It includes some of the following: 

• Type IL Cement aka Portland Limestone Cement (PLC): Common in Western Washington in concrete mixes, it is also seeing adaptation nationwide. It differs from Type I/II because it has 5-15% reduction in cement and adds Limestone instead. It is accepted for certain ASCTM and ACI standards.  

• There are many types of Portland Cement as well as Blended Hydraulic Cements but Type IL is seeing the widest adoption among owners and government agencies.  

• SCMs: Supplementary Cementitious Materials are additives that replace cement and therefore lower the embodied carbon of a concrete mix. They can be added to the cement or later at the batch plant.  

• It is common to see fly ash and slag added to mixes to decrease cement usage. 

• Recycled Water: This includes water used to clean trucks as well as runoff water from the plants. This water is collected and if it reaches criteria specified in ASTM and the mix design, may be used in the mix.  

• Recycled Aggregate: New construction may require redeveloping areas already filled with concrete, asphalt, and masonry. These existing materials can be recycled and turned back into aggregate for certain applications as well as additives to concrete in some cases.