Radon treatment system and method

The system for removing the soil gas from the ground surrounding the building structure, includes a clean-out pipe, an air duct system, and a fan. The clean-out pipes are installed inside the building structure, accessible from the ground level and near junctions between the interconnecting pipes and the drain tile. The air duct system is securable to a clean-out pipe, and the fan is installed inside the air duct system. The air duct system is disconnected from the clean-out pipe during the cleaning of the drain tile system. The pressurized fluid projecting through the tip of the rocket nozzle, removes any obstructions in the drain tile, and the pressurized fluid projecting rearward from the nozzle, propels the rocket nozzle through the drain tile system. The air duct system is then connected to the clean-out pipe. The venting of air away from the drain tile system creates a negative pressure, which draws the soil gas into the porous drain tile. By continuously operating the fan, venting the air in the drain tile the soil gas is effectively prevented from entering the building structure.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a new system and method for removing soil 
gas from in a safe and effective manner from the ground surrounding a 
building structure. 
2. Background Art 
Radon is an invisible, odorless, tasteless radioactive gas produced by the 
natural decay of uranium in the soil. The Center for Disease Control in 
Atlanta, Georgia has reported that human exposure to radon gas is the 
primary cause of lung cancer, except for cigarettes. Such human exposure 
routinely occurs from radon gas that seeps from the ground into dwellings 
and other building structures. Scientists estimate that 20,000 Americans 
die annually as a result of radon exposure. 
In a recent study completed by the Environmental Protection Agency (1988) 
in a seven state area, it was found that one home in three had dangerous 
levels of radon gas. The EPA has set a recommended level for remedial 
action at 4 picocuries per liter, which is equivalent to 200 chest x-rays 
per year. Even at this level studies have indicated that almost 5 people 
out of 100 exposed to high levels of radon will die of radon-induced lung 
cancer. 
Conventional dwellings and other building structures are typically built 
upon foundation walls which define the basement area. The foundation walls 
and the footers are in direct contact with the ground surrounding the 
building structure. Most such building structures have an existing drain 
tile system in the immediate proximity of the foundation, which enables 
water and debris immediately surrounding the building structure to drain 
away therefrom. The drain tile system is generally located within a bed of 
water-permable material such as gravel, the gravel bed surrounding the 
building structure. 
The drain tile system is generally located around the perimeter of the 
building structure slightly below the foundation, either directly under 
the perimeter of the building structure or surrounding the perimeter of 
the building structure. The drain tile system is made of a water porous 
tile and is laid in a continuous channel, so that water and contaminants 
disposed in the vicinity of the building structure can be routed across 
and through the drain tile system and into a sewer or a sump pump. The 
drain tile system is generally in fluid communication with a series of 
interconnecting pipes disposed underneath the building structure. 
Generally, these interconnecting pipes have gradual bends in the direction 
of fluid flow and are accessible through several floor drains located in 
the basement floor of the building structure. The drain tile system feeds 
into either a sump pump or a centralized sewer. 
Soil ventilation draws soil gas away from the building structure. The 
suction of soil gas through the drain tile system is enhanced by a fan 
which suctions the soil gas from the soil around the foundation and 
through the drain tile system and away from the building structure, 
effectively preventing the soil gas from entering the building structure. 
Drain tile suction is an inexpensive and nonobtrusive method of active 
soil ventilation, and such systems have demonstrated reductions in radon 
gas as high as 99%. 
For drain tile suction to be effective, it is critical that the drain tile 
system must be maintained free from objects which tend to block the normal 
flow of water therethrough and prevent ventilation of the drain tile 
system. 
Oftentimes, the drain tile system is interconnected to the eaves wherein 
leaves and twigs, roof tar, and even the remains of small animals may 
become lodged therein. Since the flow of water and debris through the 
drain tile is at most a trickle, the drain tile is never flushed. When the 
drain tile becomes blocked at various locations with debris, as frequently 
occurs, the drain tile system is extremely difficult to clean. The 
property owner is confronted with choosing between: 
(a) digging several feet deep into all the land surrounding the building 
structure to access the existing drain tile system, and to locate and 
remove the blockages; or 
(b) inserting a second drain tile system underneath the building structure, 
and thereby jackhammering major portions of the existing basement floor. 
