The Air Quality at Intersections - Lab Report Example

DD Month YYYY Environmental Analysis EXECUTIVE SUMMARY The paper evaluates the impact of air quality at 4 way intersections where vehicular traffic causes or contributes to a rising emission of Carbon II oxide. The purpose of this report is to a scientifically accepted method to estimate the impact of air quality at intersection to find out if the effect exceed the NAAQS for Carbon Monoxide. The National Ambient Air Quality Standards for Carbon II oxide include 35 for 1 hours and 9 for 8 hours. The project is appropriate for analyses of project level according to the State Implementation Plans. The guidance may also be applicable to the Environmental Impact Statement. Development projects like intersection reconfigurations and streets and other construction projects that could affect the patterns of traffic will need the assessment of air quality impact. For such literatures, the impact of the projects on congestion, traffic and subsequent air quality effects need to be studied. The paper therefore, provide guidance to apply emission and dispersion modeling methods for the analyses. INTRODUCTION Evaluating the impact of air quality needs additional incremental effect of the intersection to levels of background ambient at the construction site and then compare NAAQS. The background Carbon II Oxide concentration are as a result of area wide mobile and the stationery emissions sources. Emphasis in the document is based on the intersections. The analysis intersection will be chosen from the intersection whose conditions will be suspected to be conducive to impacts of high concentration. For the analyses of project level, the criteria for the intersection is dependent on if the project has the ability of creating the impact of adverse air quality by increasing traffic or reducing the distance from the receptors. The overall procedure is important for the consistent analysis and selection of the intersections. Some of the procedures includes gathering of data, screening of intersections to determine the additional analysis, ranking of screened intersection, computation of the conditions of traffic flow, selection of the receptor locations, and using dispersion models in calculating the estimated concentration, and the overall tabulation of the concentration due to background and intersection (Cooper, 1313). SCOPE OF STUDY The air quality experiment determines the objective of air quality due to intersections. The paper will dictate the analysis level, amount of effort, and the resources required. If the review of the project permit is involved the specific objective is to assess the potential of worst case for exceeding either the 8 hour or 1 hours Carbon II Oxide NAAQA. The data set is important for formulating the inputs to the procedures of modeling. Some of the items that should be incorporated includes scaled map for intersection, traffic engineering characteristics, total traffic speeds and volumes, link specification and coordinates, local CO and Background, meteorological data, and miscellaneous demographic data. The project scope required consideration of various intersections (Paul and Johnson, 75). The steps in the study provided a logical sequence of analysis permitting a quicker review of intersections to find out which are most likely to have a higher impact of the ambient air quality based on the traffic volumes using the delay of traffic calculations. The two factor, vehicle number, vehicle delay, and are related to the emission production at the point of intersection and therefore offer a direct indicator of the related impacts of air quality. The calculation of level of service provided an overall rating for intersections. The intersection were then calculated with the future or current level of services (Woehlck, Dunning and Ruiz, 1230). PROJECT DESCRIPTION (250 words) No Build: Alternative I The No-Build alternative includes the transportation improvements that are included in LRTP. The conditions in 2035 are outlined in the forecast of traffic for the No-Build alternative in 2035, which would forecast the flow of traffic to be affected by the confined roadway capacity and the rising traffic volumes. These concept would not entail any improvement, beyond those found in No-Build scenario that would otherwise increase the speed of travel or reduce the time of travel over the present forecast conditions. For this reason it will not improve the mobility at all trips within. The extension project area of study during the peak travel time. Build Alternative: Alternative II There are various types of concepts that were evaluated and considered, including the improvement on the existing constructions and roadways of new location roadways, Additional hybrid concepts were considered. This consisted of the construction section of projects as new roadways and the improved existing roadways for the other sections. The build alternative would widen the present expressways in the project area of study, upgrade a fundamental parallel arterial roadway consisting of combinations of this improvements. Major routes of travel through the area of study include the four lane roadway. There is no arterial facilities that offer a parallel roadway to new location alternative. Various variation of the Improve Existing Roadways Alternative Concept was also considered (Cooper, 1313). CRITERIA FOR DETERMINING IMPACTS A lot has been written based on the selection of the receptor location for the analysis of the impact of receptor location. The general criteria for determining the impact include placing the expected 1 hour and 8 hour maximum concentrations. Secondly, it involves places where the public can easily access over the time period that is specified by NAAQs, and thirdly, the