Roadway/Structure Widening Project Lansdale Montgomery County, PA NOISE ANALYSIS REPORT Prepared for: Pennsylvania Turnpike Commission P.O. Box 67676 Harrisburg, PA 17106-7676 August 2006 FINAL
EXECUTIVE SUMMARY This document discusses the noise analysis that was performed along the Northeast Extension of the Pennsylvania Turnpike (I-476) between MP A30.30 (adjacent to the Lansdale Interchange) and MP A31.73 (Fretz Road overpass) in Lower Salford and Towamencin Townships, Montgomery County, Pennsylvania. The proposed construction would consist of widening the structures over Skippack Creek (NB-52) and Wambold Road (NB-150) as well as the roadway connecting the two structures. In addition, the Turnpike will be graded for future full-width widening from the southern construction limit (MP A30.30) to Fretz Road (MP A31.73). The existing conditions have been determined for the year 2005 and the proposed design year set at 2025, with two design options analyzed; 4-lanes of pavement and 6-lanes of pavement. The noise study has shown that noise mitigation consideration is warranted at 12 receptor locations representing 20 residences, for both the 4-Lane and 6-Lane design options. Since all feasible design options exceed reasonable cost criteria, no noise mitigation measures are recommended within the noise study area. Lansdale Noise Analysis Report i
TABLE OF CONTENTS Page EXECUTIVE SUMMARY... i TABLE OF CONTENTS... ii I. INTRODUCTION... 1 II. METHODOLOGY... 7 A. Analytical Procedures... 7 B. Evaluation Criteria... 9 C. Noise Abatement Measures... 9 III. EXISTING CONDITIONS... 11 A. Noise Sensitive Area 1... 12 B. Noise Sensitive Area 2... 12 C. Noise Sensitive Area 3... 12 D. Noise Sensitive Area 4... 12 E. Noise Sensitive Area 5... 12 F. Noise Sensitive Area 6... 13 G. Noise Sensitive Area 7... 13 IV. PREDICTED DESIGN YEAR NO-BUILD ALTERNATIVE NOISE LEVELS... 14 V. IMPACTS AND MITIGATION RECOMMENDATIONS FOR DESIGN YEAR 2025... 15 A. Noise Sensitive Area 1... 15 B. Noise Sensitive Area 2... 15 C. Noise Sensitive Area 3... 15 D. Noise Sensitive Area 4... 23 E. Noise Sensitive Area 5... 26 F. Noise Sensitive Area 6... 27 G. Noise Sensitive Area 7... 27 VI. CONSTRUCTION NOISE CONSIDERATIONS AND MITIGATION... 39 VII. PUBLIC INVOLVEMENT... 40 VIII. SUMMARY AND RECOMMENDATIONS... 41 REFERENCES... 42 LIST OF PREPARERS... 43 Lansdale Noise Analysis Report ii
TABLES Table 1: Hourly Weighted Sound Levels (db(a)) for Various Land Use Activity Categories... 7 Table 2: Noise Levels in db(a)... 11 Table 3A: 4-Lane Option, Maximized Design... 31 Table 3B: 4-Lane Option, Line-Of-Sight Design... 32 Table 3C: 4-Lane Option, Optimized Design... 33 Table 4A: 6-Lane Option, Maximized Design... 34 Table 4B: 6-Lane Option, Line-Of-Sight Design... 35 Table 4C: 6-Lane Option, Optimized Design... 36 Table 5: Feasibleness and Reasonableness of Proposed s for 4-Lane Option Design Year (2025)... 37 Table 6: Feasibleness and Reasonableness of Proposed s for 6-Lane Option Design Year (2025)... 38 FIGURES Figure 1... 2 PLATES Plate Index... 3 Plate 1A... 4 Plate 1B... 5 Plate 1C... 6 Plate 2A... 16 Plate 2B... 17 Plate 2C... 18 Plate 3A... 19 Plate 3B... 20 Plate 4A... 21 Plate 4B... 22 APPENDICES APPENDIX A: Pennsylvania Turnpike Traffic Volumes APPENDIX B: Field Monitoring Data Sheets APPENDIX C: TNM Data APPENDIX D: Warranted, Feasible and Reasonableness Worksheets APPENDIX E: Field Data Sheet APPENDIX F: Calibration Sheets Lansdale Noise Analysis Report iii
I. INTRODUCTION The Lansdale Project is located along the Northeast Extension in Lower Salford and Towamencin Townships, Montgomery County, Pennsylvania, and extends between Milepost A30.30 and Milepost A31.73 of the northeast extension of the Pennsylvania Turnpike (Figure 1). The project is the proposed widening of the Pennsylvania Turnpike (I-476) structures over Skippack Creek (NB-52) and Wambold Road (NB-150), including the roadway connecting the two structures. In addition, the Turnpike will be graded for future full-width widening from the southern construction limit (MP A30.30) located at the south end near the Lansdale Interchange to Fretz Road (MP A31.73) located north of Wambold Road. The majority of the study area encompasses agricultural lands with a few residential lots and commercial property mixed throughout. The improvement to this north-south highway is needed to support the continued attraction and retention of businesses and employment opportunities in the region. Efficient and reliable highway capacity is necessary to accommodate passenger and freight travel, moving people, goods, and services throughout the region. Improvements to the mainline include widening of the structures and lanes in both the north and southbound lanes to accommodate current and predicted future traffic volumes. This document discusses the noise analysis that has been performed to identify the existing and proposed highway traffic noise conditions for the Lansdale Project (Plates Index and 1A-1C). Noise monitoring and modeling, impact evaluation, and mitigation feasibility and reasonableness will be discussed for design year 2025 after widening of the mainline travel lanes for the 4-lane option and 6-lane option. Highway noise impact assessment procedures, noise abatement criteria and all documentation are in accordance with Pennsylvania Department of Transportation (PennDOT) revised Publication #24, Project Level Highway Traffic Noise Handbook, February 2, 2002. PennDOT guidelines are based on the updated Federal Highway Administration (FHWA) Federal Aid Policy Guide 23 CFR 772, U.S. Government Printing Office, updated December 9, 1991. Lansdale Noise Analysis Report 1
SOUDERTON PENNSYLVANIA BUCKS PROJECT LOCATION COUNTY MONTGOM COUNTY Montgomery County FRANCONIA HATFIELD FRETZ RO A D Project Location LOWER SALFORD TOWAMENCIN LANSDALE PACK UPPER GWYNEDD NORTH WA WORCESTER REGIONAL LOCATION MAP Roadway/Structure Widening MP A30.30 to A31.73 Montgomery County, PA Display Scale 1" = 1 Mile Figure 1 Sources : Pennsylvania Department of Transportation, Bureau of Planning and Research, State Maintained Roadways and Boundary Files.
