Concerns have been raised by a resident at [redacted] South Street, Lochgelly regarding suspected environmental noise from the Mossmorran Complex which consists of ExxonMobil Fife Ethylene Plant (FEP) and Shell Fife Natural Gas Liquids (FNGL), Cowdenbeath. In response to these concerns SEPA South Field Chemistry completed an assessment of the indoor noise.
A domestic noise monitoring system (Bruel and Kjaer Matron) was deployed to monitor indoor noise over a 21 day period (15/08/2014 to 05/09/2014).
Both FEP and FNGL, Mossmorran currently hold Pollution Prevention and Control Permits (PPC/A/1013494 – Part A and PPC/A/1013495 Part A respectively) and operate continuously throughout the year.
Table: Daytime (07:00 > 23:00)
|Date||Daytime 16hr Laeq (dB)|
Nineteen out of the twenty two daytime 16-hour Laeq measurements shown in the table exceeded the WHO daytime guideline value of 35dB(A)
Table: Night-time (23:00 > 7:00) 8hr Laeq
|Date||Night-time 8hr Laeq (dB)|
|15 > 16/08/2014||27.4|
|16 > 17/08/2014||45.7|
|17 > 18/08/2014||24.7|
|18 > 19/08/2014||25.5|
|119 > 20/08/2014||37.3|
|20 > 21/08/2014||28.4|
|21 > 22/08/2014||24.5|
|22 > 23/08/2014||34.3|
|23 > 24/08/2014||34.6|
|24 > 25/08/2014||35.2|
|25 > 26/08/2014||36.9|
|26 > 27/08/2014||32.6|
|27 > 28/08/2014||34.8|
|28 > 29/08/2014||37.6|
|29 > 30/08/2014||35.9|
|31/08 > 01/09/2014||23.9|
|01 > 02/09/2014||27.7|
|02 > 03/09/2014||26.4|
|03 > 04/09/2014||25.7|
|04 > 05/09/2014||32.1|
Eleven out of twenty one night-time 8-hour Laeq measurements shown in the Table exceeded the WHO night-time value of 30dB(A).
Tonal Noise Associated with Recordings
Noise can be described as tonal if it contains noticeable or discreet continuous note. This includes noises such as hums, hisses, screeches, drones, etc. The presence of tonal noise can give rise to complaints.
Tonal noise is generally more noticeable and more annoying than non-tonal noise of the same level; this is however, subjective in nature.
A tonal frequency is defined as a third octave frequency band that exceeds the adjacent two, third octave bands by more than 5dB.
The tones associated with each sound recording are outline in the table below.
|SEPA Sound Recording ID||Tones Identified (Hz)||SEPA Sound Recording ID||Tones Identified (Hz)|
|SREC10||160, 10k||SREC25||50, 10k|
The daytime (07:00 to 23:00) and night-time (23:00 to 07:00) MATRON measurements were compared against the World Health Organisation Guidelines for Community Noise. The WHO Guidelines for Community Noise assume that the noise is continous and steady over the 16-hour daytime or 8-hour night0time period. This comparison showed nineteen out of the twenty two daytime measurements and eleven out of the twenty one night-time measurements exceeded the WHO Guidelines for Community Noise. However, the unattended measurements taken by the MATRON should be taken with caution as the MATRON measures all noise (including traffic, talking, etc.) and not just that specific to the Mossmorran complex. Without undertaking attended measurements it is difficult to determine the contribution of the specific noise from the Mossmorran complex to the overall noise level.
When comparing the recordings against DEFRA’s criterion curve for the assessment of low frequency noise, there were several breaches noted, the source of the noise causing these breaches is not currently known.
Additional external noise monitoring should be undertaken (by SEPA) to determine the source of the problem noise at South Street, Lochgelly. At present, it is not clear the source of the low frequency noise breaches and the noise that the complainant is concern with.
Existing noise data reports / maps from the surrounding area including the Little Raith wind farm should be consulted (by SEPA) to gain a clear understanding of the noise sources, levels, tones and frequencies in this area.
View Full Report: 141105-final-noise-report_redacted (PDF)