reasonableness. Reasonableness is based on the proximity to intersection but not on the roadway itself. Both the specific locations and the general locations are recommended for the analysis of the intersection. The objective of the paper is too offer guidance for the estimation of the maximum carbon II oxide near the intersection (Paul and Johnson, 52). The roadways are not receptor sites. In addition, the receptor should be positioned within 3 meter of the roadways which comprises the intersection where the turbulence of vehicle do not allow current model to make the concentration estimates. It there exists a structure within the 3 meter some, then the regional office of the EPA need to be contact to determine the right siting for the receptor. In most studies, the receptor need to be positioned at every approach of where the queues was developed. In all the cases, the receptors need to be positioned on the sidewalks or right of way limit in circumstances where there is no sidewalk (Khaenamkaew, 423). METHODOLOGY The methodology provides a selection and ranking procedures to enable the discernment of the intersection that tends to be a potential spot with high CO concentration. The guidance is used primarily to find out the potential hotspots in SIP analysis, but will be important for project level when more than two intersections are affected. The intersections are chosen for analysis based on the study objectives. All the signalized intersections are then reviewed to create the negative impact of air quality by increase in traffic and the reduction in the roadway distance starting from receptors. The choice of intersections for modeling is based on the ranking protocol. Carbon Monoxide Modeling The Level of Service measured the operating conditions found at the intersection and how the conditional affected the delay and the traffic flow. The LOS measured the combination of the signal timing, traffic volume, and the relayed delay and congestion. This is related to the physical characteristic and the operating conditions that happen when the transaction carries the variable traffic volume. The level of service A described the operations that have a lower delay. The LOS B described the operations that have delays ranging from 5.1 to 15.0 seconds for each vehicle. LOS C described the operations that have delays ranging from 15.1 to 25.0. LOS D described the operations that have delays ranging from 25.1 to 40.0 sec for each vehicle. LOS E described some of the operation that have delays ranging from 40.1 to 40 sec for every vehicle. LOS F described the operation that have delays that exceed 60 sec for every vehicle. MOBILE5A Emission Modeling The domestic air quality has compiled the localized cold and hot start rates which were used as one of the input data to MOBILE. The hourly temperatures used in the analysis were used in MOBILE. Also the domestic recommended values for the Inspection/Maintenance and Anti-tampering program specification were also used. No domestic data were available for the annual mileage and VMT accumulation rates by registration distributions and age, therefore MOBILE defaults were also used. The base RVP is assumed as 9.0 psi and the year is 1995. The intersection and free flow speed for every departure link and approach as determined by engineers was taken to be 20 mph. the mobile input file is as shown in the appendix and its output file. From the output file, the queue link emission and free flow are obtained that is 17.2 g/mi as free flow and 259.1 g/hr for queue. CAL3QHC Atmospheric Dispersion Modeling The intersection at two location is located in suburban portion of place near the small office complexes. The recommended surface roughness for the land use is 175 cm. The main and local street intersection is characterized by the main street with a daily traffic of 18400 vehicle and the peak hour volume of 1500 vehicles in every direction. The cross street is a single way toward the east with a mean traffic volume of 9200 vehicles and the peak hour volume comprising of 800 vehicles. The dispersion modelling comprised of the intersection geometry that include the coordinate endpoints of every link, the model assumed the width and the location of receptors. Sensitive Receiver Selection The objective of the paper is too offer guidance for the estimation of the maximum carbon II oxide near the intersection. The roadways are not receptor sites. In addition, the receptor should be positioned within 3 meter of the roadways which comprises the intersection where the turbulence of vehicle do not allow current model to make the concentration estimates. It there exists a structure within the 3 meter some, then the regional office of the EPA need to be contact to determine the right siting for the receptor. In most studies, the receptor need to be positioned at every approach of where the queues was developed. In all the cases, the receptors need to be positioned on the sidewalks or right of way limit in circumstances where there is no sidewalk. RESULTS Both the alternatives resulted in the construction of a single lance in every direction along the lane. Both the build alternatives would involve various modification to the existing structure to accommodate the expressed lane. No Build Alternative The No-Build alternative concept include the minor improvements that are short term. The improvements include maintenance and safety improvement that maintained a continuous operation of the present roadway network. It was used as a foundation comparative alternative for the design year. The concept assumed the transportation in the project research area will continue develop. The purpose of the alternative is to reduce the traffic congestion on the present roadways in the study areas. The conditions projected by