Mayor's opinion (September 3, 1999) for Yokohama Shonan Road Environmental Impact Assessment Preparation Document

Ring Health Examination No. 92
September 3, 1999
Governor of Kanagawa Prefecture Hiroshi Okazaki
Hidenobu Takahide The Mayor of Yokohama

About opinion for "Yokohama Shonan road environmental impact assessment preparation book" (answer)

On June 14, 1999, we will respond to the title for which there was a request for opinion in the ring total No. 5 as attached.

In charge: Environmental Impact Assessment Section, Yokohama City Environmental Conservation Bureau
TEL： 045‐671‐2495、2479

Attachment

1 Basic matters

(1) Of the planned sites of the Yokohama Shonan Road (Taya-cho, Sakae-ku, Yokohama-shi-Jonan 1-chome, Fujisawa-shi) (hereinafter referred to as "this project"), the part that passes through the Yokohama city area is an urbanization adjustment area and densely populated houses However, the roadside environment due to this project is greatly changed, and this project is planned in some parts in contact with houses and kindergartens. In addition, the General Environment and Air Measurement Bureau near the planned site
Although the environmental standards for nitrogen dioxide have been achieved, on the other hand, since the environmental standards for the concentration of suspended particulate matter have not been achieved, sufficient environmental conservation measures must be taken to preserve the surrounding environment. Is required.

(2) It is said that the predicted value of nitrogen dioxide in 2010 will be improved from the current situation, but since there are uncertain factors about this value, we will enhance the ex-post survey and take environmental conservation measures according to the results There is a need to do it.

(3) The planned traffic volume for 2010 used in the forecast is estimated by a four-step estimation method based on the results of the 1990 National Traffic Situation Survey. Since changes in the socio-economic situation over the past 20 years have uncertain factors, the planned traffic volume also includes uncertain factors, and it is necessary to enhance ex-post surveys from this perspective.

2. Individual matters

(1) Construction plan

Oh, it is necessary to select the entrance of the construction vehicle and the location where the construction generated soil is carried out in consideration of the effects of noise and local communities, etc., and specifically describe it in the evaluation report.

B) In order to reduce air pollution, noise, etc. associated with running construction vehicles, it is necessary to reduce the total number of construction vehicles running.

(2) Air pollution

Oh, it is necessary to predict and evaluate suspended particulate matter associated with the car operation at the time of operation, and to describe it in the evaluation report.
In particular, consider the fine particulate matter (DEP) emitted from diesel vehicles.

B. In this project, more than 70% of the entire line has a tunnel structure and can be evaluated as a countermeasure against air pollution along the roadside. However, since exhaust gas inside the tunnel is intensively discharged from the ventilation station, capturing suspended particulate matter at this ventilation station is considered a very effective means. Therefore, in order to further protect the environment, it is necessary to plan the installation of a dust collector at the Sekiya Ventilation Center (tentative name) that can capture particles at the submicron level with high efficiency.

C. The average emission rate of the ventilation station is about 6 m / s, but it is necessary to increase the emission rate from the viewpoint of preventing down-wash and promoting more atmospheric diffusion.

(3) Water pollution

(A) The chemical solution injection method is based on the Ministry of Construction's “Provisional Guidelines for Construction Work Using the Chemical Liquid Injection Method”. It is necessary to prevent soil contamination from occurring.

The cleaning and drainage of the tunnel must be properly treated and discharged in consultation with related organizations.

(4) Noise and vibration

Oh, near the entrance of the construction area, it is assumed that the noise caused by the running of construction vehicles etc. will be large, so it is necessary to make predictions and evaluations and write them in the evaluation report.

B) In order to reduce construction noise and vibration around facilities that need to maintain calm, such as kindergartens, it is necessary to secure as much separation between the machine that is the source of noise and vibration and the building as much as possible, and also consider the operating hours. there is.

C) The noise associated with the driving of the car at the time of operation must be predicted and evaluated at the equivalent noise level and described in the evaluation report.

D) The noise at the time of operation does not take into account the reflected sound of elevated structures, etc., so it is necessary to consider and implement measures against reflected sound of structures.

(E) For places where sound insulation walls cannot be installed due to entry and exit of cars, etc., it is necessary to take measures such as low-noise pavement and implement appropriate management so that the effect is not reduced due to clogging.

F) Considering the uncertainty of planned traffic volume, etc., it may not be possible to achieve the environmental conservation target at the time of operation, so it is necessary to consider additional measures after operation.

(G) The joint part of the elevated structure may increase the vibration due to the driving of the car, so it is necessary to perform proper construction so that no steps are formed at the joint.

