Japanese N-Plant Explosion

[iceaura]

"The density detected in the plutonium is equivalent to the density in the soil under normal environmental conditions and therefore poses no major impact on human health," TEPCO said

The density of plutonium in the soil under "normal environmental conditions" is zero, anywhere on earth. It's all radioactive waste from nuclear weapons and power production. Its impact on human health depends on circumstance.

The idea that plutonium waste is "normal" and that "therefore" it poses no risk to human health is one of the several incredible and baffling standard lines of bs that have cost the industry all of its credibility among the informed and responsible.

If the nuclear industry wants to complain about people overreacting to things like "nuclear" and "radiation", they have to quit lying to people like that. As things stand, no one with a lick of sense is going to take their word for anything, and why should they?

 

[adoucette]

Not a lie.

Since the Japanese did not set off any of the above ground nuclear tests done decades ago (that would be US, France, UK and Russia), but their soil got contaminated by them, I think it is perfectly reasonable for them to discuss what is now the normal levels of these elements that are found in their soil.

And no, they are not lying when they state that there are no known MAJOR impacts to human health from these incredibly low levels of radiation.

Arthur

 

[Trippy]

The density of plutonium in the soil under "normal environmental conditions" is zero, anywhere on earth. It's all radioactive waste from nuclear weapons and power production. Its impact on human health depends on circumstance.

The idea that plutonium waste is "normal" and that "therefore" it poses no risk to human health is one of the several incredible and baffling standard lines of bs that have cost the industry all of its credibility among the informed and responsible.

If the nuclear industry wants to complain about people overreacting to things like "nuclear" and "radiation", they have to quit lying to people like that. As things stand, no one with a lick of sense is going to take their word for anything, and why should they?

This is what happens when you cherry pick, and present things out of context.

 

[iceaura]

I've made the point repeatedly - I was even correct on my prediction about this being a complex event made up of multiple ruptures (the significance of which I am confident will continue to elude you).

Much as I am grateful for the examples you keep supplying in support of my argument here, I can't help but think you can do better.
and sure enough:

Some faults, for any number of reasons (of which morphology is one) will never produce earthquakes larger than those that they already have. They are simply incapable of storing sufficient energy to produce an M8+ quake.

I'm sure that's true. I'm a bit amused at the obliviousness of its inclusion here.

We don't have a secure and comprehensive geological understanding of earthquakes. We are building nuclear power plants anyway. That's the situation.
”
No.
You simply do not understand the depth of the knowledge that we do have. There's a fundamental difference.

The evidence seems to support my view of the depth of knowledge we have in this field. One might almost describe it as "overwhelming" support.

But the principle is the fundamental issue: Do you think we should base our views on other people's depth of knowledge, our estimations of its reliability and the size risks we may safely take on its basis

on facts and evidence and reasoning, or should we take their word for it?

All of this comes down to that question that I stated at this point must become the most important question to ask, but you dismissed.

I dismissed its urgency, not its importance, and in the field of designing, siting, and operating nuclear power plants, not life in general.

But if you want to treat it as urgent, that would be OK with me: let's shut down all the fault line nukes, halt all construction, and mothball all future nuke plans and designs, etc, until it's answered with the necessary confidence - ie by a mature and comprehensively capable science, decades from now.

 

[Trippy]

The density of plutonium in the soil under "normal environmental conditions" is zero, anywhere on earth. It's all radioactive waste from nuclear weapons and power production. Its impact on human health depends on circumstance.

The idea that plutonium waste is "normal" and that "therefore" it poses no risk to human health is one of the several incredible and baffling standard lines of bs that have cost the industry all of its credibility among the informed and responsible.

If the nuclear industry wants to complain about people overreacting to things like "nuclear" and "radiation", they have to quit lying to people like that. As things stand, no one with a lick of sense is going to take their word for anything, and why should they?

This is also precisely wrong.
Plutonium does actually occur in Nature under "normal environmental conditions".
The process involves a U-238 nucleus undergoing a natural fission event, which releases neutrons, one of which is absorbed by a neighbouring U-238 atom, which undergoes two beta decays (U-239 -> Np-239 -> Pu-239) to produce plutonium, which has been detected in Cigar Lake Mine and Lake Oklo.

 

[iceaura]

This is also precisely wrong.
Plutonium does actually occur in Nature under "normal environmental conditions".