developing the planned improvement to the transportation network that is included in LRTP. This concept therefore, would not minimize the mean daily VHT, the congested VMT over the present forecast conditions. For this reason, it will not reduce the forecast traffic congestion in all the present roadway network in the area of study. The No-Build Alternative concept will not complete the Outer Loop System and the faster access to I-540 network for people that live in the study area. Therefore, it will not improve the linkage system found in the transportation network. Build Alternative Various types of the build alternative concepts were evaluated and considered. Such alternative include improvement of the present construction and roadways of new location roadways. Additionally, some of the hybrid concepts were considered. This consisted of the construction part of the project as new region roadway and improving the present roadway for the other sections. Comprehensive results for the paper are shown in the appendix. CONCLUSION The calculation of the 8 hour estimates from the 1 hour estimates is a method used since 1975. The primary focus for the calculation was based on the computation on the relationship between the 8 hour and 1 hour meteorological and volumes conditions. Since the ration for the 8 hour and 1 hour estimates represented the combination of the changes in both the meteorological conditions and the traffic conditions. The ratio of the measured concentrations need to be used to find out the persistence factor, since the evaluation data included the effect in both the meteorological and traffic conditions. The preferred method is using the monitoring data. The persistence factor is based on the values that are gotten using the 8 hour and 1 hour measured carbon II oxide within the period (Woehlck, Dunning and Ruiz, 1234). A lot has been written based on the selection of the receptor location for the analysis of the impact of receptor location. The general criteria for determining the impact include placing the expected 1 hour and 8 hour maximum concentrations. Secondly, it involves places where the public can easily access over the time period that is specified by NAAQs, and thirdly, the reasonableness. The persistence factor is calculated for every of the ten highest no-overlapping concentrations gotten from the last 3 carbon II Oxide season of the evaluation data. If the monitoring data are not obtained then using two data seasons is allowed. In this case we use the default factor of 0.7. The 0.7 factor is a persistence factor that is based on the research of the monitoring data in the entire regions of that nation. Therefore, EPA ascertains using the 0.7 persistence factor in a domestic region where the monitoring data are not found. References Cooper, C. David. Indirect Source Impact Analysis-Carbon Monoxide Modeling. JAPCA 37.11 (1987): 1308-1313. Web. Khaenamkaew,. Annual Concentration Report And Emission Sources Analysis Of The Air Pollutants Measured By The Air Quality Monitoring Station. American Journal of Environmental Sciences7.5 (2011): 415-423. Web. Paul, Roy A, and Ted Johnson. The NAAQS Exposure Model (NEM) Applied To Carbon Monoxide. Research Triangle Park, NC: U.S. Environmental Protection Agency, Office of Air and Radiation, Office of Air Quality Planning and Standards, 1985. Print. Woehlck, Harvey J., Marshall B. Dunning, and Franklin Ruiz. Mathematical Modeling Of Carbon Monoxide Exposures. Anesthesiology 89.Supplement (1998): 1234A. Web. Appendix Input File: MOBILE - Main St. at Local St. 1 1 1 1 1 2 1 2 1 1 2 4 2 2 1 1 82 30 60 20 0. o. 75. 3 1 2222 1 11 94 60 20 2222 21 75.0 22112121 1 95 20.0 55.0 18.9 25.3 18.9 C55.0 55.0 9.0 9.0 95 Output File: No Build or Build Alternative] 2035 Alternatives Analysis PM Travel Times Origin: Raleigh‐Durham Airport (Airport Blvd. & International Dr.) Alternatives Destination No‐Build Build Hybrid 1 Hybrid 2 Hybrid 3 Improve Existing 1 Improve Existing 2A Improve Existing 2B Improve Existing 3A Improve Existing 3B Holly Springs 33 32 32 35 32 33 35 33 32 32 Fuquay‐Varina 45 41 41 41 41 45 41 44 42 42 Garner 47 41 41 44 41 42 44 45 41 42 Clayton 70 57 59 67 58 62 67 68 60 65 Knightdale 59 57 54 57 55 54 57 56 56 56 E Wake Co. 66 59 61 63 60 62 65 64 62 63 NW John. Co. 69 48 48 57 52 62 56 64 52 56 RTP 10 9 9 10 9 10 10 9 10 10 Brier Creek 10 10 10 10 10 10 10 10 10 10 Durham 18 18 18 18 18 18 18 18 18 18 Cary 18 18 18 18 18 19 18 18 18 18 2035 Alternatives Analysis AM Travel Times Origin: Brier Creek (US 70 & Brier Creek Pkwy.) Alternatives Destination No‐Build Build Hybrid 1 Hybrid 2 Hybrid 3 Improve Existing 1 Improve Existing 2A Improve Existing 2B Improve Existing 3A Improve Existing 3B Holly Springs 25 25 25 24 25 25 24 25 25 25 Fuquay‐Varina 28 28 28 27 28 28 27 28 28 28 Garner 25 25 25 25 25 25 25 25 25 25 Clayton 35 35 35 34 35 35 35 35 35 35 Knightdale 23 24 24 24 24 24 24 24 24 24 E Wake Co. 28 28 28 28 28 28 28 28 28 28 NW John. Co. 34 34 34 34 34 34 34 34 34 34 RTP 9 10 10 10 10 10 10 10 10 10 RDU 9 9 9 9 9 9 9 9 9 9 Durham 15 15 15 15 15 15 15 15 15 15 Cary 15 15 15 15 15 15 15 15 15 15 2035 Alternatives Analysis PM Travel Times Origin: Brier Creek (US 70 & Brier Creek Pkwy.) Alternatives Destination No‐Build Build Hybrid 1 Hybrid 2 Hybrid 3 Improve Existing 1 Improve Existing 2A Improve Existing 2B Improve Existing 3A Improve Existing 3B Holly Springs 32 31 31 34 31 32 34 32 32 31 Fuquay‐Varina 45 40 40 40 41 44 40 43 41 41 Garner 49 43 43 46 43 44 47 48 43 45 Clayton 73 56 58 66 57 64 68 70 59 65 Knightdale 54 53 50 53 51 49 53 52 51 51 E Wake Co. 61 58 57 59 56 57 61 59 58 59 NW John. Co. 71 47 47 56 51 64 56 63 52 55 RTP 9 9 9 9 9 9 9 9 9 9 RDU 9 9 9 9 9 9 9 9 9 9 Durham 14 14 14 14 14 14 14 14 14 14 Cary 20 20 20 20 20 21 20 20 20 20 Read More