II. METHODOLOGY A. Analytical Procedures Traffic noise impact analysis and abatement measures were evaluated in accordance with the methodologies and procedures set forth by the Federal Highway Administration (FHWA) and the Pennsylvania Department of Transportation (PennDOT) in Publication #24, Project Level Highway Traffic Noise Handbook, dated February 2, 2002. The first step in highway traffic noise analysis is to assess the existing acoustical environment. Noise monitoring of existing conditions is the primary means of establishing background noise levels and propagation characteristics throughout the project area. The initial phase of the monitoring process is the selection of noise sensitive receptors. Sensitive receptors are defined as those land uses that are especially susceptible to noise impacts. These may include hospitals, schools, residences, motels, hotels, recreational areas, parks, and places of worship. For this portion of the Lansdale Project, the sensitive receptors identified within the study area are all considered Activity Category B, as defined by the FHWA traffic noise abatement criteria (NAC) (23 CFR Part 772) which are summarized in Table 1. Table 1 provides a brief description as well as the recommended federal and state noise criteria for each of the different activity categories. Table 1 Hourly Weighted Sound Levels (db(a)) for Various Land Use Activity Categories Land Use Activity Category Exterior Leq(h) Description of Land Use Activity Category A 57 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. B 67 Residences, schools, churches, parks, picnic areas, recreation areas, playgrounds, active sports areas, motels, hotels, libraries and hospitals. C 72 Developed lands, properties, or activities not included in Categories A or B above. D -- Undeveloped lands. 52 E Interior Source: Title 23 CFR, Part 772 Residences, motels, hotels, public meeting rooms, schools, churches, libraries, hospitals, and auditoriums. After selection of noise sensitive receptors, monitoring of the existing acoustical environment was conducted. All monitoring for this project was performed using a Casella CEL-360 noise dosimeter. Calibration of the meter was performed using a Casella CEL 110/2 calibrator. Lansdale Noise Analysis Report 7
The data collected in the monitoring process was used to calculate the existing hourly equivalent noise level, Leq(h), for each noise sensitive receptor. In accordance with Section II-7 of PennDOT Publication #24, data was recorded on a per minute basis, for a 15-minute duration at sites M1 and M2, and for a 24-hour duration at Site M3. This was done in order to ensure that the Leq(h) levels established were a true representation of noise conditions along this segment. To calculate the Leq(h) for each monitoring period, the Leqs for each of the one-minute intervals are logarithmically averaged for each sensitive receptor. Additional data collected during the monitoring process include atmospheric conditions, major noise sources, background noise sources and unusual noise events. Traffic is grouped into one of three categories for this project: cars, medium trucks and heavy trucks. Medium trucks are defined as trucks having two axles. Heavy trucks are vehicles having three or more axles. Cars are all remaining vehicles. Appendix A provides the existing 2005 and design year 2025 traffic volumes, speeds, and composition. Upon completion of noise monitoring, a computer model of the existing roadway network and monitored receptors was constructed using data from digital topographic and contour maps, highway design files, and traffic volumes provided by the PTC and Pennoni Associates, Inc. The data files for each computer noise model may be found in Appendix C. Modeling of the project area was accomplished by applying the FHWA Traffic Noise Model (TNM) computer model, Version 2.5, which has been established as a reliable tool for representing noise generated by highway traffic. To represent the actual conditions, a numerical coordinate system of the roadway network and receivers was used. The TNM computer model uses a three-dimensional Cartesian coordinate (x, y and z) system to represent the roadways, terrain features and receivers in the study area. Noise levels are then predicted for various scenarios of traffic flow, geometrics and topography. In addition to the definition of physical features within the coordinate geometry system, the model includes two other categories of input variables. Traffic volumes and posted speeds were entered for each of the three vehicle types. The modeling process continued with model verification, in accordance with PennDOT procedures. This was performed by comparing the monitored traffic noise levels with noise levels generated by the computer model, using the traffic volumes and speeds that were provided by the PTC. This comparison ensures that reported changes in noise levels between future and existing conditions are due to changes in conditions and do not erroneously reflect discrepancies between the modeling and monitoring techniques. This process is also referred to as model calibration, since the source-path-receiver relationships may be adjusted to better represent the observed propagation characteristics. A difference between the monitored and modeled levels of three (3) A-weighted decibels or less is considered acceptable, since this is the minimum level of change detectable by the typical human ear, and is the acceptable level of difference recommended by PennDOT s Publication #24. The monitored noise level data may be found in Appendix B, and the field data sheet is located in Appendix E. Following calibration of the existing conditions models, additional modeling sites were added to thoroughly predict existing noise levels throughout the project area. This additional noise Lansdale Noise Analysis Report 8
