SEASONAL POLLUTION

seasonal pollution

The seasonal pollution is that kind of pollution that appears for a limited period of time but which can have longer time effects. Seasonal pollution appears as a result of the works for traffic safety maintenance during the winter (about 4 months) on the glaze and ice roads

The most frequently used substance is the sodium chloride. Each intervention upon the road can be translated as a 70 210Kg NaCl/km overflow on a two traffic lane road. These values will be higher in the case of the motorway. They will be different from one area to another depending on the weather conditions.

1. water

1.1.Sources of pollution

In the case of water, the substances and materials used preventively or curatively on the roads affected by glaze and ice are the main sources of pollution during the winter.

When the snow has melt, the resulted salt solution flows or is splashed on the sides by the traffic and spread on the neighboring land an/or into the natural waters.

2.1. the impact upon environment

The effects upon the subsoil water layer

The impact upon the subsoil water layers is manifested by the transfer of NaCl into these layers. The SETRA Study highlights that the Cl^- concentration in quantities close to 10 15 mg/l is the same for farther sources.

The Cl^- concentration is about 10 20 mg/l higher for an area larger than 100 km^2, and it is constant for 1 year. The chlorides accumulate between the 10-40 cm horizon within the first year.

Special attention needs to be paid to the NaCl quantity when the drinkable water supplying is made from the subsoil source, in order to keep the quality parameters within the limits imposed by the legislation in force.

The effects upon the surface water

The presence of the thaw salts as Cl^-, Na⁺ and Ca⁺⁺ ions has been noticed up to 100 m from the road. The chlorine ions contained in the salt have the property to reach the natural waters. The presence of the ions in the drinkable water sources is a very undesirable characteristic. 

The SETRA Studies have shown the presence of the chlorides in the receiver course in summer time as well and they can reach 11000 mg/l chlorides in the case where a quantity of 25 t NaCl/Km is used during the winter on a two lane road and a 10 km² area. This quantity doubles in the case of the motorway.

Generally the Cl^- concentration measured in the water courses does not exceed the admitted values; they are lower than 500 mg/l. The effect of the chlorides upon the benthic organisms is insignificant when the maximum limits are abided by.

The impact upon the surface and subsoil water layers depends on the quantity of salts that have been used. This quantity resides from the weather conditions specific for the respective area. The optimum dose of NaCl that should be used for an intervention, according to the special literature (B. Cososchi The Impact of Transport upon the Environment), is about 20 g/m² in case of prevention and about 40 g/m² in case of curative purpose for the thawing of the ice.

Special literature  Water Protection against Traffic Pollution  estimates the following average quantities used thawing in the case of the motorways:

v     A type area, characterized by hard winters: 30 t / year / km,

v     B type area, characterized by medium winters:15 t / year / km,

v     C type area, characterized by gentle winters: 5 t / year / km.

- It generally takes a 4 months period for the freeze/thaw prevention treatments. It can be supposed that from the point of view of the relief forms the motorway goes through the following types of areas:

plain on the Bucharest Banesti section,

hills on the Banesti Comarnic section,

mountain on the Comarnic Rasnov section,

hills on the Rasnov Codlea section.

In order to estimate the quantity of chlorides resulted from the thaw treatment they started from the simplifying hypothesis of its application in continuous flow for 4 months. 

The evaluation has been made depending on the type of the respective area and the weather conditions according to the following formula:

Table nr. 2.1. 1 The quantity of chlorides resulted from the application of the thaw treatment

Depending on the type of the area, the volume of pluvial waters for 1 km of a 4 lane motorway will be:

Table nr. 2.1. 2 Rain water flow

The rainwater quantity calculation has been made based on the formula:

Q_rainwater = ( S (m²) * annual average rainfalls (m) x rolling factor ) / 4 x 30 x 86400 s

K = 0,9 flowing factor for asphalt surfaces.

Actually, only part of the overall quantity representing the average flow for chlorides infiltrates into the soil, underground water or is evacuated into surface waters. An important part of the salts is projected by the wind or vehicles in the neighboring areas of the motorway.

3.1.environment protection measures

Among the most efficient measures for reducing pollution of the underground and surface waters, there are:

v     The sodium chloride, as well as the other materials used in winter must be stored in covered deposits and on waterproof surfaces, in order to avoid pollution by being washed away by the rainwater.

v     Optimal quantity of used salt: using the salt solution as preventive treatment seems to be a good solution for this purpose;

v     Protection of sensitive areas, by avoiding the use of high concentration substances.

Generally, the effect of defrosting salt on underground and surface waters is insignificant.

