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nigelswift N
nigelswift Nov 26, 2005 22:24:42
Replying to Ishmael

I am very tired, but for the record:

We didn't misinterpret anything. However,

a.>
We did believe EH's Risk Assessment document, (section 8.3.3.3) when it said "For re-entry into the tunnels the amount of mechanical damage is calculated on the basis of tunnel enlargement by 0.2m around the existing roof and sides, along all of the 1849 and 1968-69 tunnelling. The figure here for new damage is 166m3 ".

Today, EH said that's not what they meant "in their wildest dreams" and they were aiming to go in on the basis of zero damage or a minimum amount. We look forward to seeing that in print and for the Risk Assessment to be amended to say that there will be no tunnel enlargement by 0.2m and no consequent loss of 166m3. Indeed, if they can do it we'll be the first to hail the miracle.

b.>
At the other end of the scale, we did believe EH's Risk Assessment document (Section 8.3) which calculated the rate of natural collapse, if nothing was done to be very slow and would take many hundreds of years to take place. From this, we had inferred that it would take 107 years before the equivalent damage to the tunnelling damage would occur. Today, their consultant engineer said he did not know how long the natural process would take and he had been pressured to provide those figures. (Not by us, please note. As if.)

So, we were guilty of believing EH's Risk Assessment. In the event, in the two most crucial matters relating to their intention to tunnel, they say we were quite wrong to do so and we must of course accept their word.

(PS - Pete, I have approached this diligently and to the best of my ability and suspect most people know that and will judge your posting on the basis of what they know of me, and of you).

S smallblueplanet
smallblueplanet Nov 26, 2005 22:34:42
Replying to nigelswift

"Today, EH said that's not what they meant "in their wildest dreams" and they were aiming to go in on the basis of zero damage or a minimum amount. We look forward to seeing that in print and for the Risk Assessment to be amended to say that there will be no tunnel enlargement by 0.2m and no consequent loss of 166m3. Indeed, if they can do it we'll be the first to hail the miracle."

The Risk Assesment is there to provide a 'worse case' scenario - thats what its done for, it doesn't mean it will happen, but is the WORST that might happen.

"So, we were guilty of believing EH's Risk Assessment. "

No you were guilty of misunderstanding the nature of a Risk Assessment.

H Hob
Hob Nov 26, 2005 22:57:41
Replying to nigelswift

>I am very tired, but for the record:

Thanks for the clarification Nigel. I'm sure you'll offer more detail as and when it's asked for and when you're not knackered.

Get yerself some kip, and dally not with the Saturday evening pseudo-trolling ;)

I Ishmael
Ishmael Nov 27, 2005 00:13:17
Replying to nigelswift

Fair comment Nigel.
I think you did well but knew this forum would degenerate rapidly so I thought a boxing analogy might be appropriate.
I was actualy shocked at the EH U-turn in public.
Sorry I couldn't stay around afterwards but I had to meet people about a stonehenge project that is imminant.

S smallblueplanet
smallblueplanet Nov 28, 2005 14:33:26
Replying to nigelswift

Here is your report on Silbury from Heritage Actions website

Heritage Action's report
By Nigel Swift (Site Inspector), [email protected]

Recently, a <b>horribly incomplete account of possible repair options has been released.</b> This has added huge concern over the form of repairs that might be chosen to our existing concern over the delay.

Surely the clear priority is to fix the hill in the most effective and efficient way possible. There is a strong lobby, though, in favour of repairs that also allow research.

Simpler and cheaper engineering solutions to the repairs appear to be available, but the little information made public seems to 'play down' these options in favour of the option that allows simultaneous research.

<b>A new and larger tunnel would be bored into the heart of the mound from the side, involving much disruption to Silbury itself, risk of additional collapse, huge expense and years of further delay.</b>.

I'll be interested to see what the new webpage says.