108
1 DIVISION OF ADMINISTRATIVE HEARINGS
DEPARTMENT OF ADMINISTRATION, STATE OF FLORIDA
2
SUGAR CANE GROWERS COOPERATIVE )
3 OF FLORIDA; ROTH FARMS, INC.; and )
WEDGWORTH FARMS, INC., )
4 )
Petitioners, )
5 vs. )DOAH Case No. 92-3038
SOUTH FLORIDA WATER MANAGEMENT )
6 DISTRICT, an agency of the State )
of Florida; et al., )
7 Respondents. )
- - - - - - - - - - - - - - - - - x
8 FLORIDA SUGAR CANE LEAGUE, INC., )
UNITED STATES SUGAR CORPORATION; )
9 and NEW HOPE SOUTH, INC., )
Petitioners, )
10 vs. )DOAH Case No. 92-3039
SOUTH FLORIDA WATER MANAGEMENT )
11 DISTRICT, an agency of the State )
of Florida; et al., )
12 Respondents. )
- - - - - - - - - - - - - - - - - x
13 FLORIDA FRUIT AND VEGETABLE )
ASSOCIATION; LEWIS POPE FARMS; )
14 W.E. SCHLECHTER & SONS, INC., )
and HUNDLEY FARMS, INC., )
15 Petitioners, )
vs. )DOAH Case No. 92-3040
16 SOUTH FLORIDA WATER MANAGEMENT )
DISTRICT, an agency of the State )
17 of Florida; et al., )
Respondents. )
18 - - - - - - - - - - - - - - - - - x
100 Southeast 2nd Street
19 Miami, Florida
March 16, 1993
20 9:15 a.m. - 6:00 p.m.
21
DEPOSITION OF ALLEN S. LEFOHN
22 VOLUME II - P.M. SESSION
23
Taken before RICHARD BURSKY, Registered
24 Professional Reporter and Notary Public in and for
the State of Florida at Large, pursuant to Notice of
25 Taking Deposition filed in the above cause.
109
1 AFTERNOON SESSION
2 1:20 p.m.
3 BY MR. NETTLETON:
4 Q. Dr. Lefohn, would the addition of a
5 limiting nutrient to an oligotrophic water body cause
6 eutrophication in your opinion?
7 A. Well, my expertise is not eutrophication
8 in terms of the limiting nutrients and such. So I
9 feel like I am answering questions that are not
10 associated with my educational background.
11 Q. What in your opinion is the significance
12 of soil acid versus rainfall acid with regard to
13 ecological effects?
14 A. Could you rephrase that question? I think
15 I know what your point is but I would like to hear
16 that again in a different way.
17 Q. How do you attribute the effects of acid
18 through soil cycling or soil processes versus acid
19 from rainfall?
20 A. In some cases the high concentrations of
21 aluminum that were observed in the surface waters
22 occurred at the same time the pH depressions occurred
23 during runoff and so aluminum was acting like a
24 tracer that it was coming from the soil and not from
25 deposition.
110
1 And the acids in most cases, almost all
2 cases the soils that were we were looking at were in
3 forests and pHs were fairly low and aluminum was
4 observed in high concentrations at the same time.
5 And overland flow was playing a minor role in places
6 such as Hubbard Brook and other places that were
7 documented.
8 Q. Is there a difference though in the
9 ecological effect on the biota or the microbial
10 communities or what have you if the acid is from
11 deposition or from soil processes?
12 A. In some case is yes, in some cases no.
13 Q. Can you describe the different cases?
14 A. Yes. In some cases you have weak acids
15 associated with the organic acids coming down and
16 they have a different effect than strong acids such
17 as sulfuric acid. But sometimes in fact the strong
18 acids were coming off as Dr. Krug had found due to
19 natural processes.
20 A. They were not just, in other words,
21 sulfuric acid coming off into a water body was just
22 not attributable to sulfuric acid falling out of the
23 sky.
24 THE WITNESS: Did you get that?
25 Q. I don't know if I got it.
111
1 A. H2SO4 is the sulfuric acid.
2 Q. Right.
3 A. The paradigm was that if it is sulfuric
4 acid it is impacting your lakes, the sulfate that is
5 in your lakes and the acid that is in your lakes
6 comes from the atmosphere, comes from man-made SO2
7 reacting to form sulfuric acid. However, what Dr.
8 Krug found, it is possible to actually get strong
9 acids through natural processes going off into the
10 water body. It was just not weak inorganic acids
11 that were running off.
12 Q. Is there a difference in effect depending
13 on the source of the acid? Again, maybe I am
14 misunderstanding your answer.
15 A. My answer was that sulfuric acid will
16 probably have a different effect than the weak
17 organic acid just on its ability to titrate. So
18 effectively the sulfuric acid though is just not
19 attributable to man-made activities. In other words,
20 from man you get sulfuric acid or nitric acid. From
21 the natural processes you also get sulfuric acid plus
22 weak organic acids. Therefore there is a difference
23 potentially between the two acids but to simply say
24 one acid is coming from man and other acid is coming
25 from natural is incorrect.
112
1 Q. I understand that. I am not sure whether
2 you still answered my question. Is there a
3 difference in effect to the biota depending on the
4 source?
5 A. I am not sure I understand the question.
6 Q. Is there any difference in the effect on
7 the biota from the source of the sulfuric acid or is
8 sulfuric acid sulfuric acid?
9 A. Sulfuric acid is sulfuric acid, that's the
10 point I was trying to make.
11 Q. From what we have discussed this morning
12 and your educational background in chemistry and all,
13 I am curious as to what it is in your background and
14 your education and your experience which you consider
15 qualifies you to be an expert on the effects of the
16 various chemical compositions on, essentially the
17 ecological effects --
18 MR. BLANK: I object to the form of the
19 question.
20 Q. Can you tell me what you consider your
21 qualifications are to provide opinion testimony in
22 that regard?
23 A. Yes. I am highly experienced in the
24 characterization of deposition data, wet deposition
25 data and some of the bulk data that I have looked at,
113
1 the linkages to biological effects is coming from the
2 fact that I ran the ecology branch in Corvallis,
3 Oregon and during that time my responsibility was
4 working with the biologists in dealing with the
5 effects component and relating physical chemistry to
6 that.
7 Since then I have worked very closely with
8 scientists from all over the world on the ecological
9 side and the vegetation effect side concerning what
10 exposure elicits an adverse effect, and consequently
11 my responsibility is not just the characterization
12 but actually taking it all the way to the exposure
13 response equation with the help of those individuals
14 who have actually done the fumigation experiments in
15 the laboratory.
16 And I have actually designed the exposure
17 regimes hand in hand with the researchers who
18 implemented the actual exposure of the crops.
19 Q. Am I correct then that your qualifications
20 with regard to ecological effects derive from what
21 you have just described as your experiences with
22 working with the biologists and so forth as opposed
23 to your educational background per se in chemistry?
24 A. The chemistry part of the characterization
25 and such comes from my training in chemistry, physics
114
1 and math. The biological experience comes from
2 working with the researchers themselves and
3 essentially designing experiments for them, as well
4 as my appreciation of running or participating in the
5 creating of national programs in Washington, D.C.
6 Q. What research if any has the Animal
7 Ecology Lab in Oregon done with regard to nutrient
8 responses?
9 A. Let me give you a quick history.
10 The animal ecology branch no longer exists
11 and the laboratory no longer exists. EPA decided to
12 abolish its theme laboratories about the time I left
13 EPA.
14 However, the Corvallis Environmental
15 Research Laboratory was heavily involved in
16 eutrophication, the facility itself was a body and
17 within that there were components of which one was
18 the national ecological research laboratory which I
19 ran and the ecology lab. The lab itself to date was
20 very involved in eutrophication activities.
21 Q. What was your role in those eutrophication
22 activities?
23 A. While I was in Corvallis?
24 Q. Yes.
25 A. None.
115
1 Q. What about before or after you were there?
2 A. Before I was in Corvallis my role, as I
3 indicated earlier, was working in Washington, D.C. to
4 put together the program that involved working with
5 the laboratory people in Corvallis while I was in
6 Washington, D.C. as well as working with the
7 laboratory people in Las Vegas who were worried about
8 the helicopters and aircraft and platform material.
9 Q. That is what you described earlier
10 concerning the EPA survey?
11 A. Yes, that's correct.
12 Q. Have you done any other work other than
13 that with regard to eutrophication research?
14 A. Since then, no.
15 Q. What about before then, had you done
16 anything regarding eutrophication research?
17 A. I don't believe so. It was when I was in
18 Washington, D.C.
19 Q. When were you first contacted about
20 providing services for this particular litigation?
21 A. I believe September or October of 1992.
22 Q. Who contacted you?
23 A. Counsel.
24 Q. Who specifically?
25 A. I think it was, Bill Earl was my first
116
1 contact.
2 Q. Are you under contract with Mr. Earl's
3 firm to provide services?
