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Cheap Bulk Eraser for Hard Disks?
cute-boy asks: "Recently I had to replace some hard disk drives from the same batch which had failed, while still under warranty. Because the drives were no longer recognized by the SCSI controller, it was not possible to erase the data on them. In view of the sensitivity of the data contained upon them, and the chance this was still forensically recoverable, our company decided to buy new drives rather than risk the disclosure of their contents by returning then to the supplier. How would you non-destructively (physically) destroy data on a hard disk without access to a bulk eraser? Obviously in this case it's a bit late to be thinking of using encryption."
Why are you against physical destruction? Let your IT department have a field trip to an abadoned parking lot with some sledge hammers.
Open the hard drive (get some Torx T-7 through T-9 bits first, you'll probably need them), pull the platters, and sand them.
Ecce potestas casei!
The poster seems to indicate that the drive has failed and it's impossible to write to it via the normal scsi interface. At that point, the only way to render the data unrecoverable is the physically destroy the platters.
I like taking the drives apart for the magnets, then using heat on the platters...
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...and they can be quite fun... I guess your only option is to open up the new drives, swap the platters, and erase the data that way. Then swap the platters again if you wish so that they're (technically) new again.
Never tried it myself, though everyone on the intrawebs largely agrees that there are legions of the mighty dust army waiting breathlessly for you to crack open the drive so that they can invade it. There is apparently no invention of man capable of withstanding their attack, meaning a high possibility that if you perform this operation and then plug the drive back in, a single dust atom will be all that is needed to whir around frantically in the formerly pristine environment, loosing the veritable fires of Hades on your poor machine until it erupts in a wild, flaming mess, sending shards of platter in all directions to seek the soft flesh of babes and women.
So yeah, they don't recommend doing that.
http://www.semshred.com/content291.html
Ecce potestas casei!
-dave
http://millionnumbers.com/ - own the number of your dreams
Also depending on who your vendors are, you can usually upgrade your service so that you do not need to send back failed disks. Dell for instance has this as part of one of there higher level support contracts.
We were all warned a long time ago that MS products sucked, remember the Magic 8 Ball said, "Outlook not so good"
I've heard that most HD manufacturers understand this common problem, and will allow you to remove and return only the top cover (with the complete model/serial number sticker still entact) of each failed drive as proof that it was destroyed. You should ask about this when requesting an RMA number for your batch of dead drives.
The post clearly states that the drives aren't recognised by the SCSI controller. No mater what OS you use, you won't be able to write on drives if you can't see them.
Either the parent is incapable of reading or is exibiting flaming fan-boyism. In any case, please mod down!
Your drive does not work in such a way that you cannot control the head. Therefore, as you well know, you cannot erase it. What the fuck do you want Slashdot to tell you -- that fairy tales are true?
Oh, and your title is very misleading.
That some companies have a deal with the hard disk manufacturer that they'll ship only the drive's cover when it fails, and destroy the rest. Not 100% sure if this is possible, but if your reason for wanting to wipe the drives is getting a warranty replacement, you might want to consider that.
Otherwise, use thermite, and lots of it. It's cheap and fun.
It is hard for me to believe that no one posting has yet understood the question. The issue is that the querent has failed piece of hardware, under warranty, but doesn't want to return it for replacement fear that the data could be recovered by a highly motivated party.
The answer seems clear. Even if you hard a piece of equipment to erase a drive's contents, you would not be able to verify that the erasure has occurred without the drive functioning in the first place. Therefore, there is unlikely to be a satisfactory solution.
Perhaps you would be better served by writing data to the drives in an encrypted form. Thus, after a future failure, under warranty or not, you could be confident that data recovery would be unlikely.
Magnets! They might bend the heads and scratch the surface, making if that is what you cann 'non-destructive', but it always works. And no refrigerator magnets, obviously.
Wonder what the public key field is for?
Had a similar problem where 1 of 2 hard drives (same model) failed. I switched the logic board out of the good one, used it to replace the dead one, reformatted/overwrote to my heart's content, then switched the logic board back to my good drive.
Make friends with someone who has access to a tire shredder. The shredder will make quick work of the drive and you can then burn the remains for added security or pass them directly to a local recycler (most cities frown upon throwing computer materials in the trash as they usually contain heavy metals). Another option would involve fun with thermite but, that may involve a bit more risk than you are willing to take.
