3.6 NOISE Affected Environment. Noise Level Terminology and Human Hearing

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1 3.6 NOISE The following section provides a discussion of existing noise conditions on the BHTRP site and in the site vicinity, potential noise impacts from redevelopment under the Proposed Actions and Alternatives and measures to mitigate redevelopment-related noise impacts. This section is based on the Report (February 2009) prepared by Widener & Associates, Inc. The full report is included as Appendix H to this EIS. Shading indicates new or updated information provided subsequent to issuance of the Draft EIS. This analysis provides a quantitative estimate of traffic-related noise impacts (including vehicle and rail traffic) and a qualitative discussion of environmental (construction and operational) noise. Details about the basic methodology, equipment and modeling tools used to develop this analysis are provided in Appendix H Affected Environment Level Terminology and Human Hearing is defined as unwanted sound. In assessing the impact of noise upon the environment, the nature and level of activities that generate the noise, the pathway through which the noise travels, the sensitivity of the receptor, the period of exposure and the increase over the ambient noise levels are all considered. Sound level descriptors are ways of measuring and describing noise, including factors that account for sound duration, magnitude, frequency and pitch. Sound is measured in decibels (db), a logarithmic ratio between pressures caused by a given sound spectrum. Environmental noise is measured as A-weighted sound level in decibels, symbolized as db(a.) The A- weighted scale represents noise using the scale that corresponds closest to the range and characteristics of the human ear. Equivalent sound level (L eq ) is a common descriptor for measuring fluctuating sounds. The descriptor used to measure traffic-induced sound levels in this study is db(a) L eq (1h), which is defined as the equivalent A-weighted sound level over 1 hour. People generally cannot detect a change of 1 to 3 db(a). A change of 5 db(a) in a given noise source or environment would be likely to be perceived by most people under normal listening conditions. Table identifies sound levels of typical noise sources and activities (see Appendix H for further detail on noise level terminology). attenuation is logarithmic rather than linear. For example, a doubling of traffic volumes will result in a 3 db(a) increase in traffic-dominated noise environments. For line sources, such as streets, noise levels decrease by 3 to 5 db(a) for every doubling of distance from the source. For point sources, noise levels decrease more rapidly at approximately 6 db(a) for every doubling of distance from the source. Topography and the type of surface (paved or vegetated) on the site also play a role in noise attenuation characteristics. February

2 Table NOISE LEVELS OF REPRESENTATIVE SOUNDS Source Decibels Description Large rocket engine (nearby) Jet take-off (nearby) Pneumatic riveter Jet take-off (60 meters) Construction noise (3 meters) Subway train Heavy truck (15 meters) and Niagara Falls Average factory Normal conversation (1 meter) Quiet office Quiet Library Soft whisper (5 meters) Rustling leaves Normal breathing Pain threshold Constant exposure endangers hearing Very quiet Barely audible Hearing threshold 0 Source: Tipler, Regulatory Framework Traffic-related The Federal Highway Administration (FHWA) provides policies for state highway agencies in the Procedures for Abatement of Highway Traffic and Construction in the U.S. Code of Federal Regulations (23 CFR 772). These regulations pertain to traffic noise associated with new or improved transportation projects which receive federal funding. The Proposed Actions do not depend on federal funds and would not, therefore, be subject to these criteria; however, for the purposes of analysis in this EIS, these criteria were used as guidelines for demonstrating potential traffic noise impacts associated with the Proposed Actions. Table provides the FHWA Abatement criteria established by 23 CFR 772. FHWA guidance defines traffic noise impacts to occur when: Predicted traffic noise levels approach or exceed the noise abatement criteria; Predicted traffic noise levels substantially exceed the existing noise levels; or Predicted traffic noise levels are severe noise levels. As mandated by FHWA, the Washington State Department of Transportation (WSDOT) has established Abatement Criteria (NAC) that specify exterior traffic noise level limits for various land activity categories where frequent human use occurs, as presented in Table Individual states are delegated the responsibility to establish a definition of "approach", "substantially exceed" and "severe" in the FHWA 23 CFR 772 criteria (described above). WSDOT defines approach to be within 1 db(a) below the FHWA noise abatement criteria of 67 February

