Below follows a short extract from a description of events that took place between the end of April and early May 2009 provided by the Project Manager’s Representative (Babtie Fichtner) followed by a series of photographs taken by him on 28th April 2009. The reader may draw his or her own conclusion about what in fact took place on the site during construction.
“There were four extract well points drilled into the bottom of the excavation pit and another four discharge points drilled outside of the sheet pile curtain. The intention of CSBC, (consortium of contractors) as described in their Risk Assessment and Method Statement (RAMS), was to pump sea water from the extract wells, sub-surface, before it entered the excavation, over the sheet pile wall and discharge into the well points located outside of the sheet pile curtain. This was tried on a number of occasions and proven to be unsuccessful, due to the discharge wells being flooded with the incoming tide so the water that was being pumped from the extract wells had nowhere to go.
I have copies of e mails questioning the methodology for this activity but, as was usually the case, my questions were never fully answered or ignored. The habitual late submission of these and similar documents caused me many problems when trying to get an acceptable methodology in place before work commenced. Fitchtner frequently instructed me not to stop CSBC just because of paperwork not being in place, so I was continuously battling against CSBC starting activities which were not adequately planned or supervised and TTS’s/Fichtner’s concerns over the lack of progress. I also have records of minutes of meetings where my dissatisfaction over the late submission of documents has been recorded and TTS were aware of the situation.
You will note that the report, incorrectly in my opinion, states that the pollution in the sea would be unlikely caused by the pumping into the well discharge point; Before the sheet pile curtain was completed the sea entered the excavation on a twice daily basis and left, taking any pollutants with it along the stone fill around the culvert, which was acting like a french drain and facilitated the quick and easy emptying of tidal water.
This was common knowledge and although I raised my concerns was the case until such time the sheet pile curtain was in satisfactory condition to keep the majority of tidal water away from the excavation. However, there was still some water entering the excavation which the sheet piles helped to retain within the excavation, thus preventing work from proceeding as efficiently as CSBC desired. On a weekly basis I asked CSBC why the settlement tanks were not being used to demonstrate to the EPO that water could be treated as they suggested in their discharge consent application. To be honest the entire system was undersized and useless for the purposes it was intended. This was brought to their attention by me and also recorded in minutes which I have available. Because they couldn’t get rid of the water held within the excavation they proceeded to use less scrupulous methods to empty the excavation.
The above photograph, taken by me on the 28th April at approximately 4pm shows water being pumped direct from the excavation. This was in contravention of agreements made between the EPO and CSBC to use the extract wells to prevent contaminated water entering the discharge wells outside of the sheet pile curtain and the Risk Assessment and Method Statement (RAMS) produced to show how de-watering was to be carried out.
The photograph above, one of several taken between 4pm and 4.15 on the 28th April, shows discolouration of the sea. The photograph does not show the full extent of the pollution. I instructed CSBC to stop work immediately and told the CSBC Safety Officer to arrange for samples to be taken of the sea. This had not been observed before on site and I am convinced that this was due to the pumping of very dirty water from the bottom of the excavation.
Although CSBC had spent many hours trying to seal up the sheet pile curtain at the culvert side there was still water ingress being encountered through the curtain, at both sides of the excavation and through the bottom of the excavation. (The first picture shows the extend of the water lying in the bottom of the excavation on the morning of the 28th April.) After the culvert was originally constructed it was backfilled with shale and loose rock, so once exposed represented an easy path-way for tidal waters to travel along the outside of the culvert and then into the excavation via the sheet pile curtain which was, at this time, not fully water tight.
Water also entered the excavation via fissures at the opposite end of the excavation and through the bottom which I believe were created during both the original blasting, required to construct the culvert and again by the blasting which took place to facilitate the EfW excavation to be carried out. The photograph above shows water sitting on top of the culvert during high tide on the morning of the 28th April. You will note the scum on the top of the water. This was I believe, in this instance, caused by sand which CSBC had used to try and seal up the gap between the culvert side and the sheet pile curtain. I have other photographs showing this type of scum throughout the excavation. I had frequently, over the space of two months asked CSBC to procure a floating boom, in an attempt to control the spread of floating debris and suspended solids, but to no avail.”
This photograph (right), taken on the morning of the 28th April, shows that the connection between the second settlement tank and the oil separator had not yet been made. So this demonstrates that the settlement tank system had not yet been operational up to the 28th April.
I had, on a number of occasions questioned the suitability and sizing of the settlement tanks and in particular the oil separator. At a later date the settlement tanks were used and the separator silted up and overflowed to the sea. The outlet side of the second settlement tank, not connected to the oil separator and the water level not up to the weir level of the first tank to send it to the second tank (yellow tank) is the second settlement before it was supposed to go to the oil separator.
The last photograph shows settlement tank number 2 empty on the morning of the 28th April, demonstrating that the system was not in use.