The general public are advised against trying to salvage any of the debris that washes ashore.
"I feel for everybody that's currently at Waihi Beach," said Mr Brownlee.
"It would be great if New Zealand could have a really clean run in 2012."
Waihi Beach reopened to the public this afternoon after earlier being closed.
About 300 containers have fallen off the ship in the days since it split.
Waihi Beach Community Board Member Derek Mills said the beach is covered with polystyrene foam and various packets from inside the containers.
He said there was at least one 44-gallon drum rolling in the surf, and he could see at least three containers floating in the sea.
Mr Mills said looking further south he can see another three containers sitting on the beach.
Police had received calls about the occupants of a vehicle taking bags of what appeared to be milk powder this morning before driving off.
Members of the public are advised not to approach items washed ashore for health reasons.
The Bay of Plenty Regional Council is holding off before it expands the exclusion zone around the Rena.
The existing exclusion zone is in place three nautical miles around the wreck, but the ocean's now littered with containers and debris extending many more miles.
Council's head of water Eddie Grogan says they're waiting to get more information before they officially expand the exclusion zone.
"As the weather changes, the area affected changes so we've had a shift in wind which is now bringing the debris on shore so had we changed the size of it yesterday we'd be having to change it again today.''
Mr Grogan says boaties should avoid heading onto the water, but if they need to they should take extreme care.
Meanwhile salvors say it's too early to what the future of the Rena salvage operation will entail.
The ship is in two distinct pieces on the Astrolabe Reef, with the front section rested firmly on the reef, and the stern moving about significantly.
Svitzer Salvage spokesman Matt Watson said salvors are trying to work out if they can resume container removal operations.
"It's too dangerous at the moment, it is a very real possibility that rear section could slip off the reef and sink, we just have to wait for the swel and the weather to calm down a bit.''
Mr Watson says if they can't get the crane barge up close to the Rena, they may be able to use a long crane and pull containers off from a distance.
Public warned to steer clear
Earlier today, Maritime New Zealand and police closed access to Waihi Beach.
Sergeant Dave Litton of Waihi Police said there had been reports of people taking bags of what appeared to be milk powder before driving off.
He said four containers had washed ashore this morning and several more were likely to make landfall as the day progresses.
"For that reason and because we don't know the contents of the containers, we are urging members of the public to stay away from the beach.
"The expert advice we have received is for people not to approach items washed ashore for health reasons and we appeal to those people who have taken objects to return them to the beach where they can be managed by decontamination crews."
Containers, milk powder and polystyrene debris were found at the beach, 60 kilometres north of the split ship's grounding point near Tauranga.
Fire Brigade volunteers have been clearing away people who had been coming onto the beach to take pictures, though most were respecting calls to stay away from the debris.
The Bay of Plenty Regional Council is advising boaties to stay off the water in the affected area. The harbour master has established a cautionary area along the western Bay of Plenty, stretching from Waihi Beach to Maketu, where boaties should navigate "with extreme caution", keeping a lookout for debris and travelling through the area only in daylight.
The council said the region's beaches have not been closed, however swimmers are also advised to stay out of the water.
Container recovery specialist Grant Dyson said buoys have been attached to 45 containers this morning. There are a number of anchorage points out at sea.
Dyson said debris was starting to wash onto Mt Maunganui and Papamoa beaches - mainly insulation and timber.
'Hundreds and hundreds' of bags
Waihi Leader editor Fritha Tagg was at the scene this morning.
"The beach is littered with polystyrene and there are lots of people on the beach looking,'' she said. "It runs from about the middle of the beach north.''
Further along the beach there were "hundreds and hundreds of bags'' of milk powder strewn into large piles.
"You can actually smell the milk powder but it is still powder, the bags must be well sealed.''
Ms Tagg said she could see another container in the ocean that appeared to have milk powder inside.
Meanwhile, Maketu and Eastern Bay residents are waiting to see if any debris or oil from the Rena also washes up on their beaches.
While the exact path of the debris and oil is not yet known, Maketu locals hope they are not in for another big clean-up.
Thornton Beach maritime expert George Johnston said existing sea currents would send debris to Maketu, which was badly hit by oil when the Rena grounded off the coast in October.
"Over the years everything, from wrecked boats to bodies, either ends up near Motiti or further down the East Coast.
"If anything in the water heads toward the East Coast, it generally passes between Whale and White islands and keeps going down.''
Bay of Plenty Regional Council community relations manager Bronwyn Campbell said the containers and cargo in the water were currently going north but a wind change was expected, although that alone would not determine where they went.
A cautionary area around the Rena includes from Waihi Beach to Mayor Island to Maketu and boaties are urged to navigate with extreme caution, travel at slow speeds, keep a good lookout and to stay off the water at night.
Ms Campbell said the debris field was extensive and its movement was unpredictable and could extend further.
Maritime New Zealand said another seven containers were known to be within a mile of the Waihi shore, and container recovery company Braemar Howells was using tug boats to tow them.
Teams were already on Waihi Beach to secure and start removing the debris, with another investigating unconfirmed reports of a container ashore just inside the Bowentown entrance.