4 A. Yes.
5 Q. Is that a written contract?
6 A. Yes.
7 Q. How are you being compensated?
8 A. On an hourly basis.
9 Q. What is your hourly rate?
10 MR. BLANK: Go ahead, you can answer.
11 THE WITNESS: My hourly rate?
12 MR. BLANK: Yes.
13 A. My hourly rate is $125 an hour.
14 Q. You charge the same thing for testimony as
15 your research activities?
16 A. No.
17 Q. What is the difference?
18 A. Double during the time I am here.
19 Q. So you are charging 250 an hour for
20 testimony?
21 A. When I am in a deposition.
22 MR. NETTLETON: Off the record.
23 (Discussion off the record)
24 MR. NETTLETON: Back on the record.
25 BY MR. NETTLETON:
117
1 Q. Had you ever worked for Mr. Earl's firm
2 prior to this engagement?
3 A. No.
4 Q. Are you being paid by the firm of Peeples,
5 Earl & Blank or by their clients, the Florida Sugar
6 Cane League?
7 A. The checks are from counsel.
8 Q. What have you been asked to do in this
9 case?
10 A. I have been asked to -- there are two
11 phases. One phase is to look at what has been done
12 to date and draw some conclusions concerning what I
13 have evaluated and the second phase has to do with
14 rendering an opinion concerning what the deposition
15 loading is in Southern Florida, in South Florida.
16 Q. When you say look at what has been done,
17 what are you referring to?
18 A. Evaluate the material that has been
19 provided to me.
20 Q. Have you been asked to do anything else
21 other than the two things you have just mentioned?
22 A. Not that I can recall.
23 Q. What materials have been provided to you?
24 A. I have seen the SWIM Plan -- there was a
25 list that was provided to you recently, so I am doing
118
1 that from memory right now.
2 Q. All right.
3 A. So pardon me if I do not remember each of
4 the numerous items.
5 There was the SWIM Plan, there was the
6 draft paper by Grimshaw that I gather is under peer
7 review, at least I received it as the paper had gone
8 off to be reviewed. There is a piece by Walker that
9 was done I believe for the Justice Department that
10 was an evaluation of the Everglades National Park
11 data that the District had collected.
12 There was a memo from I believe Grosser
13 dealing with quality assurance, there was an Appendix
14 E that Mr. Grimshaw had written I believe in 1989
15 that appeared to be supporting material to the
16 information that went into the SWIM Plan. There were
17 several tables and such concerning the calculations
18 of how the average concentrations for the twelve
19 sites were calculated and the flow rated mean were
20 calculated.
21 There may be other additional things I
22 have just not remembered at this point that were in
23 the list.
24 There were a couple of publications also.
25 MR. NETTLETON: Mark that, please.
119
1 (A letter dated March 1, 1993 from Mr.
2 Blank, was marked Lefohn Deposition Exhibit 2 for
3 identification)
4 BY MR. NETTLETON:
5 Q. Showing you what has been marked as
6 Exhibit 2, is that the list of documents contained in
7 that letter that you are referring to?
8 A. Yes.
9 Q. Other than those documents set forth on
10 there, have you been provided any additional
11 materials?
12 A. Yes. Recently I received a diskette from
13 counsel that had been sent from the District to
14 counsel that contained some volume information that
15 was associated with some of the samples collected at
16 some of the sites. These were data that we had asked
17 for previously.
18 Q. Is that the information that is referred
19 to in the final paragraph of the letter that the
20 League's counsel was awaiting receipt of?
21 A. Yes, I believe so.
22 Q. When did you receive that?
23 A. Around March 5.
24 Q. When did you receive the other items set
25 forth in the letter?
120
1 A. The item A is a paper I received from
2 Bowersox about six weeks ago.
3 The Grimshaw '89 I probably had received
4 about two months ago.
5 The paper by Grimshaw, Shih and Gatz may
6 have been about a month ago. Grosser was probably
7 about a month. And the NADP/NTN data summary
8 information I have had for a long time and that was
9 just in my records, get that from the disk.
10 The disk rain information may be in
11 February, early February; the Surface Water
12 Improvement -- the SWIM Plan itself probably in
13 November and the Walker piece probably also in
14 November.
15 Q. With regard to the SWIM Plan item, I
16 believe the reference there is to the supporting
17 information document. How many volumes of the SWIM
18 Plan did you receive?
19 A. Three.
20 Q. Other than those items and the information
21 you just recently received on March 5, is there any
22 other information or materials that have been
23 provided to you?
24 A. I have been provided a lot of other -- not
25 a lot of other but other material which I am not
121
1 necessarily dependent upon for drawing conclusions.
2 Q. What other materials were provided?
3 A. Several reports from the USGS concerning
4 rain chemistry, one dated 1965, the other dated 1980
5 or 1981.
6 I have been provided -- are you asking
7 that others have provided to me associated with this
8 case?
9 Q. Right.
10 A. That people from all over the country or
11 people just associated with the case itself?
12 Q. Well, let me break it down. First what
13 were you provided by the Peeples Earl & Blank law
14 firm with regard to this case?
15 A. There were several appendices associated
16 with the report, but I can not remember the exact
17 title of the report, basic summary information of
18 data, not necessarily data but analysis and reports
19 that others had done in the past over the last
20 several years, some of them District reports, some of
21 them government reports from USGS, various reports.
22 I am sorry I can't be more specific at this time.
23 Q. What did the reports deal with?
24 A. Some dealt with water chemistry itself,
25 surface water chemistry. Some of the reports dealt
122
1 with the quality assurance program, components of the
2 quality assurance program.
3 I have received the actual data for the
4 USGS three month comparison study for colocated
5 samplers for the 1992 period.
6 The other appendices and such, it is very
7 difficult for me to remember right now all of the
8 details of all that information. But most of that I
9 did not depend on, those other things that I have not
10 cited here I have not depended on for drawing my
11 conclusions to date.
12 Q. You refer to these as appendices to a
13 report. What report are you referring to?
14 A. A report that was done by, for counsel and
15 they were appendices of xeroxes of reports and such
16 that others provided, others had done.
17 Q. Who prepared the report?
18 A. I believe it was Hydrologic Associates.
19 Q. Do you know when that report was prepared?
20 A. I'm thinking 1991.
21 Q. Can you tell me what that report was
22 about?
23 A. It was a summary of the different types of
24 monitors that the District had used to date, the
25 types of quality assurance protocols that were being
123
1 followed, some of the problems that were associated
2 with the various monitoring approaches, some of the
3 techniques.
4 Q. When you refer to types of monitors, what
5 are you referring to?
6 A. Different types of wetfall collectors or
7 dryfall collectors and different designs.
8 Q. When you refer to the QA/QC what are you
9 referring to?
10 A. Some of the quality assurance/quality
11 control protocols that were being followed in terms
12 of how the samples would be preserved.
13 Q. Do you recall what the report stated about
14 that?
15 A. No. It was general. My recollection is
16 there were no bottom lines concerning strengths,
17 weaknesses of different techniques. It was more or
18 less a documentation of what was going on.
19 Q. Were the reports that were appended to it
20 cited as the authority for whatever they were stating
21 inside the report?
22 A. Not necessarily. To me, it appeared to me
23 that some of the appendices were just what had been
24 done in certain areas. For example, the Walker
25 report was one of the appendices.
124
1 Q. The problems with monitoring, what
2 problems did they identify?
3 A. I think the data collection problems in
4 terms of the efficiency was one issue that may have
5 been raised. The preservation of the samples may
6 have been another.
7 Q. Any others you can recall?
8 A. No. I can not recall any others at this
9 time.
10 Q. Did Hydrologic Associates reach any
11 conclusions in their report?
12 A. I believe they did not. I believe it was
13 mostly a narrative of what was going on.
14 Q. Do you know what time period was covered
15 by the report?
16 A. I believe it was through 1990. And I
17 don't recall, other than I know that the District has
18 samples going back to 1974, but I don't recall how
19 far it went back.
20 Q. Were you asked to provide any comments on
21 the report?
22 A. No.
23 Q. Other than the Hydrologic Associates
24 report and the appendices thereto, were you provided
25 any additional information or documents other than --
125
1 A. From counsel or from other sources?
2 Q. From counsel.
3 A. There was quality assurance information
4 that was provided to me, of which I passed on to an
5 associate of mine.
6 Q. Who is your associate?
7 A. Well, associates meaning a peer which is
8 Dr. Krupa.
9 Q. Why did you pass it to him?
10 A. Because Dr. Krupa was a subcontractor to
11 my company, A.S.L. & Associates, to evaluate the
12 quality assurance and the quality control.
13 Q. Can you spell Krupa?
14 A. K R U P A.
15 Q. The QA/QC that you were provided, was that
16 a specific document or program?
17 A. No, it was whatever documentation we could
18 find which included the Grosser piece, the memo that
19 was provided to us sometime the beginning of the
20 year. I think it was drafted in January 1993 but it
21 was provided to us in February. So it is whatever
22 information that had been sent to us, some of the
23 appendices that I referred to plus Grosser.
24 Q. Did this include any information
25 concerning laboratory analysis QA/QC?
