(00:00:15) The Great Lakes of superior, Michigan, Erie Huron and Ontario form the largest freshwater system in the world statistics surrounding the lakes are staggering one-fifth of the US population and one-fourth of all us industry are situated within the Great Lakes Basin over 4,000 miles of Shoreline link the eight states, which border the Lakes steel and paper mills Wineries and mining companies are situated along the shores as are some of the country's largest cities 65 trillion gallons of fresh water. That's 95% of the drinkable and navigable water in the United States is found in the Great Lakes. Needless to say these five freshwater lakes are a very valuable natural resource for this. Agent and for the country as well, however, the Great Lakes as valuable as they are have been trouble lately take Lake Erie. For example, a mere decade ago. Erie was a National Disgrace the portions of the lake that weren't covered with an oil film had thick formations of algae growing on it this growth spurred on by various pollutants including phosphates in laundry detergents fish in the lake floated belly side up and beaches were regularly closed along the shores this type of neglect eventually focused attention on a resource that too many persons had taken for granted for too long a period of time during the Nixon years in 1970. The Environmental Protection Agency was established by executive order the EPA seem to be the logical Federal agency responsible for the Great Lakes as a consequence billions of dollars were set aside to assist towns and cities build modern sewage treatment facilities and to give industry in the Great Lakes Basin a hand with waste treatment seven years after The Environmental Protection Agency was established. The Great Lakes National program office was set up this program office located in Chicago is responsible for shaping and implementing policy designed to help the EPA with a huge task of cleaning up the Great Lakes. The cleanup tasks is not just an American Headache Canada has for a long period of time used and abused the lakes and much the same manner the US has fortunately the two countries have been able to work in sync to try to alleviate some of the difficulties plaguing the Great Lakes system. The earliest joint recognition of the problem was in the early 1900's in 1909 Canada, and the United States signed a mutual Boundary Waters treaty, but it wasn't until 1972 before another agreement was reached six years later in 1978. The present water quality agreement was signed between Canada and the US this current agreement surpasses previous treaties between the countries by dealing more effectively with pollution from sources other. Then direct discharges into the Lakes including air pollution and agricultural runoff. The recent treaty also sets definite limits for radioactivity and various toxic substances such as polychlorinated biphenyls pcbs for short pcbs were developed in the 1930s and they are used for changing characteristics of certain Plastics and most importantly they're used to conduct and transfer heat in and out of large electrical Transformers and capacitors. Thereby preventing explosions, but lately research has shown that pcbs are carcinogenic Lake Superior is by far the deepest and for all practical purposes the cleanest of the five lakes, but even Superior has not been able to escape PCB contamination already a major threat to Lake Michigan PCB contamination of the Great Lakes poses a special threat to the water quality of the system scientists suspect the transmission of pcbs through the air is the most likely source of the contamination in fact up to 95. Percent of the PCB pollution in the lake is carried through the air in order to track the course of PCB pollution and other toxic chemicals in the Great Lakes. The research vessel crackit is used the crackit wants a deadly Navy gunboat is now a 165-foot floating research. Laboratory. The Crockett is now in her second year of intense water quality monitoring of Lake Erie every year or two The Vessel will move to a different Lake and conduct extensive research eventually covering all five Great Lakes recently. The RV Crockett was on Lake Superior at the request of three University of Minnesota scientists working with the EPA to answer important questions concerning Superior such as where do the contaminants like PCB circulate in the waters. And where do they accumulate? Dr. Steven eisenreich is an associate professor of environmental engineering at the University of Minnesota eisenreich has investigated numerous environmental problems, and is one of three. The scientists currently studying Lake Superior. Well, (00:05:02) we have a wide variety of research going on. The there are two aspects that are being investigated on this Cruise. One of them is the cycling of pcbs in Lake Superior in the air and in the water and in the sediments and looking at the sedimentology or the rate of sediment accumulation in the lake and the other aspect of the work, it is being performed by dr. Michael Cider at the union from the University of Minnesota Duluth was looking at remote sensing with satellite overpasses to look at contamination and movement within the lake what percentage of the pollutants in Lake Superior come from say the air. That really depends on the type of pollutant. But the in terms of pcbs, we think well over ninety five percent comes from the are some Trace metals like which are quite toxic to to the ecological system like cadmium and zinc and a few others anywhere between 40 and 70 percent from the atmosphere. I like superiors the cleanest of the five Great Lakes and deepest also but but what what are some of the major problems the lake has that's very difficult problem. Why don't one of our research objectives is to identify some of the contaminant problems in Lake Superior because if not has not been investigated to such a great an extent as the other Great Lakes one of the problems we have identified and are presently working on is the movement of pcbs in the system. Not only how much is entering the lake but how its partitioning between