3.8 NOISE AND VIBRATION

Transcription

1 Final Environmental Evaluation 3.8 NOISE AND VIBRATION Introduction to Analysis Summary of Results Prior to implementation of mitigation, the Preferred Alternative would result in both severe and moderate noise impacts at multiple residences and institutional uses (museums, hospitals, day care centers, etc.) along the Northwest Rail (NWR) Corridor. The summary of severe and moderate impacts is provided in Table 3.8- below. The noise analysis accounted for all stations that are part of the Preferred Alternative. However, because only seven of these stations are currently funded though the FasTracks program, the analysis also examined a scenario with only the seven funded stations for comparison. Therefore, both scenarios (FasTracks-only and all-stations) are presented in this analysis. impacts differ between the two scenarios because the effects of Diesel Multiple Unit (DMU) speed and throttle profile effects near the additional stations. The 4 st Avenue East and Pecos stations are part of the Gold Line project. Analysis of these stations is included in the Gold Line Final Environmental Impact Statement (Federal Transit Administration [FTA] 29). TABLE SUMMARY OF NOISE IMPACTS (WITHOUT MITIGATION) Severe Preferred Alternative FasTracks Only (7 stations) Preferred Alternative All Stations ( stations) Residential Institutional Total Severe Moderate Residential 922,67,35,3 (Lower 5%) Institutional 2 2 Moderate Residential (Upper 5%) Institutional Total Moderate,275,58,384,52 Source: NWR Corridor Project Team, 29. It is predicted that all of the severe noise impacts would be mitigated (under either station scenario) by implementing Quiet Zones to eliminate train horn noise at select crossings between West 64 th Avenue to State Highway (SH) 9. Because implementation of Quiet Zones would eliminate horn noise from existing freight train operations (as well as from future commuter rail operations) the total horn noise exposure along the Quiet Zones would be significantly reduced. Additionally, the Quiet Zones would be supplemented by noise barriers at three locations along the NWR Corridor. It is expected that residual moderate noise impacts would remain in 235 following the implementation of the Quiet Zones and noise 3.8- May 2

2 Final Environmental Evaluation barrier mitigation measures. The majority of these residual moderate impacts occur where mitigation measures have lowered previously severe impacts to the moderate level. However, the residual moderate impacts in 235 would be limited to 235 residences for the all-stations scenario and to 89 residences for the FasTracks-only scenario. Moderate noise impacts in 235 would also remain at four institutional uses under both the station scenarios. The roadway and transit projects included in the No Action Alternative would likely result in noise impacts. The location and severity of noise impacts resulting from these projects will be addressed in the environmental documentation prepared for the individual projects as they are funded. Purpose assessments are key elements of the environmental impact assessment process for transit projects. Additionally, noise is one of the principal environmental impacts associated with rail transit projects and has been defined as a public issue throughout the NWR Corridor public involvement process Affected Environment impacts are determined for three categories of sensitive land uses: Category Buildings or areas where quiet is an essential element of their purpose. Category 2 Residences and buildings where people normally sleep, such as hospitals and hotels. Category 3 Institutional land uses with primarily daytime and evening use, such as schools, libraries, churches, and parks. The basic unit of measure for community noise impact analysis is the A-weighted sound level in decibels (dba), which describes the noise at a given location at any moment in time. Most commonly encountered outdoor noise sources generate sound levels within the range of 6 dba to 9 dba at a distance of 5 feet. 2 The A-weighted sound level metrics most commonly used to express noise exposure over extended periods of time are the Hourly Equivalent Sound Level [Leq(h)] and the Day-Night Sound Level (Ldn). The Leq(h) measure describes the cumulative exposure experienced at a location from all noise-producing events over a -hour period. The Ldn is a weighted noise level over a 24-hour period that takes into account the increased sensitivity to noise at night, when most people are asleep. In terms of Ldn, the ideal residential noise goal is 55 dba according to United States Environmental Protection Agency, with more common conditions ranging from 6 to 65 dba. Due to existing freight traffic of five to seven movements per day, current Ldn levels at the sensitive land uses closest to the track in the project study area have been found to range FTA Transit and Vibration Impact Assessment, Final Report FTA-VA May For example, a lawn mower is typically measured at 72 dba, an air conditioner at 62 dba, and a jack hammer at 86 dba. May

