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UNITED STATES DISTRICT COURT
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UNITED STATES OF AMERICA, et al.,
vs. SOUTH FLORIDA WATER MANAGEMENT DISTRICT, et al.,
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| Miami, Florida November 9, 1995 |
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| TRANSCRIPT OF HEARING PROCEEDINGS IN THE
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APPEARANCES:
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3
Reported By:
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MORNING SESSION
not have Dr. Jones this morning, and so we will again I think we agreed with one of our your witnesses?
before I had left for Judge Highsmith's hearing, we had had this conversation with counsel, and it does make sense to the Miccosukee Tribe, they have out of town witnesses, and so forth.
those that Hour next witness was Mr. Duncan, and it makes some sense to take these witnesses. Mr. Duncan lives here, but we just again are somewhat concerned that it be understood that Mr. Duncan is still there.
the 28th. If he could be done today, that would be fine.
happened with these experts, it may be that that residual time when Mr. Jones comes back is when Mr. Duncan would have to testify as well.
5 everyone that that wasn't said yesterday just because I was in Judge Highsmith's court.
record, I would like to re-move to strike additionally Dr. Jones' testimony in the event he does not face cross-examination.
cross-examination.
call Dr. Michael Mocina to the stand, please.
there. MICHAEL JOHN MACEINA, Ph.D, SWORN AS A WITNESS, WAS EXAMINED AND TESTIFIED AS FOLLOWS:
your last name.
DIRECT EXAMINATION BY MR. GREEN:
6 Direct-Green-Maceina
Q Good morning, Dr. Maceina. A Good morning. Q Would you briefly describe your educational background? A Yes. I have a Bachelor of Science Degree in Wildlife and Forestry from the University of Florida, a Master of Science Degree in Fishery Biology from the University of Florida and a Ph.D in Fishery Science from Texas A & M University. Q Please briefly describe your professional experience since completing that formal education? A After I finished my Ph.D in 1987, I was hired as a senior environmentalist for the South Florida Water Management District. I worked for the Water Management District for 3 years. I am currently at Auburn University. Q And what is your position at Auburn University? A I am associate professor. Q Are you currently teachings cources there? A I teach two classes. Q What are they? A One is in fish population dynamics. The other one is in statistical applications. Both of those are graduate level classes. Q And what sorts of subjects do you apply your statistical applications to, just briefly? A Of course, mostly the fishery data, but a lot of it is
7 Direct-Green-Maceina
applicable to any type of natural resource field. Q Now, Dr. Maceina, I would like to read some sentences to you from -- Your Honor, this is the memorandum in support of the motion of the United States for partial summary judgment on liability filed in this case on November 19, 1990.
statement to you, if I could, Dr. Maceina. It starts, "WCA-2A wetlands receive a particularly large supply of nutrients through the S-10 inflow structures, which transports drainage from the Refuge, because of the large canal system which converges on these structures and because of their proximity to the EAA."
A I agree with that statement.
The federal claims have been settled. They are not being tried. I am not you sure I understand the relevancy of the questions about the merits of the United States' summary judgment motion.
testimony. We are just trying to reference -- if you will bear with me for about two more minutes, we are trying to get into the issue that Dr. Jones raised very briefly.
please.
8 Direct-Green-Maceina
supply of nutrients through the S-10 inflow structures, which transport drainage from the Refuge, because of the large canal system which converges on these structures and because of their proximity to the EAA."
statement?
the citation after that sentence and then read the next one, Your Honor.
absence of interior canals in WCA-2A forces this water to flow across the marsh where nutrients accumulate in the marsh through a corporation by marsh soils and vegetation eventually saturating the system and moving farther and farther downstream."
BY MR. GREEN: Q When you say, "That is correct," I am asking you did you you hear Dr. Jones' testimony yesterday? A Yes, I did.
9 Direct-Green-Maceina
Q Can you tell me whether this statement reflects the testimony you heard yesterday, whether or not -- A It agrees with the testimony of Dr. Jones.
didn't testify at all about conservation area 2-A.
that nutrients accumulate in the peat if the phosphorus levels are raised above ten parts per billion; that the peat becomes saturated; that the system is destroyed, and that the nutrients just keep moving.
Dr. Jones who, by the way, is referenced here as Jones Declaration at paragraph 14 back on this page 28. That's the theory basically he expoused yesterday.
his general understanding, not to water conservation area 2-A.
BY MR. GREEN: Q Now, Dr. Maceina, when you were working with the Water Management District, I think the dates you described that since you left was back in 1990, is that correct? A That is correct. I left in June of 1990. Q Okay. But before you left, in your responsibilities for
10 Direct-Green-Maceina
the District, were you asked to undertake any work to analyze data in water conservation area 2-A to determine whether those data supported or did not support the moving nutrient front theory? A In November of 1989, I was asked by the District to assemble all the water quality data that had been collected by the District from 1976 through September of 1988 to analyze the nutrient front gradient that appeared to be apparant in water conservation area 2-A.
made. My expertise is statistical analysis. They wanted me to statistically analyze the data to verify if that, in fact, was true. Q Did you conduct such an analysis? A Yes, I did. Q When you conducted that analysis, can you tell us whether you used standard and approved statistical techniques? A Yes, I did. Q Thank you. Dr. Maceino, I am going to show you a document that has been pre-marked defendant's exhibit 86 and ask you if you can identify it? May I approach the witness, Your Honor?
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BY MR. GREEN: Q And what it is it? A This is part of the SWIM Plan for the Everglades that was published in March of 1992 and pages 166, 167 and 168 reflect the results of my analysis that I conducted and held in early 1990. Q Okay. I would like to refer you, if I could, to page 166, and there is a third paragraph down with an underline under it.
perimeter marsh." Do you see that paragraph? A Yes. Q And would you review that, the first two sentences of that paragraph briefly that follow the title. A Yes. That is what I found. Q Okay. So you agree? A I agree with It. I agree with those two statements. Q Okay. Now, let's turn to page 167.
sentences are you referring to?
I was trying to save time. I apologize.
