captioning sponsored by newshour productions, llc >> sreenivasan: good evening. i'm hari sreenivasan. on the newshour tonight, republicans hold a civil debate before next week's crucial primaries, while ben carson becomes the second former rival to endorse frontrunner donald trump. >> woodruff: i'm judy woodruff, here at the site of nancy reagan's funeral in california, where a nation said farewell to an influential first lady. >> she had an instinct for reading people that president reagan knew he lacked. nancy, he wrote, sees the goodness in people, but she also has an extra instinct that allows her to see the flaws. >> sreenivasan: it's friday. mark shields and david brooks are here, to analyze the week's news. also ahead, miles o'brien's rare look inside fukushima-- five years after the meltdown, the historic cleanup continues.

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>> this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> sreenivasan: republican candidates-- past and present-- were out on the stump today. all eyes are on key states, like florida and ohio, set to vote in the primary on tuesday. >> i just want to introduce dr. ben carson, a special, special person, a special man. thank you very much. >> sreenivasan: republican frontrunner donald trump proudly presented his latest big name endorsement in palm beach this morning: former rival ben carson. >> there are two different donald trumps. there's the one you see on the stage, and there's the one who is very cerebral, sits there and considers things very carefully.

you can have a very good conversation with him. that's the donald trump that you're going to start seeing more and more of. >> sreenivasan: trump embraced the endorsement and said it was a sign republicans are getting behind his campaign. >> i've been hearing from virtually everybody in the republican party and they are congratulating me. they are saying we're going to come together. >> sreenivasan: he was coming off yet another republican debate, where the tone shifted to near civility, dialing back on the bravado. >> and so far i cannot believe how civil it's been up here. >> sreenivasan: but his rivals weren't willing to concede anything. ohio governor john kasich leads in the polls in the buckeye state, one of five holding their primaries next tuesday. >> well, first of all, let's not-- you know, math doesn't tell the whole story in politics. you have to earn the delegates in order to be picked. but let's not get ahead of ourselves. we don't know what's going to happen because we still have about half the delegates to be selected. and that's what's going to be a very interesting thing to see

how it all turns out as we move forward over the next couple of weeks. >> sreenivasan: texas senator ted cruz argued only he has the chance to beat trump: >> there are only two of us that have a path to winning the nomination, donald and myself. at this point, i have roughly 360 delegates. he has about 100 more than i have. we have at this point beaten donald in eight separate states all over the country >> i watch ted on television and when he speaks, and he's always saying, "i'm the only one that beat donald in six contests; and i beat him." but i beat him in 13 contests. he never mentions that. >> sreenivasan: trump also responded to violence against protesters at his rallies, including one assault caught on videotape wednesday. >> some of your critics point to quotes you've made at these debates-- at these rallies, including february 23, "i'd like to punch him in the face," referring to a protester; february 27, "in the good ol' days, they'd have ripped him out of that seat so fast;" february 1, "knock the crap out of him, would, you?

seriously, ok, just knock the hell. i promise you i will pay for the legal fees, i promise, i promise. >> sreenivasan: trump did not condone the violence but said: >> we had a couple big, strong, powerful guys doing damage to people-- not only the loudness, the loudness i don't mind-- but doing serious damage. and if they've got to be taken out, to be honest, i mean, we have to run something. >> sreenivasan: and today at trump's rally in st. louis, protesters employed a new tactic, staggering their interruptions one at a time throughout trump's remarks. >> sreenivasan: florida senator marco rubio urged voters to consider the impact of their choices on tuesday-- and how to vote in both his home state and in ohio. >> if a voter in ohio is motivated by stopping donald trump and comes to the conclusion that john kasich is the only one who can beat him there, i expect that is the decision they'll make. i can tell you that in florida i'm the only one that can stop donald trump, and whether

someone supports ted cruz or john kasich, if you vote for them in florida, you're in essence voting for donald trump, and if a voter reaches the same conclusion in ohio than that's what they're going to do as well. >> sreenivasan: without wins in their home states, rubio and kasich face the end of the road for their runs. meanwhile on the democratic side, vermont senator bernie sanders courted voters in north carolina, ohio and illinois. but former secretary of state hillary clinton put aside campaigning today to attend the funeral of fellow first lady nancy reagan in california. we'll get mark shields and david brooks' take on the state of the presidential race later in the program. in the day's other news, there was little relief for residents in flood-stricken louisiana, as overnight downpours brought total rainfall to two feet in some places. in monroe, louisiana-- one of the hardest hit communities-- floodwaters caused major damage, uprooting trees and collapsing roads. meanwhile, the national weather service warned more rain is on the way this weekend. some places along the alabama coast could see six additional inches.

