Whilst on the subject of Cows ... back in August there appeared a rather large hole in the County of Durham, alas my broomstick had its feathers clipped, and the extent of the damage to said hole is still up for exploration:  http://www.bbc.co.uk/news/uk-england-tyne-28927743  "A giant sinkhole that has opened up on farmland in County Durham has continued to cause increasing concern as it threatens to get bigger, a landowner said. John Hensby, 71, from Cowshill near Bishop Auckland, said he had been warned the 110ft (35m) wide chasm would grow. It opened up on Mr Henby's land, above an old lead mine, about 260ft (80m) from his house." Noted at that time https://www.youtube.com/watch?v=NUzYk6XPv2Y (headlines "sinkhole so deep you can't see the bottom .." but then “With more rain coming tomorrow and on Monday we could see a lot more of the hole.” eh? RALMHO - it started about five foot deep ... sure she she wasn't carrying a shovel? .... http://www.mirror.co.uk/.../sinkhole-deep-you-cant-see... wonder if they have a tea shop - could be an interesting day out for a Bank Holiday ..... oh well I guess thats what you get for shooting rabbits..."

Meanwhile back in the Serious land of Potty Ash, a more 'insane' hole suddenly appeared in the Russian outback @ 18/11/14: http://rt.com/news/207371-giant-sinkhole-russia-uralkali/  "Before the giant hole appeared near the town of Solikamsk, the company, which is Russia's biggest potash miner, evacuated workers at the Solikamsk-2 mine, due to the inflow of saline water. Operations at the site have been halted, and the level of underground water is being monitored." Locals were told not to worry about it ...  every time I start 'sinking'  https://www.youtube.com/watch?v=GuzO6s9eNWk

But, the significance of this 'event' and potential impacts have been reverberating - http://www.mining.com/insane-pictures-of-russian-potash-mine-disaster-96...

Reasons for the sink hole? "Potentially, fresh water could mix with the brine in a flooded mine, which in turn may create microfractures in a concrete wall by that time.
Tectonic fractures are other possible way water/brine mix may penetrate and dissolve protective pillar. Theoretically, this process may take years, if it really happens.
We will continue to monitor Uralkali’s official statements in this regard"

So what has this got to do with us? Well, firstly the method of brine solution mining is of interest, does anyone use that around here?  https://www.youtube.com/watch?v=GVrjTcwNxQA cough, http://www.mining-technology.com/projects/boulby/ - However the BGS report " Modern methods of underground solution and rocksalt mining do not cause subsidence and only raise modest planning issues at surface. Pumping of natural brine is unlikely to be permitted in future, although some old permissions are still in operation and there is still a legacy of subsidence from historic working by this method."  Methods of Boulby's mining can also be found on their Environmental Impact Statement http://planning.northyorkmoors.org.uk/MVM.DMS/Planning%20Application/808...

And,  secondly, the giant sink hole lies next to one of the worlds largest potash producers, 3% of world market, and production has ceased until further investigations and the mine is made safe.   This impacts on the commodity price of potash, and as world demand grows price for potash is expected to take an upward trend;  source: http://www.stockhouse.com/companies/bullboard/t.icp/ic-potash-corp?posti...

copied here in full in case it vanishes:  "Posted on November 19, 2014 by Alessandro Bruno - sinkholeRussian fertilizer giant Uralkali (LI: URKA), just a year after shaking the potash market by terminating its strategic pricing alliance (BPC) with the Belarusian potash concern Belaruskali announced that it has been struggling with a temporary closure of a major mine, Solikamsk-2, located near Perm. Should the problem turn out to be a long term or even permanent failure there is the risk that the Russian potash producer will incur significant losses. Of course, this could benefit the competition and cause a significant price hike in the price of the popular mineral fertilizer. The mine affected by the shutdown is of considerable importance for Uralkali, covering a fifth of the company’s capacity. On Tuesday, production at Solikamsk was stopped after high levels of brine were discovered. Water dissolves the potash salts (potassium-laden salts) damaging a mine’s structure and causing sinkholes. This is not unusual for Uralkali, but this time the scale of the problem has been more severe than usual. In 2006, Uralkali suffered a similar incident in the same region and the closure lasted a very long time causing a 5% drop in production (but not as great a financial loss, given that potash prices were typically below USD$ 200/ton then).