Everglades WCA's during the late-1970's and early 1980's indicate that major water quality changes have taken place
12 Direct-Green-Maceina
downstream from District water controlled structures within WCA-CA-2A. The discharge of nutrient enriched canal water across the northern portion of WCA-2A has resulted in a nutrient gradient of decreasing phosphorus concentration downstream of the S-10 down stream discharge structures." Do you agree with those two sentences? A Yes, I do. Q Now, if I could ask you to go to the next page, Dr. Maceina, and refer you to what is labeled figure 29 there entitled, "Comparison of Average Total Phosphorus Concentrations Downstream of the S-10-C, 1978-1979 and 1985- 1996."
data that underlie it? A Yes. I didn't construct this plot, but the data that was given to me while I was employed at the District, I went ahead and analyzed this data, and essentially came up with the same type of schematic that's presented in figure 29. Q Do you agree with its basic depiction? A Yes. What I did essentially was do statistical analysis on that data, basically looking at the differences in phosphorus as you move from south -- from north to south and essentially determined if those differences as you see in 195, 1986, which appear a lot higher, are significantly higher than the base line period of 1978, 1979.
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Q Can you tell us which way north to south goes on thishorizontal axis? A Sure. North is at zero. That's essentially the location of the S-10 structures, the S-10-C, and then going south into water conservation area 2-A down to about 11.3 killometers, which is the 217 gage. Q I want to be sure I understood what you said. What does this lot compare to? What time period? A This time period compares 1978, 1979, which was a period where a lot of data was collected in area two and compared phosphorus concentrations to 1985, 1986 essentially in the same distance areas south of the S-10-C. Q Okay. Now, let's turn to the next page, please. The second paragraph, the last sentence, and I will read it.
observations that nutrient levels having increased downstream of these water control structures over time" -- citations omitted -- "and that a "Nutrient front" has progressed further south into WCA-2A during the 1980's."
discussed so far in the SWIM document, do you agree with that conclusion? A Yes. That conclusion is true.
Maceina as an expert in equatic biology, including the
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analysis of environmental data to discern transient water chemistry.
will be received as an expert in that area.
BY MR. GREEN: Q Dr. Maceina, I hand you what has been marked as exhibit 7 and ask you to please identify it.
86. I assume you are offering that?
like to go ahead and offer 86 while we are here.
BY MR. GREEN: Q What is that, Dr. Maceina? A This is a document that I submitted to Mr. Gary Perko who is an attorney with your law firm. It is an update on looking at changes in total phosphorus in water conservation area 2-A, using data now all the way through September of 1994. Q I would ask you to look at page 1 of this document and just read outloud the second and third sentence in that
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page, please. A "There is absolutely no evidence that the phosphorus front has moved further south from the S-10 structure since 1978-'79 due to anthropogenic loading from the upstream basin. In fact, the reversal of the process appears to be occurring." Q And read the next sentence, too, please. A "Total phosphorus concentrations. TP concentrations continue to climb in 1994 from 1995, '86 and 1991, '92." Q Is that your opinion? A Yes. Q Now, how did you reach that opinion? A I was able to gather data from 1989 through 1994. Most of the data was collected by the South Florida Water Management District. I re-analyzed the data, compared it to the results that were collected during the base line period of 1977, '79. Q And in the interests of time, Dr. Maceina, can you come up and just point out on the chart the evidence that supports your opinion? A Do you have a pointer? Q First, I would ask you to identify this demonstrative aid which is labeled figure 1. A Figure 1 one is the document marked in evidence as 87. Q And what does that show, Dr. Maceina?
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A This is analogous to figure 29, which is evidence 86. Here is the base line period 1978, '79. Here is your different distance zones coming south of the S-10-C, so this is the northern portion of WCA-2.
very, very high total phosphorus concentrations in '78, '79. It declined rapidly. Here is the period of '85, '86, which is also that data is presented in figure 29 and evidence 86.
relatively similar to those measured in '78, '79, but now in '85, 86, they are much, much higher than they were in '78, '79, indicating that the nutrient front has moved further south.
analyzed 1991, 1992. The same phenomena is apparent. You see now a decline in total phosphorus concentrations, and levels have essentially dropped essentially to the background levels that were measured in 1978, '79. So, there is still a gradient that exists in the marsh. However, that front is now the same as it was in 1978, '79. There is no evidence right now to suggest that the nutrient front has moved further south. Q Dr. Maceina, does this analysis support Dr. Jones' theory about the moving nutrient front? A No, it does not. It contradicts it, and Dr. Jones
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probable ideal SWIM Plan, but based on the latest data analysis, there is absolutely no statistical evidence to show the nutrient front has moved further south.
from decade to decade? That is, you show, for example, the experience -- I forget which line. It is the larger broken line.
pretty well downstream.
lesser contribution. What has happened to the concentration that existed in 1985?
system, and I believe it is primarily regulated by internal forces, and that when the marsh gets low, dries out phosphorus is re-memoralized out of the soil and comes back in the water column.
back down into the soil. And the one thing to remember is that this marsh has operated essentially as a lake for 20 years. When the new regulation schedule was put in effect
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in 1981, we went back to a normal wet-dry cycle, and phosphorus concentrations were extremely unstable in the marsh for 10 years, and now they appear to be stablizing.
what has happened to the phosphorus concentration that existed in '85?
or destroyed. A lot of this phosphorus has probably now settled back down into the soils.
biodegrade?
the peat soil and into the plants.
the entry point in different levels, it doesn't accumulate?
understanding why in '95 it would be so much less than in '85 and before.
BY MR. GREEN: Q Where does it accumulate?
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A It accumulates in the soil. In many cases it accumulates in the soil that's no longer available.
testing the water.
water. You asked me where the phosphorus went. It went into the soil.
water problems? Does it come back up again as you suggest?
hydroperiods in the Everglades, and all, and it remains to be seen, and certainly this needs to be examined over time, but since 1991, it appears that the phosphorus concentrations have declined and we are --
phosphorus continues to build over time, no matter what kind of system you have. The question is are we in a more stable type of situation right now?
the state analysis, that the nutrient front is moving further south.
Direct-Green-Maceina
BY MR. GREEN: Q Do you have another poster just while you are up here? A Yes. I analyzed the data lots of different ways. This is below the S-10-C. I pulled the data for all the S-10's. I looked at many different time periods that are listed in exhibit 87. Q What figure? A I am sorry. This is figure 2 in evidence 87. If we take a look at '83, '84, it is two years after the new regulations schedule is put into effect. There is very, very high phosphorus concentrations, declining, and now when we look at 1994, we see that we are much lower, particularly close to the S-10 structures. Q If I may ask a leading question? Is this a 10 year period? A This is essentially a 10 year difference. Q Okay. Now, Dr. Moceina, did you hear Dr. McClave and Dr. Goforth yesterday testify that in general the data seems to show the Loxahatchee phosphorus measurements are back to the levels of 1978 and '79? A Yes. They appear to be at the some base line levels. Q Would you agree with their conclusions? A Yes, I do. Q Why?
