Charles County, Maryland Perc Test Information and Requirements

Perc Tests In Charles County, Maryland

• The perc test is performed by digging at least three holes. One of these holes is a water table test and the other two are the actual perc tests.
• good perc soils are found very shallow in some areas, while in other areas, they can be very deep.
• A backhoe drill machine is used most of the time, because many of the tests are deep tests.  If a backhoe is used, a machine that can drill down at least 18 feet is recommended.

You can obtain additional information from the Environmental Health Office at 301-609-6751.  An application can be obtained from the Charles County Health Department, Environmental Health Department, Environmental Health Services.  The application should be completed and returned with the applicable fee and a site plan of the property.  The site plan should show land boundaries and the approximate location of the proposed house, perc location, driveway, and existing wells or septic systems that are within 100 feet of the property line.  The Department will accept hand-drawn site plans for testing five or fewer lots, but plans for subdivisions of six or more lots must be prepared by a Maryland registered engineer or land surveyor.

The Charles County Requirements
for a Satisfactory Perc Test

For a perc test to be considered satisfactory in Charles County, the soils must demonstrate the following abilities:

1. Function Hydraulically (i.e., Percolate):  According to Maryland Regulations for Charles County, soil that will percolate water at a rate of less than 30 minutes per inch in a one cubic foot hole is uncommon in Charles County.  This is because the actual test depth is often over five feet deep.  This prohibits using a shovel to dig the hole, per OSHA rules.  When a round auger test hole is used, it should be not greater than 16 inches.  This exposes approximately the same side wall area as a cubic foot hole. If the round test hole is smaller than 16 inches (auger holes are commonly 8 to 10 inches), the following conversion factor will be used on the percolation rate.

2. Provide Adequate Treatment:  This refers back to the need for a water table test to ensure that there is no contamination of the ground water.

3. Soil Consistency:  The purpose of performing more than one perc test is to determine that there is soil consistency in a large enough area to support a septic system.  A minimum of 10,000 square feet may be necessary if soil and land conditions require it.