2. soIl

2.1. pollution sources

Seasonal pollution has a limited duration (approx. 4 months in winter), but its effects may be on longer time.

The salts used for defrosting may be: solid (NaCl, CaCl₂) or solution.

2.2.impact on the environment

Soil pollution may be the result of the infiltration of the rainwater that washes the motorway platform, washing away the defrosting substances.

After ice melting, the salt solution resulted flows or is projected laterally by the vehicles, spreading on the nearby land.

The studies performed have revealed the presence of defrosting salts, as Cl^-, Na⁺ and Ca⁺⁺ ions , up to 100 m away from the road.

Part of the salt quantity used will accumulate into the soil, between 10-40 cm in-depth. An important sodium characteristic is its relatively low mobility, being rapidly settled into the upper strata of the soil. However, we may consider that, in time, the new salt effect upon the soil surface leads to the displacement of the solid already settled during the previous winters, to deeper and less saturated strata.

2.3.environment protection measures

The rainwater washing the motorway platform are not directly drained onto the surrounding land, but into ditches and filtering installations. Therefore, the pollution risk is low.

It is recommendable to store the defrosting substances in covered deposits, on waterproof platforms. If the storing place is not covered, there will be built guard fences around the deposit, where the rainwater falling on the deposit is collected.

It is also recommendable to pay special attention to sensitive areas, with high accumulation capacity, by using optimal quantities of defrosting salts.

SECTION 1 BUCHAREST PLOIESTI

KM 53 KM 65

SECOND ROUTING ALTERNATIVE

Km 53 KM 65 2^nd routing alternative

One has taken into account two routing alternatives within the herein project,  for the southern area of the Municipality of Ploiesti.

The second Alternative, called The Barcanesti Alternative, has been studied in order to reduce the costs for the road section Bucharest Ploiesti that have been calculated for the First Alternative, called The Hipodrom Alternative, by eliminating  the series of art works within the area of Km 60 Km 64.

I.          Location details

The routing will run on the left side of the routing designed for the first Alternative, far from it at distances between 100 m (within the beginning and ending area of the road section) and 2000 m (in the area of Barcanesti approx. Km 60).

The second alternative provides a general orientation towards the west. The routing starts in the northern part of Rafov and crosses the Rafoveanca forest for almost 800 m. after almost 700 m the motorway crosses the Ghighiu brook and then DJ 101D. Further on, the routing passes over agricultural lands, where it crosses several exploitation roads and then the Barcanesti brook.

At Km 59+700 the motorway crosses DN1, where one has designed the arrangement of a road junction. Within this area, it will be necessary to tear down 9 private households as well s the Mayoralty from Barcanesti.

Further on, the routing has a general orientation towards north-west. The obstacles that it meets and crosses by means of a bridge and of an overpass are as follows: a sewer, DN 1 and the rail road Bucharest Brasov, these last two being crossed by means of a common 1200 m long overpass. Then the motorway routing runs in parallel with the DN 1 up to Km 65, where it goes back to the routing on the first Alternative.

The length of the second Alternative routing up to the connection with DN1 (the Vest Ploiesti By-Pass) measures 61,2 Km.

After having analyzed the two motorway routing alternatives suggested by SEARCH CORPORATION, the beneficiary of the works, the National Road Administration, has chosen the second Alternative. This alternative has been favored mainly for its enhanced economic profitability and for the smaller investment costs.

II.       The impact on the environment differences as compared to the first Alternative

II.1. The impact on the natural environment

From the point of view of the impact on the natural environment, the main difference between the two alternatives that have been studied consists of the forest surface that is to be cut down for the purpose of the motorway construction. While the first Alternative crosses only n angle of the Rafoveanca forest, on a distance of almost 300 m, the routing that has been taken into account for the second Alternative crosses the forest through its middle, on a distance of approx. 800 m. In this case, it will be necessary to set up 1,80 m high fencing areas ob both sides of the motorway.

According to the recommendations of the Ploiesti Forestry, there are no protected areas within the territory of the Rafoveanca forest.

II.2. The impact on the human environment

A major negative aspect is represented by the fact that the construction of the second Alternative will lead to the pulling down of almost 9 dwelling places located on both sides of DN 1and of the Mayoralty  from Barcanesti. The solution has been adopted after having consulted the local authorities and the population. In reparation, one has decided to include within the project's rate the building costs for standard houses, as well as the construction of the Mayor's office, on a land that has been offered by the local authorities. The approval of the Mayoralty in Barcanesti with respect to this solution has been submitted in writing.

In the area of the locality of Barcanesti, where the motorway routing crosses DN 1, one has designed 2,0 m high anti-noise panels.