modeling was performed for existing conditions using worst-case traffic data supplied by the PTC. This step was performed to further evaluate existing worst-case noise conditions associated with worst-case traffic volumes and composition, and to determine the noise abatement criteria (NAC) at modeling sites where no field measurements are available. The next step in the noise analysis was to project design year noise levels, and determine if the future levels will approach or exceed state and/or federal NAC. If the criteria was approached or exceeded at any receptor (or residences represented by that receptor), the abatement considerations are warranted to reduce noise to acceptable levels. Models for the future Build and future No-Build scenarios were created for purposes of future noise level impact assessment. The future Build model was created by adding the proposed roadway design into the existing conditions model. Projected design year (2025) traffic volumes, speeds, and compositions have been assigned to all roadways, and future noise levels are predicted. For the future No-Build model design year (2025) traffic volumes, speeds, and compositions are assigned to the unchanged existing condition roadway network. B. Evaluation Criteria The CEL-360 dosimeter and Casella 110/2 calibrator meet all requirements of the American National Standard Specification for Sound Level Meters, ANSI S1.4 1983 Type S2. Monitoring was conducted in accordance with the U.S. Department of Transportation, FHWA report titled A Measurement of Highway-Related Noise, FHWA Report No. FHWA-PD-96-046, May 1996. The FHWA Traffic Noise Model (TNM) Version 2.5 is described in the U.S. Department of Transportation, Federal Highway Administration s FHWA Traffic Noise Model User s Guide, FHWA-PD-96-009, January 1998. Highway noise impact assessment procedures, noise abatement criteria and all documentation are in accordance with Pennsylvania Department of Transportation (PennDOT) revised Publication #24, Project Level Highway Traffic Noise Handbook, February 2, 2002. PennDOT guidelines are based on the updated Federal Highway Administration (FHWA) Federal Aid Policy Guide 23 CFR 772, U.S. Government Printing Office, updated December 9, 1991. C. Noise Abatement Measures After future noise levels were predicted, mitigation analysis was performed. The three steps of mitigation analysis included determination of: 1.) noise abatement consideration is warranted using the Warranted, Feasible and Reasonable Worksheets in Appendix D, 2.) if noise abatement is feasible, and 3.) if noise abatement is reasonable. Abatement consideration is warranted where future noise levels have been predicted to exceed NAC. The federal procedures require the state to specify the level which approaches the criteria. For Activity Category B, PennDOT considers a level of 66 db(a) up to 67 db(a) as approaching the federal criteria of 67 db(a). Additionally, the federal procedures stipulate that abatement consideration is required if the project results in a substantial noise increase above existing condition. PennDOT interprets FHWA guidelines for substantial noise increase as an increase of 10 db or more above existing noise levels. Pennsylvania guidelines state that if a noise level at any given receptor approaches or exceeds the appropriate abatement criterion, or if predicted traffic noise levels substantially Lansdale Noise Analysis Report 9
exceed the existing noise levels, abatement considerations are required. While the TNM analysis and the CEL Soundtrack db12 v.2.5 calculate sound levels to the tenth of a db(a), per PennDOT s Publication #24 Section II-12, all reported sound levels are rounded to the nearest whole db(a). After identifying areas where abatement consideration was warranted, the feasibility of potential mitigation was then analyzed. In determining feasibility of noise abatement, PennDOT guidelines require that a noise reduction, also known as insertion loss, of at least 5 db be achieved at the majority of impacted residences. If proposed mitigation scenarios (typically vertical concrete barriers or earth berms) can satisfy this requirement, and the mitigation can be engineered without prohibiting required vehicular or pedestrian access, or create safety issues, the mitigation is considered feasible. Due to constraints on available construction space, earthen berms were not considered to be a feasible option since they would require acquisition of additional right-of-way along the limits of the project area. For this study, four potential vertical concrete noise barriers were considered. Some segments of the barriers would be mounted on a structure. The maximum height of a barrier on a structure allowed by the PTC is 14.0 feet. For each barrier, three design scenarios were considered for each proposed barrier s location. Design Option 1, Maximum Height, consisted of setting the height of each segment along the length of the proposed barrier at the 20.0-foot maximum allowed by the PTC for barriers which are not mounted on a structure, and a 14.0-foot maximum for segments on structures. Design Option 2, Line of Sight, consisted of setting the height of each barrier segment at the maximum height necessary to interrupt the line of sight between the receiver and the noise source, which is traffic in this case. Design Option 3, Optimized Height, consisted of setting each barrier segment height at the minimum height required to achieve a predicted noise level equal to or less than 66 db(a), while achieving an insertion loss of at least 5 db, then adjusting each segment height in order to maximize insertion losses without exceeding reasonableness cost criteria. If mitigation is determined to be feasible, the reasonableness of the mitigation is analyzed. This determination takes into account the cost effectiveness of the mitigation. In addition to consideration of impacted residences receiving feasible mitigation, non-impacted residences that receive benefit from the mitigation can also be considered when determining cost effectiveness. PennDOT s noise policy considers any impacted residence receiving at least 3 db and nonimpacted residence receiving a 5 db or greater insertion loss as receiving benefit from the proposed barrier. If the abatement cost is less than $50,000.00 per benefited residence, it is considered reasonable (pending public input). It should be noted that the $50,000.00 per benefited residence adopted by PennDOT is the maximum dollar amount allowed by FHWA. Public involvement for this project will be implemented in accordance with the procedures established in the Pennsylvania Department of Transportation (PennDOT) revised Publication #24, Project level Highway Traffic Noise Handbook, February 2, 2002 Step 7, Section II-23 thru II-26. Lansdale Noise Analysis Report 10