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A Why? Because water flows to the Loxahatchee marsh, and if it flows to the Loxahatchee marsh and it has remained unchanged over this let's say 15 year period of time, there is no reason to believe it has reremained unchanged in area 1 that it should not remain unchanged in area 2. Q Do you have an opinion on whether the phosphorus front, if you will, south of the S-10's is back to the same way it looked in 1978, '79; whether it is or not? A Could you restate the question again. Back to the same levels. It is lower. It is lower right below the S-10's in 1994 then it was in '78, '79. Other than that, the concentrations are basically the same; '78, '79 as they are in 1994. Q What is the source of that water? A The source of that water is from area 1. Q So, because that's a source, does that give you any additional information one way or the other on whether the Loxahatchee has returned to the '78, '79 levels? A Yes. I mean, that is what the data showed that we saw yesterday, that it returned to those levels. So, if it appears to be the same or it is the same in the Loxahatchee, there is no reason to believe that it is not the same in area 2.
for cross.
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to begin?
first, please?
will receive 87.
down here, Mr. Lehtenin?
CROSS-EXAMINATION BY MR. LEHTINEN: Q This is just based on or this is based upon data that the Water Management District has? A Yes, that's correct. Q And let me show you or let me ask you about, you think this phosphorus was not destroyed. The 1985, 1986 phosphorus is still somewhere there, right? A For sure. Q It is just not shown in this data? A It is not shown in the water column. Q Right. Isn't that part of the problem, that the phosphorus goes into the soil? A Well --
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not been defined. BY MR. LEHTINEN: Q Well, let me ask you this: As the expert that you have been, I didn't object because it sounded okay when Mr. Green said an expert, but I wasn't sure what it was, to tell you the truth, but I was willing to let you testify,
opinion about the effect that that phosphorus being in the soil will have on the Everglades? A I have no opinion on that. Q Okay. So, then, let me show you the draft impact statement from the Corp of Engineers. On page 123 -- this was passed out many times, Your Honor. Do you you see that open there?
used it before.
this may be much ado --
BY MR. LEHTINEN: Q That is a map that purports to show phosphorus influences at various discharge structures in or around canals, is that correct?
24 Cross-Maceina-Lehtinen
question, Mr. court reporter.
Lehtenin. BY MR. LEHTINEN: Q Does that map purport to show or the heading shows phosphorous influences around canals and discharge structures? A That is what the label says. Q Perhaps it is out of your area to lead you into that. Do you have an opinion about whether phosphorus could cause those influences that are shown on the map?
broad question. This witness has been offered to give a statistical analysis of water quality data south of the S-10 structures for purposes of testing the moving water column nutrient hypothesis. This goes beyond the scope of his testimony. BY MR. LEHTINEN: Q So let me ask you this: We may be establishing what I want to drive at. What effect the phosphorus has is outside of your area of expertise? A No, I have looked at a lot of the data that's out there, and phosphorus certainly has an affect on plant
25 Cross-Maceina-Lehtinen
growth. Q Okay. Is that a little bit different than when you testified earlier, and I asked you what happens if that phosphorus is in the soil, or let me ask you that, based on your answer.
which is not in that water column now, what would the effect be if it went into the soil as you said it might have done? A It all depends on the bioavoilability of that phosphorus, which I can't really answer.
questions, Your Honor.
sit down. CROSS-EXAMINATION BY MR. SEARCHINGER: Q Dr. Maceina, you would degree, wouldn't you, that phosphorus is continuing to come through the S-10 structure at a level above background concentrations, is that correct? A Nobody has ever measured background concentrations, so I cannot answer that. Q Okay. But would you agree that the phosphorous coming through the S-10 structure is higher than the phosphorus downstream of the S-10 structure in the water column?
26 Cross-Maceina-Searchinger
A That is correct. Q Do you have an opinion on what is stopping the expansion or what is taking up the nutrients on the way down from the S-10 structures to that lower area?
that same question, I believe.
opinion what is taking up the --
phosphorus? What is preventing it? Essentially, what is preventing that nutrient from expanding.
will take it up. Sometimes you have direct precipitation of phosphorus in the soil, and then plants will take the phosphorus. BY MR. SEARCHINGER: Q Would you agree that the fact that that zone is already impacted has significance for how it is taking up phosphorus?
impacted. It is a very general question.
ahead. BY MR. SEARCHINGER
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Q Would you agree that the area south of the S-10 structure is high in phosphorus in the sediment and has a lot of cattails in it? A That's true. Directly south of the S-10 area the water is relatively high in phosphorus compared to the rest of the Everglades, and it does have cattail in it. Q Do you think that has anything to do with your theory that it is blocking the nutrient expansion?
repeat the question. I think you will see it. BY MR. SEARCHINGER Q Do you have an opinion on whether or not that cattail and nutrient enrichment is slowing the rate of or blocking the rate of or blocking nutrient expansion? A I think any type of plant life emergent plant life and associated microbes would also cause a decrease in phosphorus concentrations. Q Now, did you hear Dr. Jones testify that the northern end of conservation area 3-A is relatively pristine from the standpoint of phosphorus yesterday? A How do you define pristine? Q Has low phosphorus concentrations in the sediment water. A Yes. Q What do you think? Now, you heard that Mr. Gherini recommends or proposed a plan that would move the phosphorus
28 Cross-Maceina-Searchinger
into that area directly from the EAA instead of having the phosphorus go through the impacted area south of water conservation area 2-A.
mischaracterizes the testimony. Mr. Gherini showed what the implementation of the Everglades Forever Act plan would show when you spread phosphorus into the northern areas. In fact, I think there is a chart still up there that shows the EFA plan.
simulation, what effects that would have. He made no proposals.
Your Honor. He was recommending it.
