The 33ft (10m) deep crater appeared eight days ago in Fontmell Close, and nearly 7,000 tonnes of concrete has been pumped into it.
Hertfordshire County Council has said tests are under way to see if there are any more cavities.
It is unable to say if there has been further movement without looking at the results of that monitoring work.
Dozens of residents have been unable to move back into their homes. Some are angry that a smaller hole reported previously had not been filled in.
"The neighbour whose house it was outside was concerned and was chasing for some action and not getting an awful lot," said David Walker, who lives on the street.
Council spokesman Rob Smith said: "Safety is our priority and we think we are a long way towards achieving that. We need to know what's going on in the surrounding ground.
"We've already started doing non-intrusive radar-type surveys of the road to see if there's anything else that might possibly happen."

The Scot's brother Jamie, Kyle Edmund, Dan Evans and Dom Inglot are in the team for the round-two tie in Belgrade.
Murray, 29, is into the last eight at Wimbledon after beating Nick Kyrgios.
"Both Murrays are still involved at Wimbledon so we'll have to see how it pans out," captain Leon Smith said.
"It's a brutal schedule. To turn around from Wimbledon, fly over to another country and change surface, it's not easy," he told BBC Radio 5 live.
"Our team is extremely passionate about the Davis Cup. Andy wanted to be named in the initial team. He loves the competition. At the moment the most important thing for him is Wimbledon. He has to see how he feels. If he says he can't do this then of course we'll respect it."
Serbia's world number one Novak Djokovic has already announced he will not play.
The 29-year-old admitted he was not 100% fit after he was knocked out of Wimbledon in the third round by American Sam Querrey.
Viktor Troicki, who is ranked 27 in the world, has also made himself unavailable for Serbia, who will be relying on Dusan Lajovic (82) as their only player inside the world's top 100.
Also selected are Filip Krajinovic (108) and Janko Tipsarevic (411). Nenad Zimonjic will play doubles.
The winners of the match will face either Italy or Argentina in the semi-finals in September.
Britain are the Davis Cup holders, having won the event last year for the first time since 1936.

Front row Faletau, 28, has three caps for his country and will arrive from Championship club Yorkshire Carnegie.
Fellow prop Cosgrove, 22, is a former Scotland Under-20 international who is also eligible to play for England, and will arrive from the Pro12 outfit.
"The Championship has some excellent players and Sione is in his prime," said interim Bristol boss Mark Tainton.
"Both players were impressed that there's a clear understanding about what we want to achieve, and they're eager to be a part of that."
Bristol are bottom of the Premiership, seven points from safety with five games remaining.
Engineers working at the St Albans sinkhole have revealed the ground is still moving and cracks are appearing.
[NEXT_CONCEPT]
Andy Murray is one of five players named by Great Britain for this month's Davis Cup tie with Serbia, although the world number two will not confirm his involvement until after Wimbledon.
[NEXT_CONCEPT]
Bristol have signed Tonga international Sione Faletau and Edinburgh's Jack Cosgrove for next season.