3 Final Environmental Evaluation between 6 dba and 8 dba. Freight operations occur throughout all sections of the NWR Corridor. -sensitive land uses are described below. Denver Section -sensitive land uses are situated in four areas to the north of downtown Denver. The first area is bounded by 2 th Street to the southwest, Delgany Street to the southeast, 23 rd Street to the northeast, and the BNSF Railway Company railroad tracks to the northwest. This area includes a number of four-story residential loft buildings mixed with industrial and commercial properties. The existing noise levels in this area are relatively high due to nearby railroad operations and local street traffic. The second area is located to the east of the proposed alignment south of Interstate 25 (I-25), near Park Avenue West and Globeville Road. This area includes the Railyard Marketplace affordable apartment complex and the La Quinta Inn hotel. The existing noise levels in this area are affected by both road and rail traffic. The third area is located to the west of the proposed alignment along Inca Street between I-25 and I-7. This area primarily includes single family homes, most of which are located south of 38 th Avenue where the existing noise levels are dominated by nearby highway and railroad traffic. Finally, the fourth area is located to the east of the proposed alignment, north of I-25 along Fox Street. The land use in this area is mostly commercial, with a motel and a small number of residences mixed in. The area currently experiences noise from the existing freight train traffic as well as adjacent roadway noise. Adams Section Freight trains dominate the noise exposure in areas close to the existing track along this section of the proposed alignment. Except for locations near major roadways, the background noise from sources other than trains is relatively low. Between West 64 th Avenue and Lowell Boulevard, there is a low-density residential area with single- and two-family homes located as close as 5 feet to feet from the track. Because these homes are not near grade crossings, train noise exposure is more limited than in the area of Westminster between W. 72 nd Avenue and Sheridan Boulevard where the track passes through heavily populated residential areas with several at-grade crossings. Other sensitive receptors in this area include the Bowles House Museum (historically associated with the rail line), the Harris Park Elementary School, and the Arapahoe House rehabilitation hospital. Westminster Section This section of the alignment traverses populated areas in the City of Westminster as well as the northeast border of the City of Arvada and an unincorporated area of Jefferson County. Freight trains dominate the noise exposure at locations close to the existing track and, except near major roadways, the background noise from other sources is relatively low. The rail alignment in this area includes both cut and embankment sections that have some affect on the existing noise levels at nearby receptors, and noise from train horns is limited to locations near two grade crossings. Broomfield Section -sensitive receptors near the existing track along this section of the proposed alignment are limited to residences in the vicinity of the West 2 th Avenue grade crossing. The closest residences in this area are in a densely populated mobile home park within 5 feet of the tracks to the south of West 2 th Avenue, and to the north, Habitat for Humanity homes are May 2

4 Final Environmental Evaluation located adjacent to the track. Excluding trains, the background noise in this area is dominated by traffic on United States Highway (US) 287. Louisville Section Freight trains dominate the noise exposure in areas close to the existing track along this section, and the background noise from other sources is quite low. At the southern end of this section in Broomfield, there is a large new development of condominiums and townhomes located to the west of the alignment near the proposed Flatiron Station, with plans for hotel development on adjacent parcels. In downtown Louisville, there are a number of residences as close as 5 feet from the tracks. This area also contains a park and Louisville Middle School. Due to the many grade crossings, freight train horn noise dominates the existing noise exposure in this vicinity. North of downtown, between South Boulder Road and Baseline Road, the existing track is on an embankment. In this area, there are many homes located about 2 feet west of the track, along with two day care centers (Bright Horizons Family Solutions and La Petite Academy) and the Patchwork School (planned opening in Fall 2). Boulder Section -sensitive receptors near the existing track in Boulder include residences, the Courtyard by Marriott hotel, one school (Naropa University), and two day care facilities (the University Corporation for Atmospheric Research [UCAR] Child Care Center and the Family Learning Center). The residential areas include country homes in Boulder County and multifamily homes in the City of Boulder. The existing noise exposure is generally dominated by freight trains and is highest at receptors near grade crossings. Excluding trains, the background noise varies with location and is highest near Foothills Parkway and other major roadways. Longmont Section Along this section, noise-sensitive land use is primarily concentrated in Niwot where there are a number of single-family residences located to the east of the proposed alignment. The dominant noise sources in this area are freight trains and SH 9 traffic. North of Ken Pratt Boulevard, the proposed alignment diverges from SH 9 and there is one residential area (the St. Vrain Village Mobile Home Park) located adjacent to the tracks along Price Road. In addition to these residential areas, noise-sensitive receptors along this section include Front Range Community College located near the North 95 th Street grade crossing. Measured Levels To characterize the existing baseline noise conditions at sensitive receptors along the proposed alignment, a field measurement program was conducted at 2 long-term sites (24 to 36 hour unattended measurements were taken) and six short-term sites (-hour observed measurements were taken) sites during the week of March 6 through March 2, 29. These results were supplemented by noise data obtained at five additional sites in the Denver Section for other Regional Transportation District (RTD) projects. The general locations of these measurement sites are indicated in Figure 3.8- and the results are summarized in Table May

5 Final Environmental Evaluation FIGURE EXISTING BASELINE NOISE MEASUREMENT LOCATIONS ALONG THE NWR CORRIDOR ALIGNMENT Sources: Colorado Department of Transportation (CDOT), 26; Denver Regional Council of Governments (DRCOG) 27-8; ESRI SDC 24; NWR Corridor Project Team May 2