BY MR. SEARCHINGER: Q Do you have an opinion on what is likely to happen in terms of expanding nutrient front if water is coming in to the top, now this pristine area in top of conservation area 3-A? A Well, I have shown there is no expanding nutrient front. Q You have shown there is no expanding nutrient front in 2-A? A I have not analyzed data in 3-A, so I can't give you any
29 Cross-Maceina-Searchinger
opinion on it. Q Do you think it is possible that there may be a different impact of moving water through an area that's already filled with cattail and has high phosphorus in the sediment, that in putting it in an area that doesn't have cattail and has low phosphorus in the sediment? A I can't speculate on that. Q Okay. Now, your testimony, as I understand from looking at your chart, you are comparing, all you are comparing is data from '83, '84 and '78, '79 with data from 1994, is that correct? A If you take a look at all the figures that are in that exhibit, 87, as well as the table, I have made multiple comparisons over time which all show the same trend. Q Have you made any analysis of whether or not phosphorus is or have you made any analysis of whether or not there is an expanding nutrient front in the sediment in water conservation area 2-A? A No, I have not done that. Q You heard Dr. Jones testify that what impacts the micro-organisms and the macrophytes is phosphorus enrichment in the sediment. Do you have an opinion on that statement? A No, I don't. Q Would you agree that the actual phosphorus concentrations in the water column depend in part on whether
30 Cross-Maceina-Searchinger
or not we are in a high rainfall or low rainfall year? A I've done some other analysis, and there is no relationship at all between phosphorus loading or phosphorus concentrations coming through the S-10's. Q That's not my question. A I am sorry. Q Phosphorus --
answer, please, counsel.
this, and this is an analysis I did while I was at the District. There is no relationship at all between the phosphorous concentration coming in or the phosphorus load coming into the S-10 and total phosphorus concentrations in the water column in area 2. BY MR. SEARCHINGER: Q Okay. What about the relationship between how much rain is falling on area 2 and how much water is in area 2 and concentration in the water column? A Typically, when water levels are high phosphorus, concentrations decline. Q Was 1994 a high water year? A I haven't seen any staged data, but from talking to people, it seems like it was a very wet year in South
31 Cross-Maceina-Searchinger
Florida, so I assume that it was. Q Isn't it possible that we could be seeing significant fluctuations in the water column phosphorus concentration and yet have an expanding sediment nutrient front? A I can't speculate on that because I don't have any data. Q Okay. Do you know how long it takes sediment to absorb water from or absorb phosphorus from the water column? A That depends on a variety of chemical and biological factors. Q Would you agree that in some cases it can take minutes? A Sure. Q So isn't it possible that an area could be receiving, let's say an area down at the bottom end of this nutrient gradient, that that could be receiving phosphorus that is rapidly absorbed into the sediment and then reveals a water column concentration that isn't all that high? A That's possible, yes. Q Do you have an opinion on whether sediments can become saturated with phosphorus? A I have no opinion on that. Q Okay. Have you ever heard of sediment saturation? A Yes, I have. Q What does it mean? A Like I say, I have heard of it, but I am not knowledgeable in soil dynamics, phosphorus dynamics in soils
32 Cross-Maceina-Searchinger
to state an opinion on that. Q Okay. Now, doctor or Mr. Gherini testified that there was a higher settling rate of phosphorus closeer to the EAA than there was of a settling rate for phosphorus as you went down through water conservation area 2-A.
the opposite of what Mr. Gherini testified to.
lower settling rate of phosphorus in the area immediately just below the EAA and a higher settling rate as you went down. You are right. I apologize. I misspoke. BY MR. SEARCHINGER Q Doesn't that evidence suggest a standing nutrient front? A I can't comment on that because I am not a phosphorous dynamics modeler. Q Okay. Do you have an opinion on whether or not the plant, that the cattail community in water conservation area 2-A is likely to be more or is more likely to return to a sawgrass Everglades community if phosphorus continues to come in that area at the existing concentrations through the S-10 structure? A Based on my analysis and my observations in water conservation area 2-A, I believe the hydroperiod is the most dominant factor. When I was out in the marsh in 1989, right below the S-10 structures, sawgrass was reappearing in
33 Cross-Maceina-Searchinger
conservation area 2-A, but yet you had phosphorus concentrations in the water columns of 4 to 5, 600 parts per billion. Extremely high. Q So you do have an opinion on what causes cattail in the marsh? A Yes, I do. Q Are you aware of Dr. Jones' work which shows that or I think he said 99.9 percent correlation between the existence of cattail in the marsh and elevated concentrations of phosphorus in the southern?
heard Dr. Jones testimony, but there is no data in evidence to support any of that.
a published paper on that.
I would be interested in seeing it. It doesn't surprise me, based on previous analysis. The problem with all this, and this has been brought up before, is that tigh phosphorus concentrations in the soil, high water column phosphorus concentrations coming from inflows is highly correlated with hydro-period. It is also highly correlated with sodium Choride.
34 Cross-Maceina-Searchinger
doctor?
inundation. Essentially, if a wetland is covered through January through June, there is a hydroperiod of 50 Percent, and in the case below the S-10's, it is nearly a 100 percent hydro-period which favors the growth of cattails.
building of the L-39 canal, that area is a lot deeper. It has been a disturbed area. The deeper water, along with the the high hydroperiod, in conjunction -- I believe there is an inner action going on here with nutrients, and that this is why you have cattails there. 3 factors. Hydroperiod, disturbance, and to a lesser extent, nutrients. BY MR. SEARCHINGER: Q Do you agree that there are areas that have cattail in interior portions of the marsh that have no different hydroperiods from the areas adjacent to them? A The areas that I have seen in the interior of the marsh tend to be slightly disturbed areas or lightly deeper areas. Any place you go pretty much through the Everglades area, the Everglades protection area where there is a canal that's been dug or a ditch that's been dug, you always have cattails which correspond to deeper water. Phosphorus concentrations can be as low as ten parts per billion in those areas and still contain cattails.
35 Cross-Maceina-Searchinger
Q And isn't there a deep water area at the bottom of water conservation area 3-A? A Yes, there is. Q Is there cattail are? A Yes, there are. Along the canal there are. Q What about in the large pool that extends up through the water conservation area? A They have not been exactly along that area. I don't know how for they go back. In area 2 they go back about half a mile from the canal. Q In the canal. You don't know if they go back -- A I don't know how far they go back. Q It is an extended pool, isn't it, in the bottom of water conservation 3-A? Isn't that the deepest? A At times it is. It depends on the regulation schedule. The water tends to be deep. Q Yes. It is the deeper portion of the Everglades as a whole right now, isn't it? A In respect to water level? Q In respect to water level for any extend area in the Everglades. A I can't comment on that. Q Okay.
Honor.
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cross of other counsel and the Court's questions, in the spirit of moving this along, no further cross from the settling parties.
redirect at this point.