III. EXISTING CONDITIONS Monitoring was conducted at three locations in the study area. On July 20, 2005, at Sites M1 and M2 15-minute peak and off-peak measurements were taken. On August 15, 2005 a measurement was taken during a 24-hour period at Site M3. In order to facilitate the analysis, noise sensitive receptors were grouped into Noise Sensitive Areas (NSAs) based on geographic proximity and topographical features. The discussion of existing conditions that follows, as well as the impact determination and mitigation section, will be discussed for each NSA. Table 2 summarizes the monitoring data for each NSA. Model verification results as well as all unmitigated noise levels calculated for the analysis are presented in Table 2. All noise monitoring and modeling receiver locations, as well as all NSA boundaries are located on Plates 1A-1C. NSA Receiver Name Existing Year (2005) Field Monitored Table 2 Noise Levels in db(a) Existing Year (2005) Modeled No-Build Design Year (2025) Build: 4-Lane (without ) Build: 6-Lane (without ) 1 M1 56 (55.5, peak) 57 (56.7) 61 (61.0) 61 (60.9) 60 (59.9) 2 R2 57 (57.0) 62 (61.5) 62 (62.3) 62 (62.3) 3 R100 68 (67.5) 72 (71.9) 72 (71.5) 71 (71.4) 4 M2 57 (57.3, peak) 56 (56.0) 61 (60.5) 62 (61.6) 62 (62.0) R3 71 (71.1) 75 (75.4) 73 (72.8) 74 (74.3) R102 59 (59.1) 64 (63.6) 63 (63.4) 63 (63.3) R103 62 (61.9) 66 (66.2) 65 (65.3) 65 (64.5) R104 62 (61.6) 66 (66.0) 64 (64.3) 65 (64.7) R105 55 (54.7) 59 (59.1) 58 (58.0) 59 (58.7) R109 60 (59.7) 64 (64.3) 66 (65.8) 66 (65.9) R110 69 (68.9) 73 (73.1) 72 (72.3) 74 (73.6) R112 64 (64.4) 69 (68.8) 68 (67.6) 67 (66.8) 5 ---- ---- ---- ---- ---- ---- 6 R200 75 (75.0) 79 (79.2) 78 (78.1) 78 (78.1) R201 67 (66.8) 71 (71.2) 71 (70.9) 71 (70.9) 7 M3 67 (66.8, 24-hr) 71 (70.9) 75 (75.2) 68 (68.3) 70 (69.7) R1 69 (68.6) 73 (73.1) 73 (72.6) 73 (72.5) R114 66 (66.1) 71 (70.8) 67 (67.0) 68 (67.6) R116 70 (70.1) 74 (74.4) 72 (72.1) 74 (73.5) R118 65 (64.7) 69 (69.1) 64 (64.3) 64 (64.3) R119 70 (70.3) 75 (74.6) 70 (70.2) 71 (70.7) Notes: * Shading indicates sound levels exceed NAC. ** While the TNM analysis and the CEL Soundtrack db12 v.2.5 calculate sound levels to the tenth of a db(a), per PennDOT s Publication #24 Section II-12, all reported sound levels are rounded to the nearest whole db(a). For clarification, unrounded sound levels have been provided in parenthesis. Lansdale Noise Analysis Report 11
The Lansdale Project s segment naming and stationing convention progresses from south to north. A. NSA 1 NSA 1 is located on the west side of the Turnpike and extends from the southern end of the project to Wambold Road. It begins at the Lansdale Interchange and traverses commercial property, woodlands, and a church property until it terminates at the southern side of Wambold Road. NSA 1 consists of approximately two residential land uses, including one church, represented by Site M1. Existing year (2005) modeled noise levels are predicted to be in the range of 57 db(a) within the limits of NSA 1. B. NSA 2 NSA 2 is located in the southern limits of the study area on the west side of the Turnpike. It begins on the north side of Wambold Road and traverses open farmland, residential property and forestland until it terminates at the Skippack Creek. NSA 2 consists of approximately four residential land uses, represented by Site R2. Existing year (2005) modeled noise levels are predicted to be in the range of 57 db(a) within the limits of NSA 2. C. NSA 3 NSA 3 is located in the southern limits of the study area on the west side of the Turnpike, between NSA 2 and the Turnpike. It begins on the northern edge of the Wambold Road and traverses residential property and farmland until it terminates at Skippack Creek. NSA 3 consists of approximately one residential land use, represented by Site R100. Existing year (2005) modeled noise levels are predicted to be in the range of 68 db(a) within the limits of NSA 3. D. NSA 4 NSA 4 is located in the northern limits of the study area on the west side of the Turnpike. It begins on the north side of Skippack Creek and traverses residential property until it terminates at Fretz Road, the northern limit of the project area. NSA 4 consists of approximately twentyfive residential land uses, represented by Sites M2, R3, R102, R103, R104, R105, R109, R110 and R112. Existing year (2005) modeled noise levels are predicated to range from 55 to 71 db(a) within the limits of NSA 4. E. NSA 5 NSA 5 is located in the northern limits of the study area on the wide side of the Turnpike. NSA 5 is on the west side of NSA 4, separated by Freed Road. No sensitive receptors have been studied in NSA 5 due to its distance from the Turnpike and also due to the existence of the secondary roadway passing between NSA 5 and the Turnpike. Lansdale Noise Analysis Report 12
F. NSA 6 NSA 6 is located in the southern limits of the study area on the east side of the Turnpike. It begins at the Lansdale Interchange and traverses commercial properties and farmland until it terminates at the south side of Wambold Road. NSA 6 consists of approximately two residential land uses, represented by Sites R200 and R201. Existing year (2005) modeled noise levels are predicted to be in the range from 67 to 75 db(a) within the limits of NSA 6. G. NSA 7 NSA 7 is located in the northern limits of the study area on the east side of the Turnpike. It beings on the north side of Wambold Road and traverses residential property, farmland and woodlands until it terminates at Fretz Road. NSA 7 consists of approximately eleven residential land uses, represented by Sites M3, R1, R114, R116, R118 and R119. Existing year (2005) modeled noise levels are predicted to range from 65 to 71 db(a) within the limits of NSA 7. Lansdale Noise Analysis Report 13