Not in the soil.

And not at the levels detected by TEPCO.

You don't read carefully, is your initial problem here. Then you use your misreading to misrepresent arguments, instead of engaging them. The net result is irrelevancy - no matter how well dressed in technicalities.

 

[Trippy]

Much as I am grateful for the examples you keep supplying in support of my argument here, I can't help but think you can do better.

Quit cherry picking.

and sure enough: I'm sure that's true. I'm a bit amused at the obliviousness of its inclusion here.

Actually, I would go as far as saying that it's true of every fault, but I'm sure you wouldn't be able to understand how it could be true of what happened in Japan, even though I've already told you.

The evidence seems to support my view of the depth of knowledge we have in this field. One might almost describe it as "overwhelming" support.

No, once again, you don't understand it. There's a distinct difference, and I wouldn't have called it terribly subtle either, but it constitutes part of what allowed me to correctly predict that this event was a complex event involving multiple ruptures.

But the principle is the fundamental issue: Do you think we should base our views on other people's depth of knowledge, our estimations of its reliability and the size risks we may safely take on its basis.

on facts and evidence and reasoning, or should we take their word for it?

Yes. I'll take the opinion of a trained Geotech over yours any day - why? Because they're in the best position to interpret the evidence.

I dismissed its urgency, not its importance, and in the field of designing, siting, and operating nuclear power plants, not life in general.

And in doing so, you completely failed to grasp its significance. It really is that simple.

But if you want to treat it as urgent, that would be OK with me: let's shut down all the fault line nukes, halt all construction, and mothball all future nuke plans and designs, etc, until it's answered with the necessary confidence - ie by a mature and comprehensively capable science, decades from now.

It has the neccessary confidence, you just don't understand the science behind it - as demonstrated in the post that I'm responding to. I don't think that you've even stopped to realize the significance of my being able to correctly predict that this was a complex failure comprised of multiple events. The science is more capable and more mature than you actually understand.

But hey, if you want to shut down all the nukes in the US, that's fine with me, I don't actually give a shit, I have no vested interest in them, just as long as you, personally, are willing to make the sacrifices neccessary to make up the 23% shortfall, and don't sit around bitching about the neccessary rolling black outs, and frequent brown outs.

For that matter, I also don't want to see you complaining about the destruction of natural habitats when they start putting up Hydro dams, wind farms, solar farms, tidal turbines, geothermal stations and so on and so forth, to fill the shortfall, or the pollution of the neccessary coal stations.

 

[Trippy]

Predictable.

Not in the soil.

Strawman hypothesis - I didn't claim it was in the soil, only that it was natural.

And not at the levels detected by TEPCO.

Strawman hypothesis - I didn't claim that it was present at the levels detected by Tepco, only that it was present.

You don't read carefully, is your initial problem here. Then you use your misreading to misrepresent arguments, instead of engaging them. The net result is irrelevancy - no matter how well dressed in technicalities.

Actually, I read very carefully.

 

[Trippy]

Not in the soil.

And not at the levels detected by TEPCO.

You don't read carefully, is your initial problem here. Then you use your misreading to misrepresent arguments, instead of engaging them. The net result is irrelevancy - no matter how well dressed in technicalities.

Having said that that, you're demonstrating your ignorance again, because there's a chain of logic here that follows from my deomnstration that Plutonium occurs naturally in Ores and Bastnäsite (of course Monazite and Rock Phosphate can also have naturally high levels of Uranium in them (and therefore represent natural sources of Plutonium that can enter the soil) In some places there are placer deposits that have mineable quantities of Monazite. Placer Deposits are sand, which counts as soil (One source of Monazite, AFAIK is Pegmatites).

Soil ultimately derives from chemical and biological weathering of bedrock.
Any trace elements - including Plutonium - present in the bedrock, have the potential to wind up in the soil - depending on a bunch of stuff to do with soil chemistry and such.

So to sum up.
Plutonium naturally occurs in Uranium Deposits.
Plutonium naturally occurs in minerals and some bedrock.
Where plutonium occurs in bedrock or mineral deposits, it is both possible and probable that the Plutonium will also be present in the soil.

 

[Trippy]

The density of plutonium in the soil under "normal environmental conditions" is zero, anywhere on earth. It's all radioactive waste from nuclear weapons and power production. Its impact on human health depends on circumstance.