the u.n. warned today, south sudan has become "one of the most horrendous human rights situations in the world." the new report detailed atrocities by government forces- - including cases of children and disabled people burned alive and parents forced to watch as their children were raped. the country has been mired in civil war since 2013, leaving tens of thousands dead and millions more displaced. i spoke with david marshall, coordinator of a u.n. human rights mission to south sudan, via skype earlier today. >> our findings were quite stark-- that war crimes and crimes against humanity have been perpetrated in 2015 by the government. the government has instilled or undertaken a campaign of terror in the country to displace, kill, rape, loot and destroy civilian property. >> sreenivasan: to see our full interview with david marshall on the atrocities in south sudan, visit our website, www.pbs.org/newshour. the number of north korean cyber attacks on the south have

doubled over the past month. south korean intelligence officials sounded that warning today to parliamentary lawmakers. they said the north tried, but failed, to hack into their railway control system and computer networks of financial institutions. the hackers also stole information from the smartphones of dozens of south korean officials. president obama nominated u.s. army general curtis scaparrotti to be nato's new top military commander. scaparrotti, currently commander of u.s. forces in south korea, will succeed u.s. air force general philip breedlove as nato's supreme allied commander of europe. the nomination-- pending senate approval-- comes amid ongoing tensions with russia and a refugee crisis plaguing europe. a south african man says his son may have found a piece of missing malaysian airlines flight 370, in mozambique. the teenager found the part on december 30 in the town of xai xai, thousands of miles from the flight's last known coordinates. the piece has a five digit

number on it, which authorities said indicates it may belong to a boeing 777. officials are sending it to australia to be examined. in japan today, mourners marked the fifth anniversary of the 2011 earthquake and tsunami that killed more than 18,000 people. the country's northeast coastline was devastated, and still hasn't been fully rebuilt. japanese officials, including prime minister shinzo abe, held a moment of silence in tokyo. he struck a positive tone in a speech at the altar for victims. >> ( translated ): in the past, our nation suffered countless disasters that could be described as national crises, but overcame them each time with determination and hope. i vow once again that we will follow hand in hand in the footsteps of our forefathers and continue to move forward. >> sreenivasan: the anniversary also sparked protests against nuclear power, after the meltdown at the fukushima daichi power plant. we'll have more on the cleanup efforts there later in the program tonight. the department of health and human services pledged $94

million to help fight against heroin and opioid drug abuse. the money will go to 271 centers across the country and be used to treat roughly 124,000 new patients. it comes a day after the senate overwhelmingly passed a bill to help state and local programs, but that measure did not include any new funds. the world anti-doping agency announced there have been 99 positive tests for meldonium this year. that includes russian tennis star maria sharapova's sample. the blood-flow boosting drug was banned on january first for its performance-enhancing benefits. sharapova admitted she's been taking it for a decade for health issues but didn't know it had been banned. at least seven of the confirmed cases come from russian athletes. they face up to a four-year ban. stocks closed higher on wall street today to round out a four-week rally. the dow jones industrial average gained 218 points to close at 17,213. the nasdaq rose 86 points,

and the s&p 500 gained 32. for the week, the dow and s&p gained more than a percent. the nasdaq rose just under a percent. astronaut scott kelly announced his retirement. worked for n.a.s.a. nearly 20 years and holds the record for the most cumulative time in space at 520 days. still to come on the newshour, first lady nancy reagan laid to rest; mark shields and david brooks analyze the week in news; the cleanup continues five years after the fukushima nuclear plant disaster, and much more. >> sreenivasan: there were recollections and prayers today for first lady nancy reagan at her funeral service held in the hill country northwest of los angeles. family, friends and first ladies past and present were in

attendance, as well as president george w. bush. here are some excerpts from today's service at the reagan presidential library. ♪ >> we gather here today to say goodbye to nancy davis reagan. a beautiful, smart and gracious woman. a woman who captured the heart of a man who loved his craft, his country, and his countrymen. and most especially loved this remarkable woman. a woman without whom ronald wilson reagan would never have become the 40th president of the united states or succeeded as well as he did. she had an instinct for reading people that the president knew he lacked. nancy, he wrote, sees the

goodness in people, but she also has an extra instinct that allows her to see the flaws. the only time i saw her lose her composure was the day the president was shot. she was devastated and in fact she fell apart. president reagan left the hospital convinced that god had spared him for a special purpose. and the first lady left with a fierce determination to protect him in every way that she possibly could. ronald and nancy reagan were defined by their love for each other. they were as close to being one person as it is possible for any two people to be. >> my parents were two halves of a circle. closed tight around a world in which their love for each other was the only sustenance they needed. while they might venture out and include others in their orbit, no one truly crossed the