IV. PREDICTED DESIGN YEAR NO-BUILD ALTERNATIVE NOISE LEVELS Predicted noise levels for both the future (2025) No-Build and Future 4 and 6 lane (2025) Build conditions are presented in Table 2.. The design year 2025 No-Build condition experiences an increase in noise levels over existing (2005) conditions due to the increase in traffic volumes. The 4 and 6-lane Build conditions also experiences an increase over existing conditions, but the proposed 4 and 6-lane configurations results in sound levels slightly more or slightly less than those expected for the No-Build condition. In most of these cases the sound level differences are attributed to rounding of the sound levels to the nearest whole db(a) in accordance with PennDOT Publication 24, Section II-12. In the case of Receivers M3, R114 and R118 and R119, their topographic position relative to the roadway combined with the new travel land locations and the additional roadway grading have combined to lower the 4 and 6-lane Build (with no barrier) conditions noise levels to below the No-Build condition. For the future No-Build condition, design year (2025) traffic volumes, vehicle composition and speeds were assigned to all existing roadways without changes made to vertical or horizontal geometry. Appendix A provides the existing 2005 and proposed design year 2025 traffic volumes, speeds, and composition. The No-Build condition noise evaluation was performed for comparative purposes to the design year Build condition. Mitigation recommendations are not discussed for the No-Build condition. Lansdale Noise Analysis Report 14
V. IMPACTS AND MITIGATION RECOMMENDATIONS FOR DESIGN YEAR 2025 Impact determination for the Build scenario is discussed below for each NSA. A discussion of mitigation recommendations is given for each NSA immediately following the impact determination, if warranted for that particular NSA. Plates 2A-2C show the proposed design conditions for the 4-Lane Option. A 6-Lane conceptual widening option was also evaluated, which involved widening of the pavement to the outside of each direction of travel. No plates are available for the 6-Lane Option due to the lack of detailed roadway design. Plates 3A-3B show proposed barrier locations for the 4-Lane Option and Plates 4A-4B show the proposed barrier locations for the 6-Lane design condition. Tables 3a, 3b, and 3c summarize barrier feasibility per each NSA that warrants mitigation consideration and reasonableness of the barriers that provide feasible noise reductions in the 4-Lane design year condition. Tables 4a, 4b, and 4c summarize barrier feasibility per each NSA that warrants mitigation consideration and reasonableness of the barriers that provide feasible noise reductions in the 6-Lane design year condition. Tables 5 and 6 summarize the feasibleness and reasonableness of each barrier considered for the design year 2025. A. NSA 1 Design year Build noise levels were predicted to be 61 db(a) for the 4-Lane Option and 60 db(a) for the 6-Lane Option within the limits of NSA 1, at Site M1 representing approximately two dwelling units (DU) (Table 2). This is an increase from the existing sound level of 57 db(a). Since predicted noise levels are less than the 66 db(a) NAC approach criteria and the increase is not 10 db or greater over the existing sound level for Site M1 in this NSA, mitigation consideration is not warranted. B. NSA 2 Design year Build noise levels were predicted to be 62 db(a) for both the 4-Lane and the 6-Lane Options within the limits of NSA 2, at Site R2 representing four DUs (Table 2). This is an increase from the existing sound level of 57 db(a). Since predicted noise levels are less than the 66 db(a) NAC approach criteria and do not increase 10 db or greater over the existing sound level for this NSA, mitigation consideration is not warranted. C. NSA 3 Design year Build noise levels were predicted to be 72 db(a) for the 4-Lane Option and 71 db(a) for the 6-Lane Option within the limits of NSA 3, at Site R100 representing approximately one DU (Table 2). This is an increase from the existing sound level of 68 db(a). Since predicated noise levels are greater than the 66 db(a) NAC approach criteria for Sites R100 and in this NSA, mitigation consideration is warranted. Lansdale Noise Analysis Report 15
D. NSA 4 Design year Build noise levels were predicted to range from 58 to 73 db(a) for the 4-Lane Option and 59 to 74 db(a) for the 6-Lane Option within the limits of NSA 4, at Sites M2, R3, R102, R103, R104, R105, R109, R110, R112 representing approximately twenty-five DUs (Table 2). This is an increase from existing sound levels at all sites. Since predicated noise levels are greater than the 66 db(a) NAC approach criteria for Sites R3, R109, R110, and R112 in this NSA, mitigation consideration is warranted. Since R100 located in NSA 3 was within close proximity to Sites R3, R109, R110, and R112 in NSA 4 there was an overlap of the barriers within NSA 3 and 4. Therefore, one Maximum Height and one Line of Sight ( 1AB) were analyzed for both NSA 3 and 4 impacted receivers. An Optimized Height was also analyzed; however, the optimization broke the one long barrier into two smaller optimized barriers. 1A provides mitigation in NSA 3 for Site R100 and 1B provides mitigation in NSA 4 for Sites R3, R109, R110 and R112. Although Site M1 in NSA1 does not warrant noise mitigation, it was included in the 6-Lane Option barrier analysis to determine if it would benefit from the proposed 1AB. The benefit was found to be less than 1dB; therefore, Site M1 was not analyzed in the 4-Lane Option. 