What is needed is a new method and apparatus for cleaning the existing 
drain tile that overcomes the disadvantages already noted; a method and 
system which combines the continuous soil ventilation through the drain 
tile system to remove soil gas from the vicinity of a building structure 
with a new method and system for keeping the drain tile system free from 
blockages. 
SUMMARY OF THE INVENTION 
Thomas Francis and K. Rand Dykman have invented a new method of cleaning 
drain tile systems by using a rocket nozzle attached to a flexible tubing, 
with highly pressurized water (preferably 2200 to 5200 psi) propelling the 
rocket nozzle through the drain tile system, and removing blockages and 
other debris therefrom. This method for cleaning drain tile systems is 
fully disclosed in U.S. patent application Ser. No. 07/182,178, entitled 
"Foundation Drain Cleaning Apparatus and Method", filed on Apr. 15th, 1988 
now U.S. Pat. No. 4,848,380. 
This invention enables blockages and debris to be effectively removed from 
the existing drain tile, while not damaging the landscape around the 
building structure, the basement floor, or the drain tile. This enables 
the hidden drain tile system to be located, and involves the construction 
of an accessing system that can be permanently used as thereafter needed. 
The system accesses the drain tile system at several discrete locations, 
clearing blockages from anywhere in the drain tile system, and cleaning 
the inside surface of the drain tile system so that soil gas can be 
continuously ventilated therethrough. 
The present invention effectively enables soil gas to be removed from the 
ground surrounding a building structure. The system includes a clean-out 
pipe, an air duct system, and a fan. One or more clean-out pipes are 
disposed near the junctions between the interconnecting pipes and the 
drain tile system, the interconnecting pipes being disposed underneath the 
building structure. Preferably, the clean-out pipes are disposed inside 
the building structure, and are accessible from the ground level. The air 
duct system is in fluid communication with the clean-out pipe. The air 
duct system is vented to atmosphere outside the building structure. The 
air duct system is secureable to a clean-out pipe, and the fan is 
installed, preferably inside the air duct system. The fan enables air from 
the drain tile system to be vented through the clean-out pipe, through the 
air duct system, and to atmosphere surrounding the building structure. 
The position of the junctions between the interconnecting pipe and the 
drain tile system are preferably located by inserting a rocket nozzle into 
a centralized drain in the basement floor. The rocket nozzle is propelled 
through the interconnecting pipes, and the nozzle will stop at the 
junction between the interconnecting pipe and the drain tile. The position 
of the rocket nozzle is located through the floor of the basement by the 
sound that the fluid makes as it escapes from the nozzle. The clean-out 
pipes are then inserted into the basement floor by digging through the 
basement floor in the vicinity of the junction. 
The air duct system is preferably disconnected from the clean-out pipe 
during the cleaning of the drain tile system. The pressurized fluid 
projecting through the tip of the rocket nozzle, removes any obstructions 
in the drain tile, and the pressurized fluid projecting rearward from the 
nozzle, propels the rocket nozzle through the drain tile in a forward 
direction and washes the debris through the drain tile system. 
After the debris has been cleaned from the drain tile system, the air duct 
system is reconnected to the system and the fan is energized. A negative 
pressure in the clean drain tile system draws the soil gas surrounding the 
drain tile system into the porous drain tile. By continuously operating 
the fan, the air in the drain tile system is vented through the air duct 
system and to atmosphere above the building structure. Hence, the soil gas 
is effectively prevented from entering the building structure. 
For a more complete understanding of the radon treatment system and method 
of the present invention, reference is made to the following detailed 
description and accompanying drawings in which the presently preferred 
embodiments of the invention are illustrated by way of example. As the 
invention may be embodied in several forms without departing from the 
spirit or essential characteristics thereof, it is expressly understood 
that the drawings are for purposes of illustration and description only, 
and are not intended as a definition of the limits of the invention. 