boundary into the space they held as theirs. it's no secret that my mother and i had a challenging and often contentious relationship. our emotions burned up the color chart. nothing was ever gray but there were moments in our history when all that was going on between us was love. i choose to remember those moments. >> today my mother comes to rest on this lovely hilltop with its far-reaching views next to her beloved ronald reagan library. and from here she will be able to keep an eye on things. but most importantly she will once again lay down beside the man who was the love of her life. the one she loved until the end of her days. they will watch the sun drop over the hills in the west toward the sea. as night falls they will look

out across the valley; my father will tell her the lights below are her jewels. the moon and stars will endlessly turn overhead. and here they'll stay, as they always wished it to be, resting in each other's arms. only in each other's arms until the end of time. >> sreenivasan: judy woodruff attended the service today, and she joins me now from simi valley. judy, your thoughts on what happened. >> woodruff: well, hari, it's raining now, but the sun was shining brightly as the funeral service unfolded here at the ronald reagan library in simi valley. it was the most beautifully choreographed funeral, if you want to put it that way, that one could imagine. the flowers on the casket were spectacular. the crowd was full of celebrities and people who served in the reagan administration, a number of influential republicans.

the service was poignant and it was funny. there were a lot of funny stories about nancy and ronald reagan and how close they were. all in all, it was classic nancy reagan. >> sreenivasan: and, judy, nancy had a lot to do in the planning and orchestrating who would do what in this ceremony, right? >> woodruff: exactly. the people who know her said, again, this is just exactly like what you would expect from the former first lady. she was close to her husband and wanted to make sure everything was perfect for her husband and carried that on through the rest of her life until his death a little over ten years ago, and she felt the same way about her legacy because she saw it connected to his, so she wanted today's ceremony, the service to reflect the two of them, and that's really what it was. it was planned to the t the program, who the speakers were, the music, the minister, everything, in a spectacular

setting here in the santa lucia mountains in california. >> sreenivasan: was the a reunion of reagan administration staff or were there people from across the aisle as well? >> there were both. the reagan administration represented by secretary of state james baker, people like ed meese, part of the reagan white house, so many of the press corps who covered the reagan white house as i did, it was a collection of the reagan family in addition to the staff and the press. but there were democrats here as well. we saw -- in fact, i saw vicky kennedy, the widow of senator ted kennedy here, and a number of others. so it wasn't, i would say, a partisan event, but it was very -- it was heavy on republicans, which was exactly what you would expect from the widow of this president who represented the republican -- a

republican icon. >> sreenivasan: i want to bring syndicated columnist shields shield and "new york times" columnist david brooks here as well. your thoughts. >> just to add to fill out the point about being bipartisan, governor jerry brown was there whose dad ronald reagan defeated to become governor in 1966, the current governor, then democrat of california along with rosalind carter, the first lady, as well as, of course, hillary clinton, the former first lady and frontrunner for the democratic nomination. but nancy reagan, the irony to me is that ronald reagan is the first of the 44 presidents and only divorced man ever elected, and yet they are remembered as a couple, an incredibly devoted couple for better, for worse, in sickness and health couple. he was a formidable presence. i met her. i did not know her. judy knew her well, but she was

a formidable force in personnel choice in the administration, in the white house, and she was responsible for what would have been ronald reagan's most correspondent hire, that of jim baker, chief of staff, who had run the last two campaigns against ronald reagan, that of george h.w. bush in 1980 for the nomination and gerald ford in 1976, even, with her. but she reached across and recognized talent and thought it was in the best interest of "her ron "as she called him. >> i remember the tom cruise line, you complete me, and they did. it was a tremendously fulfilling love for both of them. they completed each other's emotional needs. so some people were shut out, patti davis and some of the reagan staff thought they were shut out from that and along with that ferocity was a

protectiveness. the first ladies are more aggressive on behalf of the presidents than the husbands themselves. they're always tougher in the white house and they're willing to get rid of people and she certainly was willing to get rid of people who she thought wasn't serving her husband as well. the dinners were always extremely glamorous in those years for the republicans and she was sort of the architect of those. >> she liked being first lady. she liked washington. it came through. we in washington, the permanent washington, whoever we are, we tire of people who spend time, effort, energy and millions of dollars to get here to tell us how much they hate it and how unhappy they are here. she really was happy as first lady. >> sreenivasan: judy, was there a moment that stood out for you? >> woodruff: well, there were several. i'm listening to david and mark speak about the relationship between the ragens.