126
1 A. I don't recall. For this specific case my
2 responsibility was to identify the sources and just
3 send them on to Dr. Krupa.
4 Q. What do you mean by identify the sources?
5 A. What I meant, what material was available
6 I passed on.
7 Q. Anything else that was provided to you by
8 counsel?
9 A. At this point I can not think of anything
10 else.
11 Q. What other reports or materials or
12 documents did you receive from third parties with
13 regard to your work in this case?
14 A. I have -- I have received annual reports
15 from the National Acid Deposition Program on a
16 routine basis and that material resides in my office.
17 It is public information, the documents are public
18 information distributed by the government.
19 I had asked and received from Dr. Bowersox
20 a copy of his paper which you have a copy of also.
21 I have received raw data from governmental
22 sources of the NADP sites in Florida, national acid
23 deposition sites in Florida.
24 And I have received a tape from Electric
25 Power Research Institute on some of its wet
127
1 deposition data.
2 Q. What kind of tape?
3 A. I am sorry, it is a magnetic tape of data.
4 Q. What type of information is on that tape?
5 A. Wet deposition data, it is associated with
6 the anions and cations which include orthophosphate.
7 Q. Is that included in the EPRI data base we
8 discussed earlier?
9 A. Yes, that's correct.
10 Q. Any other information you received from
11 third parties?
12 A. I have received recently as late as late
13 last week references to two peer review papers that
14 deal with the determination of wet chemistry in terms
15 of how the calculations are made for volume weight
16 concentration.
17 Q. Do those papers provide any novel ideas
18 that haven't been followed in the past concerning
19 volume weighting?
20 A. What it did was supply me with additional
21 information in the peer review literature for support
22 for some of the conclusions that I drew concerning
23 the, why one uses volume weight concentration.
24 Q. Anything else you received from third
25 parties?
128
1 A. Yes. There is one other thing I did
2 receive from counsel. There is a paper by Hendry and
3 Brezonik and Edgerton and they have, that paper
4 summarizes the deposition data for Florida for the
5 late 1970s.
6 Q. Any additional materials that you have
7 received with regard to this case?
8 A. Nothing additional I can think of at this
9 time.
10 MR. BLANK: Just for clarification
11 purposes, because I don't want there to be any
12 confusion in terms of what he has received, and I
13 don't know that you have covered it in your
14 questions, but I know you have received the
15 District's rainfall data and that was referred to in
16 the first paragraph of the letter and not one of the
17 inserts.
18 A. Yes, I am sorry. Yes, I am sorry, I did
19 receive a diskette of those data.
20 Q. I was referring to things that are not
21 stated in the letter that has been marked as Exhibit
22 2.
23 A. The item F on the list was not the
24 chemistry data. I believe it was associated more --
25 there may have been some chemistry data on there but
129
1 the reason that diskette was sent to us was at the
2 time it was thought that was the volume data but in
3 fact it turned out to be for every day the rainfall
4 amount for just a few sites. I did receive on a
5 separate diskette a copy of the data starting from
6 1974 through I believe 1992 for some of the sites.
7 Q. And that's what is referred to in the
8 opening paragraph of the letter?
9 A. Which sentence are you referring to, this
10 sentence --
11 Q. The District's rainfall data for South
12 Florida.
13 A. Yes.
14 Q. Any other materials you have received from
15 either counsel or third parties relating to your work
16 on this case?
17 A. Not that I can recall at this time.
18 Q. Has any information been conveyed to you
19 orally as opposed to by documents that you have
20 utilized for your work in this case?
21 A. No, I am fairly certain I have depended
22 upon written materials.
23 Q. Other than the materials we have discussed
24 that have been provided to you, have you reviewed any
25 other materials of any nature for purposes of your
130
1 work on this case?
2 A. I have reviewed my own Kriging papers.
3 Q. Which specific ones?
4 A. The White House report, the State of
5 Science Report No. 7 as well as the paper on page 17,
6 Lefohn, Knudsen and McEvoy 1988 as well as the paper
7 on page 17 by Knudsen and Lefohn, The Use of Spatial
8 Statistics to Characterize Regional Ozone Exposures.
9 Q. Why were you reviewing your Kriging papers
10 for purposes of your work on this case?
11 A. For evaluating the Kriging procedures that
12 were followed by the District.
13 Q. Did you reach any conclusions as to the
14 appropriateness of the Kriging procedures being
15 followed by the District?
16 A. Yes.
17 Q. What is your conclusion?
18 A. That the procedures were inappropriate.
19 Q. Were inappropriate?
20 A. Yes.
21 Q. What is that based upon?
22 A. It was based upon several things.
23 One, the data that were used were
24 inappropriate to be used in the Kriging.
25 Number two, it was uncertain that the
131
1 model itself was appropriate.
2 And number three, the way the data
3 themselves were characterized was inappropriate.
4 Q. I will come back to that in a second.
5 Are there any other materials that you
6 have reviewed with regard to your work that you have
7 done on this case?
8 A. I don't recall any.
9 Q. With regard to your opinion that the
10 District's Kriging procedure was inappropriate, you
11 stated first that was based upon the fact that the
12 data was inappropriate, is that correct?
13 A. That's correct.
14 Q. Why do you say the data was inappropriate?
15 A. Because the samples that were measured
16 came from different years. In some cases there were
17 three samples or two samples collected entirely for a
18 particular data point. In other cases they, the data
19 may have been gathered for longer periods of time but
20 not at the same periods of time as other data that
21 were used. For example, data may have been gathered
22 for the period 1976 through 1982 or 1983 and stopped
23 and for another site the data would have been
24 gathered from 1985 through -- into 1989.
25 And that is just an inappropriate way to
132
1 use the data to Krig.
2 Q. Why is that inappropriate?
3 A. Because the appropriate way would have
4 been to Krig -- to calculate the deposition and to
5 Krig the deposition for each year and use all the
6 data that were available by each year, and then get
7 values for each year into the area which they were
8 interested in which was the WCAs and to come up with
9 an annual value and then average that if they were
10 looking for an average value between the periods of
11 1974 into 1989.
12 Instead, what appeared to be done, and I
13 say appeared because the documentation was not very
14 strong in the SWIM report, was that they
15 calculated -- they collapsed all the data for twelve
16 different monitors, some are, for example, Homestead
17 had only a very few number of samples, it may have
18 been three or four samples. Another site had only
19 nine samples and they treated them in an equivalent
20 way which means they weighted them in evaluating
21 saying two or three samples gave a quick snapshot of
22 what was going on at that site over a nine or ten or
23 twelve year period.
24 And for another site they may have had 199
25 samples over the same time period which perhaps
133
1 better represented what was going on over several
2 years. So they essentially Kriged data, tracing the
3 data at that time at each point as if it were
4 weighted in an equal way and that was incorrect.
5 Q. What is inappropriate about the model
6 itself?
7 A. It was unclear why universal Kriging was
8 used. Ordinary Kriging is a technique that usually
9 is applied and that if there tends to be a trend in
10 the data or something like that, then they go to a
11 different model of Kriging.
12 And we attempted to get from the District,
13 obtain from the District the information that would
14 have allowed us to get a better feel for why
15 universal Kriging was used. And to the best of our
16 knowledge at this time the documentation just is not
17 there. It may be there but we have not received it.
18 We have requested it. Hence --
19 Q. What --
20 A. Go ahead.
21 Q. I am sorry.
22 What is the difference between universal
23 Kriging and normal Kriging?
24 MR. BLANK: Do you mean ordinary Kriging?
25 Q. Ordinary Kriging, excuse me.
134
1 A. As such. A different model is used and
2 the person that I work with on this is Dr. Knudsen.
3 He is a coauthor and he is the Kriger. And Dr.
4 Knudsen and I have discussed the approach that was
5 used by the District and based on his conclusions I
6 am now reflecting that in what I am saying now in the
7 difference between ordinary and universal Kriging.
8 He is an actual modeler that uses the data, does the
9 Kriging physically.
10 Q. So your on conclusion is based upon your
11 discussions with Dr. Knudsen and his opinions
12 concerning the District's Kriging procedures?
13 A. No. You asked me what the difference was
14 between ordinary Kriging and universal Kriging and
15 what I am saying, what I am responding to that
16 question is that Dr. Knudsen would be more qualified
17 to tell you the difference in the models.
18 What Dr. Knudsen has indicated to me is
19 that it is unclear why the District selected
20 universal Kriging over ordinary Kriging but that one
21 point is not the basis of my conclusion concerning
22 inadequacy of the Kriging effort.
23 Q. The third item you mentioned was the way
24 the data itself was characterized was inappropriate.
25 What do you mean by that?
135
1 A. The data, to use simple arithmetic means
2 is just totally inappropriate to determine what the
3 deposition was. In my opinion, the District was
4 attempting to determine what the deposition was in
5 the WCAs. To simply use the arithmetic means is
6 incorrect.