As emphasized in other comments the only way to truly erase a hard drive is to destroy it.
My favorite method involves and magnetic induction burner or hotplate. The benefit of this is it will destroy the data but leave no external trace.
IIRC, the magnetic coercivity of modern hard disk media is sufficiently high that the only sure method of data destruction is physical destruction of the platters.
Sledgehammer in the parking lot on the platters (removed from the drive, if possible) should do nicely for any application short of national security secrets - just be sure to wear safety goggles.
-Isaac
I am not a lawyer, and this is not legal advice. For Entertainment Purposes Only.
I just modded down 4 people in this article, which out of the couple years I've been getting mod points probably doubles the number of posts I've modded down.
THE POSTER ISN'T ASKING FOR METHODS TO DESTROY THE PHYSICAL DISK -- in fact, he specifically says that he does NOT want such methods. What he wants is ways to destroy the DATA without destroying the DISK so that he can return it to the vendor for warranty replacement.
Thus everyone saying "destroy it with thermite", "find someone with a tire shredder", etc. IS OFF TOPIC. (Despite me modding them redundant, off topic would be better.)
Maxtor, Western Digital, and Hitachi all replaced drives that we'd sold into sensitive environments with little fuss. Hitachi needed a signed form faxed back, Maxtor & Western Digital needed the top cover of the drive.
Fellowship 9/11
If you do decide to go down the destructive disposal route you could do what the Aussie department of defence does. 1. Get a big grinding wheel 2. Push harddrives against grinding wheel and collect dust 3. Mix dust with concrete 4. Build a building with said concrete
The most painful way, but only sure way to accomplish this is to disassemble the drive and melt the platters. If they are really old drives, then waving the disassembled platters under a wand-based degausser usually works. This stuff is all measured in oersteds. The recording head has to overcome the coercivity of the magnetic media in order to record a reliable signal. Coercivity is the strength of magnetic field (measured in, you guessed it, oersteds) required to alter the alignment of the particles on the platter. The heads can write at this strength and so must you if you wish to properly erase the data. That's why the big bulk erasers cost so much. The big one, the TD-1 can do up to about 8000 oersteds, which will do anything up to, but not including the perpendicular recording stuff in the 500+GB drives.
If you're a cheap skate, you and a T-8 wrench are going to be friends (get a bit for about every 20 drives cause they wear out fast if you're in a hurry) and pull the drives completely apart, down to getting the platters off the spindle motor. Some drives take a T-10 or T-6. Then send the platters to be burned. If you don't courier them to the incinerator, then at least play 52 card pickup with them and make it difficult for any but the most determined.
When I wored at a knife factory we had a degausing table.
It was THE COOLEST THING. You would place anything with iron and/or magnets on it, turn it on (don't wear a watch) and all magnetism is gone with in about 2 feet.
Highly recognizable keyword(s) + question mark = highly qualified answers from first posters who never made it past the first sentence.
What kind of BOFH are you?
Asking for recommendations for a BULK ERASER? Absurd!
This should have been covered in Lusers 101!
Registered Linux user #421033
Wow.
to the pertinent question.
There is probably no such thing as a cheap and effective bulk eraser. We have an agreement with Maxtor (now Seagate) that allows us to send in the chassis for a replacement, minus the platters. The replacement contract is expensive, though, but we need it since we have a LOT of banking data.
--- Grow a pair, liberals... stop letting the Republicans bully you!
And explain your concerns. Some manufacturers have a policy where you only return part of a drive (usually the cover) if you don't want your sensitive data to be transported.
.22 from a rifle will work as well, but you'll need to put a dozen rounds through it.
Once you get the replacement drives, take them to the range and fill them with bullet holes. A 2 3/4" 12 gauge slug should take out a quarter of the drive at a time. Or fill with 9mm holes - when hit, the platter around the entry hole gets pulled out.
A
If you hit the drive on the edge dead center with an 8mm, the drive should be able to stop the bullet, which transfers a lot of energy to the case and sends the drive flying 50+ feet down range.
Tons of fun. Much faster and easier than sledge hammers.
1q2w3e4r5t6y7u8i9o0pqawsedrftgthyjukilo;p'azsxdcf
Actually, drives aren't hermetically sealed, so that might not do as much as you hope.