as jim baker said it here, they were as close as two people could be and not be one person, and the point about their circle of closeness was to impenetrable, in the words of their son ron reagan, that no one else could get through, including their children, and that came through in a very poignant way in what both children said in how they felt, they loved their parents but they knew who came first, and that was their parents, it was the president and the first lady. >> sreenivasan: all right, judy. thanks so much. see you back here on monday. >> woodruff: see you then. >> sreenivasan: let's continue the conversation about the week in politics. last night's g.o.p. debate could have possibly been on pbs. it was definitely a different tone and vibe. why do you think that was? (laughter) >> yeah, i think it was because the other candidates decided, especially marco rubio, that if they go after trump the way they

were in the gutter that they end up hurting hemselves, and i think there is evidence from rubio to that effect. it was a more rubio style debate and thought he did well because it was stan tift, uplifting and he did well but not substantially enough to change the nature of the race, i don't think. >> not for the first time, the campaigns are like parallel skiing, you're competing in ohio while your opponents are in tampa, florida or dearborn, michigan and a debate brings you all together. this is a chance for you to rearrange the standing, especially if you're blind and last night there was none of that. rather than pbs, i would say it was c-span subcommittee hearings on subcommittee of weights and measures, about that, stimulating, instead of the past debates which had been like the housewives to have the jersey shore and you turn it on expecting someone to throw a household appliance at the other. i think david's right.

i think they found out it didn't work. it worked for donald trump but it doesn't work to be a mini trump, as marco rubio proved, but also, i think, hari, that may be the opening admission, acknowledgment that donald trump is going to be the nominee because if you pass up a chance to really take a shot and to try and change the chemistry and the dynamic of the race and you don't get that many opportunity where everybody is watching at the same time, i think the failure of people to engage trump last night almost an admission, may be the beginning to have the concession. >> sreenivasan: let's talk about what's at stake coming up tuesday with ohio and florida, two big otherwise general battleground states. yesterday comments were made on stage by donald trump saying, look, two of us have the possibility here, two of us don't. is that basically the case in terms of governor kasich and marco rubio, if they don't win their home states do, they pack up? >> rubio probably does. you know, if they win their home states, then donald trump has to get nearly 60% of the remaining

delegates or nearly 70% of the remaining delegates, and that's a tall order. if kasich and rubio win, we look going into the convention without at least a clear nominee. if they lose, i think rubio probably has to get out. you get the sense, the vibe the air is popping out of his campaign, a really bad event in the football stadium, and just a lot of republicans sort of walking away. kasich, on the other hand, maybe because he started lower, he's still got some energy around his campaign and, so, i think he can lose and hang in there. if it was he, cruz and trump, kasich, a lot of people might go to him. the trump wins both he'll probably win them all tuesday. it's just the biggest day of the season and you have to think he's probably the nominee. >> john kasich is interesting. he's run a positive campaign, the governor of ohio and has not

gotten into the back and forth and the insult exchange that has dominated most of the republican debates. for first time, donald trump is running an anti-kasich commercial in ohio, and it will be interesting to see what john kasich does in the next few days, is he a pacifist or does he hit back? it's obviously an invitation. trump wants to win ohio. he has urban meyer, the football coach at ohio state, perhaps the most popular figure in the state, if it isn't an endorsement, it's certainly an embrace that he's cut with kasich and john kasich's family, speaking glowingly of things kasich's mother had not been aware of before.

>> sreenivasan: when he goes into that convention, what does he do there? is this a matter of saying, hey, it's open and i think i'm still a viable candidate and, by that time, people will see me as the guy that they want to nominate? >> well, let's play it out. if trump does not have the majority of the delegates, and they can sort of rewrite the rules, i think there will be a period preconvention where the candidates will go in after the del cats -- delegates, the republican, and say commit to me and they will try, the candidates, to win the delegates over and it becomes a bidding war. then it will all be quiet and they'll try to commit before we geto the convention and i suspect most of the delegates will lie and say, yes, mr. trump, i'm with you, and mr. cruz, i'm with you, too. then we don't know what happens, then it's complete chaos. >> i don't know how john kasich goes after ohio. i don't know where he mounts a campaign that makes him a competitor, a serious challenger

for the nomination. he can certainly go to the convention in cleveland and having carried ohio, if he does so, that's not unimpressive by any means. but if trump is within 100 delegates of the nomination, he'll get them. i've seen candidates get 100 people who know the chance of being the next president of the united states and certainly the nominee and they want to be on the good side of the nominee. >> maybe with 100. but trump is a unique candidate. there is more opposition to trump. i've felt it all week, so many people. you go to them, some members of congress and activists and say could you support trump and they say, i just couldn't pull the lever. he's unique in that regard. >> sreenivasan: why is this race on the democratic side still continuing? conventional wisdom was that hillary clinton would have a formidable lead, she would be the clear and distant choice,

