Combat Camera: US Marines Investigate Insurgents' Underground Highway, Nimruz Province, Afghanistan

The 2nd Battalion, 3rd Marine Regiment's Cpl. Tavares Taylor lowers a reconnaissance robot into an 80-foot karez Sept. 23, 2009. The Marines were investigating tunnels in the district's karez system - a network of wells and tunnels hundreds of years old - that are suspected to have been used by insurgents as caches for IED making materials. (Photo by Gunnery Sgt. Chris W. Cox, Regimental Combat Team 3.)

The 2nd Battalion, 3rd Marine Regiment's Cpl. Jason L. Paul radios his patrol's security element as battalion commander Lt. Col. Patrick Cashman observes a reconnaissance robot's camera feed on Markbot operator Cpl. Garrett Andrews' laptop Sept. 23, 2009. The Marines based at Forward Operating Delaram near here were investigating tunnels in the district's karez system - a series of wells hundreds of years old - that are suspected to have been used by insurgents as caches for IED making materials. (Photo by Gunnery Sgt. Chris W. Cox, Regimental Combat Team 3.)

The 2nd Battalion, 3rd Marine Regiment commanding officer Lt. Col. Patrick Cashman and radio operator Cpl. Tavares Taylor approach an 80-foot karez to investigate it as a possible insurgent cache Sept. 23, 2009. The Marines were investigating tunnels in the district's karez system - a network of wells and tunnels hundreds of years old - that are suspected to be used by insurgents to store IED making materials. (Photo by Gunnery Sgt. Chris W. Cox, Regimental Combat Team 3.)

The 2nd Battalion, 3rd Marine Regiment's Cpl. Tavares Taylor lowers a reconnaissance robot into an 80-foot karez as Markbot operator Cpl. Garrett Andrews guides it with the remote controller Sept. 23, 2009. The Marines were investigating tunnels in the district's karez system - a network of wells and tunnels hundreds of years old - that are suspected to have been used by insurgents as caches for IED making materials. (Photo by Gunnery Sgt. Chris W. Cox, Regimental Combat Team 3.)

Dispatches from the Front:

FORWARD OPERATING BASE DELARAM, Nimruz province, Afghanistan, Oct. 4, 2009 --Some people go cave exploring for fun, but when there is a possibility of stumbling on explosive materials, an armed enemy or a nasty surprise they've left to be triggered in the dark, it's about as far from fun as you can get.

Marines from 2nd Battalion, 3rd Marine Regiment are searching wet, pitch-dark tunnels ranging from 40 to 100 feet underground that connect the karez system – a network of wells and tunnels between the snow-capped peaks of the Buji Bhast mountains and the arid desert plain here. The karez system was originally constructed hundreds, maybe thousands, of years ago. These days, insurgents are using these tunnels as a form of covert transportation and storage for IED-making materials. The Marines are putting a stop to that.

"We've found evidence of weapons, dwelling, trash. We know they're down there," said Company E executive officer, 1st Lt. Husein Yaghnam.

"We can't collapse them because that will affect the farmers' irrigation system, but we can deter the enemy from using them," said the Toledo, Ohio, Marine. "It might open up opportunities just by deterring the enemy from using them."

What's it like descending along the sheer walls of these holes that travel all the way down to the limestone bedrock?

"It's kind of scary, because you don't know what's in the wells," said Personal Security Detachment platoon sergeant Cpl. Jason L. Paul from Shiprock, N.M. The PSD Marines provide security for the battalion commanding officer, Lt. Col. Patrick Cashman, who sometimes personally investigates the wells for his own situational awareness.

"They're usually 40 to 60 feet down – straight down – and it's really dark down there," he described. "Every time we head down, I always tell my guys to be careful."

Fortunately for these young men weighed down with gear, drinking water, weapons, ammunition and a flashlight, going down on foot isn't always the first option they try. Sometimes they send down a robot – with varying degrees of success.

"Yesterday we sent the bot into three holes. In the first one it could only go in about eight feet, so we had to go in, retrieve it and investigate on foot," said Markbot operator Cpl. Garrett Andrews the day after a series of tunnel hunts. "Later we sent the bot down but didn't see any man-made passages."

In addition to deterring the enemy from using the karez, the Marines are also trying to determine which wells will be irrigating which fields before planting season arrives in a few months.

"We're also looking at the locals growing poppy," said Paul. "Yesterday, we found one that is actually being used to water their fields."

By identifying which wells are directly connected to potential poppy farmers, the Afghan government may be able to convince them beforehand to grow a different crop as they are doing in neighboring Helmand province. Two different areas there – Garmsir and Nawa Districts – have seen a measurably decrease in poppy growth since government workers began distributing bags of wheat seeds around last year's planting season. This year's program is already in full swing.

Before that can begin here though the Marines still have a lot of work to do, and their recent activity around the ancient well system has drawn notice.

"Yesterday, the locals were driving by really close taking peaks here and there," said Paul. "The local insurgents see that too. They're looking at that to see if that's another way to get us. We're planning for that."

(Report by Gunnery Sgt. Chris W. Cox, Regimental Combat Team 3.)

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