Throughout the following description and drawings, identical reference 
numbers refer to the same component throughout the several views.

DETAILED DESCRIPTION OF THE INVENTION 
Referring now to the drawings, the system 66 for removing the soil gas from 
the ground surrounding the building structure 12, includes a clean-out 
pipe 64, an air duct system 46, and a fan 60, which are installed in 
conjunction with an existing drain tile system 10 (see FIG. 3). 
The water porous drain tile system 10 will not effectively remove the soil 
gas from the ground surrounding the building structure 12 if: 
(a) there are one or more blockages in the drain tile system 10 which 
prevent a portion of the drain tile system 10 from venting through the 
clean-out pipe 64 and the air duct system 46; or 
(b) debris is allowed to build up along the inside surface of the drain 
tile system 10 preventing the soil gas to be drawn into the drain tile 
system 10 by the negative pressure of the fan 60. 
Accordingly, regular cleaning and maintenance of the complete drain tile 
system 10 is required if the soil gas is to be vented through the drain 
tile system 10. 
The drain tile system 10 may be cleaned and maintained by highly 
pressurized water being projected through a rocket nozzle 32 which is in 
fluid communication with a flexible tubing 30 (see FIG. 1). The head 
portion of the rocket nozzle 32 preferably has an opening on the tip 
thereof through which the pressurized water is dischargeable in the 
forward direction. The tail portion of the rocket nozzle 32 is in fluid 
communication with a high pressure water supply. The rocket nozzle 32 has 
a recess between the head portion and tail portion, the recess having a 
rearward surface. At least two apertures are disposed along the recess. 
The water escaping through the apertures in the recess propel the rocket 
nozzle 32 in a forward direction. 
As shown in FIG. 2, the cleanout pipes 64 are disposed proximate to the 
junctions 24 between the interconnecting pipes 22 and the drain tile 
system 10. Each clean-out pipe 64 is preferably four inch Schedule 40 
pipe, and is in fluid communication with both the drain tile system 10 and 
an interconnecting pipe 22. Preferably, a clean-out pipe 64 is installed 
at each junction between the interconnecting pipe 22 and the drain tile 
system 10, the clean-out pipes 64 being disposed inside the building 
structure 12, and accessible from the ground level. To remove the 
blockages from the drain tile system 10, the rocket nozzle 32 is 
preferably inserted into the drain tile system 10 through the clean-out 
pipes 64. 
The position of each junction 24 must be located before the clean-out pipes 
64 can be installed. One way of locating the junctions 24 is by inserting 
a snake into a floor drain and through the interconnecting pipe. However, 
the junctions 24 are preferably located by inserting the rocket nozzle 32 
into a centralized drain 26 in the basement floor 14. The pressurized 
water propels the rocket nozzle 32 through the interconnecting pipes 22. 
The rocket nozzle 32 will stop at a junction 24, since the rocket nozzle 
32 cannot ordinarily overcome the radical bends that generally exist 
between the interconnecting pipe 22 and the drain tile system 10. The 
position of the rocket nozzle 32 is located through the floor 14 of the 
building structure by the sound that the water escaping from the rocket 
nozzle 32. Once the position of the junctions 24 are located, clean-out 
pipes 64 are installed into the basement floor 14 in the vicinity of each 
junction 24. A hole is made in the floor of the building structure 12 at 
the location for the clean-out pipe 64, and a portion of the 
interconnecting pipe 22 is removed. A clean-out tee 64 is inserted 
therein, and a boot 88 with two stainless steel clamps is placed around 
both ends were the clean-out tee 64 meets the interconnecting pipe 22. The 
stem of the clean-out pipe 64 extends into the floor of the building 
structure 12, and is preferably threaded so that it may be capped when not 
in use. 
The flexible tubing 36 and the tube fittings are capable of withstanding 
the flow of high pressure water. A conventional pump (not shown) is 
connected to the tap water to raise the supply pressure of the water from 
2200 to 5200 psi. Water flows through the rocket nozzle 32 at a rate of 
about 4.5 gallons per minute. A foot pedal control valve 40 is used to 
start and stop the water flow into the tubing 36 and the rocket nozzle 32. 