(5) Land subsidence

It is necessary to measure fluctuations in ground and groundwater from the earliest possible stage before the start of construction of Aton Nel, and reflect the measurement results in construction management.
In addition, the survey points must be selected in consideration of the location and depth of the tunnel as well as the distribution of alluvial layers.

It is necessary to conduct a survey of houses and structures before, during and after the completion of the tunnel construction, and reflect the results in construction management and surveys after the start of construction work.
In addition, the scope of the survey must be selected in consideration of the location and depth of the tunnel as well as the distribution of alluvial layers.

(6) Radio interference

For radio interference associated with this project, it is necessary to make effective use of newly installed joint reception facilities, etc., and actively improve the reception status.

(7) Sunshine obstruction

Based on the environmental conservation goal of "do not have a significant effect on the living environment" and "Contribution of expenses related to damage caused by shade caused by the installation of public facilities" (Notice of Secretary-General of the Ministry of Construction, 1976), Take appropriate measures as an environmental conservation measure, but it is not appropriate for an evaluation.
For this reason, regarding the impact of elevated structures on houses and crops, when the project is embodied, a time-specific shading map and an equal-time shading map are created using actual shading based on detailed design, and the effect is clarified. It is necessary to show the relevant residents after clarifying, and respond appropriately while considering the intentions of the residents.

(8) Water elephant

When drilling underground, it is necessary to ensure that the depletion of the surrounding wells due to the drop in the water level of groundwater does not affect daily life.

(A) Regarding rainwater drainage on the road surface, it is necessary to consider not to place a significant load on rivers.

(9) Plants and animals

Oh, in the preparation document, some plants that seem to have been planted are native species, so it is necessary to correct them in the evaluation report.

(B) According to the field survey, a goshawk flight has been confirmed around the planned site, so it is necessary to conduct a sufficient survey again before starting construction, check for nesting, and take appropriate measures.

C) It is necessary to minimize construction zones, construction roads, material storage areas, etc., and to reduce the impact on nature as much as possible.

(10) Local Communities

Oh, it is necessary to list in evaluation report about running route of construction vehicle and point where existing road is divided by construction, service.

B. It is necessary to decide on alternative roads associated with the operation of this project after sufficient consultation with local residents.

(11) Landscape

(A) In order to further reduce the feeling of oppression caused by the presence of elevated structures, consideration should be given to the design of structures, and consideration should be given to environmental facilities such as the maintenance of amenities such as water and greenery, and consideration should be given to the position of piers.

B. From the stage of structural design, it is necessary to consider not only harmony with the surrounding natural environment but also from the viewpoint of creating a new environment.

(12) Disasters

A. In the construction of the slope of Kojaku-cho, Totsuka-ku, it is necessary to use a construction method that gives due consideration to safety in order to prevent the collapse of the slope.

It is necessary to specifically describe evacuation methods in the event of a fire in the tunnel and measures to prevent the spread of the fire in the evaluation report.

3 Ex-post investigation

(1) When starting construction, it is necessary to verify the planned traffic volume based on the latest traffic volume survey at that time and take appropriate measures.

(2) After operation, it is necessary to investigate traffic volume, air pollution, noise, etc., and take necessary environmental conservation measures based on the results.

(3) Measurement of changes in ground and groundwater must be carried out continuously for a certain period of time after operation until the status of land subsidence is stable.

(4) It is necessary to prepare a post-survey plan such as monitoring and write it in the evaluation report.

Appendix

In the air environment of Yokohama City, in many parts of the city, environmental standards for nitrogen dioxide and suspended particulate matter concentration have not been achieved, and further improvement of the atmospheric environment is required, and exhaust gas from automobiles is a major factor in the emission of these pollutants.
In this project, the background concentration of nitrogen dioxide in 2010 is estimated based on the Kanagawa Prefecture Automobile Emissions Reduction Plan, and the achievement of this plan plays an important role in achieving environmental conservation targets. Therefore, it is important to ensure that the Kanagawa Prefecture Automobile Emissions Reduction Plan is implemented.
Also, given that diesel vehicles still have a high percentage of nitrogen oxides and suspended particulate matter emitted from automobiles, there is an urgent need to further promote emissions control from diesel vehicles. Furthermore, since highways like this project have a relatively high contamination rate of large diesel vehicles, the measures against diesel vehicles are considered to be particularly effective as environmental measures for this project.
From these perspectives, it is necessary to ensure that the specific measures outlined in the report on exhaust gas emissions of diesel vehicles (Third Report) of the Central Environment Council in December 1998 are implemented.