4-LANE OPTION Design Option 1: Maximum Height One maximum height barrier ( 1AB) was considered for Sites R100, R2, M2, R3, R102, R103, R104, R105, R109, R110, and R112 at a height of 20.00 feet from end to end with the exception of on-structure barriers which were at a maximum allowable height of 14.00 feet (see Table 3A for mitigated sound levels and impacted vs. benefited receivers). The predicted sound levels at the maximum wall height ranged from 54 to 62 db(a) for 1AB. The insertion loss per receiver, at maximum wall height was 9 db for R100 (1 DU), 7 db for R2 (4 DU), 6 db for M2 (11 DU), 11 db for R3 (1 DU), 8 db for R102 (2DU), 10 db for R103 (1 DU), 9 db for R104 (1DU), 4 db for R105 (2 DU), 8 db for R109 (3 DU), 10 db for R110 (2 DU), and 10 for R112 (2 DU). 1AB is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimal 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24 (majority is defined as 50% or more of the impacted receptor units). Design Option 2: Line of Sight One line of sight barrier ( 1AB) was considered for Sites R100, R2, M2, R3, R102, R103, R104, R105, R109, R110, and R112 at varying heights from end to end (see Table 3B for mitigated sound levels and impacted vs. benefited receivers). The predicted sound levels at the varying line of sight heights ranged from 57 to 68 db(a). The insertion loss per receiver, at the varying line of sight heights was 6 db for R100 (1 DU), 3 db for R2 (4 DU), 1 db for M2 (11 DU), 5 db for R3 (1 DU), 3 db for R102 (2 DU), 5 db for R103 (1 DU), 6 db for R104 (1 DU), 2 db for R105 (2 DU), 2 db for R109 (3 DU), 5 db for R110 (2 DU), and 7 db for R112 (2 DU). 1AB is not feasible since it does not reduce sound levels below the 66 db(a) NAC Lansdale Noise Analysis Report 23
approach criteria and achieve the minimal 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. Design Option 3: Optimized Height Two optimized height barriers were considered at varying heights from end to end (see Table 3C for mitigated sound levels and impacted vs. benefited receivers). 1A was considered for Sites R100, M2 and R2. The predicted sound levels at the varying optimized height was ranged from 60 to 65 db(a) for 1A (see Table 3C for mitigated sound levels and impacted vs. benefited receivers). The insertion loss per receiver at the varying optimized heights was 6 for R100 (1 DU), 1 for M2 (11 DU), and 3 for R2 (4 DU). 1A is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimal 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. 1B was considered for Sites R3, R102, R103, R104, R105, R109, R110, and R112. The predicted sound levels at the varying optimized height was ranged from 56 to 65 db(a) for 1B. The insertion loss per receiver at the varying optimized heights was 7 db for R3 (1 DU), 4 db for R102 (2 DU), 7 db for R103 (1 DU), 7 db for R104 (1 DU), 2 db for R105 (2 DU), 3 db for R109 (3 DU), 7 db for R110 (2 DU), and 8 db for R112 (2 DU). 1B is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimal 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. A Second Run 1A was considered only for Site R100 in an attempt to mitigate noise at R100 without concern for non impacted receptors, to see if a reasonable cost design could be achieved. The predicted sound level at the varying optimized height was 65 db(a) for 1A. The insertion loss per receiver at the varying optimized heights was 6 for R100 (1 DU). 1A is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimal 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. In summary, the feasibility study determined the Maximum Height design option to be feasible for 1AB. 1AB is not feasible for the Line-of-Sight design option. Optimized Height Design s 1A, 1A (second run), and 1B were determined to be feasible (Table 5). For each barrier design a reasonableness study was performed. 1AB, Maximum Height, has a total cost of $2,375,000 or $84,821 per benefited dwelling unit. This cost exceeds the $50,000 maximum allowable per FHWA and PennDOT s Publication #24. 1AB, Line of Sight Height, has a total cost of $641,475 or $80,184 per benefited dwelling unit. This cost exceeds the $50,000 maximum allowable per FHWA and PennDOT s Publication #24. 1A Optimized Height has a total cost of $169,300 or $169,300 per dwelling unit. 1A (second run) Optimized Height has a total cost of $161,525 or 161,525 per benefited dwelling unit. 1B Optimized Height has a total cost of $696,475 or Lansdale Noise Analysis Report 24
$69,647 per benefited dwelling unit. All optimized height barriers costs exceed the $50,000 maximum allowable per FHWA and PennDOT s Publication #24. (Tables 3A-3C) In summary, the total cost of the feasible options (s 1AB maximum height, and optimized height options for 1A and 1A (second run), 1B) have been determined to exceed the maximum allowable reasonable cost criteria, and are determined not reasonable for all s (Table 5). Although sound levels at these locations exceed the NAC criteria as shown in Table 2, none of the barrier designs for warranted noise mitigation meet the feasibility and reasonableness criteria as defined in PennDOT s Publication #24. 6-LANE OPTION Design Option 1: Maximum Height One maximum height barrier ( 1AB) was considered for Sites R100, R2, M2, R3, R102, R103, R104, R105, R109, R110, and R112 at a height of 20 feet from end to end with the exception of on-structure barriers which were at a maximum allowable height of 14.00 feet (see Table 4A for mitigated sound levels and impacted vs. benefited receivers). The predicted sound levels at the maximum wall height ranged from 56 to 62 db(a) for 1AB. The insertion loss per receiver, at maximum wall height was 9 db for R100 (1 DU), 6 db for R2 (4 DU), 5 db for M2 (11 DU), 13 db for R3 (1 DU), 8 db for R102 (2 DU), 9 db for R103 (1 DU), 9 db for R104 (1 DU), 4 db for R105 (2 DU), 8 db for R109 (3 DU), 12 db for R110 (2 DU), and 10 for R112 (2 DU). 