3 db(a) and defines substantially exceed to be a 10 db(a) increase over existing noise levels. A severe impact is defined as a 30 db(a) increase over existing levels or a level greater than 80 db(a) L eq (1h). Activity Category Table FEDERAL HIGHWAY ADMINISTRATION / WASHINGTON STATE DEPARTMENT OF TRANSPORTATION NOISE ABATEMENT CRITERIA L eq in dba A 57 (exterior) B 67 (exterior) C 72 (exterior) Description of Activity Category Lands on which serenity and quiet are of extraordinary significance and serve an important public need and where the preservation of those qualities is essential if the area is to continue to serve its intended purpose. Picnic areas, recreation areas, playgrounds, active sports areas, parks, residences, motels, hotels, schools, churches, libraries, and hospitals. Developed lands, properties, or activities not included in Categories A or B above. D Undeveloped lands. E 52 (interior) Residences, motels, hotels, public meeting rooms, schools, churches, libraries, hospitals, and auditoriums. Source: 23 C.F.R. Part 772 FHWA and WSDOT regulations characterize the effects of traffic noise based on whether noise levels approach (within 1 db(a) of the NAC) or exceed the NAC. For example, the exterior NAC for Category C (developed, industrial lands) is 72 db(a). An adverse effect from traffic noise would occur at these receivers according to FHWA/WSDOT regulations if anticipated exterior noise levels reach 70.5 db(a)l eq (1h) (within 1dB(A) of 72) or higher. For federally funded projects, a project is required to consider mitigation options when the proposed project meets or exceeds FHWA/WSDOT NAC regardless of whether or not the NAC were met or exceeded under the existing conditions. As mentioned above, the BHTRP is not receiving any federal funds and are not subject to FHWA traffic noise regulations; therefore, FHWA/WSDOT mitigation guidelines were taken into consideration as recommendations. Environmental This section discusses applicable noise regulations and agency guidelines which provide a basis for evaluating potential environmental noise impacts and mitigation or abatement for a proposed project. The Washington State regulations found in WAC establish three classes of environmental designations for noise abatement (EDNA), which are the areas or zones within which the maximum permissible noise levels are set. These EDNA zones are defined with respect to land usage and can usually be transferred to previously-established classifications in existing zoning ordinances or comprehensive plans. For example, industrial zoned properties are allowed higher noise emissions [70 db(a)] than residential areas [60 db(a)]. February

4 The City of Tacoma s noise ordinance takes a different approach and does not use decimal based standards. Instead, they use a flat rate to describe the maximum permissible increase in total sound level above ambient sound levels (See Table 3.6-3). Table CITY OF TACOMA "TABLE 2" MUNICIPAL CODE MAXIMUM PERMISSIBLE INCREASE IN TOTAL SOUND LEVEL ABOVE AMBIENT SOUND LEVEL 7:00am to 10:00pm 10:00pm to 7:00am Source: City of Tacoma, Outdoors 10 db(a) 5 db(a) "Impulsive sound, attributable to the source, which increases the total sound level by 15 db(a), or more above the ambient sound level, when there are less than 10 impulses per hour between the hours of 7:00am and 10:00pm, or less than four impulses within one hour between the hours of 10:00pm and 7:00am. If the number of impulses exceeds these limits, then Table 2 applies." Traffic on public roads, aircraft, and railroad traffic are exempt from the applicable environmental noise limits. Construction activities during daytime hours (7:00am- 9:00pm on weekdays and 9:00am- 9:00pm on the weekend) are also exempt from the noise regulations. In 1981, the United States Environmental Protection Agency (EPA) concluded that noise issues were best handled at the state or local government level and therefore has no regulations governing environmental noise. The EPA has, however, conducted extensive studies to identify the effects of sound levels on public health and welfare. The EPA Levels Document identifies sound levels requisite to protect the public health and welfare with an adequate margin of safety (EPA 1974). Because the cost or feasibility of achieving these sound levels was not taken into consideration, these levels are guidelines, not regulations or standards. EPA specifies an outdoor day-night sound level (Ldn) of 55 db(a) for areas where quiet is a basis for use. This is the same level as defined in WAC ; however, it cannot be compared with the City of Tacoma s ordinance because they do not specify decimal levels. The Department of Housing and Urban Development cites a maximum Ldn of 65 db(a) in residential areas (HUD 1985). This is also a policy and not a regulatory standard. Receivers and Methodology Existing conditions and proposed noise impacts were analyzed for two types of noise receivers on or in the vicinity of the BHTRP site: onsite and adjacent offsite traffic-related noise receivers, and environmental noise receivers such as onsite railroad noise receivers and offsite residential receivers to the east of the site. Traffic-related Receivers A total of 13 representative traffic noise receivers on and adjacent to the BHTRP site (see Figure 3.6-1) were selected for analysis. Receivers were chosen based on the following factors per WSDOT/FHWA guidance: February

