in the method 10 as representatively depicted in fig1 a wellbore 12 has been drilled intersecting a formation or zone of interest 14 and the wellbore has been lined with casing 16 and cement 17 in the further description of the method 10 below the wellbore 12 is referred to as the interior of the casing 16 but it is to be clearly understood that with appropriate modification in a manner well understood by those skilled in the art a method incorporating principles of the present invention may be performed in an uncased wellbore and in that situation the wellbore would more appropriately refer to the uncased bore of the well a tubular string 18 is conveyed into the wellbore 12 the string 18 may consist mainly of drill pipe or other segmented tubular members or it may be substantially unsegmented such as coiled tubing at a lower end of the string 18 a formation test assembly 20 is interconnected in the string the assembly 20 includes the following items of equipment in order beginning at the bottom of the assembly as representatively depicted in fig1 one or more generally tubular waste chambers 22 an optional packer 24 one or more perforating guns 26 a firing head 28 a circulating valve 30 a packer 32 a circulating valve 34 a gauge carrier 36 with associated gauges 38 a tester valve 40 a tubular surge chamber 42 a tester valve 44 a data access sub 46 a safety circulation valve 48 and a slip joint 50.