ATLANTA JCC - GEOTECHNICAL ENGINEERING SERVICES BUILDING L (SOIL TESTING) FIELD EXPLORATION: BASED UPON THE SEPTEMBER 26 AND OCTOBER 3, 2018 CONFERENCE CALLS, ALTHOUGH FILL SOILS PLACED DURING CONSTRUCTION OF BUILDING L EXTEND OUTSIDE THE FOOTPRINT OF THE BUILDING IT IS BELIEVED THAT THE UPPER SUBGRADE SOILS HAVE BEEN SUFFICIENTLY DISTURBED SO AS NOT TO BE REPRESENTATIVE OF THE SOILS DIRECTLY BENEATH THE SLAB. THEREFORE, CORING OR SAW CUTTING THE SLAB WILL BE NECESSARY TO TEST NEAR SURFACE FILL SOILS. WE EXPECT TESTING AT THREE LOCATIONS WITHIN THE BUILDING. BECAUSE UNDISTURBED SAMPLING USING HAND AUGER BORINGS IS LIMITED TO ABOUT 5 FEET, THREE MECHANICAL BORINGS ADVANCED BY A DRILL RIG WILL BE PERFORMED NEAR THE SOUTHWEST AND WESTERN SIDES OF THE BUILDING TO SAMPLE FILLS AT DEPTH. WE NOTE, DEPENDING UPON THE FINDINGS OF OUR PROPOSED FIELD TESTING, ADDITIONAL EVALUATION MAY BE WARRANTED. WE WILL EXTEND THE MECHANICAL BORINGS TO AN APPROXIMATE DEPTH OF 20 FEET EACH, OR SHALLOWER REFUSAL. RELATIVELY UNDISTURBED SHELBY TUBE SAMPLES OF REPRESENTATIVE SOILS WILL BE OBTAINED FOR LABORATORY TESTING. THESE TESTS WILL INCLUDE DETERMINATION OF UNIT WEIGHT AND MOISTURE CONTENT, WHICH WILL BE USED TO ASSESS THE IN-SITU DEGREE OF COMPACTION. IN ADDITION TO PERFORMING IN-PLACE DENSITY TESTS BY DRIVE-RING AND NUCLEAR GAGE METHODS DIRECTLY BENEATH THE SLAB, A SOIL TECHNICIAN WILL ALSO RUN COMPARATIVE FIELD DENSITY TESTS ADJACENT TO THE EXTERIOR SOIL BORINGS IN THE VICINITY OF BUILDING L FOR THE PURPOSE OF CORRELATING SOIL DENSITIES BETWEEN UNDISTURBED SAMPLING AND IN-SITU TESTS. THESE TESTS WILL BE TAKEN AT A SHALLOW DEPTH, APPROXIMATELY SEVERAL INCHES TO ONE FOOT BELOW EXISTING GRADES. BULK SAMPLES WILL BE OBTAINED OF THE TESTED FILL SOILS SO LABORATORY STANDARD PROCTOR CURVES CAN BE DEVELOPED. LABORATORY TESTING WILL INCLUDE: 4 STANDARD PROCTOR TESTS 4 ATTERBERG LIMITS TESTS 4 GRAIN SIZE TESTS 16 MOISTURE CONTENT TESTS 16 UNIT WEIGHT DETERMINATIONS FROM UNDISTURBED SAMPLES UP TO 2 CONSOLIDATION TESTS, IF NEEDED TESTS ARE TO BE SCHEDULED THE WEEK OF OCTOBER 8, 2018. TIME IS OF THE ESSENCES.