bs sponge private limited - India Environment Portal

B.S. SPONGE PRIVATE LIMITED
Village: Taraimal, Tehsil: Gharghoda, District: Raigarh, (C.G.)
REIA Report for the Proposed Mini Integrated Steel Plant
Chapter – 4
hemispherical sound wave propagation through homogeneous loss free medium, one can
estimate noise levels at various locations, due to different sources using model based on
first principle, as per the following equation:
Lp2 = Lp1 – 20 Log (r2/r1) - Ael.2
Where Lp1 and Lp2 are sound pressure levels at points located at distance r1 and r2 from
the source and Ae1.2 is the excess attenuation due to environmental conditions. Combined
affect of all the sources then can be determined at various locations by logarithmic
addition.
It is first approximation one can assume that for all general population in the villages, every
noise source in the plane is a point source. The average equivalent sound power level of
such a point source can be estimated for different distances and directions from
hypothetical source by applying following equation:
Lp = Lw - 20 Log r – Ae – 8
Where Lw is the sound power level of the source, Lp is sound pressure level at a distance r
and Ae is environmental attenuation factor. A combined noise level Lp (total) of all the
sources at a particular place is given by:
Lp(total) = 10 Log (10 Lp1/10) + 10 (Lp2/10) + ---------)
Major noise generating sources were identified from the proposed activity for prediction
purposes. The major noise generating sources are STG, DG set & compressors. The
predictions have been made to represent the worst case. The noise levels at various
distances were calculated using wave divergence model.
The model was run for ascertaining the areas where we could get the noise levels of 35,
45, 50,55,60,65, and considering the other noise generating sources from the plant.
Silencers will be provided to the DG Sets. All machinery will be manufactured keeping in
view of the MOEF/OSHA standards on Noise levels. The Ambient Noise levels will be
within the standards prescribed by MOE&F, GOI vide Notification dated 14-02-2000 under
the Noise pollution (regulation & control) Rules, 2000.
4.3.2. PREDICTION OF IMPACTS ON COMMUNITY
Day and Night sound pressure levels, Ldn is often used to describe the community noise
exposure which include 10 dBA night time penalty. As the nearest human settlement is
about 2.5 Km. from the plant, the impact of noise on general population would be
insignificant.
PIONEER ENVIRO 4 - 13 Environmental Impact Assessment Report
Laboratories & Consultants Pvt. Ltd.