The idea that plutonium waste is "normal" and that "therefore" it poses no risk to human health is one of the several incredible and baffling standard lines of bs that have cost the industry all of its credibility among the informed and responsible.

If the nuclear industry wants to complain about people overreacting to things like "nuclear" and "radiation", they have to quit lying to people like that. As things stand, no one with a lick of sense is going to take their word for anything, and why should they?

As well as cherry picking, it's a red herring, because what there saying amounts to "Actually, it looks like most[sup]*[/sup] of the Putonium we've detected appears to have been a result of events that predate this incident, rather than as a consequence of this incident"

[sup]*[/sup]Most, in this context referring to the number of samples, rather than the quantity of Plutonium in individual samples.

 

[Trippy]

And for those that are interested:

 

[chimpkin]

Don't remember if this has been linked yet....
http://www.newsdaily.com/stories/tre72s2ua-us-japa-nuclear-risks/

The research paper concluded that there was a roughly 10 percent chance that a tsunami could test or overrun the defenses of the Fukushima Daiichi nuclear power plant within a 50-year span based on the most conservative assumptions.

But Tokyo Electric did nothing to change its safety planning based on that study, which was presented at a nuclear engineering conference in Miami in July 2007

Sakai's team determined the Fukushima plant was dead certain to be hit by a tsunami of one or two meters in a 50-year period. They put the risk of a wave of 6 meters or more at around 10 percent over the same time span.

In other words, Tokyo Electric scientists realized as early as 2007 that it was quite possible a giant wave would overwhelm the sea walls and other defenses at Fukushima by surpassing engineering assumptions behind the plant's design that date back to the 1960s.

 

[Trippy]

Don't remember if this has been linked yet....
http://www.newsdaily.com/stories/tre72s2ua-us-japa-nuclear-risks/

Yes, and the plant was also supposed to have been decomissioned this year, but was relicensed instead - there may have been conditions around improving Def V Tsunami, however...

 

[adoucette]

Don't remember if this has been linked yet....
http://www.newsdaily.com/stories/tre72s2ua-us-japa-nuclear-risks/

The assumtion made is not correct.

Sakai's team determined the Fukushima plant was dead certain to be hit by a tsunami of one or two meters in a 50-year period. They put the risk of a wave of 6 meters or more at around 10 percent over the same time span.

In other words, Tokyo Electric scientists realized as early as 2007 that it was quite possible a giant wave would overwhelm the sea walls and other defenses at Fukushima by surpassing engineering assumptions behind the plant's design that date back to the 1960s.

As we have seen the plant was built on a bluff, so it was quite a bit higher than 6 meters above the ocean. (it was built ~13 meters above the sea).

So if there is a 10% chance of a Tsunami > 6 meters over 50 years it's quite likely the chance of a Tusunami > 8 meters would be half or less than that, and one of 10 meters much much less than that and one > 12 meters nearly zero.

So actually, that paper was probably somewhat reassuring.

Arthur

 

[iceaura]

So to sum up.
Plutonium naturally occurs in Uranium Deposits.
Plutonium naturally occurs in minerals and some bedrock.
Where plutonium occurs in bedrock or mineral deposits, it is both possible and probable that the Plutonium will also be present in the soil.

To reiterate, then, since we apparently agree on the point: Plutonium is not found in the soil under "normal environmental conditions" anywhere on this planet.

From which we note: The levels found are not normal amounts found in soil under normal environmental conditions, such as humans have thousands of years of experience with and a reasonable inference of safety from. Safety cannot be inferred from the levels of plutonium found in the soil near this reactor. Implying such safety, inferring such safety, supporting such implications and inferences by technospeak and weasel wordings, etc, is not reasonable.

As well as cherry picking, it's a red herring, because what there saying amounts to "Actually, it looks like most* of the Putonium we've detected appears to have been a result of events that predate this incident, rather than as a consequence of this incident"

That is exactly and critically not what they are saying, differing in the central and crucial detail of inferred safety from normal environmental circumstance. They are deliberately and precisely obscuring the fact that plutonium in the soil of Japan is due to events - recent human caused disasters, accidents, horrific assaults; recent and bad effects of human doings,

->from which the safety of normal experience and long familiarity cannot be inferred.<-

Which of course is central and directly relevant to my arguments here.