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6 Proximity to the existing and proposed roadway. Sites most likely to be impacted by the Proposed Actions and Alternatives were favored. Location on the BHTRP site (project corridor). Receivers were selected along the length of the corridor, as well as within approximately 500 feet of the project corridor limits (500 feet from the north and south boundaries of the BHTRP site and 500 feet from the centerline of the primary proposed roadways). Primary area of outdoor use. Receivers were placed at sites where most outdoor use is likely to take place, such as sidewalks, parking lots, and other outdoor places where people might gather. Sites which would be removed as a result of the proposed project or which were too close to the roadway to model (within 6.5 feet) were not selected. All 13 receivers were modeled for the worst-case traffic noise condition in the BHTRP site (the PM peak hour) for existing conditions (2008) and full buildout at Worst-case scenarios were determined by analyzing traffic data provided in the Transportation Discipline Report (see Appendix K). For the 2013 traffic projections, traffic volumes were inflated at a rate of 2% per year until Synchro modeling conducted by David Evans and Associates, Inc. was used to obtain the PM peak hour traffic volumes. All of the 13 receivers are characterized as Activity Category C receivers (developed industrial land). For Category C receivers, the impact criterion is within one decibel of 72 db(a) or any measurement of 70.5 db(a) and above (refer to Table 3.6-2). Sound levels for the Existing 2008, Proposed Actions, Alternative 1 - Lincoln Overpass, 'Alternative 2 - Straight Overpass' and Alternative 3 - No Action conditions were derived from the Traffic Model 2.5, verified with field measurements, and for the purposes of this analysis, were compared with the FHWA/WSDOT standards and criteria. Sound level recording and modeling was undertaken in accordance with FHWA guidelines and standards. Additional information about methodology used in development of this traffic noise analysis is provided in Appendix H. Environmental Receivers Onsite Railroad Receivers from railroad operations can be a source of noise complaints and a key environmental concern. In order to assess the noise impacts from the proposed railroad improvements, the Federal Railroad Association (FRA) provides guidance on analyzing railroad noise. FRA s noise model CREATE was used to calculate the L eq in db(a) at 5 of the 13 traffic noise receivers (see Figure 3.6-2). Receivers thought to have the most (highest db(a) impacts were chosen. Receivers located in areas more than 500 feet away from any railroad tracks were not used. Additional information about methodology used in development of the railroad noise analysis is provided in Appendix H. February