Well, the statement "it was not possible to erase the data on them" directly contradicts the possibility of an answer the question of how to "non-destructively (physically) destroy data on a hard disk without access to a bulk eraser", unless of course, your current limitations include the magical exception of having access to some really fun electronics equipment.
Then again, I'm still wondering WTF the term "bulk eraser" is supposed to mean.
A useful starting point would be reading Secure Deletion of Data from Magnetic and Solid-State Memory. A quick Google search also came up with this tidbit concerning NTFS file systems.
First, I don't think that bulk-erasing counts as non-destructive today. Not all drives can do servo writing without additional equipment.
Second, I don't think you can get bulk erasers that work for modern harddrives. The magnetic fiel strenght may just be too large.
Advice: Do physical destruction and live with the financial loss. Acting first and thinking later has a price. Please pay it.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
1. If the drive is no longer recognized by the controller then the circuitry on the board has been damaged. Replace the board from an identical drive and you may be able to access it again.
2. If your data is so sensitive that you can't risk sending it back then that risk is far more than the cost of the drive. Physically destroy it and buy some other brand to replace it.
3. Its doubtful that degaussers (as suggested elsewhere in the responses) would work. The platters are encases in relatively think metal which will block the field and if you've ever opened a dead drive then you know that the platters already resist the relatively powerful magenet used to control the drive heads.
4. Do your drives have enough airflow past them to keep them cool? 90% of cases from name-brand manufacturers do not. Dell, for example, is one of the worst offendors. If the drives are hot to the touch just after you power down the machine then the replacement drive is going to burn out too.
Moderating "-1, Disagree" is simple censorship. Have the guts to post your opinion.
The only solution is Kompressor Krushing your disks.
I am working for a company with a similar problem. All our really high security clients request to have the data destroyed with no chance of recovery (incineration). for the clients who wish to recover the drives and reuse or sell them our warehouse uses some apps that write random data over the disks about 30 or so times to make sure that the data is fully erased. Can't think of the software they use (Im an onsite tech and they only use the software in the disposal warehouse) but a quick google search would come up with something.
The secure delete is the only non-destructive method I have heard of but I think that some feel that the data is not totally gone (just very very very hard to recover).
They are not hermetically sealed, but they are sealed against dust, so yeah, opening it will fuck it up pretty fast. But it will run for 20-30 minutes before it craps out.
If your vendor is reputable, your data will be destroyed from the disks you send back... either wholesale drive destruction, platter destruction, or platter degaussing. I don't know what happens with other vendors besides IBM, Sun and HP, and hope to never have to find out.
Next time you go to the doctor, ask for an MRI, bill it to insurance, and take the drive in with you. :-) Profit!
Actually Martha Stewart had a household hint for wiping drives,say with sensitive stock info,for instance.
1.dismantle drives,remove and seperate disks.
2.place disks on no slip padding and use a finishing sander with a variety of metalgrade sandpapers to wipe the data gently from the disks.
3.Sip sherry till youre silly and do speedballs off the butlers apparatus.
*Repent!Quit Your Job!Slack Off!The World Ends Tomorrow and You May Die!
If you're a big enough customer, or the vendor is understanding, perhaps you can arrange for them to inspect the drives under your supervision and confirm that they are no good. Then take them, accompanied by the vendor's representative if they want to be sure you destroy them, and drop them into the vat at your local steel mill, or whatever less dramatic method of physical destruction works for you.
the drives were no longer recognized by the SCSI controller,
A problem with the SCSI controller, or with the drive's on-board electronics?
If the former, just replace the controller. Check this by moving the drives to a box with a working controller.
If the problem is the on-board drive electronics, then using a working drive of the exact same make and model, carefully undo the 3 or 4 screws holding the circuit board to the drive and swap the board from the good drive with the board from the bad drive. If this was the problem you should now be able to access the data on the old drive.
I've done this with a Seagate Barracuda that had its electronics fried because of a catastrophic power supply failure (detonated one of the chips and vaporized a couple of circuit traces). Swapping the board from an identical drive (I had a bunch around) let me recover the data. Not knowing the condition of any circuitry within the drive itself, I retired the drive after copying off the data. I would have erased it too but I was planning on disassembling it anyway.
