DoD Harddrive Secure Erase Wipe

I have a project which I need to DoD harddrives for the company. I
have large raid-scsi enclosure which I can use.

I have access Quad/Octa Xeon P4 servers with 3 dual channel LVE/SE
ultra scsi 160 cards. With these, I would be able to drive 4 x 14 scsi
drive (IBM EXP300 / 3531-1RU) units.

What are my options?

I was thinking about doing following.

1. for i in 1 2 3 4 5 6 7; do time dd /dev/random of=/dev/sda
bs=1048576; done

Use the random bits into drive 7 times.
I think with 14 x 36GB scsi in raid5 setup would take approximately
18 x 7pass = 5 days.
This is pretty bad.

2. I could setup stripped version of gentoo with proper raid
controller driver(here IBM ServeRaid 4Mx and run DBAN from boot drive.

I've got a question, does anyone have working knowledge of DoD5200.28-
STD & DoD5200.22-M? I need to know how it's supposed to work, then I
could just write simple c program to erase drive instead of relying on
other tools for speed.
I need fastest solution available.

Thanks.