California drivers are bracing for a substantial increase in gas prices starting July 1, as multiple new taxes and regulations take effect. Experts are divided on just how high prices will climb, but some estimates suggest they could reach up to $6 per gallon.

The first factor contributing to the price hike is an increase in the state’s excise tax, which will rise by 1.6 cents per gallon. However, this is just the beginning of the cost increases.

A more significant impact is expected from the Low Carbon Fuel Standard program, approved by the state’s air resources board in November. This program aims to reduce California’s greenhouse gas emissions, but will result in stricter regulations on gas producers.