CPP’S No-Rock ™
Fabric Wrapped Septic Pipe
CPP’S No-Rock™ Septic-Leachate drainpipe systems have been used successfully since 1985 in soils that conventional 4” drainpipes with gravel are allowed in on a day to day basis.
The elimination of rock by CPP No-Rock™ Septic Pipes is an advantage in areas where: (1) good rock without “trash fines” is no longer available for a reasonable price, and in (2) hilly, mountainous areas where rolling topography can conspire to create odd shaped building lots that necessitate severe site preparation overgrading in order to be able to lay out a conventional 4” with gravel system. The elimination of overgrading saves trees in the sewer leachate area as well as retains the higher horizon soil profiles that treat septic sewage better than the deeper compacted soils that treat the sewage of overgraded lots.
CPP No-Rock™ Septic Pipe systems have been used in the clay soil areas of North Carolina, West Virginia, Georgia, Kentucky, Tennessee and Alabama. Septic inspectors have always complained that it is troublesome to check the amount of Rock under a 4”-6” pipe. However, the increase in “trash fines” has now lead inspectors to also question gravel quality. With CPP No-Rock systems, inspections are made easier because 12-o’clock locator lines on pipe that show the correct position of drain holes, and the level position of the pipe are the main points that must be inspected.
Large diameter CPP Gravelless septic tank trench systems use a filter wrap that allows for the installation of septic treatment pipes without gravel. The advantage in using CPP No-Rock is evident in areas where there is a shortage of inexpensive quality rock or where the shape and topography of a lot hinder the access of heavy construction equipment. Less equipment use means trees can be saved, less lot grading is needed, and thus fuel and labor are saved.
ASTM-F-481 septic installation specification should be reviewed prior to installation. Some states allow Gravelless large diameter systems to be substituted for conventional systems in Any Soil Type deemed acceptable for a conventional system. Others do not. One should check with local septic inspectors for locally approved soils. Iron Ocre proned organic soils and fine silt soils are examples of unsuitable soil types for fabric wrapped pipes.
CPP’S No-Rock™ septic systems maybe substituted for any conventional 4” pipe gravel trench system utilizing distribution devices, serial distribution, hillside or stepdowns. However, it should not be substituted for bed systems or installed in fill material. It should also be limited to domestic sewage, and not used where there will be large amounts of grease or oil such as in restaurants unless designed by an engineer.
The 8” size pipe will equal to 2-foot wide conventional trench; and the 10” size will equal a 2.5-foot wide trench. To determine the required linear footage of either pipe size, first determine the square footage by dividing the design sewage flow by the appropriate soil’s long term application rate. Then divide this total square footage area figure by either 2 feet (for 8”) or 2.5 feet (for 10”) to establish the linear footage amount. Per chart below, on center (oc) spacing is determined by actual trench width.
Example:
A 3-bedroom house on a loam soil
0.6 gpd/ft 2 = loam soil’s long term application rate.
3BR x 120 gpd = =360 gpd
360 gpd ¸ 0.6 gpd/ft 2 = 600 ft.
600 ft 2 ¸ 2 ft = 300 linear ft of 8” or
600 ft 2 ¸ 2 ft = 240 linear ft of 10”
Suggested Installation of Standards
Nitrification trench bottom minimum width for 8” ………………………… 18”*
Nitrification trench bottom minimum width for 10” ………………………… 24”*
Nitrification line center spacing on 8” ……………………………………. 5” oc*
Nitrification line center spacing on 10” …………………………………… 6.0’ oc*
Nitrification trench bottom minimum depth ………………………………. 18”
Nitrification trench bottom minimum depth (24” preferred) …………………36”
Nitrification trench bottom slope ………………………… level to 1” per 100 ft
Nitrification line minimum cover ………………………………………… 6”
Nitrification line maximum cover (12” preferred) ………………………….. 24”
Nitrification line maximum length ……………………………………….. 100’
*Based on Minimum Trench Width Bottom Noted Above /w 5 Foot OC Minimum
The corrugated pipe used shall comply with ASTM-667. Also the installer should be careful to note that the filter wrap is light sensitive, and should not be exposed to sunlight for extended periods of time. The installer should also take care during installation to avoid tearing of the filter material. The protective plastic wrap that protects the filter should be disposed of offsite.
Say No to Rock with CPP’S No-Rock™
 |
Size |
Part # |
Package Description |
8” |
0830020B |
CPP’S No-Rock TM Septic 20 ft. with filter wrap |
|
|
 |
|
