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1 January 21, 2014 File No Mark Antunes, Technical Information Manager E.P. Henry Corporation 16 Anderson Road Parker Ford, PA Reference: Permeable Paver Infiltration Testing Eco Brick Stone Unit Philadelphia Navy Yard Philadelphia, Pennsylvania Dear Mr. Antunes: Introduction This letter summarizes the results of the infiltration testing conducted on E.P. Henry s Eco Brick Stone permeable segmental pavement system at the above referenced site. To facilitate the study, Gilmore & Associates, Inc. (G&A) performed one single-ring infiltration test at the GridSTAR Net Zero Energy Demonstration Project within the Philadelphia Navy Yard on November 25, The purpose of this study was to establish a post-construction infiltration rate for stormwater passing through the Eco Brick pavement surface into open-graded base materials. Setting As part of the GridSTAR project, E.P. Henry s Eco Brick Stone permeable paver walkway was constructed at the Navy Yard in October of The Eco Brick Stone units are 4 inches wide, 8 inches long, and 2 3/8 inches thick. The Eco Brick paver s permeability is a function of the joint system with water infiltration occurring along the perimeter of each individual paver. The paver system was installed on a section of three washed aggregate layers (AASHTO designations provided): 6-inches of No. 2 aggregate followed by 4-inches of No. 57 aggregate followed by a 2- inch bedding layer of No. 8 stone. No. 8 stone was also used to fill the Eco Brick joints. Procedure A single-ring infiltrometer was used to test the surface infiltration rate of the constructed Eco Brick Stone test pads per ASTM C This testing method was developed for determining the field surface infiltration rate of in-place permeable pavement systems with solid interlocking concrete paving units, concrete grid paving units, or clay paving brick. The single-ring infiltrometer consisted of a 0.25-inch gauge, 12-inch diameter, 10-inch high steel cylinder. The ring was placed on the pavement so that a representative infiltration area was exposed at the cylinder base and then sealed to the pavement surface with plumber s putty. Water was added to the single-ring per ASTM C 1781 and the time was recorded when the required amount infiltrated into the pavement system. The surface infiltration testing was performed two times at the test location in accordance with the ASTM standard. The infiltration results for the Eco Brick Stone permeable pavement system are located on the attached summary sheet. 65 E. Butler Avenue Suite 100 New Britain, PA Phone: Fax:

2 Mark S. Antunes, E.P. Henry Corporation Page Permeable Paver Infiltration Testing January 21, 2014 Results An average surface infiltration rate of inches per hour was recorded for the Eco Brick Stone pavement system with No. 8 aggregate joint fill. The surface infiltration rate of the Eco Brick Stone pavement system is significantly faster than what can be expected in most natural environments. This testing supports the use of these segmental pavement systems as a permeable infiltration surface and stormwater conveyance mechanism for green infrastructure projects. For permeable segmental pavements in stormwater management applications, soil infiltration testing is necessary to support the design an appropriate pavement section engineered to control the required storm volume. For stormwater management applications, site specific testing, engineered design details, and a maintenance plan specification are required. G&A appreciates the opportunity to work with you on this project. Please do not hesitate to contact us with any questions. Respectfully submitted, Matthew C. Hostrander, CPSS Soil Scientist Gilmore & Associates, Inc. Trevor G. Woodward, P.G. Senior Project Manager Gilmore & Associates, Inc. MCH/TGW/dmk Enclosures: Eco Brick Stone Pavement Infiltration Test Results Runoff References & Documentation

3 Surface Infiltration Test Results E.P. Henry Eco Brick Stone Permeable Interlocking Pavement Philadelphia Naval Yard G&A Project No January 21, 2014 Eco Brick Stone 4 x8 with No. 8 Aggregate Joint Infill Test Date 11/25/13 Prewetting (8 lbs. of water) 17 seconds* Test 1 (40 lbs. of water) Test 2 (40 lbs. of water) 68 seconds 66 seconds Infiltration Rate per ASTM C 1781 Infiltration Rate per ASTM C in./hr in./hr. Average Infiltration Rate (in./hr.) *If during prewetting 8 pounds (1 gallon) of water infiltrates in less than 30 seconds, the infiltration test shall be conducted with 40 pounds of water. ASTM C 1781 Infiltration Rate Calculation I = (KM) / (D 2 t) Where: I = Infiltration Rate (in./hr.) M = Mass of Infiltrated Water (lbs.) D = Inside Diameter of Infiltration Ring (in.) t = Time Required for Measure Amount of Water to Infiltrate (sec.) K = 4,583,666,000 in SI Units or 126,870 in (inch/pound) units 65 E. Butler Avenue Suite 100 New Britain, PA Phone: Fax:

4 Eco Brick Stone Rational C The methodology used for determination of a Rational C for the Eco Brick Stone system: Using the straight weighted area of pervious vs. impervious for a standard section of the system does not provide an accurate representation of the infiltration capacity of this type of paving. Therefore the infiltration rate from field testing on the Eco Brick Stone system, as summarized in the letter report dated December 3, 2013, was used in conjunction with an NRCS* i graph (attached) which relates Runoff Curve Number (CN) to Infiltration Rate. Per that graph, rates higher than 6.3 inches per hour (CN=35) are not recommended for design purposes and, since the tested rates were significantly higher than this, a Curve Number of 35 was used to provide additional factor of safety for the system The CN value was used with the Rossmiller Equation to calculate the equivalent Rational C for various conditions including Region 4 versus Region 5 rainfall, storm frequency, and slope of the installed pavers. The resultant Rational C had little variability in the respective conditions; therefore the Rational C was simplified to suit a standard table of Rational Runoff Coefficients which is attached. Installed Slope 0-2% 2-6% >6% Storms less than 25-year Storms 25-year and over This calculation is valid for PADOT Region 4 and Region 5 rainfall conditions only. i *NRCS USDA Natural Resource Conservation Service 65 E. Butler Avenue Suite 100 New Britain, PA Phone: Fax:

5 Rational Runoff Coefficients Storms less than 25-year Soil Type A Soil Type B Soil Type C Soil Type D Land Use 0-2% 2-6% 6% + 0-2% 2-6% 6% + 0-2% 2-6% 6% + 0-2% 2-6% 6% + Cultivated Land Pasture Meadow Forest Open space, lawns Parking, impervious EP Henry Eco Brick Stone Storms 25-year & over Soil Type A Soil Type B Soil Type C Soil Type D Land Use 0-2% 2-6% 6% + 0-2% 2-6% 6% + 0-2% 2-6% 6% + 0-2% 2-6% 6% + Cultivated Land Pasture Meadow Forest Open space, lawns Parking, impervious EP Henry Eco Brick Stone

6 Rational Runoff Coefficients Storms less than 25-year Soil Type A Soil Type B Soil Type C Soil Type D Land Use 0-2% 2-6% 6% + 0-2% 2-6% 6% + 0-2% 2-6% 6% + 0-2% 2-6% 6% + Residential 1/8 acre lots /4 acre lots /3 acre lots /2 acre lots acre lots Industrial Commercial Streets Storms 25-year & over Soil Type A Soil Type B Soil Type C Soil Type D Land Use 0-2% 2-6% 6% + 0-2% 2-6% 6% + 0-2% 2-6% 6% + 0-2% 2-6% 6% + Residential 1/8 acre lots /4 acre lots /3 acre lots /2 acre lots acre lots Industrial Commercial Streets

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