1AB is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimal 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. Design Option 2: Line of Sight One line of sight barrier ( 1AB) was considered for Sites R100, R2, M2, R3, R102, R103, R104, R105, R109, R110, and R112 at varying heights from end to end (see Table 4B for mitigated sound levels and impacted vs. benefited receivers). The predicted sound levels at the varying line of sight heights ranged from 57 to 68 db(a). The insertion loss per receiver, at the varying line of sight heights was 5 db for R100 (1 DU), 2 db for R2 (4 DU), 1 db for M2 (11 DU), 6 db for R3 (1 DU), 3 db for R102 (2 DU), 5 db for R103 (1 DU), 7 db for R104 (1 DU), 2 db for R105 (2 DU), 2 db for R109 (3 DU), 6 db for R110 (2 DU), and 6 for R112 (2 DU). 1AB is not feasible since it does not reduce sound levels below the 66 db(a) NAC approach criteria and achieve the minimal 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. Design Option 3: Optimized Height Two optimized height barriers were considered at varying heights from end to end (Table 4C). 1A was considered for Site R100, M2 and R2. The predicted sound levels at the varying optimized height was ranged from 60 to 65 db(a) for 1A (see Table 4C for mitigated sound levels and impacted vs. benefited receivers). The insertion loss per receiver at the varying optimized heights was 6 for R100 (1 DU), 1 for M2 (11 DU), and 2 for R2 (4 DU). 1A is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves Lansdale Noise Analysis Report 25
the minimal 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. 1B was considered for impacted Sites R3, R102, R103, R104, R105, R109, R110, and R112. The predicted sound levels at the varying optimized height was ranged from 56 to 65 db(a) for 1B. The insertion loss per receiver at the varying optimized heights was 9 db for R3 (1 DU), 4 db for R102 (2 DU), 6 db for R103 (1 DU), 7 db for R104 (1 DU), 2 db for R105 (2 DU), 3 db for R109 (3 DU), 8 db for R110 (2 DU), and 8 db for R112 (2 DU). 1B is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimal 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. A Second Run 1A was considered only for on Site R100 in an attempt to mitigate noise at R100 without concern for non impacted receptors, to see if reasonable cost could be achieved. The predicted sound levels at the varying optimized height was 65 db(a) for 1A. The insertion loss per receiver at the varying optimized heights was 6 for R100 (1 DU). 1A is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimum 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. In summary, the feasibility study determined the Maximum Height design option to be feasible for 1AB. 1AB is not feasible for the Line-of-Sight design option. Optimized Height Design s 1A, 1A (second run), and 1B were determined to be feasible (Table 6). For each barrier design a reasonableness study was performed. 1AB, Maximum Height, has a total cost of $2,375,000 or $84,821 per benefited dwelling unit. This cost exceeds the $50,000 maximum allowable per FHWA and PennDOT s Publication #24. 1AB, Line of Sight Height, has a total cost of $654,150 or $81,768 per benefited dwelling unit. This cost exceeds the $50,000 maximum allowable per FHWA and PennDOT s Publication #24. 1A Optimized Height has a total cost of $165,275 or $165,275 per dwelling unit. 1A (second run) Optimized Height has a total cost of $156,550 for 156,550 per benefited dwelling unit. 1B Optimized Height has a total cost of $695,225 or $69,522 per benefited dwelling unit. All optimized height barriers costs exceed the $50,000 maximum allowable per FHWA and PennDOT s Publication #24. (Table 4A-4C) In summary, the total cost of the feasible options for s 1AB maximum height, and 1A, 1A second run, and 1B optimized height have been determine to exceed the maximum allowable reasonable cost criteria, and are determined to be not reasonable for all s (Table 6). Although sound levels at these location exceed the NAC criteria as shown in Table 2, none of the barrier designs for warranted noise mitigation meet the feasibility and reasonableness criteria as defined in PennDOT s Publication #24. E. NSA 5 There are no sensitive receptors located in NSA 5. Lansdale Noise Analysis Report 26
F. NSA 6 Design year Build noise levels were predicted to range between 71 to 78 db(a) for the 4-Lane Option and 71 to 78 db(a) for the 6-Lane Option within the limits of NSA 6, at Sites R200 and R201 representing approximately two DUs (Table 2). This is an increase from the existing sound level ranges of 67 to 75 db(a). Since predicated noise levels are greater than the 66 db(a) NAC approach criteria for Sites R20 and R201 in this NSA, mitigation consideration is warranted. G. NSA 7 Design year Build noise levels were predicted to be in the range from 64 to 73 db(a) for the 4- Lane Option and 64 to 74 db(a) for the 6-Lane Option within the limits of NSA 7, at Sites M3, R1, R114, R116, R118, and R119 representing approximately eleven DUs (Table 2). This is an increase from the existing sound levels at four of the six sites. Since predicated noise levels are greater than the 66 db(a) NAC approach criteria for Sites M3, R1, R114, R116, and R119 in this NSA, mitigation consideration is warranted. Since the impacted sites located in NSA 6 and 7 are within close proximity there was an overlap of the s. Therefore, one Maximum Height and one Line of Sight ( 2AB) were analyzed for both NSA 6 and 7 impacted receivers. An Optimized Height was also analyzed for the impacted receivers; however, the optimization divided the one long barrier into two smaller optimized barriers. 2A provides mitigation in NSA 6 for Sites R200 and R201, and R1 within NSA 7. 1B provides mitigation in NSA 7 for Sites R114, R116, R118, R119, and M3. 4-LANE OPTION Design Option 1: Maximum Height One maximum height barrier ( 2AB) was considered for Sites R200, R201, R1, R114, R116, R118, R119, and M3 at a height of 20.00 feet from end to end with the exception of onstructure barriers which were at a maximum allowable height of 14.00 feet (see Table 3A for mitigated sound levels and impacted vs. benefited receivers). The predicted sound levels at the maximum wall height ranged from 58 to 67 db(a) for 2AB. The insertion loss per receiver, at maximum wall height was 11 db for R200 (1 DU), 11 db for R201 (1 DU), 11 db for R1 (1 DU), 8 db for R114 (1 DU), 11 db for R116 (5 DU), 7 db for R118 (2 DU), 10 db for R119 (1 DU), and 8 db for M3 (1 DU). 2AB is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimum 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. Lansdale Noise Analysis Report 27
