Office of Planning, Environment, & Realty (HEP)

Planning • **Environment** • Real Estate

- CHAPTER 1. INTRODUCTION
- CHAPTER 2. EXAMINATION OF FEASIBILITY AND REASONABLENESS FACTORS
- 2.1 FACTORS AND FACTOR COMBINATIONS AFFECTING NOISE ABATEMENT DECISIONS
- 2.1.1 Feasibility Noise Reduction
- 2.1.2 Feasibility Quantity
- 2.1.3 Benefited Noise Reduction
- 2.1.4 Noise Reduction Design Goal (NRDG)
- 2.1.5 Noise Reduction Design Goal (NRDG) Quantity
- 2.1.6 Cost Effectiveness (CE)
- 2.1.7 Noise Reduction Design Goal (NRDG) and Feasibility Quantity
- 2.1.8 Benefited Noise Reduction and Feasibility Quantity
- 2.1.9 Noise Reduction Design Goal (NRDG) and Benefited Noise Reduction
- 2.1.10 Cost per Benefited Receptor (CPBR) and Benefited Noise Reduction
- 2.1.11 Cost per Benefited Receptor (CPBR) and Noise Reduction Design Goal (NRDG)
- 2.1.12 Normalized Cost per Benefited Receptor (CPBR), Area per Benefited Receptor (APBR) and Noise Reduction Design Goal (NRDG)
- 2.1.13 Normalized CPBR, APBR and Benefited Reduction
- 2.1.14 Summary of Ranges in the Four Factors

- 2.2 IDENTIFYING OPTIMIZED COMBINATIONS OF VALUES
- 2.3 CHAPTER SUMMARY

- 2.1 FACTORS AND FACTOR COMBINATIONS AFFECTING NOISE ABATEMENT DECISIONS
- CHAPTER 3. TESTING THE RESULTS FOR THE FOUR ABATEMENT FEASIBILITY AND REASONABLENESS FACTORS
- CHAPTER 4. CONCLUSIONS

- Figure 1: Number of SHA policy values as a function of Area per Benefited Receptor or normalized Cost per Benefited Receptor (includes low and high values for policies with ranges)
- Figure 2: SHA values for CPBR and corresponding barrier area calculated from unit cost
- Figure 3: SHA values for CPBR and corresponding barrier unit cost
- Figure 4: SHA values for barrier area calculated from unit cost and corresponding abatement unit cost
- Figure 5: Relationship between minimum number and percentages of first-row and all impacts
- Figure 6: Neighborhood adjacent to highway
- Figure 7: Plan view (top) and cross-sectional view (bottom) of roadways and noise barrier portion of FHWA TNM model for sensitivity test cases
- Figure 8: Sketches of receptor scenarios used in modeling the sensitivity test cases for first-row receptors 90 feet (top) and 140 feet (bottom) from barrier.
- Figure 9: TNM plan view plots of receptor scenarios in FHWA TNM model for sensitivity test cases: 140 feet back (top) and 90 feet back (bottom)
- Figure 10: Upper left portion of reasonableness decision array for the sensitivity test cases: NRDG of 7 dB, Benefited Noise Reduction of 5 dB, 50-ft receptor spacing, 50-ft distance back to first-row (90 ft from barrier), and mostly one-row cases
- Figure 11: Decision patterns indicated by color bands in portion of reasonableness array for 50-ft receptor spacing, NRDG of 7 dB and Benefited Noise Reductions of 5 dB (upper half) and 6 dB (lower half)
- Figure 12: Lower right portion of reasonableness decision array for the sensitivity test cases: NRDG of 10 dB, Benefited Noise Reduction of 10 dB, 200-ft receptor spacing, 100-ft distance back to first-row (140 ft from barrier) and one-, two- and three-row cases
- Figure 13: Reasonableness decision array for NRDG for number of benefited receptors of 1 (top), 2 (middle), or 3 (bottom)
- Figure 14: Reasonableness decision array for NRDG for percentage of first-row benefited receptors, divided into four horizontal sections for values of 10%, 50%, 67%, and 80%
- Figure 15: Reasonableness decision array for NRDG for percentage of all benefited receptors divided into five horizontal sections for values of 10%, 25%, 50%, 67%, and 80%
- Figure 16: Portion of reasonableness decision array for NRDG of 7-10 dB for 80% of all benefited receptors for 50-ft receptor spacing for 1, 2, and 3 rows of receptors
- Figure 17: Reasonableness Decision Array, APBR = 500 SF/benefited receptor
- Figure 18: Reasonableness Decision Array, APBR = 1,000 SF/benefited receptor
- Figure 19: Reasonableness Decision Array, APBR = 1,500 SF/benefited receptor
- Figure 20: Reasonableness Decision Array, APBR = 2,000 SF/benefited receptor
- Figure 21: Reasonableness Decision Array, APBR = 2,800 SF/benefited receptor
- Figure 22: Study Area A: Ten-lane highway with dense development close to the highway
- Figure 23: Study Area B: Six-lane highway with two rows of closely-spaced houses angling away from the highway
- Figure 24: Study Area C: Ten-lane highway with medium-density houses curving away from the highway
- Figure 25: Study Area D: Eight-lane highway with low-density houses set back from the highway

