The A469 between Pontlottyn and New Tredegar remains closed to traffic.
Ground monitoring by council officers has shown there was no further movement last week, which means work can now be considered at the site to correct the landslip.
In a statement, Caerphilly County Borough Council said: “Drainage designs have progressed and machinery has been on site to excavate trial holes to retrieve data for design purposes. Also, careful excavations will take place at locations which have sunk/cracked to determine if there are other difficulties that will need to be dealt with. These excavation works are subject to gaining Welsh Water agreement and can be weather dependant.
“A site meeting with local councillors, the local AM and others key agencies has taken place to see the difficulties faced and discuss the way forward. Conversation was naturally around how quickly these issues will be resolved so that the road can reopen at the earliest opportunity.
“CCBC is liaising with Welsh Water and we are awaiting their decision about the replacement of the water main at the site. It remains the case that the key issue for progress is Welsh Water’s requirements and hopefully this will be known next week
“Any estimated timescale for re-opening the road is dependant upon this and further updates will be provided as soon as possible.”