(NB - even the same make an model number doesn't guarantee interchangable parts -- I had a similar problem with a Western Digital 80GB drive that I didn't happen to have a duplicate of, although that model was still on the market. Alas there's another 4-character code after the model number (ie, the "real" model number, except you need to see the faceplate to find it out) and in the year or so since buying the first one, there were enough minor changes that the circuit boards weren't interchangeable.)
-- Alastair
Wrap 200 feet of wire around them one at a time and connect it to a car battery for a couple seconds. Or just buy some super powered, non-electric magnets like those natural earth magnet thingies from mythbusters. Eh, a stack of walmart ones would probably do it if you stuck them all over drive. I bet if you just plain touched two live wires to the drives, they'd never spin again. Speaking of that, just open them and take the read/write head out. You can also bring them all to the local doctor and blast them with an X-ray machine, I heard that works. If you dipped them in warm lemon juice and they weren't air tight (don't think they are) they'd oxidize all the metals on the inside and make it unreadable but I think they might suspect that's what broke them. Oh and also, MRI scans will probably work too if the X-ray machine is busy. Your local custruction company or junk yard should have one of those magnetic lifter cranes that lifts scrap metal and they might let you stick the drives on there. Hehehe they're using one on a show on TV right now...anyway, one of them should work, have fun.
now stop reading and go play Dance Dance Revolution!
Besides....this'll void the warranty on the new drives, also, so you'll be potentially doubling the wasted expenditure of if you'd just destroyed the original failed drives in the first place.
"City hall" in German is "Rathaus" Kinda explains a few things......
Oh come on now. How much does a SCSI drive cost? $200.00? $500.00? $75.00? If your data is so sensitive that you're worried about it being reconstructed by the RMA people, then just destroy the drive and kiss the warranty replacement goodbye. Seventy five dollars is not that much of a cost to bear to ensure that your data is safe.
When our name is on the back of your car, we're behind you all the way!
This won't help so much this time, but if the disks were encrypted with a strong password - you only have to enter it when the system is booted, and for a server this shouldn't be too often - then you could send back the disc without the manufacturer being able to read the data.
Unfortunately, it is not possible to bulk erase modern hard disk platters. You would need a degauser that is so powerful, that it will physically destroy the platters anyway - bend them - and you will end up with one heck of a electricity bill. Therefore, you can just as well do away with the magnetics and destroy them physically with a big hammer.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Yes, of course.
Does nobody pay attention to ANYTHING anymore?
Paranoid nutballs claim that data can somehow be miraculously recovered after multiple overwrites by random data, but even Jesus, the CIA, NSA and George Bush together couldn't do that.
One magazine load (10 rounds) about $2. One destroyed disk drive, priceless.
Fun too. They bounce around pretty nicely.
Of course, if you want to send it for warranty exchange, the manufacturer probably wouldn't appreciate yoru marksmanship. But if the alternative is to keep them forever so no one else can try to recover the data, I'd say go for the AR-15.
Or M-1 Garand. Or any other reasonable facsimile.
Infuriate left and right
50-100oz magnet and sit it on top of the hard disk. Like the kind you find on the back of PA woofers. It's worked for me :)
On the other hand, I knew an old hardware hacker running a small computer shop in rural NC... customers would bring in failed drives, if he could determine the failure was on the controller, he would find a spare drive with the same model number and swap out the controllers - revived the drive with data intact.
Not sure if it's possible / easy to do that with these particular drives, but it's worth looking into...
I am disrespectful to dirt! Can you see that I am serious?!
There might be a better way of doing this, but the *old* way was to just use low level format software. The typical procedure is you
1. go to the hard drive manufacturer's website
2. download their "utilities" package
3. prepare a DOS-bootable floppy with the utilities on it
4. invoke the low-level format software (IMPORTANT: You want a LOW LEVEL format. Just typing "format" or something in DOS will not do the trick.)
This will work 100%. What it does is overwrite every byte on every sector to a blank ("00" I believe...). There's no file system footprint, no echo or memory of what was once on the drive. There is nothing to recover, because *everything* has been overwritten with a null value.
The downside? It takes a long time, especially if you're drive is well over the 100 gig variety. But it will get the job done. Cheers!
I bought a lot of 10 identical 40 gig laptop drives from an eBay seller for some teeny pittance (I want to say something like $10 shipped) that were explicitly sold as non-working. Of the bunch, most of them didn't do a thing. However, there were 2 that had some broken pins, and a few that read fine but had massive data errors. I had no trouble swapping the controller boards from the ones with broken pins from one of the data error ones and ended up with 2 good 40 gig drives for $10. Wasn't too shabby I thought.