7 Q. What should they have used?
8 A. If they wanted to do what they did, first
9 of all, I have already made the point about, it is
10 unclear whether the data would even support the use
11 of Kriging because of the fact of the different time
12 frames that the data were gathered.
13 If the data were -- if you could use the
14 data, what should have been done is either calculate
15 the deposition at each site, supposing at each of the
16 twelve sites, supposing you had good coverage for
17 each year, and then Kriged that deposition into the
18 WCAs, or what some people have done is use the volume
19 weighted concentrations and the amount of rainfall
20 from data bases that are available and that doesn't
21 necessarily mean the rain gauge values at each -- you
22 could only use the rain gauge values at each monitor
23 but you have airports and such, and you essentially
24 do Kriging of both.
25 You Krig the rainfall amount, rain gauge
136
1 value and you also Krig the volume weight
2 concentration and you multiply the two to get the
3 deposition in the area, in the WCAs.
4 Q. What precisely is the source of your
5 information as to the Kriging procedures that you are
6 assuming were followed by the District?
7 A. The SWIM Plan, the, I want to say
8 supporting document, what I referred to, supporting
9 information document.
10 Q. Other than discussing the universal versus
11 ordinary Kriging with Dr. Knudsen, did you discuss
12 any of the other aspects of your Kriging opinion with
13 him?
14 A. Yes. Dr. Knudsen and I discussed what I
15 discussed right here, which is the inadequacy, the
16 potential inadequacy of the data base because of the
17 not overlapping of the monitoring collection at the
18 same time and the fact that they were Kriging just
19 the concentration instead of the deposition.
20 Q. Were the factors -- let me back up. Did
21 Dr. Knudsen review the SWIM Plan document as well?
22 A. Yes.
23 Q. Were these opinions concerning the
24 inadequacy of the District's Kriging procedure first
25 arrived at by Dr. Knudsen or yourself?
137
1 A. I drew some preliminary conclusions for
2 background purposes and then sent the information to
3 Dr. Knudsen once I obtained it.
4 Q. Describe to me what happened after that.
5 A. He independently went through three
6 volumes of the SWIM Plan, the supporting information
7 document was the piece that he primarily drew his
8 conclusions on. But there was a small part of the
9 appendix which is the third document that had a
10 contradictory statement in it that talked about 13
11 sites used for Kriging and he noted that at the time,
12 whereas the SWIM Plan second volume referred to the
13 12 sites.
14 Q. Where is Dr. Knudsen located?
15 A. Montana Tech in Butte, Montana.
16 Q. Is he being compensated for his review of
17 this material?
18 A. Yes, he is.
19 Q. Who is paying him?
20 A. I am paying him. He is under contract to
21 me. When I say me, A.S.L. & Associates, my
22 corporation.
23 Q. Why did you contract with Dr. Knudsen?
24 A. Dr. Knudsen is a Kriging expert in that he
25 actually does the Kriging, does the mathematics, is
138
1 probably one of the experts, one of the most highly
2 thought of experts in the world and I believe he was
3 also cited in the SWIM Plan itself. Dr. Knudsen and
4 I have worked very closely together since about
5 1984-85 on Kriging air quality information.
6 As a mathematician statistician which he
7 is, I respect his opinion and have used him as an
8 independent resource.
9 Q. Has Dr. Knudsen ever been involved in
10 Kriging with regard to phosphorus concentrations?
11 A. No, to the best of my knowledge, no.
12 Q. Have you ever been involved in anything
13 like that?
14 A. The Kriging of phosphorus, no.
15 Q. Are you relying upon the opinions of Dr.
16 Knudsen to support your own opinions?
17 A. No.
18 Q. Do you consider Dr. Knudsen more qualified
19 in the area of Kriging than yourself?
20 A. He is very qualified in the area of the
21 actual use of the data in the modeling. He is more
22 qualified than I am in terms of the actual Kriging.
23 But I consider myself highly qualified in terms of
24 the interpretation.
25 Q. How do you evaluate whether one Kriging
139
1 method is superior to another?
2 A. In terms of the actual mathematics and the
3 model used, that is -- I personally depend on a
4 mathematician similar to Dr. Knudsen basically to
5 judge whether or not the assumptions built into the
6 Kriging allow for the use of ordinary Kriging versus
7 universal Kriging versus any other.
8 Q. So you are relying on Dr. Knudsen for that
9 particular aspect of your opinion?
10 A. As to whether the model itself was
11 appropriate, that's correct.
12 Q. Is it possible to validate or verify which
13 Kriging method is more appropriate?
14 A. By looking -- there are a lot of ifs on
15 this. If the data base itself were appropriate and
16 could be used, then it would be possible to validate
17 which model would be most appropriate, if the data
18 base itself were appropriate to be used as input.
19 As an alternative we attempted to locate
20 background information from the District to give us
21 some ability to judge that without having to rerun
22 the data and that data was not available, at least
23 not made available to us.
24 Q. Has such a verification ever been done
25 with regard to phosphorus in rainfall to your
140
1 knowledge?
2 MR. BLANK: I object to the form of the
3 question.
4 THE WITNESS: Am I supposed to respond?
5 MR. BLANK: You can go ahead and answer.
6 THE WITNESS: All right, I am sorry.
7 A. The actual Kriging of phosphorus data, of
8 deposition data, I am unaware of other than what was
9 attempted by the District.
10 Q. What was attempted by the District to your
11 knowledge?
12 A. To my knowledge, they were attempting to
13 estimate what the deposition in the WCAs were.
14 Q. And that is what you are criticizing, what
15 your opinion is, their procedures were inappropriate,
16 is that right?
17 A. To get to the estimate of the phosphorus
18 deposition, total phosphorus deposition in the WCAs,
19 I believe that the information that was generated can
20 not scientifically be supported.
21 Q. Are you aware of whether the District or
22 any other party, party generically, any other person
23 or entity, has attempted to validate or verify what
24 particular Kriging method is more appropriate for
25 Kriging phosphorus in rainfall?
141
1 A. I am unaware of anyone else validating the
2 various models.
3 Q. Is there a general consensus in the
4 scientific community regarding the appropriate
5 Kriging method for phosphorus in rainfall?
6 A. There is a consensus on the general
7 approach concerning the Kriging of wet deposition
8 data.
9 Q. What is that consensus?
10 A. The consensus I have described earlier is
11 using deposition information and using that to create
12 or using volume weighted concentration coupled with
13 rainfall information and Kriging both to then
14 determine deposition in the area that you are
15 interested in.
16 Q. You had indicated previously in part of
17 your testimony that you had attempted to obtain some
18 additional data from the District. What data are you
19 referring to?
20 A. Is your question regarding the Kriging or
21 regarding the wet deposition?
22 Q. I can do both. Let me back up and ask a
23 more general question. Is there any information that
24 you have requested that you have not received?
25 A. Yes.
142
1 Q. Tell me what that is.
2 A. We have requested background information
3 concerning the Kriging in terms of the models that
4 were used, how the models were fitted, what the
5 results of those fittings were in terms in the form
6 of graphics or tables. We have not received
7 anything.
8 Q. Do you know if any such things exist?
9 A. I do not know.
10 Q. Anything else you have requested but have
11 not received?
12 A. Yes.
13 Q. What?
14 A. Several times on December 18 counsel
15 requested from the District the volume information or
16 the amount of rainfall information associated with
17 each sample that was analyzed in the District's data
18 base for the 12 sites.
19 What we were sent or what counsel was sent
20 which was passed on to me was the diskette that I
21 previously described that is listed here that was a
22 1.8 megabyte file that contained every day's amount
23 of rainfall for a few sites and the data were, could
24 not be used. They were inappropriate.
25 Following that, counsel did request again
143
1 the information I have just described and
2 approximately ten days ago I received a diskette that
3 contained the volume information associated with the
4 bulk samplers as well as the event samplers for the
5 period of I believe 1974 through 1978 and then it
6 skips a year and a half, it goes from July 1978 until
7 the beginning of -- I am sorry, until 1988. Let me
8 back off from 1974 to the middle of 1988 and then it
9 skips a time period and then picks up again in 1990.
10 So therefore there is a void for what the
11 volume information was for those data that were
12 collected for that year and a half period.
13 Q. The '89-'90 time period somewhere?
14 A. Half of '88, all of '89.
15 Q. Do you know if that data exists anywhere?
16 A. I do not. Counsel has requested that
17 information.
18 Q. How would you use that information if you
19 receive it, if it exists?
20 A. If it were to exist, I would calculate the
21 volume weight concentrations.
22 Q. For what purpose?
23 A. To basically get an idea of what the
24 concentrations would have looked like on an annual
25 basis in a bucket. That could then be turned over,
144
1 turned into deposition data for those sites.
2 Q. Has the accuracy of the Kriging approach
3 for phosphorus ever been validated?
4 MR. BLANK: I object to the form of the
5 question.
6 You can answer it.
7 THE WITNESS: I am thinking of the answer.
8 (Pause)
9 A. Assuming an appropriate technique had been
10 used, no, not that I am aware of.