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8 Offsite Residential Receivers A residential neighborhood is located on the bluff to the east of the BHTRP site, across the Hylebos Waterway. Due to the limitations of the traffic model utilized for this analysis (see Appendix H for details about the model), it is common practice to model receivers no farther away than 500 feet from each end of the site boundaries or more than 500 feet from the centerline of the proposed roadways. The residences to the east of the BHTRP site are beyond the 500 foot accepted limit (the closest residences are well over 1,000 feet from the proposed roadway changes) for this model to accurately estimate noise impacts from the BHTRP. Accordingly, different methodology was used to predict whether there would be any impacts to offsite residential properties to the east of the BHTRP site associated with construction or operations of the BHTRP. Ambient noise levels were taken at several locations in the residential areas located east of the BHTRP site in 2007 during pile-driving construction associated with an unrelated project on the Blair-Hylebos peninsula. Measurements were taken in accordance with the City of Tacoma s noise ordinance, to assess the potential for any significant impacts. No violations to the noise ordinance were observed. The type, frequency and location of the 2007 pile-driving activities would be similar to pile-driving activities assumed for the Proposed Actions. Refer to Appendix H for a map indicating the residential receiver locations. Existing Site Conditions The existing noise environment on the BHTRP site is consistent with that of an industrial marine port. The sources of noise emitted from shipping ports like the Port of Tacoma are varied, but generally include: large trucks, trains, cargo ship engines/generators, clanks and bangs from containers being on/off loaded, horns, and loudspeakers. All of these sources contribute to the overall noise level in and around the BHTRP area; however, traffic noise is the dominant source of noise on the BHTRP site in areas with the potential for outdoor human use. The potential for noise impacts on the BHTRP site would only occur in outdoor areas that are accessible to the public, such as sidewalks, bus stops, parking lots, and parks. Due to the highly developed and commercial nature of the BHTRP site, only a few areas exist on the site that have the potential for outdoor human use. Traffic-related Conditions Of the 13 receivers studied, only one receiver (Receiver 1) was present in a noise environment that met or exceeded the FHWA/WSDOT noise abatement criteria (NAC) under the existing conditions. All receivers in the site area are FHWA Category C receivers. Existing sound levels at all other Category C receivers ranged from 38.9 db(a) to 70.1 db(a), below the NAC of 71 db(a). Refer to Table for the results of existing noise levels modeled at all 13 receivers. Environmental Conditions Existing Onsite Railroad Conditions Of the five receivers modeled, sound levels ranged from 50 db(a) to 67 db(a) under existing conditions (see Table 3.6-6). The noise levels experienced at receivers resulting from railroad February

9 noise are within the same range as the traffic noise levels experienced at the receivers. None of the receivers modeled shows a violation of the FHWA/WSDOT NAC s under existing conditions. Existing Offsite Residential Ambient Conditions Ambient noise levels were taken at several locations in the residential areas located to the east of the BHTRP site in 2007 during pile-driving and construction associated with an unrelated project on the Blair-Hylebos peninsula. Measurements were taken in accordance with the City of Tacoma s noise ordinance, to assess the potential for any significant impacts. No violations to the City's noise ordinance were observed. The type, frequency and location of these 2007 pile-driving activities would be similar to pile-driving activities assumed for the Proposed Actions Impacts Redevelopment of the BHTRP site would result in the generation of noise during both construction and operational phases of the Proposed Actions and Alternatives. from the construction phase would be intermittent and would vary considerably depending on the specific nature of the construction, with some activities having a short duration and others a longer duration. This intermittent noise generation would occur over the assumed buildout period. Both construction and operational noise are analyzed below. The noise impact analysis methodology, including models and equipment used, are described in detail in Appendix H Construction The Proposed Actions and Alternatives would have similar ongoing phased construction activities over the buildout period including pile-driving, jackhammering, grading, excavating, demolition, soil and material supply delivery, and heavy equipment use; therefore, construction activities are assumed to be generally similar for the Proposed Actions and Alternatives. The maximum noise level ranges for various pieces of construction equipment at a distance of 50 feet are depicted in Table The maximum noise levels at 50 feet would range from approximately 70 to 105 db(a) for the type equipment anticipated for use on the BHTRP site. Based on WSDOT guidance, short-term noise impacts would be expected to radiate up to a maximum of one mile from the BHTRP site, as point sources of sound lose approximately 6 db(a) for every doubling of distance. At the distance of one mile, the pile-driving noise would not be distinguishable over other ambient sounds. Construction activities associated with the BHRTP would be anticipated to produce the largest change in the noise environment; however, this change is only temporary. During construction, machinery producing loud sounds such as piledrivers would be in use and additional trucks and equipment would be running in the BHTRP area. The ambient noise measurements taken in the residential neighborhood to the east of the BHTRP during the 2007 construction activities of the separate project (including the use of equipment such as pile-driving), would be anticipated to be similar to the noise levels anticipated during construction activities associated with the Proposed Actions (including regularly occurring Port operational noises present in the background). Construction is anticipated to provide the worst case noise scenario, because not February

