Gone that era when we only had small sumps and we used to dump the ugly bad smelling metalworking fluid every now and then in the field out back, or along the nearby dirt road.  This was common practice as recently as the 1960's, even in California.  With rising production costs, increases environmental awareness and regulation, technological advances in Metalworking fluid formulations followed.  Today we have fluids which can last more than a year if expertly maintained.  With the best centralized tank designs, some fluid manufacturers are contemplating multiple years of life (BLASER).

Key to longer drain intervals is an effective filtration system.  Mayfran International is one of elite designers of the super systems for the large centralized metalworking fluid systems. They design and build complete tailor-made filtration plants for coolant and chip handling, supporting flow rates of up to 40,000 l/min (10,500 gpm). Various filtration options for stand-alone sumps are also available.