(WITNESS EXCUSED)
My partner, Mr. Sams, would like to call our second witness.
box, I would just state to the Court that I haven't previously entered a formal appearance, but I have been in the past admitted to practice before this Court.
GARY NEIL BIGHAM, SWORN AS A WITNESS, WAS EXAMINED AND TESTIFIED AS FOLLOWS:
full name and spell your last name, please.
37 Cross-Maceina-Searchinger
B-i-g-h-a-m.
DIRECT EXAMINATION BY MR. SAMS: Q Mr. Bigham, by whom are you employed and in what capacity? A I am employed by PTI Environmental Services, and I am a principal with that firm. Q And where is that firm located? A In Bellview, Washington. Q And what is the business of PTI Environmental Services and the scope of its compliment of employees? A PTI is a consulting firm. We specialize in environmental sciences. We have a total of about 135 people in the firm and 5 offices across the country. Q Briefly outline your higher educational background, please? A I have a Bachelor's Degree in geology from Oregon State University which I received in 1968; a Master's Degree from Georgia Tech which I received in 1972. Q And in what areas of concentration did you work in in your Master's Degree studies? A My degree was in geophysical sciences there. It was primarily in geochemistry and hydrology. Q Did that include --
38 Direct-Bigham-Sams
A Water quality. Q Did that experience include water quality? A Yes, it did. Q Could you summarize briefly your employment experiences insofar as pertinent. Briefly outline its relevance to your testimony today. A Yes. After receiving my Master's Degree, I went to work for the U.S. Army Corp of Engineers at their Water Ways Experiment Station in Bicksburg, Mississippi. There I helped develop and get started a major research project for the Corp on evaluating the effects of dredging and dredge material disposal in rivers and oceans and estuaries.
District of the Corp where I my primary job there was evaluation of affects of major harbor expansion on water quality levels in Los Angeles harbor.
and over the course of several years was involved in evaluating the affects of disposal of many types of materials into the ocean and into fresh waters, looking at really the fate and water quality and biological affects of those activities.
Environmental Services, and continuing the same types of studies, a little more emphasize this time in looking at
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doing risk assessment to human health and ecological systems. Q Mr. Bigham, what is your area of expertise as you would describe it? A My area of expertise is evaluation of transport fate and affects of contaminants in aquatic environments. Q Have you conducted studies of the transport fate and affects of mercury in aquatic environments? A Yes, I have. Beginning in 1990, or since 1990, I should say, I have been project manager of one of the largest investigations of a behavior and affects of mercury in aquatic systems, specifically in Onondaga Lake In New York.
analysis of total mercury and various mercury species; how it behaved in the lake; perform a mass balance on the system.
mercury behaves, including how it bioaccumlates up through the food level of the particular lake. Q In addition to your work in New York, are you involved with the interpretation of mercury cycling and bioaccumulation in other areas? A Yes, I am. I am currently engaged to evaluate behavior of mercury at other sites in New Jersey, Alabama, Georgia. Also at the Georiga site we are performing ecological risk
Direct-Bigham-Sams
assessment. Q How long have scientists in the U.S. been analyzing mercury cycling and bioaccumulation in the manner that you have done, say, for Onondaga Lake in New York? A Well, actually, not very long. It is a fairly new endeavor, primarily because only until about the mid to late '80's have we had the analytical tools to even be able to analyze for mercury and various mercury species at the very low concentrations that occur in natural waters.
million, or sometimes lower in parts per billion, but the level of the concentration of concern for mercury and methyl mercury is in the parts per trillion range. Q Have you authored or co-authored any peer review publications in the area? A Yes, I have. I am a principal author or first author of one publication and co-authored 3 others regarding mercury cycling and bioaccumulation. Q At this point, Your Honor, I would offer Mr. Bigham as an expert in the transport, fate and affects of mercury in the environment.
objection to Mr. Bigham's qualifications. However, we do object just generally to the relevancy of this whole line of testimony concerning mercury, and it doesn't appear to
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relate to any of the motions that are pending before Your Honor.
under advisement, and we will proceed with the testimony.
BY MR. SAMS: Q Mr. Bigham, is there a mercury bioaccumlation problem in the Everglades? A Yes, there certainly is. There is currently a fish consumption advisory over I think approximately two million acres of the Everglades basically from coast to coast. There is also evidence that higher level organisms are being impacted by mercury bioaccumulation. One, of course, I think high profile example was the Florida panther where mercury may very well have been a contributing factor in a death of a couple of animals.
many of the wading bird species in the Everglades are definitely being exposed and potentially affected by high levels of mercury. Q When you speak of a fish advisory, what are you speaking of, sir? A That is that the State Health Department has issued an advisory to the public that they should limit their consumption of fish caught in the Everglades.
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Q Are there agencies studies underway of the problem that you have described. A Well, yes, there are. Fairly recently there is one of the larger mercury investigations I think in this country is underway funded by EPA. I believe certainly I think funds are also from the State of Florida and also from the South Florida Water Management District. Q Have you conducted analysis of the behavior of mercury and its affects in the Everglades for our clients? A Yes, I have. Q What was the purpose of your analysis? A The purpose of my analysis was to see if there was a relationship at all between phosphorus concentrations in the Everglades and concentrations of mercury in fish tissue. Q Did you find such a relationship? A Yes, we did. We found basically an inverse relationship. That is, that as concentrations of phosphorus decrease in the water, we tend to find elevated concentrations of mercury in fish tissues; specifically some of the small, what we call forage fish tend to be fed on by other organisms. Q What is the environmental significance of the relationship between mercury in water and mercury in fish? A Mercury is somewhat unusual as a contamenant in natural systems, in that it bioaccumlates, and specifically it is
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the methyl form of the mercury. Methyl mercury that bioaccumlates.
on to plankton, periphtyon, which is then consumed by these small fish that we have a fair amount of data for now.
in each step of the way, the concentration of mercury in the tissues of those organisms increases, and then toward the end of the food web, organisms such as the wading birds then get exposed to quite high concentrations of mercury via their diet. Q What affects do elevated concentrations of mercury in, say, the tissue of wading birds have? A The affects on wading birds have been shown in lab studies, as well as recent evidence from the Everglades, to have affects on both the behavior and reproductive success of wading birds. Q I assume those are adverse affects, is that correct? A Yes, sir, they are. Q Have you produced a report on such affects in the Everglades that could arise from proposed reductions in phosphorus concentrations? A Yes, I have. Q I believe that report is the one that we have pre-identified as number 83.