10 only would equipment producing the loudest sounds such as piledrivers be in use, but the cumulative ambient noises expected from ongoing Port operations are factored into the noise environment as well. The 2007 noise measurements taken in the residential area to the east (which were taken consistent with the City of Tacoma Ordinance) reflecting construction activity associated with a separate project that included pile-driving, indicated no violations of the Tacoma Ordinance. Because construction activities under the Proposed Actions would be similar in nature to those measured in association with the 2007 project, violations of the Tacoma Ordinance would not be anticipated in the residential neighborhoods to the east during construction activities associated with the Proposed Actions. Once construction of the BHTRP is complete, the ambient noise environment surrounding the Port would be anticipated to decrease. Table TYPICAL CONSTRUCTION EQUIPMENT NOISE LEVELS Level (dba) at 15 meters (50 ft.) Compactors (rollers) Front-end loaders Earth Moving Backhoes Tractors Scrapers, graders Equipment Type Other Impact Stationary Materials Handling Pavers Trucks Concrete mixers Concrete pumps Cranes (movable) Cranes (derrick) Pumps Generators Compressors Pneumatic wrenches Jack hammers, rock drills Pile drivers (peaks) Vibrator Saws Source: EPA, 1971 and WSDOT, February

11 Impacts on receivers as a result of construction noise would be minimized by: The Port does not plan on working outside of the window set forth by the City of Tacoma s noise ordinance, (#27673, Chapter ); however, should there be a need for after-hours construction, a variance would be obtained in accordance with local and state regulations. Operating all motorized equipment used in construction and demolition with a muffler. Utilizing the best available noise abatement technology on construction equipment Operations The onsite noise environment after the construction of the Proposed Actions and Alternatives would not be anticipated to change significantly from existing conditions as similar marine port operations would continue, such as: large trucks, trains, cranes on/off loading containers, loudspeakers, and horns. Below is a comparison of anticipated noise impacts (onsite traffic noise, onsite railroad noise and offsite residential ambient noise) under the Proposed Actions and Alternatives 1, 2 and 3. Proposed Actions Traffic-related The Proposed Actions assume substantial changes to the roadway system on the BHTRP site. The traffic changes associated with the Proposed Actions would effect receptors located in outdoor areas accessible to the public at full buildout. One receiver (Receiver 1), which exceeds the FHWA/WSDOT NAC under existing conditions, exceeded the NAC under the Proposed Action. The maximum sound level anticipated under the Proposed Actions would be 75.6 db(a) at Receiver 1. See Table for a list of noise levels anticipated under the Proposed Actions in 2013 at all 13 traffic noise receiver locations. Although not exceeding the FHWA/WSDOT NAC, four of the receivers were found to exceed the FHWA/WSDOT criteria under the Proposed Actions, with increases of at least 10 db(a) over existing conditions: Receiver 3 exceeded the criteria with an increase of 14.6 db(a); Receiver 5 exceeded the criteria with an increase of 17.7 db(a); Receiver 8 exceeded the criteria with an increase of 12.6 db(a); and Receiver 13 exceeded the criteria with an increase of 11.6 db(a). As indicated earlier in this section, the FHWA/WSDOT criteria are not directly applicable to the Proposed Actions and are used as guidelines for assessing noise associated with vehicle traffic. It should also be noted that none of the locations identified as exceeding FHWA/WSDOT criteria represent noise sensitive locations such as schools or residences and are reflective of a busy industrial area; for example, Receiver 1 is a bus stop near an intersection accommodating February