11 Q. Other than the three items that you
12 mentioned that you are basing your opinion on
13 concerning the inappropriateness of the District's
14 Kriging procedure, is there anything else that you
15 are relying on for that opinion?
16 A. I am sorry, there are several opinions
17 that I have talked about.
18 Q. As I understand it, you testified that in
19 your opinion the District's Kriging procedure was
20 inappropriate and that opinion was based upon
21 essentially I guess three sub-opinions, that the data
22 was inappropriate, the model itself was inappropriate
23 and the way the data itself was characterized was
24 inappropriate. Is there anything other than those
25 three items that support your opinion that the
145
1 Kriging procedure used by the District was
2 inappropriate?
3 A. No. That is pretty much what I based my
4 opinion on, but I would like to state that I did not
5 say that the model that was used was wrong, I said it
6 was impossible to determine whether it was even
7 correct, whether you should use ordinary Kriging
8 versus universal Kriging.
9 Q. What would you need to know to determine
10 which model is more appropriate?
11 A. You would have to actually have done
12 deposition calculations and doing that you then
13 looked at the period of record for each of the
14 monitoring sites and then determine whether or not
15 your data are sufficient to even Krig, whether you
16 even have enough data sites to even want to Krig to
17 determine the deposition in the area that you are
18 looking for.
19 Q. Are you saying you would volume weight the
20 rainfall phosphorus concentrations and then Krig
21 them?
22 A. There are two ways to do that. You
23 calculate the deposition at each site and use the
24 volume weight concentration with rain gauge reads
25 from other sites as well as the monitoring sites and
146
1 Krig both of them to get your deposition.
2 Q. And then multiply them?
3 A. Concentration with rain gauge amount.
4 Q. By using the approach you just described,
5 wouldn't that be multiplied errors, then?
6 A. Yes. But you have errors in everything
7 you do. I mean, it is a matter of doing it both
8 directions.
9 The concentration times amount carries an
10 error in the estimation for the concentration as well
11 as the estimation for the rain gauge reading and then
12 there is an error that you can carry over with
13 Kriging just using the deposition itself. And using
14 both ways you get an idea of what the relative errors
15 are, comparing one to the other.
16 Q. Why is it that you use volume weighted
17 concentrations?
18 A. Well, my opinion of why you need volume
19 weight concentration goes all the way back to
20 Walker's piece where he used the Everglades National
21 Park Research Center data that he obtained from the
22 District for the period late 1987 into early April
23 1989.
24 What he found was there was an inverse
25 relationship between the amount of rainfall and the
147
1 concentration of total phosphate. What I mean by
2 that is when you had heavy rains or there was heavy
3 rains the concentration was less than when you had
4 trace samples and the concentration was high.
5 What that says is that if you use an
6 arithmetic mean which the District did, you would
7 essentially end up with a different value than one
8 would get if you just wanted to calculate which is
9 what they were trying to do, find out what the
10 concentration was in the bucket over the period of
11 time they were interested in, from 1987 to 1989.
12 The only way you can do that is with the
13 volume weighted type concentration, because what it
14 does is give weighting to this problem associated
15 with the inverse relationship.
16 Q. Didn't the District provide information in
17 the SWIM Plan of both arithmetic as well as volume
18 weighted concentrations?
19 A. No.
20 Q. I assume what we just discussed, your
21 opinion concerning the Kriging procedure, is at least
22 one of the items covered under what you were asked to
23 do with regard to what has been done to date and your
24 conclusions, is that correct?
25 A. Could you, would you please? There are a
148
1 lot of ifs and buts in that.
2 Q. I will rephrase.
3 When I asked what you had been asked to do
4 by counsel you provided me with two things, one was
5 to look at what has been done to date and to draw
6 conclusions from that and secondly was opinions on
7 deposition rate.
8 A. Deposition amount.
9 Q. Other than the Kriging procedure opinion
10 that you have just expressed, what other opinions
11 have you reached with regard to what has been done to
12 date?
13 A. The table that is in the supporting
14 information document is incorrect.
15 Q. What table are you referring to?
16 A. The table that summarizes the flow
17 weighted mean column is that, that column does not
18 relate to whatever flow weighted means was supposed
19 to have meant.
20 Q. What you do you mean, it doesn't relate?
21 A. In the Grimshaw calculation or piece that
22 I referred to as an Appendix E in one of the reports,
23 there were several tables in there that were labeled
24 volume weighted concentration. They were in fact not
25 volume weighted concentration in those tables.
149
1 And that information was used in that
2 piece to carry over to form the table that appeared
3 in the supporting document.
4 Q. Are you saying that the table in the
5 supporting information document of the SWIM Plan
6 contains numbers which purport to be flow weighted
7 concentrations which in your opinion are not actually
8 flow weighted concentrations?
9 A. I had inferred that flow weighted mean was
10 the same as volume weighted concentration. I then
11 went back to the Appendix E and -- I am sorry. Let
12 me be careful, not the Appendix E in the SWIM Plan
13 but the appendix in the Grimshaw piece. And those
14 tables are labeled volume weighted but in fact they
15 are not the volume weighted values and that
16 information was then transferred into the information
17 in the SWIM Plan.
18 Q. Why do you say they were not, what are you
19 basing that on that they were not volume weighted
20 numbers?
21 A. Because volume had nothing to do with
22 those samples.
23 Q. How do you know that?
24 A. By looking at the data that were collected
25 from the District by Walker in his piece, he actually
150
1 listed in one of the tables, it may have been Table 1
2 or Table 2, the events data, meaning the two week
3 samples or the four week samples.
4 So I knew what the concentrations were of
5 total phosphorus in wet and dryfall.
6 By taking that information it is possible
7 then to compare that to the tables that were
8 constructed by Grimshaw in his Appendix E. And in
9 fact what he had, what Grimshaw had in his left
10 column was the average concentration, arithmetic
11 average concentration for individual months.
12 For example, he took all the January
13 numbers, all the February numbers, March numbers, no
14 matter what year it was, and he then had a table that
15 said for January the arithmetic average was value X
16 for two samples, that is an example, for February it
17 may have been three samples across several years, et
18 cetera.
19 What Grimshaw then did based on that is
20 reconstructed the numbers in the SWIM plan he sample
21 weighted. There were three samples in January,
22 multiplied it by the arithmetic mean and added to
23 that the two samples that may have been in February,
24 added it, and then divided by the total number of
25 samples at that site.
151
1 That is what is in the column that is
2 labeled flow weighted mean which is not volume
3 weighted concentration.
4 Q. Do you know whether the samples were in
5 effect the, consisted of similar volumes or not?
6 A. They did not consist of similar volumes at
7 least for the Everglades National Park site which
8 listed the volumes.
9 I will answer that in two ways.
10 What Walker used was rain gauge readings
11 from Homestead Air Force Base. That is different
12 than the volume, because he could not obtain from the
13 District the volume information.
14 Second, I have since received the volume
15 information recently from counsel that came from the
16 District through counsel and those volumes are
17 different.
18 Q. Different from what?
19 A. I think your question was do they vary
20 from sample to sample. They are different.
21 Q. Let me see if I have this right now.
22 You expressed the opinion that the table
23 in the SWIM Plan supporting information document
24 contains flow weighted mean numbers or purports to
25 which are taken from the Grimshaw document which in
152
1 your opinion do not actually reflect flow weighted or
2 volume weighted concentrations, is that correct?
3 A. My assumption -- I will answer that
4 question -- but my assumption is that flow weighted
5 means were the same as volume weighted means, given
6 that they were not volume weighted means.
7 Q. Just so I am clear, you are basing that on
8 the fact that you have obtained what the actual
9 volumes were in the samples?
10 A. No.
11 Q. Explain to me again how you know that they
12 were not volume weighted.
13 A. Because by using the data in the table
14 that Walker had, I was able to go to the table that
15 Grimshaw had for the Everglades National Park in that
16 particular Appendix E.
17 Given the data from November 1987 through
18 April, beginning of April of 1989 I was able to
19 reconstruct the Grimshaw table for the Everglades
20 National Park.
21 And what that means is the left column in
22 the Grimshaw table had something called phosphorus
23 concentration. That concentration that was listed
24 under the months of January, February, March, et
25 cetera, through December was the arithmetic mean of
153
1 the number of samples for each of those months across
2 several years. What Grimshaw then did was take the
3 number of samples that were made up in that
4 arithmetic mean and simply multiplied the two
5 together and then add it and divide by the total
6 number of samples. The volume had no role in any of
7 that calculation.
8 Q. Do you know whether the Walker data and
9 the Grimshaw data came from the same source, same
10 sampling?
11 A. Yes.
12 Q. Same data base?
13 A. Yes, because I was able to reconstruct the
14 Grimshaw table from using the Walker data.
15 I am sorry, when I say Walker data I mean
16 the data that Walker summarized that he had gotten
17 from the District, the exact number of samples, the
18 exact number of samples per month, everything matched
19 what was in the Grimshaw table.
20 Q. And Walker also reported volume in his?
21 A. No. He used the Homestead Air Force Base
22 rain gauge reading.