Attempts to describe quantities of plutonium as the amounts expected in soil under "normal environmental conditions", in transparent and bogus attempts to reassure people of their safety and the general safety of industrial practices that manufacture and use plutonium, are dishonest. The people making these attempts are lying scum, attempting to regain narrative control in the wake of their latest disaster.

Successfully, if the suckered experts on this thread are a fair sample of the general information sources we will be seeing on our major media for months - as seems probable, from the media handling so far.

(btw: No, placer sand deposits are not "soil" in any reasonable, ordinary technical, or especially major media useful sense of the term - http://en.wikipedia.org/wiki/Placer_deposit.

Neither is mine waste, exposed and weathering bedrock, alluvial mineral deposits in stream beds, etc)

So if there is a 10% chance of a Tsunami > 6 meters over 50 years it's quite likely the chance of a Tusunami > 8 meters would be half or less than that, and one of 10 meters much much less than that and one > 12 meters nearly zero.

So actually, that paper was probably somewhat reassuring.

Anyone who has ever been reassured by handwaving about "nearly zero" based on the contemporary state of earthquake prediction (forecasting, odds setting, etc) should be excluded from the design and siting decisions of nuclear power plants, now and from now on.

 

[adoucette]

Anyone who has ever been reassured by handwaving about "nearly zero" based on the contemporary state of earthquake prediction (forecasting, odds setting, etc) should be excluded from the design and siting decisions of nuclear power plants, now and from now on.

Not at all.
The Reactors themselves got through this fine.
They did not provide adequate protection to the back-up power supplies though.
Actually a fairly easy thing to fix in future siting, even at this site.

My guess is they will come to that conclusion and continue to operate Reactors 5 & 6, but with more thought to where the fuel and diesel generators are located (Really no need for them to even be that close to the site).

I suspect that this re-examination of the existing plans to ensure back up power will go on across Japan and the rest of the users of Nuclear power, because what we have learned is the Reactors themselves are quite resilient and the amount of radiation released, even in this worse case scenario has been relatively modest and had better provisions for back-up power been provided, it would have been zero.

Even so, without access to grid power for 10+ days.

Death toll from these reactors remains at zero.

Members of the Public that have been seriously exposed to radiation remains at zero.

Arthur

 

[Trippy]

To reiterate, then, since we apparently agree on the point: Plutonium is not found in the soil under "normal environmental conditions" anywhere on this planet.

Yes, it is. That's what I just got through explaining.

From which we note: The levels found are not normal amounts found in soil under normal environmental conditions, such as humans have thousands of years of experience with and a reasonable inference of safety from.

In the context of cold-war atmospheric tests, yes, they are normal levels. You've constructed a house of cards.

Safety cannot be inferred from the levels of plutonium found in the soil near this reactor. Implying such safety, inferring such safety, supporting such implications and inferences by technospeak and weasel wordings, etc, is not reasonable.

Yes, it can, from a number of lines of evidence.[/quote]

That is exactly and critically not what they are saying, differing in the central and crucial detail of inferred safety from normal environmental circumstance. They are deliberately and precisely obscuring the fact that plutonium in the soil of Japan is due to events - recent human caused disasters, accidents, horrific assaults; recent and bad effects of human doings.

Conspirational poppycock.

->from which the safety of normal experience and long familiarity cannot be inferred.<-

Bullshit.

Which of course is central and directly relevant to my arguments here.

Attempts to describe quantities of plutonium as the amounts expected in soil under "normal environmental conditions", in transparent and bogus attempts to reassure people of their safety and the general safety of industrial practices that manufacture and use plutonium, are dishonest. The people making these attempts are lying scum, attempting to regain narrative control in the wake of their latest disaster.

Successfully, if the suckered experts on this thread are a fair sample of the general information sources we will be seeing on our major media for months - as seems probable, from the media handling so far.

The only person making shit up here is you.

(btw: No, placer sand deposits are not "soil" in any reasonable, ordinary technical, or especially major media useful sense of the term - http://en.wikipedia.org/wiki/Placer_deposit.

Bullshit.

Eluvium on Wiki

In geology, eluvium or eluvial deposits are those geological deposits and soils that are derived by in situ weathering or weathering plus gravitational movement or accumulation...