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A That's correct. Q If I could, Mr. Bigham, I would like to first ask you to turn to pages 29 and 30 of your report. Can you demonstrate to the Court or describe for the Court using those pages the inverse relationship that you have identified in the Everglades? A Yes, I can. If you first turn to page 30, which is figure 14, figure 14 shows the locations of the data we have available, and some of the data we have available to us and these are data, by the way, that were collected by EPA in their continuing sampling program.
starts at about the S-6 structure and proceeds eastward into the Loxahatchee.
structure and proceeds southward in WCA-2A basically along that same gradient that Dr. Maceina was talking about. Q If I could interrupt you for just a second, Mr. Bigham. Is the transect that you just described south of the S-10 structures in the same location that Dr. Maceina just referred to in his testimony concerning the so-called moving phosphorus front? A Yes, it is. Q Go ahead, please. A Now, if we turn back to page 29, it says figure 13-B,
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these show the phosphorus in water data and mercury in -- and this is a small fish I was talking about -- the mosquito fish on those two transacts, and the panel on top of the page is that first transect I described.
horizontal axis is distance from the S-6 structure and then going eastward into the Loxahatchee. The solid line represents the total phosphorus concentration, and you can see as right in the vicinity of the canal, or that I guess it is the Tetra Tech model cell number 1, you can see that there is relatively high phosphorus concentrations on this particular sampling, around 50 parts per billion or micrograms per liter, and that as we proceed eastward, that it drops pretty quickly down to values in the vicinity of ten parts per billion.
concentrations in mosquito fish, and bear in mind that mosquito fish have a relatively small range in the Everglades. They never go very far. Their range is on the order of maybe a hundred meters or so. So, they are typically exposed to whatever is going on right in that immediate location.
difference here; that the concentrations or where we have relatively high phosphorus, mosquito fish mercury starts out
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very low. As the phosphorus concentrations decrease, the concentration of mosquito fish go up.
relationship, and that is as we start with looking at phosphorus concentrations at the S-10 structure. Of course, it is high, a lot higher than before it is up around 90 parts per billion and drops quickly and ultimately gets down to that same, around ten parts per billion level. Of course, once it is down there, we see that concentrations in mosquito fish again are going up. This time the direct maximum value is up to around 250 parts per billion in fish tissue. So that is the basically the inverse relationship or one manifestation of the inverse relationship. Q Mr. Bigham, I believe you have already stated it, but just for clarification, are these based on EPA data? A Yes, they are. Q Is the mosquito fish or <TKPWAPL> abuse yeah, the fish that EPA has chosen to handle In its work? A Yes, it is. EPA is using the mosquito fish basically as an indicator species of how in general mercury is being bioaccumulated by these smaller fish species.
the variance, are you in a position to assign any cause for
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this change; the differences that taked place?
we think is a very plausible reason for this; why we see this affect.
answer to the Court's inquiry.
reasoning, or is it based on some connection?
sir?
Honor.
there before. It is there after. It must be the cause of.
changes that are taking place, and so the reason you assign a cause to them is because they took place.
reason behind this relationship. First of all, understand that the source of mercury is primarily from precipitation. In fact, it is typically on the order of about 30 parts per trillion rainfall.
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natural over the last several decades concentration of mercury in precipitation has roughly doubled. So, we have over the Everglades then pretty much everywhere a loading of mercury to the system.
the food chain is it gets absorbed into plankton. In fact, it is just recently that there is, just a couple of papers that have described that mechanism as to how methyl mercury gets up getting concentrated in the psydoplasm or in the interior of plankton or periphyton cells, but it is fairly clear that's happened.
There is a big concentration that takes place there. It gets multiplied by about a thousand times the concentration that was in the water, and now the concentration in the plankton.
small fish eat that, and it gets, as I described before, it gets bioaccumulated, but the relationship with phosphorus is this: That if you had two bodies of water that are basically the same mercury concentration, and in one we have more plankton and the other we have less plankton, that available mass of mercury is going to absorb on to the surface of the particles of plankton, right, and the more particles we have, the lower the concentration will be on
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the particles.
food, it turns out that then that the food web where we have higher nutrient concentrations ends up showing lower levels of bioaccumulation and, conversely, if we have that same mass of mercury, fewer particles available, that mass is going to absorb at a higher concentration on to those particles, so that now that food web in the lower phosphorus or lower nutrient condition tends to bioaccumulate more strongly.
further, also been observed in other systems. It is not unique to the Everglades. This has been noted in some studies in Minnesota. It has been noted in other lakes in Florida. It has also been observed in Sweden.
mean that phosphorus is good?
entire analysis, Your Honor, is that in the course of setting phosphorus standards, I think one needs to be very much aware that you may very well be setting a level of exposure to mercury that we believe this -- I certainly believe that this is a very important relationship that merits much more work.
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but it is a serious affect that needs to be looked at more completely.
careful about about how much we decrease the phosphorus content?
much, much further so that we have a much better idea of what the consequences of a particular phosphorus level would be in terms of mercury bioaccumulation, which we know is already at problem levels.
BY MR. SAMS: Q If I may return to the descriptions of the work that is contained in your report. Why did you choose wading birds as you have described it to the Court as the focus of your study? A For a couple of reasons. One was that wading birds are at the top of the food web, basically. So this process of bioaccumulation and biomagnification, the maximum impact is typically seen at the very top of the food web.
there is recent evidence that indicates right from the Everglades work that's being done for the state has shown that it is very clear that the wading birds are exposed to elevated mercury concentrations.
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especially was just in the process of, when we started our analysis last year, of developing for the first time water quality criteria for the protection of wildlife.
usually for the protection of human health or the protection of aquatic organisms; that is, the fish in the water, but never for protection of wildlife; in this case, fish eating birds and mamals.
in fact, those regulations were finalized earlier this year, and the value of mercury that they came up with was 1.3 parts per trillion as the water quality standard to be productive of wildlife.
Your Honor. Of course, their analysis was largely based on birds as a consumer. So we felt that that was a reasonable indicator to choose, and also that it was prudent to proceed with this, to look at these risks because concentrations of mercury in the Everglades typically exceed 1.3 parts per trillion. We often find levels higher than that, so it looked like a good indicator. BY MR. SAMS: Q What did your report conclude as a general proposition?