various of the portions of the ecological (00:06:50) compartments one of eisenreich Scott. Exist, dr. Thomas Johnson assistant professor of sedimentology at the University of Minnesota (00:06:58) right. Now. The most important thing is finding out more about how the lake operates as a system. There's an awful lot of unknowns involved in knowing how the water circulates in the lake to what extent there are strong currents flowing over the lake Bottom productivity in the lake. We don't really know where the high productivity areas are in the lake and where the low productivity areas are. We have some ideas, but we really haven't pinned down some of these very basic questions about this particular Lake environment. I would say that there's you know, there will be scientists coming along for another hundred or two hundred years that always have very important questions to ask and to answer I think that well, we've been working on the lake now for three years and we've answered some questions and we see more questions coming up all the time. I would say that some of these basic questions could some of the very fundamental questions could be answered within the next 10 years, but I don't think that at the end of a 10 year period of time that we could say, well we know everything that we should know about Lake Superior. Let's move on to some other (00:08:17) environment doctors Johnson and eisenreich along with a handful of other researchers are literally using the Crockett to wage war against pollution in The Lakes apparently successfully a commercial fisherman out of Duluth Minnesota comments that he no longer picks up oily Globs in his Nets and on the Eastern Great Lakes. The change is visible to the eye but it's not just the visible pollution which worries the experts unseen pollutants like PCB are literally dangerous even in small quantities. And even though certain pollutants may be of a local Source eventually most contaminants find their way into the entire Great Lakes system. So whatever pollutes Lake Superior will to a certain extent pose a problem for Lakes, Michigan and Huron possibly. Even Erie and Ontario and vice versa. So that none of the Lakes is an independent ecosystem from the others taking this into account. It's not surprising concern for the health of one Lake compared to the others runs high among the researchers for a closer. Look at what happens on board the RV Crockett during a research run what better way to find out then to go on board. The deck of the Crockett is packed with various measuring and calibrating tools. Dr. Tom Johnson describes, the various devices and their uses on the windy deck of the crackit. (00:09:34) These instruments here are basically electronic thermometers. We call them electronic Bethy thermal graphs. That means they measure the temperature of the water at different depths in the water column we have Of this probe right here, and we have another probe under that canvas that does a similar thing. We put the probe in the water and lower it on this cable. The cable has electrical conductors him. And as this is lowered down through the water column. It is constantly sending the temperature of the water up the cable to our recorders. So we immediately get a graph of temperature versus steps on it Lake superior's what over 1,300 feet deep and certainly the deepest spot is about 1,300 feet. How far down do you go with these things? We've been working in depths as great as 350 meters, which is what about a Thousand Eleven Hundred feet. This device here is a seismic reflection profiler. Well, we're underway between stations. We're Towing this at a depth of about 30 feet. It's basically for transducers inside a plexiglass shell and it emits a low frequency sound. Goes down and reflects off the lake Bottom some of the sound penetrates the lake floor and reflects off sediment layers beneath it again. This is towed by a cable which has electrical conductors in it. The signals are then sent back to our lab back aft where we have a Graphic recorder, which then gives us a nice graphic display of the shape of the lake bottom and the shape of the sediment layers beneath the lake floor with this system. We can penetrate about oh 250 feet of sediment and see the structures in the sediments that way it's a very useful device for telling us our remote sensing device for telling us what we should expect to find when we lower a sediment sampler down to the lake floor that is whether we should expect to find gravel or sand or mud or Rock. This device here is a gravity core. It's basically a steel pipe with some lead weight at the top of the pipe. This is our primary sediment sampling device at well. It has been for the first half of our Cruze for the second half of our crews from Duluth to the Sioux will put on a large box coring device which brings up much larger samples. This gravity core has a pipe on it that's about 3 inches in diameter and it's about 8 feet long and we lower this down to the lake floor the pipe penetrates into the mud and when we pull the recover the core or pull the pipe back up to the ship the mud stays in the pipe once on board ship we can extrude the mud and then analyze the mud for various parameters to say if the if the chemicals or whatever settles into the sludge at the bottom, especially in the harbor areas and the core goes through and does some dredging but that dredging actually stir. Some of these pollutants. Do you know anything about that? Well, yeah, I know something about it anytime the you're injecting contaminated materials into this Lake you have to be extremely concerned about what effects that contaminated material will have on the environment and whether whether the amount of harm done by the injection of these contaminated sediments poses a serious problem to the lake or not is the major question that has to be asked clearly. It's going to cause some harm and then the question is how much farmers are going to cause we lower most of our sampling devices on our gravity core or our water sampling bottles, which I haven't shown you yet. This is the way we put them down most