...The strict eluvial horizon (E horizon) is typically light gray, clay-depleted, contains little organic matter and has a high concentration of silt and sand particles composed of quartz and other resistant minerals.

Eluvial ore deposits are those such as tungsten and gold placer deposits formed by settling and enriched by the winnowing or removal of lower density materials...

Yes, they are (or can be - and that's without even considering Eolian placers).

Neither is mine waste

I didn't claim mine waste was, did I?

exposed and weathering bedrock

I don't recall mentioning exposed bedrock, and bedrock doesn't have to be exposed to be weathering, or to be leaching minerals into the soil.

alluvial mineral deposits in stream beds

I didn't mention alluvial mineral deposits in stream beds now did - although, having said that, I have two words for you - flood plains.
Streams migrate. As they migrate their beds get incorporated into the local deposits, and form part of the soil profile.

Anyone who has ever been reassured by handwaving about "nearly zero" based on the contemporary state of earthquake prediction (forecasting, odds setting, etc) should be excluded from the design and siting decisions of nuclear power plants, now and from now on.

This is hilarious - mostly because so far most of the hand waving has been yours.

 

[iceaura]

(btw: No, placer sand deposits are not "soil" in any reasonable, ordinary technical, or especially major media useful sense of the term - http://en.wikipedia.org/wiki/Placer_deposit.
”
Bullshit.

Eluvium on Wiki

“
In geology, eluvium or eluvial deposits are those geological deposits and soils that are derived by in situ weathering or weathering plus gravitational movement or accumulation...

...The strict eluvial horizon (E horizon) is typically light gray, clay-depleted, contains little organic matter and has a high concentration of silt and sand particles composed of quartz and other resistant minerals.

Eluvial ore deposits are those such as tungsten and gold placer deposits formed by settling and enriched by the winnowing or removal of lower density materials...
”
Yes, they are (or can be - and that's without even considering Eolian placers).

Nothing in your link there, much less the quote, includes placer deposits as soil. Reread.

And my link was first, as well as specific. Read it too.

Placer deposits are sand deposits in watersheds, usually right in the water or flood zone, sometimes buried under stuff. Nobody calls them "soil" - the Japanese were not testing placer deposits for plutonium, and if they had been they would not have referred to them as "soil".

Why are you dealing this semantical bs, anyway? Are you defending the TEPCO media handout language?

In the context of cold-war atmospheric tests, yes, they are normal levels.

In the context of "normal environmental conditions" - the long familiar environment from which safety can be reasonably inferred - they aren't.

I didn't claim mine waste was, did I?
- - -
exposed and weathering bedrock
- - -
I don't recall mentioning exposed bedrock, and bedrock doesn't have to be exposed to be weathering, or to be leaching minerals into the soil.
- - -
I didn't mention alluvial mineral deposits in stream beds now did .

After your bullshit about placer deposits, I covered what obvious weasels I could see you eying - including all the normal circumstances of placer deposition.

To reiterate: plutonium is not found in soil under "normal environmental conditions" (the kind of long familiarity and extended experience) from which safety can be inferred. Wherever it is found in soil, it is recently deposited residue from the nuclear bomb and power industry.

mostly because so far most of the hand waving has been yours.

Uh, no - here's one of the major handwavers on this thread, making another dubious and quite unsupported assertion that he will (already has, my bet) find difficult to support with even one serious example (let alone the commonplace circumstances necessary to engage the actual argument involved - as this poster is not bothering with that in general, such is not expected here either):

Where plutonium occurs in bedrock or mineral deposits, it is both possible and probable that the Plutonium will also be present in the soil.

That was in alleged contradiction to my assertion that plutonium is not, in fact, present in "soil" on this planet under "normal environmental conditions".

As one can see, given some stretching on the "possible" and "probable", both assertions could easily be true. The facts on the ground, and of the ground, would remain: there isn't any "normal" plutonium in the soil, and representing the presence of bomb residue plutonium as environmentally normal and familiar, something from which safety can be inferred, is dishonest.

 

[Trippy]

Nothing in your link there, much less the quote, includes placer deposits as soil. Reread.

And my link was first, as well as specific. Read it too

Yeah, it does. You just don't recognize it, because you've never studied soil science.

Placer deposits are sand deposits in watersheds, usually right in the water or flood zone, sometimes buried under stuff. Nobody calls them "soil" - the Japanese were not testing placer deposits for plutonium, and if they had been they would not have referred to them as "soil".