but in cases like michigan, not so. >> no. when sanders personnel pointed out to me, when you take out the red states of alabama, mississippi, south carolina, louisiana, georgia, arkansas, and bernie is doing pretty darn well, i mean, that's where secretary clinton has run up the score and done so well with large african-american votes in those states. but bernie sanders was -- being 21 points behind in the polling, primary polling brought a new respectability to astrology. it was so wrong in michigan. i just think you have to come back. it's not the messenger. he's not a charismatic guy that bobby socksers are are swooningn front of. it's the message. you can see it. first time you see the republican voters in the exit polls in addition to democrats saying they oppose free trade,

they see free trade as outsourcing of jobs and offchauferring. so -- see it as off-shoring and not in economic and family's interest, so it's a burning message. >> the whole debate shifted on that side. i think it's also her weakness as a candidate. she sometimes has a good message, but on a tack, we're reminded she's not good. she attacks wildly without focus and i think unpersuasively. the one thing i really like she did this week is confess the vulnerability, i'm not my husband or barack obama, not as politically gifted as those guys. i think that's true but also an honest way to approach the american people. >> good point. >> sreenivasan: david brooks, mark shields, thanks so much.

>> sreenivasan: and you can get mark and david delivered to your inbox every friday. sign up for newshour's politics emails by clicking the "subscribe" icon on our homepage. that's at www.pbs.org/newshour. >> sreenivasan: now, how do you rebuild from a cascade of disasters? five years ago today, japan was rocked by a massive earthquake and a catastrophic tsunami. the fukushima daiichi nuclear plant was crippled by the tremors and waves, triggering a meltdown that forced roughly 100 thousand people from their homes, spewing radioactive material into the ocean and nearby countryside. science correspondent miles o'brien has a rare look inside fukushima to see how the massive clean-up project is pressing forward. his report is a partnership with pbs program nova. >> reporter: fukushima daiichi was one of the largest nuclear power plants in the world. today, it is a busy, crowded, dangerous de-construction site.

my invitation to see it up close was unique. what next? does three have a lot to--? but even with special permission, getting inside is not easy-- by design. radioactive contamination levels have gone down, but not nearly enough to dispense with the tyvek suits, three layers of socks and gloves and full face respirators. it's like being an astronaut on a spacewalk. here, 7,000 workers are doing a job for which there is no playbook. >> ( translated ): what makes this so difficult is the lack of experience. nobody in the world has done this before. >> reporter: naohiro masuda is the chief decommissioning officer for the tokyo electric power company-- tepco. >> we still need to decide what

we're even going to do. for that we need to rely on the knowledge of people all around the world. >> reporter: he relies heavily on this man. >> for them to come out and to publicly say, "we need help," is different for them. >> reporter: lake barrett is one of a very select group who has some experience with a job like this. he was the nuclear regulatory commission manager in charge of the decommissioning of three mile island unit two-- near harrisburg, pennsylvania. it melted down in 1979. >> fukushima is much more complex. the damage is much greater. there are three melted cores, but the fundamentals of how you address this and how you recover are similar. >> reporter: the daily details of this 40-year job are managed here in a radiation shielded, earthquake proof emergency operations center. the superintendent is another tepco veteran, akira ono-- on duty here since june of 2013.

>> ( translated ): ever since the disaster, we've been working here 24 hours a day, 365 days a year. we're ready to respond to anything that happens. >> reporter: his biggest problem is water-- a steady torrent of radioactive water. when the rain falls, it seeps into the soil, and flows toward the ocean. the earthquake on march 11, 2011 created numerous breaches in the basements of the reactor buildings. the groundwater is contaminated after it mixes with water that is continuously pumped onto the damaged reactor cores. 100,000 gallons of newly contaminated water is created here each and every day. they capture and pump most of it into holding tanks-- lots of tanks. they build one about every other day. a plateau above the destroyed

reactors is now a tank farm, brimming with more than 1,000 of them. but have they managed to stop all the radioactive water from leaking into the ocean? what we're hoping to find is a container full of water-- in this lab at the woods hole oceanographic institution, they have been tracking radioactive water from fukushima since the accident. >> the level is still measurable and quite elevated, but it's not anywhere near what it was at the peak of the accident. >> reporter: oceanographer ken buesseler says readings in april of 2011, showed cesium levels 50 million times higher than normal at the plant. >> the numbers dropped very quickly, but they also didn't go down to zero. they didn't go to the background as quick as you would expect if they had stopped the leaks. >> reporter: they hope to stop the toxic leaks by building a barrier. they have encircled the damaged reactors with 1,500 pipes that go 100 feet deep.

