Septic Tank Quad System

From the 'burbs of Cleveland, July 2015: 

This is what a septic system looks like on a two acre parcel. I will protect the owner of the property by calling him Mr. X. He very generously gave me a septic tank tour and it was quite different from anything that I had seen before. I suspect out in the 'burbs, on a large chunk of land, you will find different systems from what we, in tiny-lotville, could possibly have. (You may click on any of these images to enlarge them.)

Pictured above are three of the four chambers of this system. The contents flow from the first through fourth chambers, the water becoming progressively cleaner as it advances. I am standing on the first, underground tank, to take this photograph. Pictured below is the unseen underground first chamber which receives the output from the house: sinks, tubs/showers, laundry, toilets.

The lid to the second chamber, above and below.

Mr. X kindly lifter the concrete lid to the second, visible chamber. 
No noxious aromas wafted forth.

Pictured below is the concrete lid to the third chamber.

Mr. X lifted the lid to the third chamber. Again, no fumes.

Below is the concrete lid to the fourth and final chamber.

Below, the lid opened, reveals some sort of attached mechanism. I forgot to ask what it was. A pump perhaps? This final phase water drains out into piping in the woods. Whatever nitrates or other components are left are sucked up by the vegetation to which the water flows.

Below, you are looking back at the one invisible and three visible tank lids. The forest is maybe another 20 feet behind me where the water eventually goes.

The forest into which the reclaimed water is received. It was pretty darn green I'll have to say; but then it actually rains in the Cleveland 'burbs—a lot this past year.

For fun and refreshment, please don't take this as a depressing tease to the parched Californians, what you see is the lake in the front yard, stocked with bass of some sort. Just enjoy a sight that we are longing to see. We could move to the Cleveland 'burbs to escape the drought if we really wanted to.....and have a nice two-acre parcel with a small lake and lots of fluffy, green trees, that you actually don't need to water.....

Thanks to Mr. X for the septic system tour!