True, but not exclusively true.
Placer deposits are simply deposits where heavy stuff is left behind, and light stuff carried away, this does not exclusively occur as a result of water, the water based ones (alluvial placers) are simply the most economically important.

No amount of arm waving and BS in your part is going to make the fact that Placer deposits occur as soils and soil horizons go away. Your argument thus far is a redherring or a strawman, essentially based around the fact that they retain a special name - even as soil deposits.

But hey, don't take my word for it.

Here's a gold placer deposit occuring as part of a 'Raw & Recent' soil (I suspect that all placers would fall under the 'raw and recent' category, but i'm not willing to commit to that.

Why are you dealing this bs, anyway? Are you defending the TEPCO media handout language?

I'm not dealing the BS, you are.
Something you haven't understood yet - I'm not defending Tepco, I'm attacking your inept analysis.

In the context of "normal environmental conditions" - the long familiar environment from which safety can be reasonably inferred - they aren't.

Bullshit.

After your bullshit about placer deposits, I covered what obvious weasels I could see you eying - including all the normal circumstances of placer deposition.

The only person bullshitting here is you.
You invented strawmen, because, once again, you made assumptions about me, my motivations, and my arguments. Assumptions that, once again, turned out to be wronf.

To reiterate: plutonium is not found in soil under "normal environmental conditions" (the kind of long familiarity and extended experience) from which safety can be inferred. Wherever it is found in soil, it is recently deposited residue from the nuclear bomb and power industry.

Bullshit. where you have Uranium naturally occuring in the soil, or the bedrock, the potential for Plutonium to be in the soil exists (in fact it's almost a certainty that it's there to some extent).

Uh, no - here's one of the major handwavers on this thread, making another dubious and quite unsupported assertion that he will (already has, my bet) find difficult to support with even one serious example (let alone the commonplace circumstances necessary to engage the actual argument involved - as this poster is not bothering with that in general, such is not expected here either): That was in alleged contradiction to my assertion that plutonium is not, in fact, present in "soil" on this planet under "normal environmental conditions".

More handwaving. I've provided literature to demonstrate my point, you have not.

As one can see, given some stretching on the "possible" and "probable", both assertions could easily be true. The facts on the ground, and of the ground, would remain: there isn't any "normal" plutonium in the soil, and representing the presence of bomb residue plutonium as environmentally normal and familiar, something from which safety can be inferred, is dishonest.

Bullshit and handwaving.

 

[iceaura]

Yeah, it does. You just don't recognize it, because you've never studied soil science.

I don't recognize it, because I can read English and it isn't there. You are not reading your own links, apparently - try to find the specific reference, and point to it: you'll find it impossible.

No amount of arm waving and BS in your part is going to make the fact that Placer deposits occur as soils and soil horizons go away

I am quite familiar and comfortable with the fact that placer deposits are often formed as soils and soil horizons go away - usually, washed away.

I have studied soil science, btw - yet another miss, as you have by now (multiple examples) solidly joined the forum faction that "argues" via ad hominem guesswork and personal accusation in matters they not only don't know, but can't know - and unsurprisingly is almost always wrong.

More handwaving. I've provided literature to demonstrate my point, you have not

You have provided no literature that deals with any of my points here. None.

Something you haven't understood yet - I'm not defending Tepco, I'm attacking your inept analysis.

Well, you haven't attacked anything I've said yet.

I don't think you have any idea what my argument on this thread is, actually - your volume of irrelevancy is way too big to ascribe to a tactic deriving from comprehension.

Bullshit. where you have Uranium naturally occuring in the soil, or the bedrock, the potential for Plutonium to be in the soil exists (in fact it's almost a certainty that it's there to some extent).

Cool. So where is that - we need a region (acreage big enough to be an "environment") where plutonium in the soil is among the normal environmental conditions (that is, there's enough of it to be an environmental condition - not an atom here and there, like the gold content of the atmosphere - or are you going to be just completely tiresome? ) The claim you have chosen to define and attack, for some reason, is after all a very strong one, and even one non-trivial example would do.

Notice that you have already been allowed to avoid the actual argument, and deflect things far away from anything relevant to the analysis you claim to be attacking in the first place - but you show no interest in that, and threads are allowed tangents, so - - - -