Glossary 

LAKE ASPHALT:
A naturally occurring mixture of bitumen and finely divided mineral matter which is found in well-defined surface deposits.
    
LAYING:
The process of spreading coated material either with a machine or by hand with the use of rakes and shovels.
    
LEACHATE:
Water and other soluble materials that have drained out of a deposit or tipped material.
     
LIGHTWEIGHT AGGREGATE:
A specialist material, produced from pulverised fuel ash and used where the weight of the aggregate needs to be kept to a minimum (normally form concrete production).
   
LIGNITE:
Brown or black material like coal but sometimes woody in nature.
  
LIMESTONE:
A sedimentary rock, consisting predominantly of calcium carbonate.
   
LIME:
In the industry this term is used for either hydrated lime or ground limestone used as a fertiliser.
    
LOCAL MINERAL PLAN:
County Council schemes for the areas allocated for the extraction of minerals.