23 Q. Are you likewise then using the volume
24 that you determined from the Homestead rainfall gauge
25 to determine what the volume is?
154
1 A. I haven't done anything.
2 Q. You have not reanalyzed volume weighting
3 the numbers then, is that correct?
4 A. That is correct because we are waiting for
5 the data to come from the District for the incomplete
6 year and a half.
7 Q. You have not done that with regard to the
8 rest of the data, though?
9 A. You mean other sites?
10 Q. No, with regard to the park for other than
11 the year and a half that you are missing?
12 A. Could you rephrase that, please?
13 Q. Let's move on. I may come back to that.
14 What other opinions have you reached with
15 regard to what has been done to date?
16 A. It may be getting late and I may be
17 getting tired, but I am thinking, I am thinking I may
18 have covered all my conclusions concerning what has
19 been done to date. I would like to reserve the
20 possibility over the next period a light bulb goes
21 off and I am able to say yes, I forgot something.
22 Q. Okay.
23 With regard to the opinion we just
24 discussed concerning the information in the
25 supporting information document, are you relying on
155
1 anything other than what you just described,
2 comparison of the Walker numbers and the calculation
3 of the numbers in the Grimshaw report?
4 MR. BLANK: I object to the form of that
5 question.
6 Q. Other than what you just discussed, are
7 you relying upon anything else with regard to your
8 opinion that the information in the supporting
9 information document is incorrect concerning flow
10 weighted or volume weighted, assuming those are the
11 same?
12 A. There were also errors in that table,
13 there were transcription errors going from the
14 Grimshaw piece into the table in the SWIM Plan, there
15 was at least one site where the flow weighted mean
16 was incorrectly transcribed.
17 The data had been calculated in the
18 Grimshaw piece but somehow was incorrectly placed in
19 the table.
20 The other thing is that the Kriging used
21 arithmetic means, not the flow weighted means.
22 Q. I am sorry, say that again.
23 A. The Kriging used arithmetic means
24 according to the best information we had available in
25 the SWIM Plan, according to the SWIM Plan.
156
1 Q. Does that relate back to your first
2 opinion on the District using inappropriate Kriging
3 procedures?
4 A. Yes.
5 MR. NETTLETON: Please mark this as the
6 next exhibit.
7 (A document entitled The South Florida
8 Water Management District's Methods for the
9 Collection and Interpretation of the Quality and
10 Quantity of Rainfall, 27 September 1989, was marked
11 Lefohn Deposition Exhibit 3 for identification)
12 BY MR. NETTLETON:
13 Q. I have handed you what has been marked as
14 Exhibit No. 3. Is this the Grimshaw paper you have
15 been making reference to?
16 A. It is.
17 MR. NETTLETON: Mark that as No. 4.
18 (A document entitled Surface Water
19 Improvement and Management Plan for the Everglades,
20 pages 158 through 162, was marked Lefohn Deposition
21 Exhibit 4 for identification)
22 BY MR. NETTLETON:
23 Q. I am also showing you what has been marked
24 as Exhibit 4 which I will state for the record is an
25 excerpt from the supporting information document of
157
1 the Everglades SWIM Plan dated March 13, 1992.
2 Specifically it contains pages 158 through 162.
3 Is the information or the table that you
4 have been referring to with regard to your second
5 opinion included in this Exhibit No. 4?
6 A. 4 is, yes, one of the tables that I
7 referred to.
8 Q. Dr. Lefohn, with regard to Exhibit 4, can
9 you point out to me precisely which table it is you
10 are saying has the incorrect information concerning
11 flow weighted or volume weighted mean?
12 A. On Exhibit 4, the column that has been
13 labeled flow weighted mean --
14 Q. Which page are you on, sir?
15 A. Sorry, page 160, Figure 28. The flow
16 weighted mean column is not volume weighted
17 concentration.
18 Q. What table are you referring to in Exhibit
19 3 where this information was purportedly transferred
20 from?
21 A. I am sorry, in Exhibit 3 there were
22 several tables from which the table was purportedly
23 transferred from. Table 4, there is no page number,
24 is the table that I had used to reconstruct from the
25 Walker data how that, how Table 4 was created.
158
1 Q. What other tables from Exhibit 3 were
2 involved in the transposition over to Exhibit 4?
3 A. Well, Table 1 is the summary table of many
4 of the tables in Exhibit 3. You will notice on page
5 Exhibit 4, Figure 28, that the CLE site has listed
6 flow weighted mean of .033.
7 Q. Right.
8 A. If you look at Table 1 on the figure -- I
9 am sorry, on Exhibit 3, under CLE it is .186.
10 Q. That is the transcription error you were
11 referring to?
12 A. That is correct.
13 Q. Do you know what CLE station is?
14 A. Clewiston site.
15 Q. Have you reviewed the data to determine
16 which is the correct number?
17 A. Neither of them are correct. If you are
18 asking me if that was an error that went from the
19 Table 1 on Exhibit 3 over to Table 28, Table 1 is the
20 value that I -- the value in Table 1 was a value I
21 was able to reconstruct from the tables in the back
22 of Exhibit 3.
23 Q. I know we are all speculating at this
24 point but it obviously appears that the CLE site from
25 Table 1 on Exhibit 3, assuming it was transferred
159
1 over, the number that was included in Exhibit 4 is
2 actually for the one above it, B 50.
3 A. B 50.
4 Q. Is that correct? Is that what it looks
5 like?
6 A. You are speculating. It appears to be a
7 transcription error.
8 MR. NETTLETON: Please mark this as the
9 next exhibit.
10 (A document entitled Rainfall Total
11 Phosphorus Concentrations and Loadings in Everglades
12 National Park, prepared for Environ Corporation and
13 US Department of Justice, by William W. Walker, Jr.,
14 August 1989, was marked Lefohn Deposition Exhibit 5
15 for identification)
16 MR. NETTLETON: Off the record.
17 (Thereupon, a brief recess was taken,
18 after which the following proceedings
19 were had)
20 MR. NETTLETON: Back on the record.
21 BY MR. NETTLETON:
22 Q. Dr. Lefohn, have we handed you what has
23 been marked as Exhibit No. 5?
24 A. Yes.
25 Q. Is that the Walker paper you were
160
1 referring to previously in your testimony?
2 A. Yes.
3 Q. Can you tell me what you utilized from the
4 Walker paper or you relied upon to reach your
5 conclusion?
6 A. Page 6, Table 1.
7 Q. Can you tell me how this table was used by
8 you to determine that the information contained in
9 the SWIM Plan was incorrect?
10 A. What I did was I looked at Table 4 of what
11 I am calling the Grimshaw piece.
12 Q. That is Exhibit No. 3?
13 A. That is correct. And I segregated the
14 data by month independent of the year.
15 For example, if you look at June on Table
16 4 and you then refer to Table 1 of Exhibit 5, under
17 June there were only, on Table 1, there are only two
18 entries, June 8, 1988 and June 29, 1988.
19 In the fourth column there is a total that
20 is listed on that table for June 8, 1988. It is .004
21 ppm. And on June 29, 1988 it is .10.
22 I added the two values together and took
23 the simple arithmetic mean of the two values. The
24 addition of the two is .014 parts per million. I
25 divided that by 2 which is .007 parts per million.
161
1 On Table 4 the entry in the first column
2 under total phosphorus concentration is .007 which is
3 the arithmetic mean of those two values.
4 Likewise, if you segregate the samples by
5 month you can get the left column, the information in
6 the left column in Table 4 from Table 1.
7 Q. Okay.
8 A. Now given that information, if you then,
9 now referring to Table 4 in Exhibit 3, if you
10 multiply, for example, looking at the month of
11 January, .054 which is the arithmetic mean of three
12 samples, times 3, and you add to that .025 times 1,
13 and you add to that .034 times 3, and you keep doing
14 that all the way through December, you are
15 essentially adding together 12 products of each one
16 representing sample size times the average
17 concentration.
18 I then get a sum from that total and I
19 divide that by the sample size.
20 That value for the Everglades National
21 Park --
22 Q. Can I stop you there for a second?
23 A. You may.
24 Q. When you say you divide by the sample
25 size, what do you mean?
162
1 A. I mean if you go to the third column it
2 says sample size and add.
3 Q. To the number of samples?
4 A. Yes.
5 You then -- there are 23 samples and if
6 you then go to Table 1 of Exhibit 3 you will see the
7 entry under sampling station ENP of .034 in the right
8 column under volume weight. That is not a volume
9 weighted concentration, that is a sample weight
10 concentration.
11 Q. Am I correct then that if you take the
12 numbers on Table 4, multiply the first column by the
13 third column, add up the totals of each of those and
14 divide that sum by the total number of samples you
15 come up with .034?
16 A. Yes. That's a sample weighted mean.
17 I did that same calculation for each of
18 the other sites, not using the Walker paper but using
19 just the tables in the Grimshaw piece.