Witnesses: containers heading north
Sam Anderson said he was walking his dog at 6.30am when he saw around 200-300 packets of milk powder washed ashore at the beach, as well as "three really bashed-up containers" in the water.
Mr Anderson said he didn't see any clean-up crew members on the beach, where a strong odour was in the air.
Residents Pam and Dave told nzherald.co.nz the debris and containers were floating off the north end of the beach, and appeared to heading north up the Coromandel Peninsula.
Waihi Beach Surf Lifesaving Club head guard Daniel Peacocke said there are about five containers on the beach at the moment and another half dozen in the water.
Mr Peacock said it had been a quiet summer so far for the club's crew, until today.
"There's quite a few people hanging around here that we are just trying to keep off the beach."
Waihi Beach Community Board member Derek Mills told the Bay of Plenty Times there were four containers already on the beach.
"One of them is broken up and there's something that looks like milk powder, Mr Mills said.
"There's a great heap of that on the beach."
Mr Mills was on the beach at 6am and said it looked as though the containers at sea were travelling north.
"That's what is scaring me because if they crash into the rocks at Coromandel and start banging into those rocks ... it's a bit of a shock I guess. We thought we were a bit bulletproof because last time it missed us and headed towards Maketu."
A spokeswoman for Maritime New Zealand confirmed representatives for Braemar Howells were sent to the beach today to put in security measures as some of the debris could be hazardous.
Maritime New Zealand said it was important no one touched any debris or containers, which are believed to contain milk powder, timber, plastics and furniture.
At Mount Maunganui, Jacinta Fitzgerald reported seeing "foam and scum" and possibly oil washed ashore north of Tay Street.
A hotline has been set up to report anything washed ashore. Phone 0800 333 771 or 027 897 4259.
Black tide "unlikely"
Environment Minister Nick Smith says it's unlikely there will be a repeat of the black tides that closed a number of Bay of Plenty beaches last year.
The aching wreck of the Greek-owned ship, which crashed into Astrolabe Reef off the coast of Tauranga on October 5, finally relented on Saturday night with a six-metre swell breaking it in two and tossing up to 300 containers overboard.
There is now a yawning 20 to 30 metre gap between the ship's bow and stern section, which is listing at 23 degrees to starboard and is likely to sink.
Maritime New Zealand said there has been no significant changes to the position and condition of the vessel overnight.
An observational flight this morning will gather more information about the status of the Rena, as well as to observe where lost containers have scattered and whether anymore oil has leaked from the vessel.
Environment Minister Nick Smith said the latest development in New Zealand's worst environmental disaster was "serious but not unexpected" as maritime officials had predicted a big swell was likely to break the vessel apart.
"It was simply a matter of time before there would be a storm event of sufficient magnitude to break the vessel in two and what has transpired in the last 24 hours is very much expected," said Mr Smith.
He said things had improved from an environmental perspective with the removal of the bulk of the 1300 tonnes of oil on board which means "the risks for the environment are a fraction of what they were in October".
"It is possible that there will be releases of oil but they will be in the order of tens of tonnes and not hundreds of tonnes and those things are unlikely to result in any beach closures."
Mr Smith said the bow section of the vessel was firmly wedged on the reef and would probably not shift but the stern was "likely to sink at some stage" and recovery of the containers on it had become problematic.
"Certainly it is true that the potential for recovery of containers on the stern section of the vessel has now become an order of magnitude more difficult given the extent of the damage to the ship."
Response teams mobilised
National On Scene Commander Alex van Wijngaarden said response teams including wildlife experts and defence forces had been mobilised.
He said trajectory modelling predicted any oil released from the ship was to have come ashore early this morning, landing on beaches south east of Mt Maunganui but this was weather-dependent.
Maritime New Zealand salvage unit manager David Billington said officials yesterday found the ship with many of its hatch covers broken and containers thrown into the sea.
He said salvors were working to assess its state so naval architects could undertake further calculations to get a clearer picture of its ongoing stability.
Mr Billington said more containers were likely to be lost.
Claudine Sharp of recovery company Braemar Howells said of the 837 containers on the ship before the weekend storm between 200 and 300 had been washed overboard.
Of those, between 20 and 30 per cent had been fitted with transponders and around 30 containers had already been found. Ms Sharp said just 20 per cent of the containers would float, the rest would sink.
Shipping lines to Tauranga harbour remain open but the three-nautical-mile exclusion zone around the Rena remains in place.
Ms Sharp said the company was working closely with the harbour master and had been doing sonar sweeps of the harbour entrance for invisible containers.
She said trajectory models showed containers and debris heading in a northwest direction, probably towards Waihi. The debris is likely to wash ashore this afternoon but this was again weather and wind dependent.
"Our plan is to corral them and recover them promptly."
Tauranga mayor Stuart Crosby said the inclement weather had kept people off the beaches.
He said people needed to leave debris washed ashore to the response teams.
"Kiwis are inquisitive by nature and I'm sure there will be a lot of people on the beaches looking for debris. The main thing is ... they don't touch it.
"The key issue has always been the oil, what oil that may have ended up on beaches will be very small and will be removed very quickly."