Go to the local park one day when they're trimming the trees. Just take all of the HDDs and throw them into the big chipper/shreader thing that they have there. Voila, no more HDDs to worry about.
So these were working drives, got pulled due to a recall, but somehow can't be accessed? And if you aren't RMAing, why not physically destroy? Or at least get a car battery electromagnet, a couple temps (you just flush 'em when you're done) and a weekend? Or would that still be "forensically recoverable"? If so, then just bury them. (In whichever largest body of water is closest...)
Shift happens. Fire it up.
We've seen lots of stuff put it there, how about you try it with a hard drive? :-D
This sounds so redundant...
Anagram("United States of America") == "Dine out, taste a Mac, fries"
I've also done this a long time ago, it works!!! then you can run a DOD erase x4!!! Part of my job a CDC was to do this....
Stan M. ~~~Verbal~~~
Dude... classic!!!
Stan M. ~~~Verbal~~~
Should only take you about ten minutes per drive to do this. All you need is one of those special screwdrivers.
PS: Do it in a recently vacuumed room - if dust/hairs get in the drive it can be detrimental.
No sig today...
A good source for magnetometers and demagnetizers that really work.
I first ran across them when doing audo work with large tape recorders
and needed to demagnetize the hardened steel tape guides and capstans.
The inexpensive units sold in the stereo and electronics stores were not
strong enough to do the job. R B Annis magnetometers let me measure
the amount of megnetization and their Han-D-Mag demagnetizer let
me demagnetize the hardened steel components easialy. The Hand-D-
Mag will also easily demagnetize 1/2 inch rolls of tape or greater with
the back side of the probe!
http://www.rbannis.com/
Sad to say, but if you can't run the drive to erase the data, you MUST destroy the platters. Even degaussing them is not reliable -- how will you KNOW the degauss worked? Unless you want to keep a spare drive of each model around with an open top so you can swap in and reformat platters from dead drives (way too much trouble), you're stuck with physical destruction.
So, in keeping the military standards for such things, I suggest you find a way to render the platters unspinnable without creating too mush hazardous waste. Thermite or other pyrotechnics are regrettably messy and pose a fire hazard in use, aside from the regulatory headaches. Acids create too much dangerous waste. Having the platters -- or just the whole drive -- crushed or cut up with a hydraulic shear or press of some sort is likely the best candidate.
Punching the spindles right out of the drives with 10 tons of force from a hydraulic press at a local garage or machine shop will definitely render the platters warped and unreadable, and is likely the best and simplest way to do the deed. Punch a second big hole through one side of the platters, and the Devil himself would be hard put to recover anything from the drives.
"My strength is as the strength of ten men, for I am wired to the eyeballs on espresso."
You may actually be able to do the job with common office or household equipment. If you work at a hospital or clinic, for example, try running them through the MRI. Not only will the data not be forensically recoverable, but the disk should be sufficiently bent so as to discourage any attempt regardless. Also works well with floppy disks, VHS tapes, and metalheads.
Technically of course you are correct, but I've tried it.
Years ago I had a Seagate ST-whatever SCSI drive, one of the ones with the stiction problem. I backed it up as soon as I started having problems and wanted to see how long it would last. I took it out of the case and ran it sitting on the desk. It worked fine until I turned it off but had to whack it on the side with a screwdriver handle to get it going again.
Fast forward a few months and even that didn't work so I popped the cover off and got it started with my finger on the side of the platter. That worked until I got tired of the whole thing so I put a tiny drop of WD-40 on the spindle. That's when I started getting read errors. My conclusion? WD-40 erases hard drives.
BTW, others have said it but don't toss those old drives without snarfing the magnets out of them. They make the worlds greatest fridge magnets or are handy for sicking stuff to the side of your tool box. 1001 uses.
Your bottom line best bet is on physical destruction. In my case I had to do this "in the field" which severely limits your methodologies that you can deploy. Just try bringing caustic acids on an airplane these days! Or shipping huge degaussing equipment. Besides that, in my case it had to be done on site, and then you have to contend with their security personnel as well. The answer to my problem was a $20 battery powered Dremel tool and an abrasive rubberized pad. No problems with 110,120,220,240, 50 or 60 Hz power issues. You can pick one of these up cheaply sold as a "pumpkin carver" tool in Oct if you don't mind a bright orange casing.
