September 9, 2009 Corzo Castella Carballo Thompson Salman, P.A. 90 Ponce de Leon Boulevard Suite 900 Coral Gables, Florida 3334 Attn: Mr. Ian John, E.I. Re: Exfiltration Test Results Glenroyal East Phase Roadway and Drainage Improvements NW 7 th Avenue and NW 7 th Street Miami, Miami-Dade County, Florida Terracon Job No. 3409509 Dear Mr. John: As proposed we have completed 9 exfiltration tests for the above referenced project. The following is a brief description of the test procedures and an overview of the results. Also included in the attachments are Exfiltration Sheets containing the test data and an Exfiltration Test Location Diagram showing the approximate location of the tests. Nine exfiltration tests (E- through E-9) were performed at the site in general accordance with the South Florida Water Management District (SFWMD) procedures for the "Usual Open-Hole Constant Head Condition" Percolation Tests. The test was performed in a 0- inch diameter borehole advanced by means of a PVC casing to a depth of 5 feet below the existing ground surface. A 6-inch diameter perforated PVC pipe was placed in the borehole prior to retrieving the casing. Water was then pumped into the borehole in order to raise the water level in the borehole to near the ground surface. Once the inflow stabilized with the outflow rate, the average pumping rate and the elevation of the water obtained with this stabilized flow rate were recorded. Material encountered at the exfiltration test site was identified in the field from cuttings brought to the surface by the augering process. Upon completion of the drilling and following groundwater stabilization, the distance from the existing ground surface to the water table was recorded. The rate of water flow required to maintain a constant hydraulic head was then recorded. The hydraulic conductivity value was determined from the test results and is presented in the Exfiltration Test Sheets attachment in this memo. The hydraulic conductivity value is reported in units of cubic feet per second per square foot of seepage area per foot of head (cfs/ft 2 -ft head). Terracon Consultants, Inc. 0080 NW 53 rd Street Sunrise, FL 3335 P [954] 74 8282 F [954] 74 8240 terracon.com
Glenroyal East Phase Drainage and Roadway Improvements Terracon Job No. 3409509 September 9, 2009 The soil profile at the exfiltration test locations generally consisted of fill material consisting of sand and limerock to depths of approximately 2 to feet below grade. Sand with limestone fragments was encountered below the fill material to a depth of approximately 3 feet at E-. Miami limestone was encountered below the sand with limestone fragments at E- and extended to the exfiltration test depth of 5 feet below grade. Limestone was typically encountered at the remaining test locations at depths ranging between 2 and 5 feet below grade and extended to the exfiltration test termination depths of 5 feet. The groundwater level was recorded at the exfiltration test locations during the augering process. During the subsurface exploration, groundwater (measured in August) was typically observed at the test locations at depths ranging from 3 to 6 feet below existing grade. Exceptions exist at test locations E-2 and E-3 where groundwater levels were encountered at approximately 0½ feet and 3 feet, respectively. These water level observations provide an approximate indication of the groundwater conditions