20 Years of Experience
While I'm on the topic of the H Mart entrance, let me address that problem first. It is a constant hazard because drivers entering and exiting that driveway ignore basic right-of-way laws. This is not an issue that can wait for long-term changes to be implemented, either. Someone needs to be standing out there at rush hour issuing citations. It's the only way to stop these drivers from breaking the law and would have more impact than photo enforcement. Even one day of enforcement and one driver pulled over with flashing lights would send the message.
The problem is this: Drivers heading south on Jermantown or turning right into the intersection on Route 50 get backed up waiting for the light to change. They are generally careful not to block the driveway of H Mart parking lot, and when traffic is stopped, it's accepted that customers can turn left across traffic to enter the driveway or to exit into the southbound lanes. What is not acceptable is when traffic is flowing into the intersection on a green light or turning right on a red light, for customers to turn into and out of the driveway cutting off oncoming traffic. They act as if they have right of way! It's especially dangerous when the middle southbound lane is backed up waiting for a green, but the right hand turn lane is empty and a driver is heading south in this lane. A customer turning left into the parking lot across the lanes of traffic cannot see the oncoming car because their view is blocked by the middle lane of stopped traffic.
The other extremely hazardous scenario is when the light turns green, and the three southbound lanes of traffic on Jermantown Road begin to move. There's a lag in how quickly all these stopped cars can get going. They're impatient to catch the light, because they've been stuck in line, sometimes for more than one light. As these cars start moving, it's normal that there are are gaps between them as the cars behind hustle to catch up. It is exactly at this moment, dozens of times daily, that H Mart drivers will dart into these gaps to enter or exit the driveway. It is hair raising and maddening to be driving at speed southbound on Jermantown, trying to catch the green light you are entitled to, only to have customers blindly cutting you off with no regard for safety or right of way. At its most innocent, it disrupts the flow of traffic and further contributes to the congestion at the intersection.
Solutions: Immediate: Ticket these drivers! Intermediate: Add signage to this driveway to include a stop sign for right turn customers and cautions to respect right of way. Long term: Possibly close off this driveway so that customers are forced to use the parking lot driveway several yards north that actually has a stop light for ingress and egress, or the driveway that exits onto Route 50 on the southern side of the parking lot. The driveway on Jermantown with traffic light is designed to allow large container trucks to back up to unload their shipments. It's a very tight fit. Short of H Mart redesigning their loading bay and moving it to another area of the parking lot, I don't see how you could close off that driveway. While entering the driveway from the left turn lane on Jermantown is more problematic, the fact is, I've used these two other driveways as a customer for 20 years and they are completely satisfactory as exits. Yes, you have to wait your turn, but that is what H Mart drivers need to learn to do.