I think it's possible, at least I really want to believe. (I loves me some mill.)

Before coming up with a drafting plan, there's two things we have to consider:

1. How much mill do we need to see in a game to win?
2. What milling cards are available to us in the draft itself?

(1) Mill to Win

In limited your opponent starts with 40 cards. He will draw 7 cards in a starting grip. Assuming the game lasts 9 turns and the opponent draws no additional cards, he will end the game with 24 cards in his library. But this is Zendikar, so we can assume the opponent will take a few additional cards from his or her deck. Lets assume we need to consistently mill 22 cards from the opponent's deck to win with mill.

(2) Mill toolbox

Milling card - Any card that moves cards from the opponent's (OR BOTH) library(ies) to anywhere else. (This definition includes - drawing, RFG'ing, and real 'library to graveyard' milling)

Common

Uncommon

Rare+ - (This cannot be forced or counted on, do not plan on these)

Where Archive Trap could win the game.

So it looks like we have to force a plan of Blue, since we only get two creatures that can do this work. Reckless Scholar isn't anything amazing, but one or two could be handy to find what we need and then afterwards push the mill.

Putting it all together

To mill 22-24 cards reliably, we're going to want to see at least 2 Hedron Crab and 2 Reckless Scholar. To support Hedron Crab we need enough Landfall happening to trigger him 8 times. We need enough control to keep him alive, or get him back on the field should he meet an untimely demise. Finally, we will need enough board control to keep the opponent down while we pursue our alternate win condition.

I recommend a Blue with a Green+Black splash build:

A Rough Pick Order

1. (Mill Bombs - Archive Trap/Sacrament - Not that we expect any)
2. Hedron Crab (Must get two, should take as many as possible.)
3. Landfall Enablers - Harrow, Khalni Heart Expedition, etc etc
4. Recollect for Crabs - Grim Discovery, etc
5. Control - Cancel, Disfigure, Hideous End(?), Into the Roil
6. Blockers - Kraken Hatchling, etc
7. Reckless Scholar
8. Other stuff.

Example implementation

Here's what I just finished drafting. I hit paydirt on pick 4 (Sacrament) then Reckless scholar into hedron on pick 6. Never saw another hedron though.

A friend of mine on his first draft of ZEN made a Milling UG deck. He's got 3 hedron crab, 1 fetchland and 2 harrows. He drafted that not planning on a milling deck but making a "normal" deck with a milling posibility.

Turn 1. Island. Hedron crab. Turn 2. Hedron Crab. Island. Turn 3. Fetchland. Harrow. GG

Turn 2. 6 cards milled. Turn 3. 6+6+12 cards milled. Total 30 cards milled + 7 initial hand + 3 draws. GG

[[Hedron Crab]]

I did, i was lucky with 1 Archive Trap, 2 Hedrons and some control stuff like a Pitfall Trap and the 5 damage divider trap. Turned out to be very funny, i had the Shroud Sfinx as my win mostly. Didnt have a Harrow tho =( I just played blue/white. Ended at #3 of 42.

I think it is possible to build one, but not possible to build one which is going to let you be super effective. Even if you draft the nuts and get 2 hedron crabs and an archive trap, you have 3 dedicated mill cards in the format which do nothing other than mill.

What we all suffer from is looking to the best case scenario, IF I get 2 hedron crabs in my opening hand, IF I get an archive trap AND they have a fetchland, IF I mill a bomb, is just too many ifs. I've been killed by mill once in my Zendikar drafts, and it was because I got mana screwed and my opponent killed me like, turn 7 or 8 with 2 crabs and harrows. The next game he played a hedron crab, milled 6 cards I didn't need, and ended up chumping with it to buy another turn before dying to lethal.

Zendikar draft has the potential to be so explosive that you may never get more than 2 or 3 landfall triggers off before you are dead. The fact of the matter is that unless you have nothing but mill cards in your deck, a mill strategy is just hobbling your win chance. If you're running Aggro with a "mill chance" I'd argue that its a better strategy to leave your mill at home and run 3-4 more aggro options. If you don't draw your "mill hand" your crab/archive traps are not threats or answers.

I haven't done it, but with Hedron Crab and Archive Trap I think it's possible. I got one of each in my sealed pre-release event and had a bit of milling in the first few games. Ultimately it wasn't enough to win the games, but perhaps in a draft it's easier to focus on more milling cards and get a decent milling-landfall deck. You'll need tons of defense to get away with it, though.

EDIT: Sadistic Sacrament could also help here, but it's probably not worth the huge kicker cost just to mill.

Because of Redsai's answer, i thought you guys might be interested about seeing my sealed milling deck from the Prerelease. It's not an intact deck anymore, but i think i know what was in.

Here goes:

// Lands
    1 [ZEN] Kabira Crossroads
    1 [ZEN] Soaring Seacliff
    7 [ZEN] Island 
    7 [ZEN] Plains 

// Creatures
    1 [ZEN] Steppe Lynx
    1 [ZEN] Welkin Tern
    1 [ZEN] Sky Ruin Drake
    1 [ZEN] Sphinx of Jwar Isle
    1 [ZEN] Kor Skyfisher
    2 [ZEN] Hedron Crab
    1 [ZEN] Kor Hookmaster
    1 [ZEN] Shoal Serpent
    2 [ZEN] Kor Duelist
    1 [ZEN] Merfolk Seastalkers

// Spells
    2 [ZEN] Explorer's Scope
    1 [ZEN] Whiplash Trap
    1 [ZEN] Paralyzing Grasp
    1 [ZEN] Adventuring Gear
    1 [ZEN] Trusty Machete
    1 [ZEN] Archive Trap
    1 [ZEN] Day of Judgment
    1 [ZEN] Into the Roil
    2 [ZEN] Journey to Nowhere
    1 [ZEN] Pitfall Trap

Check out this article from Daily Mtg.

its possible, i was defeated by one with two crabs and two archive traps, thoug i lost one game on aggro. These cards could be picked late and become devistating in multiples, but you can;t really plan on getting them and you shouldn't splash for them. if you have a few you picked late they boost up your deck but don't neglect your aggro and removale and bomb picks for them.