12 heavy trucks. The traffic noise associated with the Proposed Actions would represent a continuation of the existing noise environment and would not be anticipated to result in significant impacts. Table SUMMARY OF CALIBRATED RESULTS FOR THE EXISTING CONDITIONS, PROPOSED ACTIONS AND ALTERNATIVES # Receiver Name Existing Conditions (2008) L eq 1hr Proposed Actions (2013) L eq 1hr Alt. 1 - Lincoln Overpass (2013) L eq 1hr Alt. 2 Straight Overpass (2013) L eq 1hr Alt. 3 No Build (2013) L eq 1hr Impact Approach Level Criteria Impact Substantial Increase Criteria 1 BPA Bus Stop Buffelen Marina S. of E. 11th St., W of Taylor 5 S. of E. 11th St., E. of Taylor E. of Taylor btw Lincoln and E. 11th 7 Carlile Arkema W. of Taylor btw SR and Lincoln 10 Glacier Entrance Taylor Overpass SR 509/Taylor sidewalk 13 Access Rd. Parking Lot Source: Widener & Associates, 2008 All sound levels are measured in A-weighted decibels (dba). -NAC s exceeded -Substantial increase -Both NAC exceeded and a substantial increase Environmental Railroad - The Proposed Actions assume substantial modifications to the existing railroad system on the BHTRP site. At full buildout in 2013, the Proposed Actions assume expanded railroad operations. Modeling has shown that sound levels from the railroad improvements assumed under the Proposed Actions have the potential to increase sound levels at the identified receivers by a maximum of 3 db(a), or a level that is barely perceptible to the human ear. The improvements to the railroad system would not be anticipated to cause any modeled receivers to reach levels above the FHWA/WSDOT NAC criteria. Under the Proposed Actions, noise levels associated with railroad activities ranged from 61 db(a) to 68 db(a). See Table for the assumed noise levels at each receptor under the Proposed Actions. The noise levels experienced at receivers resulting from railroad noise are within the same range as the traffic noise levels experienced at the same receivers. Using decibel addition, two February

13 sources of noise can be added together for an estimate of the total noise perceived at a given receiver. As indicated in Table 3.6-6, with the combined noise associated with traffic and rail operations, none of the receivers modeled shows a violation of the FHWA/WSDOT NAC s. Refer to Appendix H for model outputs. Table PERCEIVED COMBINED TRAFFIC AND RAILROAD DB(A) LEVELS AT MODELED RECEPTORS Existing Existing Existing Proposed Proposed Rail Traffic Total Rail Traffic db(a) Receiver Description 6- E. of Taylor btw Lincoln and E. 11th Akrema W. of Taylor btw SR 509 and Lincoln Glacier Entrance Access Rd. Parking Lot Source: Widener & Associates, Total db(a) Offsite Residential Ambient - level measurements were taken at various locations in the neighborhood to the east of the BHTRP site during a previous construction and piledriving project in measurements were taken with and without pile-driving activity. These procedures for determining sound levels are consistent with the City of Tacoma's Ordinance, Section Refer to the tables and receiver map in Appendix H for the noise level data and location of the receiver sites. Based on the results of the 2007 noise measurements and field notes, the pile-driving noise did not significantly change the ambient sound levels. Sound levels in the neighborhood during these activities ranged from 54 db(a) to 66 db(a). Generally, there was an increase of 2-4 db(a) over ambient noise levels in locations when pile-driving was known to be occurring. An increase of 2-4 db(a) over existing conditions does not violate the maximum permissible increase in total sound level above ambient sound level as set forth in the City of Tacoma s Municipal Code. There were some instances where the ambient level (L eq ) was lower when pile-driving was occurring than when pile-driving was not occurring. This suggests that there are other factors affecting the noise levels in the areas surrounding the BHTRP site. Many of the measurement locations were located next to busy streets, where the traffic noise was apparent. Because the offsite residential ambient noise environment under operations of the Proposed Actions would be anticipated to be similar to or lower than the noise conditions measured during construction of this separate project (which did not include significant noise increases), significant noise impacts to the offsite residential area during operation of the Proposed Actions would not be anticipated. February