existing on the site at the time the borings were drilled. Fluctuations in the groundwater table can occur due to seasonal variations, recent rainfall conditions and other site specific conditions. Therefore, at the time of the year different from the time of drilling, there is a possibility of a change in the recorded level. We estimate that during the peak of the wet hydroperiod, with rainfall and recharge at a maximum, groundwater level at the site could be one to five feet higher than those measured in the borings. This possibility should be considered when developing design and construction plans and specifications for the project. Long term monitoring in cased holes or piezometers would be necessary to accurately evaluate the potential range of groundwater conditions at the site. Asphalt core samples were recovered from the roadway at the exfiltration test locations by J&R Precision Drilling, Inc. A total of nine (9) 4-inch diameter cores were taken. Once the cores were extracted, they were transported to our laboratory in Sunrise, Florida. A summary of the test results and asphalt core thicknesses are presented in the following table. More detailed test information can be found in the attachments included with this letter. Test Location Hydraulic Conductivity (cfs/ft 2 ft.head) TABLE : Exfiltration Test Results Asphalt Thickness (in.) Test Location Hydraulic Conductivity (cfs/ft 2 ft.head) Asphalt Thickness (in.) E- 5.5 x 0-6.99 E-4 2.25 x 0-4 2.60 E-2.09 x 0-5 2.22 E-5 8.5 x 0-4 2.70 E-3 4.56 x 0-3.74 E-6 5.63 x 0-5.7
EFILTRATION TEST LOG - E- Client: C3TS Job # 3409509 Site: NW 7th Avenue and NW 7th Street Test # Project: Glenroyal East Phase Roadway and Drainage Improvements Date: 8/9/2009 6.50 Auger Diameter: 0 inches Tube : 5 Ft Increment Gal/Min 0.5 2 0.5 3 0.3 4 0.3 5 0.3 6 0.3 7 0.3 2 -INCH ASPHALT 8 0.3 0.0-9.0 SAND, fine, brown 9 0.3 9.0-3.0 SAND, with limestone fragments, fine, brown 0 0.3 3.0-5.0 LIMESTONE, with sand, light brown Q = Average Stabilized Rate: 0.3 Gal/Min H = to Groundwater Level: 6.5 Ft Ds = Saturated : 8.5 Ft D = of Hole: 5 Ft Hydraulic Conductivity 5.5E-06 cfs/ft 2 ft.head
EFILTRATION TEST LOG - E-2 Client: C3TS Job # 3409509 Site: NW 7th Avenue and NW 7th Street Test # 2 Project: Glenroyal East Phase Roadway and Drainage Improvements Date: 8/9/2009 0.50 Auger Diameter: 0 inches Tube : 5 Ft Increment Gal/Min.0 2.0 3 0.8 4 0.8 5 0.8 6 0.8 7 0.8 2 /4-INCH ASPHALT 8 0.8 0.0-5.0 FILL-SAND, with limerock, fine, brown 9 0.8 5.0-5.0 LIMESTONE, with sand, light brown to gray 0 0.8 Q = Average Stabilized Rate: 0.8 Gal/Min H = to Groundwater Level: 0.5 Ft Ds = Saturated : 4.5 Ft D = of Hole: 5 Ft Hydraulic Conductivity.09E-05 cfs/ft 2 ft.head
EFILTRATION TEST LOG - E-3 Client: C3TS Job # 3409509 Site: NW 7th Avenue and NW 7th Street Test # 3 Project: Glenroyal East Phase Roadway and Drainage Improvements Date: 8/20/2009 3.00 Auger Diameter: 0 inches Tube : 5 Ft Increment Gal/Min 35.0 2 35.0 3 35.0 4 35.0 5 35.0 6 35.0 7 35.0 3/4-INCH ASPHALT 8 35.0 0-0.0 FILL-LIMEROCK, with sand, light brown 9 35.0 0.0-5.0 LIMESTONE, with sand, tan 0 35.0 Q = Average Stabilized Rate: 35.0 Gal/Min H = to Groundwater Level: 3 Ft Ds = Saturated : 2 Ft D = of Hole: 5 Ft Hydraulic Conductivity 4.56E-03 cfs/ft 2 ft.head Values adjusted since groundwater was not able to be raised to the surface.
