the transportation manager paul liston is back in the passenger compartment instead of being by his side required by b.a.r.t.'s rules. the trainee has summoned his help repeatedly. >> hey, paul, i don't know what i am trying to do wrong, but i am trying to set the new destination code, but it is not wanting to take it. >> okay. in a minute. >> and liston is talking about his training needing some more attention. >> reporter: are but the records that we obtained show ed thed t was texting and talk on the telephonea and he is chatting with the colleagues about the upcoming world series. >> reporter: just after 1:00 p.m., b.a.r.t. issued a radio alert about a crew on the tracks. b.a.r.t. engineer christopher shepherd and lawrence daniels were here checking on a dip in the rail north of walnut creek station. they had ventured upon the tracks that allowed them to gauge the risk alone, but they did not realize they were behind a ongoing curve that kept them from being seen by a train until it is too late, and not the required lookout. at 1:30, b.a.r.t. was supposed to issue another radio alert

transportation manager paul liston is back in the passenger department instead of as being by his sidenee has to summon for him to help repeatedly. >> hey, paul, i don't know what i'm doing wrong. but i'm trying to set the new destination code but it doesn't take it. i don't know if i'm doing it wrong. >> hold on one second. >> at one point he kids about his trainee needing so much more attention. >> how many more times are you going to make me get up [ bleep ]. >> reporter: but records showed that he was texting and talking on his cell phone, both violations of b.a.r.t. policy. he chats with colleagues about the upcoming world series. >> did the dodgers get beat last night? >> yeah, nine to zero. >> oh, my goodness. oh, my goodness. so it's st. louis and then they're waiting, right? >> reporter: just after 1:00 p.m. b.a. rmp t. issued a radio alert about a crew on the tracks. b.a.r.t. engineer christopher shepard and consultant lawrence daniels were here checking on a dip in the rail. they had ventured onto the tracks under bart's rule to gauge the risk but they didn't realize they we

transportation manager paul liston is back in passenger department.r being at his side as required by b.a.r.t.'s rules. the trainee has to summon for him to help repeatedly. >> at one point liston kids about his trainingee needing so much attention. but records we reviewed showed that liston was actually texting and talking on his cell phone. both violations of b.a.r.t. policy. the video shows he chats with colleagues about the upcoming world series. just after 1:00. b.a.r.t. issued a radio alert about a crew on the tracks. sheppard and daniel were here check on a dip in the rail north of walnut creek station. they ventured oont the tracks that b.a.r.t. rules allowed them to gauge the risk. they didn't realize they were on an curve that. they didn't have the required look out. at 1:30 p.m. b.a.r.t. was supposed to issue another radio alert. the alert never came. it's 1:44 p.m. as the operator heads into the deadly blind curve. he briefly spots the crew in the distance. not sure what they're doing. he continues into the curve at full speed. 68-mile-per

although bart now says he broke several of its rules, assistant chief transportation officer paul listonout any discipline. neither he nor the trainee got back to us for comment. jaxson vanderbeckin, "nbc bay area news." >> thank you. recently the effort to fine bart suffered a blow when the regulatory sided with bart's lawyers. if you have a tip for our investigative unit give us a call. 888-996-tips or send an e-mail to the unit at nbcbayarea.com. >>> let's get back to breaking news we have been following this morning where we are learning more about the bomb that the u.s. military says it dropped on an isis target in afghanistan today. the nickname of the munition is the mother of all bombs. it is the largest non-nuclear bomb the military has in its arsenal. that's a p ma of where it happened in eastern afghanistan on the border with pakistan. the pentagon says it is a gbu-43 bomb officially. it contains 11 tons of explosives. >> and today was the first-ever combat use of that bomb. it was dropped on a cave complex believed to be used by isis fighters. this in the achin strict close t