, 40 truck trips per day during
excavation, with a trip to and from the site. Consequently, the frequent events category is appropriate
and chosen since it would be worse case scenario.” This is incorrect and misleading.
The Vibration Report has followed the inappropriate practice in the DEIS of considering each round trip
by a Project haul truck as a single “event.” As the Planning Board has noted, each round trip is actually
two trips—one inbound and one outbound from the Project site.29 The true number of “events” per day
27 Table 2 is based on Table 6-3 in the FTA Guidelines.
28 vibration decibels (VdB)
29 As noted in comments on the Project’s traffic impacts, the Institute of Transportation Engineers defines a “trip” as a one-way
movement.
Page | Vibration - 13 Rev9
is, therefore, actually 80 30, qualifying the events as “frequent.” The appropriate GBV impact level
according to FTA Guidelines is, therefore, 72 VdB—not 75 VdB. This difference is significant.
Included in the Vibration Report is the discussion of a test that was made to collect vibration readings at
four locations from the passby of a truck equivalent to a loaded Project haul truck. Table 4 in the
Vibration Report indicates that at Location 4 (located on West Mill Road at the entrance to the Mill
Creek Preserve), trucks traveling south on West Mill Road generated a VdB of 74; truck traveling north
on West Mill Road generated a VdB of 73. Because the Vibration Report incorrectly classified the
frequency of trucks passing residences on West Mill Road as “occasional” it concluded that there would
be no impact (the VdB values of 74 and 73 are below the FTA Guidelines impact threshold of 75 for
occasional events). However, correctly classifying frequency of Project haul trucks passing residences as
“frequent” means that the impact threshold according to the FTA Guidelines is lowered to 72VdB, and
that vibration generated by Project haul trucks will exceed the impact threshold.31
The Vibration Report also discusses the potential for vibration from on-site construction equipment to
impact nearby residences. Table 8 in the Vibration Report lists the minimum distance (as calculated by
SoundSense)32 “recommended to meet indoor vibration levels”. Equipment generating the most
vibration include tub grinders, wood chippers and vibratory rollers33. The minimum distance to meet
recommended indoor vibration levels for these equipment types is 146 feet. The minimum distance for
bulldozers, excavators, and feller bunchers is 85 feet.
Table 9 in the Vibration Report includes the nearest distances to the construction site, and the distances
to the center of the construction site, for the three residences closest to the Project site. These
residences are 800 and 805 North Drive, and 5106 West Mill Road. According to the Vibration Report
the “nearest distances to the construction site” for these three residences are 175, 351 and 171 feet,
respectively. Based on these distances, the Vibration Report concludes that “[T]his indicates that there
will be no impact to nearby structures due to construction” (Vibration Report p.27). However, the very
next sentence qualifies this conclusion noting that “[T]here can be an increase in vibration levels due to
multiple pieces of construction equipment operating simultaneously” (emphasis added) (Vibration
Report p. 27). Given that it is highly unlikely that only a single piece of equipment will be operating at
30 Although it is likely that that the true number will be considerably higher (see comments on the Project’s traffic impacts).
31 There seems to be a disconnect between the ambient VdB values in Tables of the Vibration Report and the VdB values
recorded during the truck passby test. The former indicates the ambient VdB at Location 4 to be 74, yet the later indicates
that the VdB generated by a loaded Project haul truck would be lower at 73 VdB. This implies that the vibration generated by
the passing haul truck is actually lower than the ambient vibration.
32 SoundSense used the same equations (Equations 3 and 4) discussed above to calculate these distances. As also noted above,
one of these equations has been modified by SoundSense from the version in FTA Guidelines. This modification is based on
an questionable assumption about the nature of soils on the Project site.
33 Although vibratory rollers are not included in the equipment list in DEIS Appendix F, according to Appendix F they will be
employed during construction of the Project’s retaining wall.
Page | Vibration - 14 Rev9
any one time, the distances calculated by SoundSense do not reflect what real conditions will be during
construction.
Note that the language in the Vibration Report has been carefully worded to refer to “nearby
structures.” Both the DEIS and the Vibration Report are silent in regard to vibration impacts to
individuals outside, rather than inside, residences. The Vibration Report does not explain what it means
by “the construction site.” As measured from the Site Development Plans in DEIS Appendix C, 800 and
805 North Drive, and 5106 West Mill Road, actually abut the Project site. As measured from the Site
Development Plans the proposed retaining wall will be less than 100 feet from the 5106 West Mill Road
property line, and approximately 150 feet from the residential structure on that lot, and even closer to
the outside patio/pool area. These are all less than the 171 feet stated in the Vibration Report.
Both the DEIS and the Vibration Report fail to discuss potential vibration impacts to visitors to the West
Mill Preserve. The preserve abuts the Project site, and is approximately 100 feet from the location of
the Project’s proposed retaining wall. That construction which will require the use of vibratory rollers—
the equipment which generates the highest vibration levels.
