Retrospective Evaluation of Cured-in-Place Pipe - (NEPIS)(EPA ...

5.2.2 Timeline for Fieldwork
Tuesday, April 13, 2010
7:30 AM Contractor’s (Bale) crew began staging equipment and preparing the site for the
excavation.
8:00 AM Excavation began on asphalt roadway. The asphalt layer was approximately 4 in. thick
with 4 in. of road base material compacted beneath. The excavation was carried out
between manholes 0233S0013 and 0233S0010, from 254 ft to 264 ft west of manhole
0233S0013.
8:05 AM After removal of the asphalt pavement, a soil sample was taken at the sub-grade level.
Sample No. 1 was collected and placed in a 1 gallon plastic bag. All samples were
collected with a spade shovel and hand loaded into sample containers.
8:30 AM Excavation was halted and sample No. 2 was collected from the bottom of the trench at a
depth of 3 ft.
9:45 AM In-service, 4 in. diameter, vitrified clay lateral was encountered. The lateral entered the
main line from the south with a 90° bend. At the connection, concrete was poured to assist
in keeping the lateral in place at the main line. No noticeable leaking was detected in this
area. There was also a second, inactive lateral on the north side of the excavation.
10:00 AM Excavation encountered crown of pipe. Excavation was halted and sample No. 3 was
collected from 6 ft below grade and immediately above the crown of the pipe. Sample No.
4 was collected from the side of the trench at elevation 5 ft below grade.
10:05 AM Excavation activity entered the area surrounding and below the pipe. Formation l consisted
predominantly of native shale. Visual observation suggested good compaction around the
pipeline. The bedding material was undisturbed with a solid beam support and good
support at the spring lines. Normal condensation was observed around the outside of the
clay host pipe. The clay host pipe was installed with 2 ft joints.
10:55 AM Sample No. 5 was collected with continued hand digging at the spring line level of the
pipe.
11:10 AM Sample No. 6 was collected with continued hand digging at the invert of the pipe.
Bedding beneath the invert consisted mainly of native shale. Traces of excess resin from
the installation were observed and a resin sample collected for future consideration.
11:30 AM Once the line was 90% exposed, shims and bracing were used to support the host pipe.
The pipe was lashed to a wooden support structure and layers of the shrink wrap material
were applied. Two lifting slings were then fitted to the pipe specimen and the excavator. It
should be noted that the host pipe with CIPP was not fully supported several times during
the excavation and removal process, acting as a simple supported beam. One section of
lateral was damaged during excavation and was removed so that the excavation around the
pipe could be completed.
14:00 AM One wastewater sample (Richards-8) was collected for pH and total petroleum
hydrocarbons (TPH) including gasoline range organics (GRO) and diesel range organics
(DRO).
14:05 PM Another wastewater sample (Richards-8D) was collected for pH and TPH GRO/DRO.
14:15 PM The shoring box was set and a temporary line was put in place for the lateral that was
removed. Steel plates were placed over the excavation and cold patch around the edges.
15:15 PM Measurements of the annular gap between the host pipe and liner were taken using a feeler
gauge at both ends of the specimen and at both ends of the remaining pipe before the repair
is made.
15:30 PM The construction crew finished wrapping the specimen and loaded the specimen into the
bed of a truck.
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