they will be filled with coolant. the goal: deep freeze the soil, creating a mile-long water barrier. the technique has long been used in construction-- to build tunnels. but can it work at this scale for years and years? dale klein is a former u.s. nuclear regulatory commission chairman and now an advisor to tepco. >> if you have water flowing to the site and you build a barricade, water's going to go somewhere. do they really understand? is it going to go over the wall, is it going to go under the wall, is it going to go around the wall? so my concern is there is probably a better way to do it. >> reporter: the long-term solution is to find and remove the uranium fuel from the four reactors affected. they have started the process by removing fuel that was in underwater storage. at unit four, which was powered down when the tsunami hit, they built a structure over the damaged reactor, using it as a platform to carefully pluck out

more than 1,500 fuel assemblies. but in units one, two and three, where the reactor cores all melted down, radiation levels are much higher-- making the task much more daunting. >> people are probably not going to have access to those buildings for more than maybe a minute or two, so not enough to do defueling. >> reporter: and what about the melted fuel in the reactor cores? they aren't even sure where it all is. >> is it in one big vertical lump on the floor underneath it, or did it come down and flow like lava in a volcano and move out to the sides? we don't know yet. >> reporter: tepco has turned to a team of scientists and engineers from the los alamos national laboratory for some assistance. they are helping build a device designed to see through the walls of the reactor buildings and hopefully make what looks like a three dimensional x-ray of the reactor cores.

these long cylinders are able to detect muons-- subatomic particles created in space by quasars and supernovas that rain down on the earth. muons are stopped, slowed or deflected depending on the density of the matter they are passing through. and uranium is very dense. physicist chris morris leads the team. >> you can reconstruct the amount of material at the core in the reactor. we can actually measure if there's any uranium there, if there's a lot of uranium there, how much is left. >> reporter: the detectors will be run for months to give engineers the sharpest possible picture inside a very hazardous place. >> human beings aren't going in there anytime soon. the radiation levels are very high. it kills robots. >> reporter: the robots they have tried here so far have offered up glimpses inside the

melted nuclear cores, before failing in the face of a bombardment of radiation. japanese robotics engineers have their work cut out for them. >> i believe is can be done. it can be done safely and it can be done successfully. but nothing of this magnitude has ever been done by mankind. >> i feel very reassured that in the next 30 or 40 years, people from all over the world will gather in fukushima, to work and research the decommissioning. i'm hoping it will become a very lively place. >> reporter: fukushima-- five years later. they have made progress here, but it is just the beginning of a marathon. this cleanup will rely on technology not yet invented, and the determination of people not yet born. i'm miles o'brien, for the pbs newshour in futaba, japan. >> sreenivasan: stay tuned--

this fall, miles will have a new documentary on fukushima for nova. and right now, you can read his blog on the real heroes behind the nuclear disaster. that's on our website, www.pbs.org/newshour. >> sreenivasan: we'll be back with a look at how syrians artists are depicting their experiences of the ongoing civil war. but first, take this moment to hear from your local pbs station. it's a chance to offer your support, which helps keep programs like ours on the air. >> sreenivasan: for those stations still with us-- it's been more than 150 years since the start of the california gold rush. though dreams of striking it rich may have faded for many, there are still some in the u.s.

hoping to strike it rich in streams and creeks. one method of mining for gold is at the center of a growing debate between miners and environmentalists. in washington state, the controversy has reached a fever pitch. tonight, we take another looks at a report from correspondent nils cowan from member station kcts in seattle, and earthfix-- a public media partnership. >> reporter: in the rugged mountain wilderness of washington state, a unique group of enthusiasts is carrying on an age-old tradition. >> we're probably going to put the dredge right here. >> right in that area, okay. >> reporter: they're searching for gold. >> gold has always had an allure for man, and man has always chased it. >> reporter: for modern small- scale miners like ron larson, the most effective tool is a fairly new invention known as the hydraulic dredge. >> locked and loaded. >> a hydraulic dredge is essentially a floating platform with a power plant that supplies air and power to move water over

a riffle box to sort out the heavy material. gold is heavier than every other mineral in the stream, and the only way to get the gold is to remove what is called overburden. >> reporter: to strip away this layer of rock and sediment, miners are equipped with diving gear and a high-powered underwater vacuum. also known as suction dredging, this method allows miners to go through as much as 40 times more sediment than non-motorized mining. but growing concern over possible environmental impacts has caused lawmakers in california, oregon and idaho to take action to restrict it. that leaves washington as one of just a few western states to allow dredging in most of its waterways, setting up a key battle between small-scale gold miners-- >> there's a dredge right over here. >> oh yes. >> reporter: --and the activists looking to shut them down.