14 Alternative 1 - Lincoln Overpass Traffic-related Alternative 1 assumes a similar road network to the Proposed Actions except for the assumption of a Taylor Way overpass near Lincoln Avenue and no Taylor Way overpass near SR 509. The roadway improvements associated with Alternative 1 would result in two receivers (Receiver 1 and Receiver 5) approaching or exceeding the FHWA/WSDOT NAC. See Table for a list of noise levels anticipated under Alternative 1 at all 13 traffic noise receiver locations. Although not exceeding the FHWA/WSDOT NAC, three of the receivers were found to exceed the FHWA/WSDOT criteria under Alternative 1, with increases of at least 10 db(a) over existing conditions: Receiver 3 exceeded the criteria with an increase of 14.6 db(a); Receiver 5 exceeded the criteria with an increase of 19.5 db(a); and Receiver 8 exceeded the criteria with an increase of 14 db(a). As described for the Proposed Actions, the traffic noise impacts associated with Alternative 1 would not be significant contributions to the existing noise environment. Environmental Onsite Railroad - Railroad improvements under Alternative 1 would be similar to the Proposed Actions and significant impacts would not be anticipated. Offsite Residential Ambient - Offsite residential ambient noise levels in the neighborhood to the east of the BHTRP would be assumed to be similar to the Proposed Actions and significant impacts would not be anticipated. Alternative 2 - Straight Overpass Under Alternative 2, the Straight Overpass Alternative, the proposed roadway alignment and traffic volumes would be similar to the Proposed Actions with the exception of the changes in orientation to the Taylor Way overpass. Therefore, it is assumed that receivers would experience similar noise levels to those under the Proposed Actions. Alternative 3 - No Action Traffic-related Under the No Action Alternative, less roadway improvements are assumed than under the Proposed Actions and lower traffic volumes are expected. A barely perceptible 2.3 db(a) increase in noise levels over existing conditions would be anticipated under this Alternative with the maximum sound level experienced at 72.6 db(a) at Receiver 1. Only one receiver (Receiver 1), which currently exceeds the FHWA/WSDOT NAC, exceeded the FHWA/WSDOT February

15 NAC under Alternative 3. See Table for a list of noise levels anticipated under the Alternative 3 at all 13 traffic noise receiver locations. Although not exceeding the FHWA/WSDOT NAC, one receiver was found to exceed the FHWA/WSDOT criteria under Alternative 3, with increases of at least 10 db(a) over existing conditions: Receiver 3 exceeded the criteria with an increase of 10.2 db(a) The traffic noise impacts associated with Alternative 3 would not be significant contributions to the existing Port noise environment. Environmental Railroad - Only minor railroad improvements are assumed under the No Action Alternative. Rail noise levels under this Alternative are assumed to be similar to existing conditions (see Table 3.6-6). Residential Ambient - Residential ambient noise levels would be assumed to be similar to the Proposed Actions Mitigation Measures Construction The Port does not plan to perform construction activities outside of the time window set forth by the City of Tacoma s Ordinance, (#27673, Chapter ) which limits work between 9pm and 7am on weekdays; and between 9pm and 9am on Saturdays, Sundays, and legal holidays, however, should there be a need for after-hours construction, a variance would be obtained in accordance with local and state regulations. However, the following techniques could be utilized to reduce the noise impacts for people passing by the construction area: Minimize construction noise by turning off engines when not in use. Back up alarms can produce some objectionable sound, although they are exempt from the Washington State noise ordinance. It is recommended that vehicles drive forward as much as possible to avoid the use of the back-up alarm. Substitute hydraulic or electric models for impact tools such as rock drills or jackhammers, when feasible. Operations Traffic-related As discussed in Section 3.6.1, the FHWA/WSDOT regulations regarding traffic noise impact analysis and mitigation requirements do not apply to the BHTRP since this project is not receiving federal funding. FHWA and WSDOT guidelines were used as recommendations to provide impact guidelines for the analysis as well as for mitigation. The FHWA/WSDOT February