For the actual destruction it takes about five minutes to disassemble a disk drive, and about 15 minutes per platter to make it unrecoverable. Contrast this to wiping or the expense of degaussing. Given that the larger the capacity disk the longer the wipe time, the cheap Dremel is a lot faster! The expense of the degausing equipment is a large investment in contrast with the $20 Dremel, and there is no contest even when factoring in the pay scale of the person performing the destruction. The only issue I had on site was that the newer laptops use glass platters which take too long to "polish" the magnetic surface and were prone to break in the process, but they can be reduced to sand in a matter of seconds with it folded in a common everyday news paper and even your cheapest hammer.
Bottom line, your inexpensive path is sometimes still the best!
My understanding is only AC electromagnets are suitable for degaussing. It would take a large AC magnet to be sure of degaussing a hard drive completely. I don't think the small ones intended for degaussing CRT TV's would be effective. You would need one intended for the application.
Degaussing works by exposing the magnetic target to very strong fields. This makes everything follow the field of the electromagnet. Slowly the electromagnetic field intensity is reduced until you are left with essentially random fields. These random fields cancel each other out leaving no net magnetic moment. As gauss = magnetic field, no net magnetic field = degauss. Hence the term "Degauss".
Remember how sysadmins used to have head-crash-scratched disk platters as wall decoration? She had one that was shiny clean metal, with not a trace of magnetic media left :-)
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
The company I work for contracted with our offsite media vault vendor. They incinerated a few thousand backup tapes we didn't need anymore. Bonded and insured... and they let a rep from our company witness it.
I had my disk drive laid against a hillside across from my front door, 75% slope or so ... it sometimes slid around, sometimes jumped a few feet in the air, and being only 100 feet away, it was easy to go pick it up if it moved too far.
Infuriate left and right
A problem with the SCSI controller, or with the drive's on-board electronics?
If the former, just replace the controller. Check this by moving the drives to a box with a working controller.
Don't overlook the possibility an employee may have lifted the terminator. I've seen where this is overlooked when drives stop working in a SCSI environment.
The truth shall set you free!
Data recovery companies can fix the logic boards too. I would imagine that the poster would be concerned about data recovery companies seeing the data also though.
Another idea is to cook the drives. Heating a drive in an oven should give the data a good scramble. I'm guessing it is probably better than a degausser considering some of the comments here.
Ummm, Jon, aren't you supposed to be dead...? - Otter(3800)
Yeah. I almost mentioned that (and just checking termination in general) but figured "nah, that's so obvious he has to have checked it first". But you have a point, some things are so obvious that they are overlooked.
("Did you check that it was plugged in?" "Don't be silly, of course I ch... Oh, oops.")
-- Alastair
If the data is life-or-death stuff incineration is the only way to go. In the army we used white phosphorus grenades for expedient destruction. You could probably get a civilian pyro expert to do it with thermite.
If the sensitivity has a fixed (and reasonably short) duration secure storage may be your best bet. Could be as simple as, say, putting it in a cabinet in the server room for a year, by which time the patent application will be filed and you can just tip the drive.
The most likely scenario is that you need to dispose of them diligently, and the material is sensitive but not Earth shattering. In this case by FAR the easiest means is the good 'ol drill press. Knocking a couple of holes through the logic board and platters will make the drive resistant to most "conventional" methods of recovery. This method is NOT proof against the NSA's best efforts or whatever, but it is unlikely that your information really requires more sophisticated protection than this.
Good luck.
-Peter
I recently got rid of some very OLD equipment. I had some old hard drive that predated me by 15 years. They were huge and I had no idea what was on them. They weren't IDE or MFM. They came from the day that hard drives required an external controller card. Since I needed to wipe anything that left the building I didn't have many options. I did what my predecessor and his predecessor had done.
I left the drives sitting in a cabinet where they had sat for the last 2+ decades.
Since you don't need to send the drives back to the manufacturter and you just need to be sure no one else can get the data, why don't you just sit on the drives? If they sit there for 10-20 years then even if the data were to get out in the wild it would likely be 100% useless anyway.
Ninjas don't carry tic tacs