6 Final Environmental Evaluation TABLE SUMMARY OF EXISTING AMBIENT NOISE MEASUREMENT RESULTS Site Number LT-A LT-B LT-C LT-D LT- LT-2 LT-3 LT-4 LT-5 LT-6 LT-7 LT-8 LT-9 LT- Measurement Location Description 3 Huron Street Denver (residential loft) 3735 Inca Street Denver (single-family residence) La Quinta Inn Denver (hotel) 393 Fox Street Denver (single-family residence) 259 W. 66 th Place Denver, Adams Co. (duplex residence) 82 Tennyson Street Westminster (single-family residence) 983 Zephyr Drive Westminster, Adams Co. (single-family residence) Broomfield Mobile Home Park, Unit #34 Broomfield 342 Via Varra Broomfield (The Flats & Townes at Vantage Point) 435 Front Street Louisville (single-family residence) 2464 Evans Avenue Louisville (single-family home) 3265 Foundry Place, Unit #7 Boulder (Steelyards mixed development) 3865B Talisman Place Boulder (townhome) 5577 Pioneer Road Juhl, Boulder County (single-family residence) Distance from BNSF Start of Measurement Railway Company Track (feet) Date Time May Measurement Duration Outdoor Exposure Measured with Trains Ldn (dba) Estimated Without Trains Leq (dba) 7 8/6/27 6: 24 hours NA 275 2/25/24 7: 24 hours NA 67 8/2/28 5: 24 hours NA 6 2//25 3: 24 hours NA 75 3/6/29 : 24 hours 6 52 NA 75 3/6/29 : 24 hours NA 7 3/6/29 2: 24 hours 6 55 NA 5 3/6/29 2: 24 hours 7 57 NA 4 3/9/29 : 24 hours NA 7 3/7/29 4: 24 hours 8 53 NA 5 3/7/29 5: 24 hours NA 325 3/9/29 : 24 hours NA 25 3/7/29 5: 24 hours 73 6 NA 2 3/7/29 6: 24 hours NA

7 Final Environmental Evaluation TABLE SUMMARY OF EXISTING AMBIENT NOISE MEASUREMENT RESULTS Site Number LT- LT-2 ST-A Measurement Location Description 33 Murray Street Niwot (single-family home) 47 Forbes Court Longmont (St. Vrain Village Mobile Home Park) 22 Delgany Street Denver (residential loft) Distance from BNSF Start of Measurement Railway Company Track (feet) Date Time Measurement Duration Outdoor Exposure Measured with Trains Ldn (dba) Estimated Without Trains Leq (dba) 8 3/8/29 9: 36 hours NA 25 3/8/29 9: 36 hours NA 35 8/7/27 4:35 75 minutes NA NA 63 ST- Bowles House Museum Westminster 3/6/29 5:35 6 minutes NA NA 57 ST-2 ST-3 Harris Park Elementary School Westminster Naropa University Nalanda Campus Boulder 3/6/29 3:5 6 minutes NA NA /7/29 6:5 6 minutes NA NA 55 ST-4 UCAR Child Care Center Boulder 7 3/8/29 :45 6 minutes NA NA 53 ST-5 Family Learning Center Boulder 5 3/8/29 9:55 6 minutes NA NA 53 ST-6 Front Range Community College Longmont Source: NWR Corridor Project Team, 29. Notes: NA = Not applicable 3/9/29 :3 6 minutes NA NA May 2

8 Final Environmental Evaluation Characterization of the Existing Environment Considering the non-scheduled nature and consequent daily variation of freight train operations, and the fact that the measurement results represent only a -day sample of current train noise at a set of finite locations along the NWR Corridor, modeling of the existing freight train noise provides the most uniform approach for defining baseline noise conditions. This was accomplished by using Federal Railroad Administration (FRA) methodology to model the existing freight train noise exposure at each noise-sensitive receptor or receptor group based on distance and shielding from the track. The total existing noise exposures at locations along the rail corridor were determined by combining the estimated train noise with the background ambient noise from other sources (e.g. road traffic, aircraft, and general neighborhood activities) obtained from the noise measurements. The resulting noise levels were then used as the baseline for evaluation of noise impact from the proposed commuter rail operations Impact Evaluation The noise impact evaluation for the Preferred Alternative addresses the effects of NWR Corridor commuter rail service only. The assessment of cumulative noise impact includes the effects of all these sources along the alignment. impact methodology, results, and mitigation are discussed below. Methodology impact for the NWR Corridor is based on criteria defined in the FTA guidance manual, Transit and Vibration Impact Assessment (FTA 26). While FTA is not the lead agency for this project, FTA guidance is the most relevant guidance addressing transit noise and vibration. FTA defines two levels of impact (refer to Figure 3.8-2): Severe Impact Project-generated noise in the severe impact range can be expected to cause a significant percentage of people to be highly annoyed by the new noise and represents the most compelling need for mitigation. mitigation will normally be specified for severe impact areas unless there are truly extenuating circumstances that prevent it. Moderate Impact In this range of noise impact, the change in the cumulative noise level is noticeable to most people but may not be sufficient to cause strong, adverse reactions from the community. In this transitional area, other project-specific factors must be considered to determine the magnitude of the impact and the need for mitigation. These factors include the existing noise level, the predicted level of increase over existing noise levels, the types and numbers of noise-sensitive land uses affected, the noise sensitivity of the properties, the effectiveness of the mitigation measures, community views, and the cost of mitigating noise to more acceptable levels. May