Design Option 2: Line of Sight One line of sight barrier ( 2AB) was considered for R200, R201, R1 R114, R116, R118, R119, and M3 at varying heights from end to end (see Table 3B for mitigated sound levels and impacted vs. benefited receivers). The predicted sound levels at the varying line of sight heights ranged from 62 to 69 db(a). The insertion loss per receiver, at the varying line of sight heights was 9 db for R200 (1 DU), 5 db for R201 (1 DU), 5 db for R1 (1 DU), 1 db for R114 (1 DU), 3 db for R116 (5 DU), 2 db for R118 (2 DU), 4 db for R119 (1 DU), and 2 db for M3 (1 DU). 2AB is not feasible since it does not reduce sound levels below the 66 db(a) NAC approach criteria nor does it achieve the minimum 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. Design Option 3: Optimized Height Two optimized height barriers were considered at varying heights from end to end (Table 3C). 2A was considered for Sites R200, R201 and R1. The predicted sound levels at the varying optimized height was ranged from 65 to 70 db(a) for 1A (see Table 3C for mitigated sound levels and impacted vs. benefited receivers). The insertion loss per receiver at the varying optimized heights was 9 db for R200 (1 DU), 6 db for R201 (1 DU), and 7 db for R1 (1 DU). 2A is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimum 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. 2B was considered for Sites R114, R116, R118, R119, and M3. The predicted sound levels at the varying optimized height was ranged from 61 to 65 db(a) for 2B. The insertion loss per receiver at the varying optimized heights was 2 db for R114 (1 DU), 7 db for R116 (5 DU), 4 db for R118 (2 DU), 6 db for R119 (1 DU), and 5 db for M3 (1 DU). 2B is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimum 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. In summary, the feasibility study determined the Maximum Height design option to be feasible for 2AB. 2AB is not feasible for the Line-of-Sight design option. Optimized Height Design s 2A and 2B were determined to be feasible (Table 5). For each barrier design a reasonableness study was performed. 2AB, Maximum Height, has a total cost of $2,616,000 or $201,230 per benefited dwelling unit. This cost exceeds the $50,000 maximum allowable per FHWA and PennDOT s Publication #24. 2AB, Line of Sight Height, has a total cost of $603,075 or $67,008 per benefited dwelling unit. This cost exceeds the $50,000 maximum allowable per FHWA and PennDOT s Publication #24. 2A Optimized Height has a total cost of $336,900 or $112,300 per benefited dwelling unit. 2B Optimized Height has a total cost of $581,850 or $83,121 per benefited dwelling unit. All Optimized Height s costs exceed the $50,000 maximum allowable per FHWA and PennDOT s Publication #24. (Tables 3A-3C) Lansdale Noise Analysis Report 28
In summary, the total cost of the feasible options for s 2AB maximum height, and 2A and 2B optimized height barriers have been determined to exceed the maximum allowable reasonable cost criteria, and are determined to be not reasonable for all s (Table 5). Although sound levels at these location exceed the NAC criteria as shown in Table 2, none of the barrier designs for warranted noise mitigation meet the feasibility and reasonableness criteria as defined in PennDOT s Publication #24. 6-LANE OPTION Design Option 1: Maximum Height One maximum height barrier ( 2AB) was considered for Sites R200, R201, R1, R114, R116, R118, R119, and M3 at a height of 20.00 feet from end to end with the exception of on structure barriers which were at a maximum allowable height of 14.00 feet (see Table 4A for mitigated sound levels and impacted vs. benefited receivers). The predicted sound levels at the maximum wall height ranged from 57 to 67 db(a) for 2AB. The insertion loss per receiver at maximum wall height was 11 db for R200 (1 DU), 11 db for R201 (1 DU), 11 db for R1 (1 DU), 8 db for R114 (1 DU), 12 db for R116 (5 DU), 7 db for R118 (2 DU), 11 db for R119 (1 DU), and 9 db for M3 (1 DU). 2AB is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimum 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. Design Option 2: Line of Sight One line of sight barrier ( 2AB) was considered for R200, R201, R1 R114, R116, R118, R119, and M3 at varying heights from end to end (see Table 4B for mitigated sound levels and impacted vs. benefited receivers). The predicted sound levels at the varying line of sight heights ranged from 62 to 70 db(a). The insertion loss per receiver, at the varying line of sight heights was 9 db for R200 (1 DU), 5 db for R201 (1 DU), 5 db for R1 (1 DU), 2 db for R114 (1 DU), 4 db for R116 (5 DU), 2 db for R118 (2 DU), 6 db for R119 (1 DU), and 3 db for M3 (1 DU). 2AB is not feasible since it does not reduce sound levels below the 66 db(a) NAC approach criteria nor does it achieve the minimum 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. Design Option 3: Optimized Height Two optimized height barriers were considered at varying heights from end to end (Table 4C). 2A was considered for impacted Sites R200, R201 and R1. The predicted sound levels at the varying optimized height was ranged from 65 to 70 db(a) for 1A (see Table 4C for mitigated sound levels and impacted vs. benefited receivers). The insertion loss per receiver at the varying optimized heights was 9 db for R200 (1 DU), 6 db for R201 (1 DU), and 7 db for R1 (1 DU). 2A is feasible since it reduces sound levels below the 66 db(a) NAC approach criteria and achieves the minimum 5 db insertion loss at the majority of the impacted receptor units as required by PennDOT s Publication #24. Lansdale Noise Analysis Report 29