in central washington, a team of fish enthusiasts and environmental activists is heading into prime dredging territory. they're looking for evidence of how this mining method impacts fish. >> wow. are you kidding? >> they have altered the channel of the water, so that they can bring it into their sluice. >> reporter: gregg bafundo is the washington field coordinator for trout unlimited. >> we're here, and we're fisherman, and we're concerned. we have been seeing waters getting warmer. we have been seeing droughts across the west that have been impacting fish. and right now, we have steelhead that are trying to get upstream to spawn, and they can't. >> reporter: farther upstream, bafundo and restoration ecologist crystal elliot-perez check for impacts to water quality just below a dredging operation. >> when you run sediment through a sluice, and then you get a sediment plume coming out the back end, that impacts turbidity or increases turbidity. >> reporter: excess sediment

makes it difficult for fish to breathe and can cause water temperatures to rise to harmful levels. >> remember what it was back there? >> 2.7? >> yes. >> it's 10.2. >> are you kidding? >> reporter: four times higher than farther downstream, not enough to kill fish, but they are more concerned about the overall impacts dredging could be having, impacts that currently aren't being measured. washington was among the first states to publish rules for small-scale mining in 1980. current regulations don't allow dredging during spawning seasons, and place restrictions on where in the stream miners can operate, how large their motors and hoses can be, and how close together they can dredge. but permits, which are free, are required only for projects that don't fall within these rules. this means that the state isn't tracking where or when dredging is taking place. that's a problem for mark johnson, a fish biologist with

the yakama nation. he says suction dredging can have a negative impact on fish- spawning habitat. >> when you get up in the isolated areas, people tend not to follow those rules. they will get into areas where it's smaller, coarse gravel, and that's typically where fish like to spawn. they dig their nests or their reds in the ground, lay their eggs and then they die. >> reporter: the nutrients from these dead fish build the food web for the next generation. miners say that current regulations are restrictive enough. >> if you are caught out here, you will get fined, and some of them are pretty stiff fines, up to $5,000 if you're not following the provisions. >> reporter: they contend their activities clear the streams of trash and debris, and have little to no impact on fish. >> a great many of the prospectors that i know are also fishermen, and none of us go up here looking to kill fish. >> reporter: angler and activist kim mcdonald says it's time for tighter controls and more oversight.

>> we will be able to see if there's any impacts from monitoring these guys, from having better enforcement. we will be able to see those impacts fairly quickly. >> reporter: caught in the middle is the state's department of fish and wildlife. they're responsible for enforcing mining rules. >> we receive a lot of pressure from both ends of the spectrum on mineral prospecting. >> reporter: deputy director jeff davis says that small-scale mining is on the rise, but more rules aren't necessarily the answer. >> part of the ecosystem are humans and their way of life on the land, and that has to be part of how our agency achieves our mission. i don't think you can regulate your way to long-term healthy fish and wildlife resources in every circumstance. >> reporter: back on the river, miner ron larson and his partner are shutting down for the day. >> let's see if we're getting any gold. >> ooh, yes, i believe it is.

>> wow. >> maybe a $40, $50 nugget. >> reporter: it doesn't pay for the gas to get here, but larson insists it's worth it. >> gold fever is a very, very real thing. it's-- it's an adrenaline thing, and it always keeps you coming back. >> reporter: as long as there's gold in these rivers, larson says, he will keep fighting for his right to search for it. for the pbs newshour, i'm nils cowan in seattle. >> sreenivasan: as the fighting in syria continues into its fifth year-- as the death toll grows, and cities are destroyed-- syrian artists, many of them forced to flee their country, have sought ways to respond. in recent months we've profiled a number of these artists in our online "art beat" series, "syrian voices." jeffrey brown has our look.