The control valve 40 has a spring-actuated lever which is actuated by the 
foot of the operator. When water is flowing through the system, actuation 
of the control valve 40 will terminate the water flow to the rocket nozzle 
32. 
As pressurized water is supplied to the rocket nozzle 32, the water is 
projected through the apertures, propelling the rocket nozzle 32 in a 
forward direction through the drain tile system 10. As the rocket nozzle 
32 is propelled through the drain tile system 10, the pressurized water 
flowing through the tip of the rocket nozzle 32 is continually directed at 
the debris with sufficient force to clear blockages in the drain tile 
system 10. The flow of the pressurized water rearwardly through the rocket 
nozzle 32 serves to: (1) propel the rocket nozzle 32 through the drain 
tile system 10; (2) separate the debris from the drain tile system 10; and 
(3) wash the debris through the drain tile system 10 and into either a 
sump pump or a central sewer. 
The air duct system 46 as described herein preferably includes a duct 
segment 44, a primary duct 50, and a boot 48 and two stainless steel 
clamps 49 (see FIG. 3). The air duct system 46 is mounted and attached to 
one of the clean-out pipes 64 as shown in FIG. 3. The duct segment 44 is 
preferably PVC, Schedule 40 piping that is about four inches long. The air 
duct boot 48 and the pipe boots 88 are preferably Fernco rubber couplings. 
By placing the air duct system 46 in fluid communication with the drain 
tile system 10, air from inside the drain tile system 10 can be circulated 
into and through the air duct. The duct segment 44, the boot 48, and the 
clamps 49 can be quickly and readily disconnected from the clean-out pipe 
64, enabling the rocket nozzle 32 to be inserted therein during the 
cleaning and maintaining of the drain tile system 10. The air duct system 
46 is vented to the air outside, and preferably above the building 
structure 12. 
The top end portions of all of the clean-out pipes 64 are preferably 
threaded, so that a pipe cap (not shown) may be inserted therein when the 
drain tile system 10 is not being cleaned. The pipe caps are preferably 
generally flush with the floor of the building structure 12. The clean-out 
pipe 64 that is to be connected to the air duct system 46 is threadably 
engaged with the duct segment 44. The rubber boot 48 is subsequently 
clamped over the top portion of the duct segment 44 and the primary duct 
50, to prevent the soil gas from leaking into the building structure 12, 
during the continuously venting of the drain tile system 10. When the 
drain tile system 10 is to be periodically flushed and cleaned by means of 
the rocket nozzle/high pressure water, the clamps 49 are removed, the duct 
segment 44 is unthreaded from the clean-out pipe 64, and the rocket nozzle 
32 is inserted into the clean-out pipe 64. 
The fan 60 is disposed above the ground level. The fan 60 is disposed 
proximate to the primary duct 50, and preferably in the primary duct 50 
and near the drain tile system 10 about two feet from the basement floor 
14. The fan 60 enables the soil gas to be drawn into the porous drain tile 
system 10, and to circulate into and through the clean-out pipe 64, and 
the air duct system 46, where it is vented to the atmosphere over the 
building structure 12. 
The cleaning and the flushing of debris from the drain tile system 10 
creates a negative pressure in the drain tile system 10. This negative 
pressure draws the soil gas in the ground surrounding the drain tile 
system 10 to seep into the porous drain tile. By continuously venting the 
air in the drain tile system 10 through the air duct system 46 and to 
atmosphere above the building structure 12, any contaminants in the ground 
air surrounding the drain tile system 10 are effectively removed 
therefrom. 
While the radon treatment method and system have been described in 
conjunction with a specific embodiment, it is evident that many 
alternatives, modifications, and variations will be apparent to those 
skilled in the art in light of the disclosure herein. It is intended that 
the metes and bounds of the invention be determined by the appended claims 
rather than by the language of the above specification, and that all such 
alternatives, modifications, and variations which form a functional or 
conjointly cooperative equivalent are intended to be included within the 
spirit and scope of these claims.