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A Our report concluded, as I stated a bit ago, is that we think that, you know, based on our screening level risk assessment, it was quite clear that the potential for harm in lowering the phosphorus concentrations in the Everglades further was real, and that definitely warranted further evaluation to have a better idea of exactly what that trade off looked like. Q Did you identify a phosphorus concentration in water at which you anticipated bioaccumulation would be of concern; mercury bioaccumulation? A Well, what we found was that there was the data kind of falls out into two regions. In the general area of 40 to 50 parts per billion phosphorus. Above that level we never see concentrations of mercury in the mosquito fish over let's say roughly 300 parts per billion.
parts per billion phosphorus, you can get almost any value. They are not all high. Some are low, but the important thing is there doesn't seem to be anything at those low phosphorus levels that is limiting the degree of bioaccumulation. Q Could you describe briefly for the Court how you conducted this study to arrive at this conclusion? A Yes. The way we did the analysis, which is pretty much a standard approach for ecological risk assessment is --
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well, first of all, we started with the phosphorus concentrations from the Tetra Tech phosphorus model that gave us the distribution of phosphorus concentrations around the Everglades; in fact, for each of the cells that are still up on the exhibit there.
water, mercury and mosquito fish so that we could apply a regression equation to that so that we could predict under any or for any given phosphorus concentration what would the concentration be in a small mosquito fish like fish.
assumption that the EPA made in the Great Lakes analysis, which I think is reasonable, that when a larger fish, if it feeds on these smaller fish, it ends up with roughly 5 times the mercury concentration.
and that's the dosage that it is getting. We have literature values that tell us typically how much this fish they eat. We also know how much the birds typically weigh so that we can get, make an estimate of the actual exposure or dosage of mercury that would go into a typical wading bird.
that with what is called a toxicity reference value that was developed by EPA, again as part of this Great Lakes
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analysis, and that toxicity reference value or TRB is basically it is considered to be the exposure or dosage above which adverse affects would be expected.
that we use for coming to our conclusion in this risk assessment as to whether we would expect adverse affects or not. Q Have you attempted to verify whether all of the available data from the Everglades are consistent with your finding? A Yes, we have. Each time we get another set of data from EPA as a continuing monitoring program, we have replotted and compared the data sets, and it has been remarkably consistent.
attention to what we have premarked as exhibit number 84. Your Honor, we have a blow up of that, if I may.
into that?
and large?
atmosphere is -- the natural components really would be from things like volcanic emissions. Some of it actually is, or
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much of it is actually coming from the ocean. It actually evaporates or it is called evade into the atmosphere.
As I mentioned, the concentration of mercury typically you see in the rainfall which comes out of the atmosphere in rain, that's how it ends up in the Everglades. About half of that you might consider natural.
processes. Most of it is from burning of coal, although not all of it is even from this country. A lot of it is still in the atmosphere from like from Eastern Europe.
water from natural rainfall?
that yesterday. They actually get about, as I recall him saying, around 30 parts per billion phosphorus in rainfall. There is also a phosphorus component in rainfall, definitely.
easel where I have placed an enlarged copy of exhibit number 84, and if you could show the Court on that graphic, which is entitled "The Inverse Relationship Between Mercury Concentrations in Fishes And Total phosphorus in Waters in
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the Everglades," what it means. BY MR. SAMS: Q First, let me ask you, did you prepare this exhibit? A Yes, I did. It was prepared under my direction at PTI. Q This exhibit shows basically all of the data available to us from the EPA to date. It includes some of the marsh transect data that we looked at earlier, and includes some fairly recent data from the canals collected by EPA.
when you plot it just in terms of total phosphorus versus mercury and Gambusia.
As I said, there seems to be a major difference in the way mercury is bioaccumulated. When we have a system with phosphorus concentrations less than roughly 50 parts per billion, you can see we have a lot of low values, and the point here is that there doesn't seem to be any limitation, whereas above 50, as I pointed out in our earlier look at the transect in the report, we tend to not get any values much above 300 parts per billion.
the affects of these higher concentrations on upper parts of the food level. Q Mr. Bigham, please remain in the area where you are standing. Have you attempted to project mercury
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bloaccumulation in Everglades wading birds if phosphorus concentrations were required to be 50 parts per billion or less? This question I ask specifically with reference to a concentration at the outflows from the storm water treatment areas. A Yes. We did do some projections. In fact, we focused right on these model cells, 3, 4, 5 and 6, which is the area where we expect the biggest decrease in phosphorus concentrations.
heavily utilized by wading birds for feeding activity, so it is certainly important and relevant. Q What outflow concentrations of phosphorus from the STA's did you examine in this analysis? A We looked at 4 cases. One was the long term averaging or background concentrations. We also looked at STA outflows of 50 parts per billion, 25 and 10 parts per billion, just for a range of comparisons; what that would mean in terms of bioaccumulation or exposure to Great Blue Heron, using that example. Q In general, what did you find in conducting that analysis? I would state, for the record, that I am now having you speak with respect to exhibit number 85 as pre-marked. A Well, what we found, of course, is our ecological risk
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assessment that I described earlier pointed out, is as we decreased phosphorus concentrations, we would expect an increase in the exposure to wading birds.
put that in terms of what is called a hazard index, also known as a hazard quotient. It is a commonly used way of expressing the results of ecological risk, and what this means is if we look at the value of a hazard index of one, that means we are right at that level that's considered to be the acceptable dose, or that TRB that I mentioned before as it has been estimated by EPA.
is currently right about at that level. Then as we decrease phosphorus further, we end up up basically trippling the hazard index, and then, of course, if we go down to ten parts per billion phosphorus case, it is about a 7-fold increase then in this hazard index.
line is 25 parts?
progressively or keep lowering the phosphorus
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concentrations, this hazard index or risk to the Great Blue Heron would increase. BY MR. SAMS: Q Is the risk that you have identified in that exhibit average or based on a mean? A Well, yes. Actually, of course, there is a lot of assumptions in here, and we tried to be extremely careful not to over estimate what the risk might be.
concentration. If I can go back to the earlier exhibit. Basically, the equation or the fitted curve that we used to predict mercury bioaccumulation here was basically more of an average value. We did not use these stream values in coming up with these projections.
think another thing to keep in mind are that it is kind of a reality check that I think is important to keep in mind is that the current case is giving us indications also that if we look at the long term average, that we are about at or a bit above, as in the case of cell 6; what would be the level above which adverse affects would be expected. And since we are starting to see adverse affects, this seems that we are in the right ballpark.