EFILTRATION TEST LOG - E-4 Client: C3TS Job # 3409509 Site: NW 7th Avenue and NW 7th Street Test # 4 Project: Glenroyal East Phase Roadway and Drainage Improvements Date: 8/2/2009 4.33 Auger Diameter: 0 inches Tube : 5 Ft Increment Gal/Min 2.0 2.0 3 0.0 4 8.0 5 8.0 6 8.0 7 8.0 2 /2-INCH ASPHALT 8 8.0 0.0-3.0 FILL-LIMEROCK, with sand, fine, light brown 9 8.0 3.0-5.0 LIMESTONE, with sand, brown 0 8.0 Q = Average Stabilized Rate: 8.9 Gal/Min H = to Groundwater Level: 4.33 Ft Ds = Saturated : 0.7 Ft D = of Hole: 5 Ft Hydraulic Conductivity 2.25E-04 cfs/ft 2 ft.head
EFILTRATION TEST LOG - E-5 Client: C3TS Job # 3409509 Site: NW 7th Avenue and NW 7th Street Test # 5 Project: Glenroyal East Phase Roadway and Drainage Improvements Date: 8/20/2009 3.50 Auger Diameter: 0 inches Tube : 5 Ft Sample Location: Increment Gal/Min 30.0 2 28.0 As shown on Exfiltration Test Location Diagram 3 27.0 4 28.0 5 28.0 6 28.0 7 28.0 2 3/4-INCH ASPHALT 8 28.0 0-2.0 SAND, trace limerock, fine, brown 9 28.0 2.0-5.0 LIMESTONE, with sand, light gray to brown 0 28.0 Q = Average Stabilized Rate: 28. Gal/Min H = to Groundwater Level: 3.5 Ft Ds = Saturated :.5 Ft D = of Hole: 5 Ft Hydraulic Conductivity 8.5E-04 cfs/ft 2 ft.head
EFILTRATION TEST LOG - E-6 Client: C3TS Job # 3409509 Site: NW 7th Avenue and NW 7th Street Test # 6 Project: Glenroyal East Phase Roadway and Drainage Improvements Date: 8/20/2009 5.50 Auger Diameter: 0 inches Tube : 5 Ft Increment Gal/Min 3.5 2 3.5 3 2.5 4 2.5 5 2.5 6 2.5 7 2.5 3/4-INCH ASPHALT 8 2.5 0-3.0 FILL-SAND, with limerock, fine, light brown 9 2.5 3.0-5.0 LIMESTONE, with sand, light gray to brown 0 2.5 Q = Average Stabilized Rate: 2.7 Gal/Min H = to Groundwater Level: 5.5 Ft Ds = Saturated : 9.5 Ft D = of Hole: 5 Ft Hydraulic Conductivity 5.63E-05 cfs/ft 2 ft.head
EFILTRATION TEST LOG - E-7 Client: C3TS Job # 3409509 Site: NW 7th Avenue and NW 7th Street Test # 7 Project: Glenroyal East Phase Roadway and Drainage Improvements Date: 8/2/2009 4.00 Auger Diameter: 0 inches Tube : 5 Ft Sample Location: Increment Gal/Min 0.0 2 9.0 As shown on Exfiltration Test Location Diagram 3 9.0 4 9.0 5 9.0 6 9.0 7 9.0 4 3/4-INCH ASPHALT 8 9.0 0 -.0 FILL-SAND, with limerock, fine, brown 9 9.0.0-5.0 LIMESTONE, with sand, tan 0 9.0 Q = Average Stabilized Rate: 9. Gal/Min H = to Groundwater Level: 4 Ft Ds = Saturated : Ft D = of Hole: 5 Ft Hydraulic Conductivity 2.46E-04 cfs/ft 2 ft.head
EFILTRATION TEST LOG - E-8 Client: C3TS Job # 3409509 Site: NW 7th Avenue and NW 7th Street Test # 8 Project: Glenroyal East Phase Roadway and Drainage Improvements Date: 8/20/2009 3.50 Auger Diameter: 0 inches Tube : 5 Ft Increment Gal/Min 8.0 2 7.0 3 7.0 4 7.0 5 7.0 6 7.0 7 7.0 3-INCH ASPHALT 8 7.0 0-2.0 FILL-SAND, fine, brown 9 7.0 2.0-3.0 FILL-LIMEROCK, with sand, brown 0 7.0 3.0-5.0 LIMESTONE, with sand, tan Q = Average Stabilized Rate: 7. Gal/Min H = to Groundwater Level: 3.5 Ft Ds = Saturated :.5 Ft D = of Hole: 5 Ft Hydraulic Conductivity 2.5E-04 cfs/ft 2 ft.head
EFILTRATION TEST LOG - E-9 Client: C3TS Job # 3409509 Site: NW 7th Avenue and NW 7th Street Test # 9 Project: Glenroyal East Phase Roadway and Drainage Improvements Date: 8/2/2009 4.00 Auger Diameter: 0 inches Tube : 5 Ft Increment Gal/Min 0.0 2 9.0 3 7.0 4 5.0 5 5.0 6 5.0 7 5.0 4 /2-INCH ASPHALT 8 5.0 0-2.0 FILL-SAND, with limerock, fine, brown 9 5.0 2.0 5.0 LIMESTONE, with sand, tan 0 5.0 Q = Average Stabilized Rate: 6. Gal/Min H = to Groundwater Level: 4 Ft Ds = Saturated : Ft D = of Hole: 5 Ft Hydraulic Conductivity.65E-04 cfs/ft 2 ft.head