>> brown: a horror story told in one minute: that's the idea behind "fade to black", a short film by amer albarzawi, who shows us what's happened in syria through the changing image of farah brisly, an actress from damascus who now lives in istanbul. it's just one of the ways syrian artists have responded to the destruction in their country. in a refugee camp in lebanon, farah's sister, diala, has found another: working with syrian children, designing and painting murals with them to bring some color and joy to their lives. diala spoke to us by skype from her home in beirut. >> most of them, they skip school for two or three years, and they had to work in the farms to help their families. so they have really very, very serious life that doesn't belong

to a childhood, you know? >> brown: the work on the murals, she says, begins with a brainstorming session-- as she asks them to imagine what seems impossible-- like flying. >> i tell them, like you can use your imagination, it isn't supposed to be realistic. you can imagine anything. some of them, they think of butterflies, of birds, of air balloons, things like this. so after that i take this illustration and i get inspired by it and i start designing the mural and the day after they come to help me in filling the colors in the murals. >> brown: another artist-- a very different kind of imagery: waseem al marzouki documents the history of the syrian conflict through intricate, large-scale paintings and films that depict military and industrial images and symbols. he grew up near raqqa, now the stronghold of the islamic state, and now lives and works in los angeles.

he told us the war had left him unable to work for a two-year period. >> i was very shocked from what i see and what we have experienced. killing, displacement, torture, all this things happening to us. and after two years i start working again but i realize what i'm doing is totally different than what i have done before, it's more related to what we are facing. >> brown: another voice: that of poetry, which has always had an honored place in arabic culture. ghada al atrash is a syrian writer and translator earning a doctorate at the university of calgary in canada. >> syrian poetry today is an outcry. it is a plea to humanity. it embodies that human tragedy, that raw pain, the loss and the

defeat. >> brown: atrash is from sweida, in the south of syria, and has translated the work of najat abdul samad, a friend who remains in syria. she read us the beginning of the poem, "when i am overcome with weakness." >> "when i am overcome with weakness, i bandage my heart with a syrian woman's patience in adversity. i bandage it with december's frozen tree roots, trees that have sworn to blossom in march or april." >> brown: and then there is this, a documentary titled "the cow farm," about a farmer on the outskirts of salamiyah, syria. filmmaker ali sheikh khudr told us that when the revolution began, many rushed to capture protests and political upheavals. he decided to tell a different kind of story, one about hassan,

his own cousin, who supported the regime. khoo'-dur, a strong opponent, said he was after complexities, seeking to understand why people like hassan sided with the government. >> there's a lot of people, they just did not want to lose the things that they have. they did not want to lose their future, they did not want to lose their lives, they did not want to lose in the country itself, they were very afraid, they stood on one side against the other. on both sides you have people who are afraid. those people are afraid and the >> brown: khudr lives in berlin now. he says that above all, he feels a responsibility to share the stories of syrians whose lives have changed forever. >> the first responsibility was for me, that there should be a film, a documentary film, from syria telling something different, a new perspective, you know?

and there was also this second level of responsibility that i should take out this story. people who are dying in syria are not numbers, they are human beings and they have lives, they have memories, they have dreams, and that was lost. >> brown: for the pbs newshour, i'm jeffrey brown. >> sreenivasan: you can find much more on these and other artists in our "syrian voices" series on art beat at www.pbs.org/newshour. also on the newshour online: you've heard donald trump tout his "fine wines" in victory speeches, but what's really behind this luxury brand? we traveled to the trump winery in charlottesville, virginia, where we talked to visitors, who were interested in the candidate's politics, and his pinot noir. read more about our visit, and see photos, on our home page. all that and more is on our web

site, www.pbs.org/newshour. and a reminder about some upcoming programs from our pbs colleagues. gwen ifill is preparing for "washington week," which airs later this evening. here's a preview: >> ifill: we tee up a critical week in the 2016 election, as florida and michigan could shrink the republican field, and seal the deal for the leading democrat. the candidates turn to substance, talking about the middle east, trade deals and immigration, instead about each other. how refreshing. we'll talk about it all tonight on washington week. hari? >> sreenivasan: tomorrow on pbs newshour weekend, a report on babies born going through drug withdrawal, because their mothers were addicted to opioid painkillers and heroin during their pregnancies. and we'll be back, right here, on monday, with john yang's

report from the battleground state of ohio, ahead of their critical primary vote. that's the newshour for tonight. i'm hari sreenivasan. have a great weekend. thank you, and good night. >> major funding for the pbs newshour has been provided by: >> fathom travel. >> lincoln financial-- committed to helping you take charge of your financial future. >> bnsf railway. >> genentech.

>> and the william and flora hewlett foundation, helping people build immeasurably better lives. >> and with the ongoing support of these institutions >> this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. captioning sponsored by newshour productions, llc captioned by media access group at wgbh access.wgbh.org

>> this is "bbc world news." >> funding of this presentation is made possible by the freeman foundation, newman's own foundation, giving all profits from newman's own to charity and pursuing the common good, kovler foundation, pursuing solutions for america's neglected needs, and hong kong tourism board. >> want to know hong kong's most romantic spots? i will show you. i love heading to repulse bay for an evening stroll. it's a perfect, stunning backdrop for making romantic moments utterly unforgettable.