9 Final Environmental Evaluation FIGURE FTA NOISE IMPACT CRITERIA Source: FTA, 26. modeling assumed that freight traffic would continue within the rail corridor at frequencies and operating times similar to today. Freight trains would be able to operate in between commuter rail trains during off-peak times. Commuter train noise levels were projected based on current FasTracks operations plans and the prediction models from the FTA guidance manual, assuming that NWR trains will consist of DMU vehicles. As noted in Chapter 2. Alternatives Considered, Phase from Denver Union Station (DUS) to the South Westminster/7 st Avenue Station would be implemented with Electric Multiple Unit (EMU) technology. However, to obtain the most conservative results, modeling for this project was completed assuming DMU technology. To model the potential impact, the FRA has directed FTA to use train horns generating a sound level of 96 dba at feet. impact was assessed for both the FasTracks-only scenario and the all-stations scenario for opening day (25) and design year (235) operations as summarized below. Results No Action Alternative The No Action Alternative assumes that existing and committed improvements, as defined in Chapter 2., Alternatives Considered, would be implemented by others as planned May 2

10 Final Environmental Evaluation Direct, Indirect, Temporary Construction, and Cumulative Impacts It is anticipated that the roadway and transit projects included in the No Action Alternative would likely result in direct, indirect, temporary construction, and cumulative noise impacts. The location and severity of noise impacts resulting from these projects will be evaluated in the environmental documents being prepared for these projects. Preferred Alternative Direct Impacts NWR Corridor Alignment and Stations Tables and summarize the potential noise impacts for 25 operations at residential and institutional land uses along the NWR Corridor without mitigation for the FasTracks-only scenario and for the all-stations scenario, respectively. Corresponding results for year 235 operations are provided in Tables and In these tables, noise impacts are categorized as either severe or moderate based on the FTA criteria. To assist in the evaluation of mitigation, the moderate category is further divided into impacts that fall in the upper and lower 5 percent of the moderate impact range. Graphics of the locations where noise impacts are projected for each case are shown in figures included in the and Vibration Technical Memorandum for the NWR Corridor Project (HMMH 2). The results indicate that the total number of residential noise impacts without mitigation ranges from,89 for the FasTracks-only scenario in 25 to 2,346 for the all-stations scenario in 235; noise impact is also projected at 2 institutional sites. In the 235 allstation scenario, severe noise impacts are projected at 828 residences, one museum, one rehabilitation hospital, two schools, one park, and four day care facilities. Moderate noise impacts are projected at,58 residences, one hotel, and two schools. In terms of year of operation, greater noise impact is projected in 235 than in 25 due to the higher train volumes in 235. With regard to station scenario, greater noise impact is projected for the all-stations scenario than for the FasTracks-only scenario due to the effects of DMU speed and throttle profile effects near the additional stations. The results of the noise impact assessment for each section are summarized below. May

11 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR FASTRACKS-ONLY SCENARIO WITHOUT MITIGATION (25) Receptor Location Denver Section (Phase ) 5 Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Existing Level Predicted 2 Moderate Severe Impact Criteria Total Moderate Severe Level Level Increase DUS to West 64 th Avenue Denver Section Total Adams Section (Phase ) 5 W 64 th Avenue to Bradburn Boulevard Bowles House Museum Adams Section 5 Bradburn Boulevard to W 78 th Avenue Arapahoe House (Rehabilitation Hospital) Harris Park Elementary School W 78 th Avenue to Sheridan Boulevard Lower 5% Adams Section Total 35 Upper 5% 89 + Museum Westminster Section Sheridan Boulevard to Pierce Street Pierce Street to Wadsworth Boulevard Wadsworth Boulevard to Church Ranch Boulevard Broomfield Section 23 + Hospital + School Westminster Section Total th Avenue to SH SH 2 to Flatiron Circle Broomfield Section Total May 2

12 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR FASTRACKS-ONLY SCENARIO WITHOUT MITIGATION (25) Louisville Section Receptor Location Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Existing Level Predicted 2 Moderate Severe Impact Criteria Total Moderate Severe Level Level Increase Dillon Road to Empire Road Empire Road to South Boulder Road Park Louisville Middle School South Boulder Road to Baseline Road Bright Horizons Family Solutions La Petite Academy Louisville Section Total Boulder Section Baseline Road to 75 th Street th Street to 55 th Street Naropa University th Street to Pearl Street Marriott Courtyard hotel Pearl Street to Independence Road UCAR Child Care Center Family Learning Center Independence Road to 63 rd Street Boulder Section Total Lower 5% School 56 + Hotel Upper 5% Park + 2 Day Care 7 + School + 2 Day Care May

