Lead is a type of non- point source contamination

A letter writte By Laren to a dealer:

Hello                 ,

Please archive this as a lead resource.

I would like to help you develop your water theory as it pertains to what you believe to be a honest and true statement of facts. 
This is my researched and experienced opinion on lead.
Lead is a big deal to a lot of people, and it should be. Managing expectations of your systems are one of the biggest and most important aspects of the sales process. 
I know I’ve said this many times but it’s important, if you don’t give the customer the expectations of what your system will do and won’t do then they’ll make up their own definition of success and failure. This  sequences into service calls and phone calls that can be avoided. Unhappy customers and bad reviews. Lead most likely comes from inside the home plumbing. Lead can also come from the meter to the house because nobody can decide who owns that. But if you see lead on the water quality report and your system is designed to take it out, the customer will expect it to be off the water report. But how is your system that’s on the point of entry supposed to remove lead that is coming from a bathroom faucet upstairs?Non-point source contamination refers to pollution that doesn't come from a single, identifiable source, but rather from multiple sources spread out over a larger area. In the context of lead contamination in your home, I use non-point sources to include lead leaching from various plumbing fixtures, pipes, or solder used throughout a homes plumbing system.
Since lead can come from different locations, it can be challenging to pinpoint exactly where it's coming from. Lead in your home water most likely comes from lead-containing plumbing materials like pipes, faucets, and fixtures, particularly if your home was built before 1986 when lead solder was commonly used in plumbing systems; this is especially concerning when water sits in the pipes for a period of time, allowing lead to leach into the water through corrosion. Key points about lead in water: 

• Older homes: The biggest risk factor for lead in water is living in an older house with older plumbing. 
• Lead pipes: Lead service lines (pipes connecting the water main to your home) and internal plumbing pipes can be made of lead. 
• Lead solder: Solder used to join pipes in older plumbing systems may contain lead. 
• Faucets and fixtures: Lead can also be present in older faucets and fixture components. 
• 1.Water Testing: Test water from different faucets to identify which ones have higher lead levels.2. Inspect Plumbing:Check for any lead pipes or fixtures in your plumbing system.3. Use Filters:Consider using water filters  to remove lead for drinking and cooking water.