people think that oceanographers and people who study Lakes are divers and that everything that's done is done with a SCUBA tank on the back and that's not the case. Most of the sampling that's done is done from a stable platform from a ship some of us dive, but we generally die for fun and not and it's not professional diving at all. This is where we have our graphic recorder for the seismic reflection profiling system. There's a fair amount of Fairly sophisticated Electronics involved with the system. And so we have to have some Electronics expertise along with us when we're out. We're constantly keeping track of the navigation back here in the lab as the ship is under way and we have contact with the bridge with a portable radio here and much of the direction of the ship takes place back here in this lab. We tell the bridge when we want to turn and what direction we want to go next and so that we can get maximum amount of information with our seismic year when traveling from one station to another (00:15:01) To collect the water samples from the lake the researchers lower a hollow container into the water to a precise depth trap the water and then lift the container back on (00:15:10) board. We have to take a very large sample in glass because the levels of the contaminants are very low and we have to isolate the material in 20 liters or about 5 gallons into a very small quantity. Very small volume. So that the our analytical instrumentation back in the laboratory can measure (00:15:35) On board the Crockett our student researchers as well. Brian Looney is one of the interns who came to explore the Great Lakes from Texas Bryan describes his duties in the wet lab, okay here in the (00:15:46) upstairs wet lab. There's a two groups of people in here and I'll just describe what our group does. We're analyzing for Trace Organics. You saw us take the sample out there a minute ago in this glass jug, it's 20 liters and now we're passing the water through a polymer bead bed. It's a bed of resins called xad to resins and their selective for the types of compounds that were interested in these are pcbs and those types of Organics that come from man. There's a filter in the different contaminants cling onto the resins. In other words. The the water that comes through just goes to waste in the resins then have theoretically to some degree collected the the Organics that you're interested. To them and then you do studies to make sure that you're getting the proper recoveries and things like that and you have to adjust your flow rates and bed size to those requirements. It's very the reason that we use that big bottle out. There is for only one reason to get this large sample. Another reason is it's Teflon lined and that's another normally these small sample bottles are plastic and PVC and if we took a sample in a PVC container, then it would be contaminated by the Organics that leached out of the bottle of just in the short time that it was in there. So that's basically what we're doing we run the water through here at the proper flow rate. And then we transfer these resins into a small glass jar with hexane and acetone which are just organic solvents and then take them back to be analyzed by gas chromatography in the laboratory anything peculiar about Lake Superior that you're finding out through this type of study with the water. Well Lake Superior is a fairly pure. And what makes it interesting for this type of study is that there's not very much around here. And so most of the Organics that are put into the environment are come from the atmosphere. So it's a it makes a good study area for a looking at atmospheric deposition two lakes, and then we can look at the sediments and the sediment profiles and see how the atmospheric deposition has changed with time things. Like this it I don't know. I personally think it's interesting because it is the got the largest surface area of any freshwater lake and so that's just pretty exciting for me to be able to work out here. So I'm from Texas. No (00:18:11) wonder dr. Michaels side or is Professor of physics at the University of Minnesota Duluth site or is utilizing satellite data in order to study dispersal of pcbs and other Lake Superior contaminants. He is coordinating data from the new water specific nimbus-7 satellite, which was launched in October of 1978 and programmed for one year studies of the world's Waters. I'm out of every six days nimbus-7 can take pictures of the Great Lakes. These pictures can relay information about the surface water temperature and they can also indicate Waters that are clear which appear as blue or heavily sedimented shown as brown on the satellite pictures. Dr. Site or explains his post on the (00:18:51) Crockett. This area is a place where we did our staging for measurement of currents and we set out our to current meter stations already out on the lake. So there are no currents here right now. This is also the area where we keep some of the records this machine takes the record of transparencies and BTS. This one records the electric field data with the mill over there. So this generally this room is a prep room for us and and a place where we keep all our recording equipment. (00:19:30) Although research on the Crockett is progressing smoothly. It's still too early to be completely optimistic about the future of the Great Lakes toxic substances such as pcbs continue to pose threats and these require new scientific standards for understanding and controlling the chemicals that continue to multiply in society States would share the epa's responsibility for cleaning waters are doing their part those that have banned High phosphate household detergents. For example note hopeful signs of waters. No longer choked with algae. There are further improvements gone are some of the highly visible signs of pollution Industries and local governments have made considerable strides forward and cleaning up their waists. Clearly the Great Lakes needs more research like that done with the RV Crockett because it's obvious America needs the Great (00:20:18) Lakes on 16. This is a crocodile.