13 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR FASTRACKS-ONLY SCENARIO WITHOUT MITIGATION (25) Longmont Section Receptor Location Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Existing Level Predicted 2 Moderate Severe Impact Criteria Total Moderate Severe Level Level Increase Mineral Road to N. 83 rd Street N. 83 rd Street to N. 95 th Street N. 95 th Street to Main Street Front Range Community College Lower 5% Longmont Section Total: 56 TOTAL NOISE IMPACT: School + Hotel Upper 5% School Museum + School Hospital +2 Schools + Park + 4 Day Care Source: NWR Corridor Project Team, 29. Notes: levels are based on Ldn and measured in dba. 2 Predicted levels include horn and bell noise, where applicable (rounded to the nearest decibel). 3 All impacts represent residential units unless otherwise noted. 4 levels for land use category 3 are based on Leq and measured in dba. 5 Impacts associated with the Denver Section and a portion of the Adams Section (up to approximately Bradburn Boulevard) are included in Phase. Additionally, impacts associated with the South Westminster/7 st Avenue Station are included in Phase. mph = miles per hour May 2

14 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR ALL-STATIONS SCENARIO WITHOUT MITIGATION (25) Receptor Location Denver Section (Phase ) 5 Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Impact Criteria Existing Level Predicted 2 Moderate Severe Total Level Level Increase Moderate Lower 5% Upper 5% Severe DUS to West 64 th Avenue Denver Section Total Adams Section (Phase ) 5 W 64 th Avenue to Bradburn Boulevard Bowles House Museum Adams Section 5 Bradburn Boulevard to W 78 th Avenue Arapahoe House (Rehabilitation Hospital) Harris Park Elementary School W 78 th Avenue to Sheridan Boulevard Adams Section Total 37 + Museum + Hospital + School Westminster Section Sheridan Boulevard to Pierce Street Pierce Street to Wadsworth Boulevard Wadsworth Boulevard to Church Ranch Boulevard Westminster Section Total Broomfield Section 2 th Avenue to SH SH 2 to Flatiron Circle Broomfield Section Total Louisville Section Dillon Road to Empire Road Empire Road to South Boulder Road Park Louisville Middle School South Boulder Road to Baseline Road Bright Horizons Family Solutions La Petite Academy May

15 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR ALL-STATIONS SCENARIO WITHOUT MITIGATION (25) Receptor Location Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Impact Criteria Existing Level Predicted 2 Moderate Severe Louisville Section Total Total Level Level Increase Moderate Lower 5% Upper 5% Severe Park School + 2 Day Care Boulder Section Baseline Road to 75 th Street th Street to 55 th Street Naropa University th Street to Pearl Street Marriott Courtyard hotel Pearl Street to Independence Road UCAR Child Care Center Family Learning Center Independence Road to 63 rd Street Boulder Section Total Hotel Longmont Section Mineral Road to N. 83 rd Street N. 83 rd Street to N. 95 th Street N. 95 th Street to Main Street Front Range Community College Longmont Section Total: 53 TOTAL NOISE IMPACT:,35 + School + Hotel May School Museum + School School + 2 Day Care Hospital +2 Schools + Park + 4 Day Care Source: NWR Corridor Project Team, 29. Notes: levels are based on Ldn and measured in dba. 2 Predicted levels include horn and bell noise, where applicable (rounded to the nearest decibel). 3 All impacts represent residential units unless otherwise noted. 4 levels for land use category 3 are based on Leq and measured in dba. 5 Impacts associated with the Denver Section and a portion of the Adams Section (up to approximately Bradburn Boulevard) are included in Phase. Additionally, impacts associated with the South Westminster/7 st Avenue Station are included in Phase.

16 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR FASTRACKS-ONLY SCENARIO WITHOUT MITIGATION (235) Receptor Location Denver Section (Phase ) 5 Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Existing Impact Criteria Level Predicted 2 Moderate Severe Total Level Level Increase Lower 5% Moderate Upper 5% Severe DUS to W. 64 th Avenue Adams Section (Phase ) 5 W. 64 th Avenue to Bradburn Boulevard Bowles House Museum Adams Section 5 Bradburn Boulevard to W 78 th Avenue Arapahoe House (Rehabilitation Hospital) Harris Park Elementary School Denver Section Total W. 78 th Avenue to Sheridan Boulevard Adams Section Total Museum + Hospital + School Westminster Section Sheridan Boulevard to Pierce Street Pierce Street to Wadsworth Boulevard Wadsworth Boulevard to Church Ranch Boulevard Church Ranch Boulevard to 2 th Avenue Broomfield Section Westminster Section Total th Avenue to SH SH 2 to Flatiron Circle Broomfield Section Total May