20 Q. I am sorry, without using the Walker?
21 A. There is no reason to use the Walker paper
22 because the Walker paper only dealt with Everglades
23 National Park.
24 So there are additional tables there that
25 I think are before Table 4 and after Table 4 that you
163
1 could then reconstruct the information that was
2 summarized in Table 1 under the column volume weight
3 which is not volume weight.
4 Q. What else did you use the Walker paper
5 for, if anything?
6 A. What I used the Walker paper for also for
7 Table 1 was to convince myself that the District data
8 that it had given me for rain gauge values for every
9 day was useless information, i.e., I couldn't use it
10 for my purposes which was to calculate the
11 precipitation weighted mean. And that was because I
12 did not know when the start date was for each sample.
13 Table 1 has an item A, footnote A -- on
14 the first line, 11/17/87 -- and that footnote states,
15 11/01/87 starting date assumed.
16 I believe Walker had the same problem I
17 had which was he did not know when the sample started
18 and so he assumed a starting date.
19 Based on his assumption and based on the
20 fact that I had already reached that conclusion that
21 assumptions would have to be made, I decided that the
22 data that had been given to me by the District could
23 not be used to calculate precipitation weighted means
24 based on the daily rain gauge values.
25 Q. Going back to Exhibit 3 and Table No. 1 --
164
1 A. Yes.
2 Q. -- have you done any analysis to determine
3 how the numbers reached under the column labeled
4 Simple have been reached or calculated?
5 A. Yes. Simple --
6 Q. Before you answer that, let me strike the
7 question and ask you a preliminary question.
8 Is what you just described as occurred is
9 it reflected under the volume weighted column under
10 Table 1, would you consider that a simple arithmetic
11 mean?
12 A. No.
13 Q. Okay, then I will repeat my original
14 question which is have you done any analysis to
15 determine how the number under the sample column has
16 been calculated.
17 A. Yes. The sample column or -- some
18 preliminary analysis using the data that had been
19 given to me from counsel that had come from the
20 District's data set appears to be simple arithmetic
21 mean. And that is in fact what shows up in Exhibit
22 4, Figure 28 under the column, simple arithmetic
23 mean, which is the third column of Table 4.
24 Q. Describe for me the difference between a
25 simple arithmetic mean and a sample weighted mean.
165
1 A. A simple arithmetic mean simply takes all
2 the numbers and adds them up independent of trying to
3 weight a particular month more than another, it
4 simply treats all the data together, it simply, you
5 go from start to finish, whereas if you had an
6 average that occurred in the month of January, you
7 had 15 samples in that month, you would weight that
8 month of January more than some other month if 15
9 were the highest number of samples that were measured
10 in that month.
11 So you are giving more weight to those
12 months that add more samples. That has nothing to do
13 with volume.
14 Q. Now that it has been a little bit longer,
15 let me go back to a question I asked you before.
16 Other than the two areas we have
17 discussed, have you reached any other opinions
18 concerning what has been done to date by the
19 District?
20 A. Nothing more than I have already discussed
21 today.
22 Q. Are you relying upon anything in the
23 Walker document, Exhibit No. 5, other than Table 1
24 that we have talked about?
25 A. To reach the conclusions that I have
166
1 already talked about?
2 Q. Yes, sir.
3 A. No.
4 Q. In Exhibit No. 4 which is the excerpt from
5 the SWIM Plan supporting information document, is the
6 information concerning Kriging that you referred to
7 with regard to your first opinion contained in this
8 excerpt?
9 A. Yes, most of it.
10 Q. Can you tell me where that is?
11 A. I believe page 162. There is no page
12 number on the page previous to 162 which I assume is
13 page 161. In the last paragraph it starts out with
14 saying a statistical procedure was employed.
15 Q. And that through the first full paragraph
16 on 162 is the information you recall referring to?
17 A. Yes. And additional -- perhaps the next
18 paragraph also, Table 16.
19 Q. Is it your understanding that the
20 information contained in Table 16 is the result of
21 the Kriging exercise employed by the District?
22 A. I believe so.
23 Q. With regard to Exhibit 3, the Grimshaw
24 1989 paper, other than the sections or tables we have
25 discussed, are you relying upon anything in that
167
1 document for the conclusions you have expressed other
2 than that which we discussed?
3 A. Yes. There are additional tables which I
4 referred to but did not name that were before and
5 after the Everglades National Park summary table.
6 Q. And that is with regard to the, I think
7 you mentioned that if you went through each of the
8 tables for each of the stations you could add them up
9 and do the same calculations --
10 A. That's correct.
11 Q. Anything other than the tables in the
12 Grimshaw 1989 document that you relied on?
13 A. I would like to take a second.
14 Q. Sure.
15 (Pause)
16 A. I believe that is it.
17 Q. The second area that you indicated counsel
18 had asked you to express an opinion on was opinions
19 on, I originally had written down deposition rate in
20 South Florida but then I think you said that should
21 be deposition amount.
22 A. Yes.
23 Q. What is the distinction you are making
24 between rate and amount?
25 A. Amount would be the total value that one
168
1 would get over the year. A rate is a function of
2 time of some sort. And I am just saying the average
3 of a year or something like that would be the amount
4 of deposition.
5 Q. When you say the amount of deposition, are
6 you talking essentially volume of water or --
7 A. No. The kilograms per hectare of the
8 total phosphorus that occurred in the area.
9 And then from that you get a loading value
10 which is your -- which is in Table 16 in Exhibit 4.
11 Q. In deposition are you talking about both
12 wetfall and dryfall?
13 A. Yes, total.
14 Q. Have you formulated an opinion concerning
15 the deposition amount of total phosphorus in South
16 Florida?
17 A. Not at this time.
18 Q. Can you tell me what you have done toward
19 that goal?
20 A. It is a matter of identifying the or
21 attempting to obtain the volume weighted
22 information -- the volume information from the
23 District which as I indicated previously we have some
24 of those data.
25 In addition, I have attempted to locate
169
1 other data sets that may be some help in the future.
2 Q. What other data sets are you attempting to
3 locate?
4 A. Well, I have located the National Acid
5 Deposition data for phosphorus for the six sites in
6 Florida.
7 Q. That is the NADP?
8 A. NADP.
9 Q. Any other data sets?
10 A. Just a copy of an article that appeared by
11 Hendry, Brezonik and Edgerton that I already referred
12 to.
13 I do have some other data that relates to
14 the EPRI data base and some of the UAPSP data and I
15 have not looked at that yet.
16 Q. Have you formulated any preliminary
17 opinions at this point concerning the deposition
18 amount of total phosphorus?
19 A. No.
20 Q. The volume information you are referring
21 to is that year and a half of data, the '88 and '89
22 that you discussed earlier?
23 A. Yes, that is correct.
24 I would like to clarify something very
25 quickly. It was the other data set also from the
170
1 USGS that I have, the three months that I previously
2 referred to earlier today.
3 Q. Do you have any other data from the USGS
4 other than the 1992 three months of data?
5 A. I don't believe so. I don't think so at
6 this time.
7 Q. Do you intend to look at any earlier USGS
8 data?
9 A. If I can be convinced based on
10 recommendations from others concerning that the
11 quality of the data are adequate I would certainly
12 want to look at it if volume data were available.
13 Q. What have you heard concerning the quality
14 of the USGS data?
15 A. Well, we are talking about a lot of USGS
16 data, some of it going back to 1965 and earlier than
17 that. The summaries were for '65.
18 It seems to have similar problems as other
19 data bases have suffered from concerning the early
20 type of monitoring that went on. There was no
21 indication in the '65 report there was any volume
22 information so even if the quality were okay, were
23 appropriate, I am not sure it would be useful.
24 Q. Is the three months that you have from
25 1992, does that include volume data?
171
1 A. Yes.
2 Q. Do you know what the quality of that data
3 is?
4 A. No. I did not work on those data because
5 we have no documentation associated with receiving
6 those data. We are waiting for that.
7 Q. Do you know when that is going to occur?
8 A. No.
9 Q. What is your opinion as to the quality of
10 the NADP data?
11 A. For what it was intended to do, I think
12 the data are adequate. The quality assurance
13 protocol was very rigorous.
14 Q. With regard to the NADP data, am I correct
15 that you will be looking solely at the
16 orthophosphorus parameters?
17 A. No. I may look at other things but it is
18 premature at this time. I have a full set of data
19 that came from the 12 sites -- six sites in Florida.
20 Q. What other aspects of the NADP data will
21 you be looking at?
22 A. I don't know. That's what I am saying, I
23 have the ions, cations and anions data and it is a
24 matter of looking at patterns of type of exposures
25 that occurred during those weekly samples.
172
1 Q. How would that assist you in formulating
2 your opinion on total deposition of total phosphorus
3 amounts?
4 A. It may not. Once again, that is only
5 orthophosphate that they measured so therefore to get
6 to the total phosphorus just may not be appropriate.
7 Q. Do you have an opinion as to quality of
8 the NADP data concerning orthophosphate?
9 A. There may be some question concerning the
10 degradation of the samples.
