SCAIL - Agriculture 
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NOTICES

October 20th 2025: SCAIL's behaviour in conservative mode is altered when using coordinates under the fields "Installation Name" and "Source Name". Please do not use coordinates there, always use plain English names in these fields.

September 9th 2025: SCAIL background pollution maps for Ireland have been updated to the the year 2021 in line with current APIS (see announcement).

August 1st, 2025: Important Notice Regarding Meteorological Station Data A meteorological station that was used to test the develpment version has made its way to the live version. We are sorry this happened, and we know this will affect some of the runs already performed in this area. SCAIL runs that used the meterologial station 'BENT' (in Shropshire) need to be re-run, as concentration and deposition estimates were underestimated. This only affects a very small area of England and Wales.

If a run used the BENT station your .INP file will mention "BENT.SFC" or "BENT.PFL" on the lines following "ME STARTING". Please re-run your input file and the correct met station will be picked up.

We sincerely apologize for the inconvenience this has caused. We are currently working on an improved version of SCAIL that will significantly enhance user experience.

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18th December 2024 SCAIL Agriculture now uses new emision factors and new housing types for both Pig and Poultry for the UK only (Ireland unaffected). Cattle emission factors are also unaffected. You will not be able to load or run an old input file and will have to select the new options and then save your inputs. The published emission factors are available on the following page Ammonia emission factors for pig and poultry screening, modelling and reporting

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June 11th, 2024: SCAIL background pollution maps for the UK have been updated to the the years 2020-2022 in line with current APIS (see announcement). We have also introduced a new Hybrid mode for users (see User Guide for details of how to use it).

Simple Calculation of Atmospheric Impact Limits from Agricultural Sources (SCAIL-Agriculture) is a screening tool for assessing the impact from pig and poultry farms on human health and on semi-natural areas like SSSIs and SACs. The model provides an estimate of the amount of acidity and nitrogen deposited from a farm as well as predictions of air concentrations of odour and PM10. These values can then be used to assess whether impact limits for human heath or habitats are exceeded or not.

Information regarding the use of SCAIL-Agriculture as a screening tool and instructions for completing the assessment form are provided in the SCAIL-Agriculture User Guide. The User Guide also contains background information on regulatory requirements for the use of SCAIL-Agriculture, including instances where further detailed modelling of emissions will be required. The relevant regulatory authority should be consulted for guidance regarding assessment requirements for planning and permitting purposes.

info Allows the user to reload previously saved input files. [close]
Project Details
Project Notes  
info Use the Project Notes box to enter extra information about the project, source or receptor. For example, add a project name and run details, SSSI site name, habitat structure, or topography etc.[close]
Project Run Mode  
info The project run mode allows the user to specify whether to use 1. "Hybrid mode" which calculates concentrations either side of the receptor location for x4 10 degree sectors (see User Guide for details) or 2. In "Conservative mode" the habitat site is rotated so that it is in the prevailing wind direction for the meteorological file being used. 3. The "Realistic mode" calculates the actual position of the habitat site and should only be used for interest and not as the only run mode for an application. The "Conservative & Hybrid modes" can help to ensure that the effects of local wind fields are captured, however the method works best for situations where there are either single stacks or stacks are closely grouped and care needs to be taken when dealing with stacks that are widely spaced apart. \n\nIf in doubt run the model for both "Conservative mode" and "Hybrid mode" and use the higher of the results. Where SCAIL-Combustion is to be used for regulatory screening purposes, results produced using either the "Hybrid mode" or "Conservative mode" must be reported. Please consult the user guide and technical report for further information including the use of SCAIL for modelling multiple installations or dispersed sources. [close]
  Hybrid Met  Conservative Met  Realistic Met
Location Details
Select Country  
info Select the Country where the habitat is located. [close]
Installation Details
Installation  
info Use INSTALLATIONS to group your sources, the first installation is used as the datum point for the Habitat Lookup and for Conservative Met so makes sure that this reflects the location of most significant emissions. Please note that all sources within an installation will be summed in the output page so if you want to know the specific contribution from a single source (or a group of sources) you should run them as separate installations. The use of SCAIL-Agriculture is not suitable for regulatory screening of sites with multiple installations or dispersed sources, and the relevant Regulatory Authority should be contacted for advice. [close]
Installation Name  
info Provide a name or description of your installation or group of sources. [close]
Installation Location  
info Provide the location of your installation in National Grid or Land Ranger (Great Britain only) format. [close]
Landranger x,y
 
info Provides a link to GoogleMaps to check the location. [close]
Source Details
Source  
info More than one source may be added by selecting 'Add Source'. Sources include animal HOUSING, LITTER/ MANURE STORAGE and LANDSPREADING Sources can be removed from the analysis using the delete button. The use of SCAIL-Agriculture is not suitable for regulatory screening of sites with multiple installations or dispersed sources, and the relevant Regulatory Authority should be contacted for advice. [close]
 Delete
Source  
info Select whether your source relates to Pig, Poultry, Cattle production or you are adding your own emissions - 'User defined emissions'. [close]
Pig Poultry Cattle User defined emissions
New or Existing Source  
info If your application is for a new installation or source, select 'New'. If you are including an existing source and it has been operational for a number of years, select 'Existing'. [close]
Source Name  
info Provide identification for your source.
Source Location  
info Put in the grid reference of the location of the source. You can enter either Landranger (e.g. NJ692258) ore OS x,y co-ordinates (e.g. 369250,825850) in metres. For Northern Ireland or the Republic of Ireland only x,y co-ordinates (e.g. 145665,156755) in metres can be used. [close]
Provides a link to GoogleMaps to check the location.
Landranger x,y
info
Source Type 
infoSelect whether your source is HOUSING, LITTER/ MANURE STORAGE and LANDSPREADING further options are provided for each type to enable emissions to be modelled. [close]

Designated Site details:
Search Radius 
info Enter the radius that you wish to search for habiats sites around your installation. Please note that this search is centred on installation number 1. [close]
  km  
info Use this button to query the database of habitats included in SCAIL-Agriculture. Please note that RAMSAR sites are not included and should be added manually. [close]
No. of Designated Sites 
info This displays the number of habitat sites that were found within the specified radius of installation number 1. The value cannot be edited. [close]
0 found
  
info Use this button to view receptors (shown in blue) and the location of Installation No. 1 (shown in red) in GoogleMaps. If receptors do not display then click on Run Receptor Search to re-run the query of the database. [close]
User specified site Delete
Site Name
Site Location
Landranger x,y
 
info Provides a link to GoogleMaps to check the location. [close]
Habitat within site  
info Use this button to query the database of background ammonia concentrations, nitrogen deposition and acid deposition that are used in the assessment. [close]
 
Human Health Receptor Details
Receptor Delete PM10 percentile    
info Select the statistic for evaluating PM10 concentrations, this can be the Average, 90th Percentile - 90 or 98th Percentile - 98. For most applications 90 should be selected although for Scotland 98 should also be considered. [close]
Receptor Name
Receptor Location
Landranger x,y
 
info Provides a link to GoogleMaps to check the location. [close]
 
info Use this button to query the database of background PM10 concentrations that are used in the assessment. [close]