17 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR FASTRACKS-ONLY SCENARIO WITHOUT MITIGATION (235) Louisville Section Receptor Location Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Existing Impact Criteria Level Predicted 2 Moderate Severe Total Level Level Increase Lower 5% Moderate Upper 5% Severe Dillon Road to Empire Road Empire Road to South Boulder Road Park Louisville Middle School South Boulder Road to Baseline Road Bright Horizons Family Solutions La Petite Academy Louisville Section Total 6 Boulder Section Baseline Road to 75 th Street th Street to 55 th Street Naropa University th Street to Pearl Street Marriott Courtyard hotel Pearl Street to Independence Road UCAR Child Care Center Family Learning Center Independence Road to 63 rd Street Boulder Section Total Hotel School Park + 2 Day Care School + 2 Day Care May 2

18 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR FASTRACKS-ONLY SCENARIO WITHOUT MITIGATION (235) Receptor Location Longmont Section Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Existing Impact Criteria Level Predicted 2 Moderate Severe Total Level Level Increase Lower 5% Moderate Upper 5% Severe Mineral Road to N. 83 rd Street N. 83 rd Street to N. 95 th Street N. 95 th Street to Main Street Front Range Community College Longmont Section Total: 56 TOTAL NOISE IMPACT:,67 + Hotel School Schools Museum + Hospital +2 Schools + Park + 4 Day Care Source: NWR Corridor Project Team, 29. Notes: levels are based on Ldn and measured in dba. 2 Predicted levels include horn and bell noise, where applicable (rounded to the nearest decibel). 3 All impacts represent residential units unless otherwise noted. 4 levels for land use category 3 are based on Leq and measured in dba. 5 Impacts associated with the Denver Section and a portion of the Adams Section (up to approximately Bradburn Boulevard) are included in Phase. Additionally, impacts associated with the South Westminster/7 st Avenue Station are included in Phase. May

19 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR ALL-STATIONS SCENARIO WITHOUT MITIGATION (235) Receptor Location Denver Section (Phase ) 5 Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Existing Level Predicted 2 Moderate Severe Impact Criteria Moderate Severe Total Level Level Increase DUS to W 64 th Avenue Denver Section Total Adams Section (Phase ) 5 W 64 th Avenue to Bradburn Boulevard Bowles House Museum Adams Section 5 Bradburn Boulevard to W 78 th Avenue Arapahoe House (Rehabilitation Hospital) Harris Park Elementary School W 78 th Avenue to Sheridan Boulevard Adams Section Total Museum + Hospital + School Westminster Section Sheridan Boulevard to Pierce Street Pierce Street to Wadsworth Boulevard Wadsworth Boulevard to Church Ranch Boulevard Church Ranch Boulevard to 2 th Avenue Westminster Section Total Broomfield Section 2 th Avenue to SH SH 2 to Flatiron Circle Broomfield Section Total Lower 5% Upper 5% May 2

20 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR ALL-STATIONS SCENARIO WITHOUT MITIGATION (235) Receptor Location Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Existing Level Predicted 2 Moderate Severe Impact Criteria Moderate Severe Total Level Level Increase Louisville Section Dillon Road to Empire Road Empire Road to South Boulder Road Park Louisville Middle School South Boulder Road to Baseline Road Bright Horizons Family Solutions La Petite Academy Lower 5% Louisville Section Total Upper 5% School Park + 2 Day Care Boulder Section Baseline Road to 75 th Street th Street to 55 th Street Naropa University th Street to Pearl Street Marriott Courtyard hotel Pearl Street to Independence Road UCAR Child Care Center Family Learning Center Independence Road to 63 rd Street Boulder Section Total + Hotel 44 + School + 2 Day Care May

21 Final Environmental Evaluation TABLE SUMMARY OF NOISE IMPACT ASSESSMENT FOR THE NWR CORRIDOR ALL-STATIONS SCENARIO WITHOUT MITIGATION (235) Receptor Location Distance to Near Track (feet) Train Speed (mph) Project Level Number of Impacts 3 Existing Level Predicted 2 Moderate Severe Impact Criteria Moderate Severe Total Level Level Increase Longmont Section Mineral Road to N. 83 rd Street N. 83 rd Street to N. 95 th Street N. 95 th Street to Main Street Front Range Community College Lower 5% Longmont Section Total: 53 TOTAL NOISE IMPACT:,3 + Hotel Upper 5% School Schools Museum + Hospital +2 Schools + Park + 4 Day Care Source: NWR Corridor Project Team, 29. Notes: levels are based on Ldn and measured in dba. 2 Predicted levels include horn and bell noise, where applicable (rounded to the nearest decibel). 3 All impacts represent residential units unless otherwise noted. 4 levels for land use category 3 are based on Leq and measured in dba. 5 Impacts associated with the Denver Section and a portion of the Adams Section (up to approximately Bradburn Boulevard) are included in Phase. Additionally, impacts associated with the South Westminster/7 st Avenue Station are included in Phase May 2