FTA Guidelines34 state that 75 VdB is the approximate dividing line between barely perceptible and
distinctly perceptible vibration, and at 85 VdB vibrations are tolerable only at infrequent number of
events per day. Neither the Vibration Report nor the DEIS has indicated whether or not the 75 VdB level
will be exceeded at residences close to the Project site, at residence property lines, or at the West Mill
Preserve, when multiple pieces of construction equipment are operating simultaneously.
The conclusions in the DEIS and the Vibration Report (p.38) that “there are no vibration impacts
expected from soil excavation or construction activities” (DEIS p. 38), and that “[A]nalysis of the
construction equipment has shown that there is no predicted impact to any nearby neighbors’. . .”
(Vibration Report p.3) are not supported by the data provided.
Proposed Vibration Monitoring
Vibration monitoring proposed by the Applicant is not sufficient to protect property and residents
from construction-generated vibration impacts.
“To ensure that vibration is responsibly managed, the Applicant has committed to implementing a
vibration monitoring plan during construction at the Project Site to . . . ensure that ground-borne
vibrations are not a disturbance to nearby neighbors (DEIS pp. xxxi, xxxii, 296, 306; Vibration Report
p.3).”
34 FTA Guidelines, Table 5-5 “Human Response to Different Levels of Ground-Borne Vibration and Noise.”
Page | Vibration - 15 Rev9
The proposed monitoring plan includes the installation of monitoring terminals at three as yet
undetermined locations.35 “Exact vibration monitoring sites will not be determined until the vibration
monitors are installed based on accessibility to the exact monitoring sites” (p.27). According to the plan
“If vibration levels exceed permissible levels (based on the RMS Velocity [VdB]36 and Peak Particle
Velocity [PPV] the following steps will be taken for Vibration Monitoring at the three locations:
“• The acoustic consultant and construction management team should 37 be notified if an
exceedance is measured.
• The time and location of construction activities when the exceedance is measured are to be
provided to the acoustic consultant.
• If the exceedance is an RMS exceedance, the RMS velocity should be verified in the Syscom
ROCK’s cloud portal.
• Should the cause of the exceedance be linked to the construction activities, construction
should be halted immediately until appropriate measures, such as operating fewer pieces of
equipment or moving construction activities away from the construction area boundary, can
be completed.”
There are problems with this plan. First, the monitoring locations are not identified. However, Figure 13
in the Vibration Report does show possible locations. These possible locations all appear to be at the
Project site boundary, rather than at the closest sensitive receptors (residences and the Mill Road
Preserve). The number of monitoring locations, and their locations, should be determined by the
Planning Board, not left to the discretion of the Applicant.
Second, the threshold PPV for property damage, and threshold VdB for indoor impacts not have been
calculated. In addition, the VdB threshold is not a single value. Threshold values given in Table 2 of the
Vibration Report for indoor ground-borne vibration vary for residences from 72 VdB for frequent events,
to 75 for occasional events, and 80 for infrequent events. The monitoring plan requires that reference
maximum PPV and RMS (VdB) for individual pieces of equipment at the edge of the construction area be
calculated so that threshold vibration criteria can be calculated.
Third, given that much of the proposed construction activity (including the clearing and grubbing, and
excavation phases, as well as the construction phase) will involve mobile equipment, it will be very
35 A fourth terminal would be located the location of the Water Tower and Accessory Building at 3380 West Mill Road. The
water tower is a historic structure about which concern has been expressed by the NYS Office of Parks, Recreation and
Historic Preservation (OPRHP).
36 The RMS velocity is calculated in decibels relative to 1 micro-inch per second and is typically noted in VdB. In the Vibration
Report all VdB values are vibration levels in decibels with a reference quantity of 1 micro-in/sec.
37 Note the use of the word “should” rather than “shall.” This implies that the vibration monitoring plan that the Applicant has
committed to, may not be the plan recommended by SoundSense.
Page | Vibration - 16 Rev9
difficult to correlate a measured vibration exceedance with a particular piece of equipment operating at
a particular location at a particular time. The fact that multiple pieces of equipment are likely to be
operating simultaneously is an additional complication.
Fourth, the monitoring plan requires that a measured vibration exceedance be linked to construction
activities before any measures are taken to reduce vibration. No indication as to how long this might
take is provided. In the meantime, the activities generating the vibration will continue.
Finally, there is no way to know in advance that the “appropriate measures, such as operating fewer
pieces of equipment or moving construction activities away from the construction area boundary”
(Vibration Report p.30) would result in reducing vibration levels below the threshold criteria. The
monitoring plan is silent as to what additional measures might be available.
Page | Vibration - 17 Rev9
COMMENT FIGURE VIBRATION-1