16 mitigation analysis is not required; however, for lack of better guidance, and to ensure mitigation options are considered, the following evaluation was conducted: FHWA/ WSDOT require federally funded projects to consider mitigation options when the proposed project meets or exceeds FHWA / WSDOT criteria and/or standards regardless of whether or not the criteria and/or standards were met or exceeded under the existing conditions. Mitigation measures were fully evaluated in accordance with FHWA and WSDOT noise abatement policy for receivers that would be impacted by the Proposed Actions. FHWA/WSDOT guidelines recommend that the following types of abatement be considered and evaluated for reasonableness and feasibility : Traffic management measures (e.g. traffic control devices and signing for prohibition of certain vehicle types, time-use restrictions for certain vehicle types, and modified speed limits); Change of alignment either vertical or horizontal; Construction of noise barriers; Acquisition of property; or, insulation. Feasibility deals primarily with engineering considerations such as whether or not a substantial reduction in sound levels can be achieved and whether or not abatement measures would affect property access. Reasonableness assesses the practicality of the abatement measures including: cost, the amount of noise reduction, and future traffic levels. Because there are no residences in the project corridor, the WSDOT noise mitigation cost per residence is not applicable. The following section discusses the reasonableness and feasibility of each of the five recommended abatement measures in regard to the Proposed Actions and Alternatives. Traffic Management Measures - Because the proposed roadway improvements are intended to improve efficiency for a new shipping container terminal and relocated terminal, it is not reasonable to prohibit or put time-use restrictions on certain vehicle types due to the nature of vehicles associated with a shipping port. The City's policy on setting speed limits is consistent with Washington State s basic speed law which is based on safety and operations, and follows the 85th percentile rule (the speed at which 85 percent of the traffic is moving (RCW )). According to the FHWA, studies have shown crash rates are lowest at around the 85th percentile speed. Vehicles traveling significantly faster or slower than this speed are at a greater risk for being involved in a crash, as large variations in speed within the traffic stream create more conflicts and passing maneuvers. About a 20 mph (33 km) reduction in speed is necessary for a noticeable decrease in noise levels. Lowering the speed limit to the degree necessary to accomplish a noticeable decrease in noise levels would compromise safety; thus, is not considered to be a reasonable abatement option. Change of Alignment Either Vertical or Horizontal - The BHTRP site is within an urban corridor which is highly developed and zoned for industrial uses. Changing the horizontal alignment would shift impacts rather than eliminate them, and would create additional design problems February

17 and impacts due to limited space on the peninsula. The proposed vertical alignment is level. Although depressing the roadway would reduce noise impacts, it would be cost prohibitive. This abatement measure is not considered to be either feasible or reasonable. Construction of Barriers - All of the receivers affected by the project are Category C receivers (developed industrial lands). There are no residences within the project area that would benefit from the construction of a noise barrier. This abatement measure is not considered to be either feasible or reasonable. Acquisition and Vacating of Property - This mitigation measure does not apply since there are no residences in the project area to acquire. This abatement measure is not feasible. Abatement - None of the abatement options discussed above are considered to be reasonable and feasible by FHWA/WSDOT standards. Therefore, noise abatement is not recommended as mitigation for noise level increases above threshold limits generated by the Proposed Actions or Alternatives. Environmental Onsite Railroad - No impacts to the onsite railroad noise environment are anticipated; therefore, no mitigation is proposed. Offsite Residential Ambient - No impacts to the offsite residential ambient noise environment are anticipated; therefore, no mitigation is proposed Significant Unavoidable Adverse Impacts Traffic associated with the Proposed Actions would increase the noise level at outdoor locations on the BHTRP site and in the immediate vicinity. Using the FHWA/WSDOT noise abatement criteria as a guideline to quantify noise impacts 1, the analysis indicates that noise levels above the FHWA/WSDOT noise abatement criteria would continue at one receiver location and would substantially exceed the increase over existing levels at four receivers. None of the receiver locations identified as exceeding FHWA/WSDOT criteria represent noise sensitive uses such as schools or residences, and are reflective of a busy industrial area. The traffic noise associated with the Proposed Actions would represent a continuation of the existing noise environment and would not be anticipated to result in significant impacts. 1 The FHWA noise abatement criteria are required for federally-funded roadway projects and are utilized in this EIS for guidance only. February