22 Final Environmental Evaluation Denver Section The Denver Section is discussed under Phase, later in this section. Adams Section The portion of the Adams Section from DUS to the South Westminster/7 st Avenue Station (approximately Bradburn Boulevard) is discussed under Phase, later in this section. The results of the remainder of the Adams Section, from Bradburn Boulevard north, indicate that the total number of residential noise impacts without mitigation (moderate and severe) in this section ranges from 543 for the FasTracks-only scenario in 25 to 88 for the all-stations scenario in 235. impacts are also projected at two institutional sites, including the Arapahoe House rehabilitation hospital and the Harris Park Elementary School. Westminster Section The results indicate that the total number of residential noise impacts (moderate and severe) without mitigation in this section ranges from 487 for the FasTracks-only scenario in 25 to 635 for the all-stations scenario in 235. Broomfield Section The results indicate that the total number of residential noise impacts without mitigation in this section ranges from 74 for the FasTracks-only scenario in 25 to 9 for the all-stations scenario in 235. Louisville Section The results indicate that the total number of residential noise impacts (moderate and severe) without mitigation in this section ranges from 22 for the FasTracks-only scenario in 25 to 266 for the all-stations scenario in 235. impacts are also projected at three institutional sites, including one park, two day care facilities (Bright Horizons Family Solutions and Le Petite Academy), and the Louisville Middle School. Boulder Section The results indicate that the total number of residential noise impacts (moderate and severe) without mitigation in this section ranges from 336 for the FasTracks-only scenario in 25 to 348 for the all-stations scenario in 235. impacts are also projected at three institutional sites, including one school (Naropa University), two day care facilities (UCAR Child Care Center and Family Learning Center), and at the Marriott Courtyard hotel. Longmont Section The results indicate that the total number of residential noise impacts (moderate and severe) without mitigation in this section ranges from 77 for the FasTracks-only scenario in 25 to 79 for the all-stations scenario in both 25 and 235. impacts are also projected at Front Range Community College. Phase Table below summarizes the potential noise impacts associated with implementation of Phase. Phase includes the Denver Section and a portion of the Adams Section extending up to the South Westminster/7 st Avenue Station (approximately Bradburn Boulevard). The impacts summarized below were modeled based on DMU technology. However, as previously stated if phased, Phase would be implemented with EMU technology, consistent with the Eagle P3 project corridors. Typically, EMU technology results in slightly fewer noise impacts as compared to DMU; therefore, the impacts presented May

23 Final Environmental Evaluation here are conservative. No direct noise impacts are projected in the Denver Section under the Preferred Alternative for either 25 or 235 conditions. All potential Phase noise impacts are located within the Phase portion of the Adams Section. TABLE SUMMARY OF PHASE NOISE IMPACTS (WITHOUT MITIGATION) Severe Phase (Denver Union Station to South Westminster/7 st Avenue Station) Residential Institutional Total Phase Severe Moderate Residential 45 7 (Lower 5%) Institutional Moderate Residential (Upper 5%) Institutional Total Phase Moderate Source: NWR Corridor Project Team, 29. Notes: Ranges exist due to potential differences in the 235 train schedules. Indirect Impacts No indirect noise impacts are projected for the Preferred Alternative. Temporary Construction Impacts Temporary noise impacts under the Preferred Alternative could result from construction activities. would result from utility relocation, grading, excavation, paving, installation of structures, and track work. Such impacts may occur in residential areas and at other noise-sensitive land uses located within several hundred feet of the alignment. The potential for noise impact would be greatest at locations near pile-driving operations for bridges and other structures and at locations close to any nighttime construction activities. Cumulative Impacts There would be no cumulative noise impacts for the Preferred Alternative Mitigation Measures According to FTA guidelines, when implementing noise impact criteria, severe impacts would be mitigated if at all practical. For mitigation at the moderate impact level, more discretion should be used and other project-specific factors should be included. Consistent with the FTA guidance, RTD is committed to mitigating all severe impacts wherever possible and to evaluating reasonable mitigation measures for moderate noise impacts. Mitigation measures for construction and operational noise impacts are summarized in Table To mitigate noise impact from train operations, noise control can be considered at the source, along the sound path and at the receiver. Source noise control options include limiting the use of train horns (e.g. by establishing Quiet Zones or using wayside horns to limit horn noise at grade crossings) and using special hardware at turnout locations May 2