- Table 1: Combinations of Feasibility Quantity and Feasibility Noise Reduction
- Table 2: Benefited Noise Reduction Values
- Table 3: Noise Reduction Design Goal (NRDG)
- Table 4: Combinations of NRDG and NRDG Quantity
- Table 5: Cost Effectiveness (CE) Criteria
- Table 6: Combinations of Noise Reduction Design Goal (NRDG) and Feasibility Quantity
- Table 7: Combinations of Benefited Noise Reduction and Feasibility Quantity
- Table 8: Combinations of Noise Reduction Design Goal (NRDG) and Benefited Noise Reduction
- Table 9: Combinations of Noise Reduction Design Goal (NRDG), NRDG Quantity, and Benefited Noise Reduction
- Table 10: Combinations of Cost per Benefited Receptor (CPBR), Area per Benefited Receptor (APBR) and Benefited Noise Reduction
- Table 11: Combinations of CPBR, APBR and NRDG
- Table 12: Combinations of Normalized CPBR or APBR and NRDG, Ranked by APBR
- Table 13: Combinations of Normalized CPBR or APBR and Benefited Reduction Used by SHAs, Ranked by APBR
- Table 14: Noise Reduction Design Goal Example Results
- Table 15: Relationships of Feasibility and Reasonableness Factors to Barrier Likelihood
- Table 16: Relationships of Feasibility and Reasonableness Factors to Barrier Decision
- Table 17: Combinations of Factors More Likely to Result in Negative Abatement Decisions
- Table 18: Combinations of Factors More Likely to Result in Positive Abatement Decisions
- Table 19: Summary Table of Case Characteristics
- Table 20: Feasibility Results for Study Area A: Ten-Lane Highway with Dense Development Close to the Highway
- Table 21: Reasonableness Results for Study Area A: Ten-Lane Highway with Dense Development Close to the Highway
- Table 22: Feasibility Results for Study Area B: Six-Lane Highway with Two Rows of Closely-Spaced Houses Angling Away from Highway
- Table 23: Reasonableness Results for Study Area B: Six-Lane Highway with Two Rows of Closely-Spaced Houses Angling Away from Highway
- Table 24: Feasibility Results for Study Area C: Ten-Lane Highway with Medium-Density Houses Curving Away from Highway
- Table 25: Reasonableness Results for Study Area C: Ten-Lane Highway with Medium-Density Houses Curving Away from Highway
- Table 26: Feasibility Results for Study Area D: Eight-Lane Highway with Low-Density Houses Set Back from Highway
- Table 27: Reasonableness Results for Study Area D: Eight-Lane Highway with Low-Density Houses Set Back from Highway