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related to behavorial and reproductive affects. Mercury tends to affect wildlife. For example, they may not exhibit appropriate courtship behavior. They may abandon nests at the wrong time. It also seems to decrease their appetite, so their general fitness reproductive ability is greatly deminished. BY MR. SAMS: Q While you are still up, Mr. Bigham, could you describe briefly for the Court why the cell 6, the last 3 bars, yellow, green and red, appear to be at an even height? A Yes. Another thing we did again to make sure we weren't over-predicting or overly crying wolf, so to speak, is that in the data set we have available, about the lowest phosphorus concentration we have is about 80 parts per billion.
hazard index, any time there was that the Tetra Tech model projected a phosphorus value lower than 8 parts per billion, I just used the value of 8 because less than that is beyond the range of our data and legitimate ability to extrapolate.
higher, but I just chopped them off. Q Mr. Bigham, have any of the birds that you have looked at been designated endangered species, to your knowledge?
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A One of the species that we evaluated in our report Is the Wood Stork which is listed as a threatened and endangered species, yes. Q I believe you can take your seat now. A Can I? Q Yes. Mr. Bigham, did you hear Dr. Goforth testify a couple of days ago that there is enough concern about mercury in the Everglades to essentially warrant the District to conduct a special study in parallel with its studies of the numeric phosphorus limits? A Yes, I did. Q Do you agree with his statement? A I very definitely agree. Q Let me show you a demonstrative exhibit that we have prepared. It is similar to one that Mr. Lehtenin used and, we are not going to introduce this as an exhibit. I am attempting to show the settlement agreement numeric agreements as they are established in that document.
agreement that is part of the discussion before the Court requires these interim and long term phosphorus concentrations for the Loxahatchee Refuge and the Everglades National Park? A Yes. Q Does your study and the continuing data supplied by EPA
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give you any cause for concern about these levels? A Well, these levels are all within the ranges which we would predict adverse affects to wading birds.
the admission of exhibits 83, 84 and 85 as pre-numbered.
reserve objection on that, since this is a rather lengthy report. We haven't had a chance to look at it at this point.
advisement. We will continue.
would just like to point out that the report is dated June, 1995, and has been available in its prior forms, as well as that one to the agencies.
that point in time.
receive them in evidence, and if counsel has any serious objection to some part of it, I will hear him on it later on.
of the relevance concern raised by Mr. Nettleton before,
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there is a lot in evidence that we could submit to talk about on mercury in this proceeding. And if mercury is really an issue in this proceeding, if it is considered a relevant issue, then there is a whole lot of other evidence.
to phosphorus and the balances that appearantly do have some relevancy to the question of phosphorus content.
considered by all of us, and particularly by the Court in doing whatever it is going to do or whatever I am going to do. All right. Do you have something more?
Bigham for cross-examination.
an hour and a half. Let's take about 10 minutes. (RECESS TAKEN)
Nettleton.
CROSS-EXAMINATION Q Mr. Bigham, I would just like to clarify a couple of items. I believe in response to questions from the Court you indicated, did you not, that atmosphere deposition, that is rainfall and particles, dry particles settling from the atmosphere are the dominant contributor of mercury to the
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surface waters in the northern hemisphere? A Well, not all surface waters in the northern hemisphere. My reference was really to the Everglades. Q So with regard to the Everglades then? A Yes, that's correct. Q And you also indicated, I believe -- and these are probably my words, not yours, but the research in the mercury cycling area in the ecosystem is pretty much in its infancy, is that right? A Yes. It has expanded very, very rapidly in the last several years since the late '80's. Q But the technology and quality control and methodologies have really just been developed within the last decade, is that right? A Correct. Q And you mentioned that the form of -- well, let's talk about mercury cycling. In mercury cycling we are really primarily concerned with, if I am correct, the 3 forms of mercury, the mecuric, ion and on elemental mercury and methyl mercury, is that right, in general? A Primarily, that's correct. Q Okay. And methyl mercury is the form which is a human health concern and an ecological concern, is that right? A Yes, it is. Q All right. And am I correct when we refer to mercury
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cycling, you are referring to the processes that lead to either methylation or demethylation of other forms of mercury into methyl mercury or back the other way? A Yes. Mercury cycling really in general refers to the behavior of these various mercury species, because again mercury is somewhat unusual because sometimes when we speak of lead or cadmium, or something like that, we are concerned about the total concentration, but the concern is not just total mercury.
which is the more toxic species, that's right. Q And would you agree that given the current scientific knowledge in this area, that it is unclear whether the dynamics of methylation are primarily under biological or geochemical control? A Well, I think the evidence in the literature is pretty clear that it is primarily biological and mediated by sulphate reducing bacteria.
particular type of bacteria that are ubiquitous that occur virtually anywhere and seem to be responsible. It is a product of their metabolism they seem to, incidently, end up converting ionic mercury to a methyl form. Q Would you agree that the sulfate reducing bacteria
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activity is not as important in fresh water systems as salt water systems? A No, I would not. Q The mercury cycle as we have discussed in methylation and demethylation of mercury, does that occur naturally in the ecosystem? A Yes, it does. Q And would you agree that currently there are little if any, and I will ask you whether there are any existing scientific studies in peer review journals relating to the mercury cycle in subtropical wetlands such as the Everglades? A Yes. I am aware of a couple of articles that deal with the Everglades. I think work by Jerry Stober of EPA has been published. There may be a couple of others that I am not aware of yet. Q Are you aware of any such published articles that deal with the phosphorus hypothesis that you have discussed here today? A Not for the Everglades, no. There are other papers that have posed a similar relationship between phosphorous or a degree of utrification and mercury bioaccumulation similar to what we have seen in the Everglades. Q And what are the geographic areas of those studies? A Many of then are from Sweden where they have looked
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fairly extensively where they have a significant problem with elevated mercury and bioaccumulations in Swedish lakes.
location specific. It was talking more from a theoretical basis. Q Okay. Well, would you agree that a system in Sweden would not be as useful a tool as far as a modeling tool for predicting how mercury may cycle in an ecosystem such as the Everglades? A Well, it is very hard to say. First, you have to kind of work out the science of what has really gone on in the system before you can model it. If the fundamental processes are the same, it would. If they are not, it is quite clear that we have a ways to go in understanding the the or in working out the science of mercury bioaccumula | ||||