24 Final Environmental Evaluation (e.g., by using spring-rail or moveable-point frogs in place of standard rigid frogs) if the turnouts cannot be relocated away from sensitive areas. barrier construction is the most common path noise control treatment and noise control can be applied at the receiver by using sound insulation treatments at residences and institutional buildings. The results of the noise analysis suggest that the most effective mitigation approach is to establish Quiet Zones to eliminate train horn noise at all at-grade crossings near affected noise-sensitive areas. As stated in the RTD Board policy, The Responsible Rail Amendment, RTD is committed to assisting local jurisdictions in their Quiet Zone application process. RTD is making progress toward implementing Quiet Zones for the NWR Corridor. However, should they not be implemented, the secondary plan is to install wayside horns. In either case, additional treatments (e.g. noise barriers and sound insulation) would be applied if practical to mitigate residual impacts. TABLE PROPOSED MITIGATION MEASURES NOISE Impact Impact Type Mitigation Measures Construction Operations Source: NWR Corridor Project Team, 29. Minimize nighttime construction in residential neighborhoods. Locate stationary construction equipment as far as possible from noisesensitive sites. Construct noise barriers, such as temporary walls or piles of excavated material, between noisy activities and noise-sensitive receivers. Re-route construction-related truck traffic along roadways that will cause the least disturbance to residents. Quiet Zones will be implemented prior to operations at all but 7 grade crossings from W. 64 th Avenue in Adams County to SH 9 in Longmont. RTD will assist the local jurisdictions with their applications to the railroads and the FRA. Applications for Quiet Zones must be submitted by the local jurisdictions. Should Quiet Zones not be implemented prior to operations, alternate methods of noise mitigation, such as wayside horns and sound insulation, will be used. Install 3,2 lineal feet of -foot high noise barriers. At locations where there are noise impacts that cannot be mitigated with Quiet Zones, the construction of noise barriers has been investigated to mitigate residual severe noise impacts or to mitigate residual moderate noise impacts where reasonable. RTD will consider the use of noise barriers to mitigate moderate noise impacts reasonable if () the noise impact is within the top 5 percent of the moderate impact range (see Figure 3.8-2), (2) the cost range for the noise barrier is within $3,562 to $53,483 (in 28 dollars) per benefited residence, and (3) the minimum number of affected parcels is at least or the length of a noise barrier is at least 8 feet. Based on the above guidelines, the noise barrier recommendations for the NWR Corridor are summarized in Table The results apply to 235 operations for both station scenarios and indicate that a total of 3,2 lineal feet of -foot high noise barriers would be required to supplement the Quiet Zones. The noise barrier analysis assumes that Quiet Zones would be May

25 Final Environmental Evaluation implemented at all grade crossings from W. 64 th Avenue in Adams County to SH 9 in Longmont except at the following seven grade crossings 3 : 2 th Avenue in Broomfield Dillon Road in Louisville 55 th Street in Boulder 63 rd Street in Boulder N. 83 rd Street in Longmont Ogallala Road in Longmont Private Driveway in Longmont Individuals, neighborhoods, or businesses wishing to request a change to or elimination of a noise barrier must follow RTD s Barrier Change Policy, which states that 75 percent of the affected property owners must submit proof in writing to RTD stating their approval of the reduction in mitigation, reasons for desiring the elimination of mitigation, that they will hold RTD harmless for this change, and that they will be responsible for informing potential buyers of their property or their agents that noise mitigation was offered and refused, or was reduced, to meet the desires of the affected parties. The affected parties are responsible for collecting the above information and submitting it in a single, notarized package to RTD. TABLE SUMMARY OF RECOMMENDED NOISE BARRIER MITIGATION FOR THE NWR PREFERRED ALTERNATIVE Alignment Section Location Side of Track Height 2 (feet) Length (feet) Adams W. 74th Avenue to W. 75th Avenue Southbound 5 Louisville Longmont South Boulder Road to Sunnyside Street Ken Pratt Boulevard to Boston Avenue Southbound,2 Southbound,5 TOTAL 3,2 Source: NWR Corridor Project Team, 29. Notes: All noise barriers are assumed to be located 5-2 feet from the near track within railroad right-of-way. 2 barrier heights are assumed to be above track grade. Summaries of noise impact mitigation effectiveness for 235 operations are provided in Table 3.8- for the FasTracks-only scenario and in Table 3.8- for the all-stations scenario. These tables compare the projected numbers of moderate and severe noise impacts () with no mitigation, (2) with Quiet Zones, and (3) with both Quiet Zones and noise barriers. The results project that the implementation of Quiet Zones alone would be sufficient to eliminate all severe noise impacts. With a combination of the recommended Quiet Zone and noise barrier mitigation measures, moderate impacts in 235 would remain at 89 residences for the FasTracks-only scenario and at 235 residences for the all-stations 3 Quiet Zones proposed at Mineral Road in Boulder, Independence Road in Boulder, and S. Sunset Street in Longmont are included based on FRA safety requirements May 2

26 Final Environmental Evaluation scenario. In addition, there would be residual moderate noise impacts at four institutional sites in the Boulder Section including one hotel (the Marriott Courtyard hotel), one school (Naropa University), and two day care facilities (the UCAR Child Care Center and the Family Learning Center). If Quiet Zones are not implemented, wayside horns would significantly reduce the noise impacts along the NWR Corridor. However, they would be much less effective than Quiet Zones due to their impact at sensitive receptors near the grade crossings. With wayside horns, it is estimated that severe noise impacts would remain at residences and two institutional sites (Naropa University and the UCAR Child Care Center) in 235. May