11 Q. What is the question?
12 A. In terms of the integrity of the data, was
13 the sample adequately preserved so that you did not
14 have problems with biological activities occurring
15 within the sample that resulted in less sample being
16 measured than was actually there at the beginning.
17 Q. Do you have any opinion on that question
18 at this point?
19 A. Not at this point.
20 Q. Do you intend to formulate an opinion?
21 A. Yes.
22 Q. What type of activities, I think you
23 described them as biological activities, would affect
24 the integrity of the data on orthophosphorus?
25 A. The actual biological activity I can not
173
1 define for you. However, there may be indications of
2 degradation of the sample and what I want to do is
3 talk with the investigators in Illinois who were
4 responsible for doing the analysis as well as the
5 quality control process to find out if they have
6 looked at the issue and what their conclusions are.
7 Q. Have you talked to anybody at, is it the
8 University of Illinois?
9 A. Yes, it is the University of Illinois.
10 Q. Have you talked to anybody concerning
11 this?
12 A. Concerning phosphorus analysis, yes.
13 Q. Who have you talked to?
14 A. Dr. Van Bowersox who sent me a paper.
15 Q. He is the one who authored the acid rain
16 paper?
17 A. Yes.
18 Q. What is his role with regard to the
19 analysis of the NADP data?
20 A. I don't know his official title but he's
21 very prominent in terms of how the data are analyzed,
22 how they are stored in the computer data base and how
23 adequate the data are for various types of analysis.
24 Q. How often have you spoken with him
25 concerning this matter?
174
1 A. Twice.
2 Q. When were those conversations?
3 A. Probably in November, in the early part of
4 my analysis and probably about four weeks ago or five
5 weeks ago when I asked for a copy of his paper.
6 Q. Have you had any correspondence with him
7 concerning this?
8 A. Just when he sent me the original set of
9 information concerning how they analyzed for
10 phosphorus.
11 Q. I am sorry, what did he send you?
12 A. The information on how they analyzed for
13 phosphorus from the EPA regulations.
14 Q. What form did that take? Was that an
15 EPA --
16 A. Xerox copies of EPA material on the
17 protocols.
18 Q. Did he send you any other material?
19 A. Not that I can recall.
20 Q. Did he send a cover letter with the
21 material?
22 A. Yes.
23 Q. Did he state anything other than,
24 enclosed?
25 A. No, typical, enclosed please find.
175
1 Q. In any of your discussions or
2 correspondence did he ever express an opinion as to
3 the quality of the data concerning the
4 orthophosphorus?
5 A. Just that in many samples across the
6 United States they were measuring many times minimum
7 detectable levels at many sites across the United
8 States.
9 Q. Can you explain to me, what does that
10 mean?
11 A. It meant low values at many sites across
12 the United States. We didn't talk about any specific
13 location but just that the values were low in
14 general.
15 Q. I guess just so I am clear, are you saying
16 he stated that the levels of orthophosphorus shown in
17 the data across the United States are at around the
18 detection limit, is that --
19 A. Many of the samples that they had gathered
20 at many of the sites across the United States were at
21 or below minimum detectable levels which means it
22 could be there but they weren't sure how much.
23 Q. Do you know what minimum detection levels
24 he was referring to?
25 A. Well, the absolute values seem to vary
176
1 over the years. It may be somewhere in the area of
2 two parts per billion.
3 Q. Is this data with regard to wetfall or
4 bulk?
5 A. Wetfall. What I was discussing with him
6 was wetfall.
7 Q. Are you aware of whether NADP has any data
8 concerning orthophosphorus or total phosphorus in
9 dryfall?
10 A. I believe there are data, some data. I do
11 not know what the data of record looks like.
12 Q. Have you discussed any of that with, what
13 is his name?
14 A. Van Bowersox, Dr. Van Bowersox.
15 Q. With Dr. Van Bowersox?
16 A. No, I did not.
17 Q. Have you spoken with anyone else at the
18 University of Illinois or anyone who is involved in
19 the analysis of the NADP data?
20 A. No.
21 Q. Have you sent any correspondence to the
22 University of Illinois or anyone involved in the
23 analysis of the NADP data?
24 A. Pertaining to this case, no.
25 Q. Did Dr. Van Bowersox discuss any other
177
1 matters with you that might be related to this case
2 other than the data we just discussed?
3 A. No.
4 Q. Are you able to form an opinion concerning
5 the deposition amount of total phosphorus with the
6 data you currently have for any particular time
7 period?
8 MR. BLANK: For what area, counsel, South
9 Florida?
10 Q. I am sorry, for South Florida, the
11 Everglades area.
12 A. I can not at this time calculate a number
13 that I would believe in.
14 Q. If the year and a half of data concerning
15 volume from half of '88 and '89 does not exist would
16 you be able to formulate an opinion concerning the
17 deposition amount of total phosphorus in South
18 Florida?
19 A. I could certainly do the calculations for
20 the time period of record where volume data were
21 there for various sites. I would feel more
22 comfortable comparing those data with an independent
23 set of data to see if similar patterns were observed.
24 And then based on that I could begin to draw
25 conclusions.
178
1 Q. What independent set are you referring to?
2 A. Data that may exist through the published
3 information from the Hendry data from the late
4 seventies. I do not know if it continued into the
5 eighties but at least the late 1970s time period,
6 taking a look at some of the wet orthophosphorus data
7 for NADP and then attempting to correlate that with
8 some of the absolute values that have been measured
9 at some of the six sites of data or some of the 12
10 sites of data, six wet-dry sites.
11 Q. Have you attempted to do that to date?
12 A. No. I was waiting for more data, more
13 volume data from the District.
14 Q. What other scientists besides yourself
15 have you discussed the issue of total phosphorus
16 amounts in deposition in South Florida with?
17 A. In general, with Dr. Krupa, Dr. Sagar
18 Krupa, in general.
19 Q. Anyone else?
20 A. Not deposition amounts.
21 Q. Can you tell me what your discussions with
22 Dr. Krupa have consisted of?
23 A. Namely the quality of the data.
24 Q. And Dr. Krupa, I believe you previously
25 testified, is someone you subcontracted to look at
179
1 the QA/QC of the data, is that right?
2 A. That's right.
3 Q. Has Dr. Krupa expressed any opinions to
4 you concerning the deposition amount of total
5 phosphorus in South Florida?
6 A. No.
7 Q. Have you expressed any opinions to Dr.
8 Krupa concerning that?
9 A. Only the problem of not being able to have
10 the volume information available.
11 Q. Have you discussed with him any
12 preliminary opinions based on the data that you do
13 have on hand?
14 A. No. Well, not the phase one that we
15 talked about, what we talked about previously.
16 Q. Phase one meaning your opinions concerning
17 the work that has been done so far by the District?
18 A. Yes.
19 Q. Has Dr. Krupa expressed any opinions to
20 you concerning that phase one area?
21 A. Of the questions that I was asking, no.
22 Q. Have the opinions that you expressed to
23 Dr. Krupa concerning that phase one area been
24 consistent with what you have told us here today?
25 A. Yes.
180
1 Q. If there are no data for volume of
2 rainfall in the same area as the sampling site for
3 total phosphorus, are you able to determine the total
4 phosphorus amount in deposition?
5 A. For that particular site?
6 Q. For that particular site.
7 A. If the volume data did not exist and the
8 rain gauge data did not exist then the volume
9 weighted or precipitated weighted values could not be
10 determined.
11 Q. How close in proximity must the data on
12 volume exist in order for you to be able to draw a
13 scientifically valid conclusion, in your opinion?
14 A. NADP focused on the precipitation as its
15 prime calculation to calculate a weighted value. It
16 then, if those data were not available, precipitation
17 rain gauge, it went to a volume value. If those data
18 were not available they did not bother to make the
19 calculation, include the sample.
20 Q. Does the NADP sampling sites all have
21 gauges at the same site the samples are taken from?
22 A. Yes.
23 Q. Is it your opinion that in order to
24 formulate a conclusion or opinion that you would need
25 data on, from gauges at the same site as the sampling
181
1 site?
2 A. Concerning calculating volume weighted or
3 precipitation weighted, that would be my opinion.
4 Q. If the District sampling sites, meaning
5 the South Florida Water Management District sampling
6 sites which produced the data concerning total
7 phosphorus concentrations do not also have
8 contemporaneous gauge readings or volume readings, is
9 there any means in your opinion to calculate volume
10 weighted total phosphorus in deposition in South
11 Florida?
12 A. That's a hypothetical question in that
13 they do have volume for some years in some samples so
14 it is possible for specific locations to calculate a
15 volume weighted concentration for a specific amount
16 of time.
17 The concern that I would have is are there
18 sufficient data covered in a particular year, set of
19 years to be able to use those data to estimate what
20 the deposition would be in the WCA area or any other
21 area of interest where you would interpolate using
22 the information. So you can calculate, I can
23 calculate, others can calculate the volume weighted
24 concentration for specific sites for specific time
25 periods at this time.
182
1 Q. But you haven't done that to date, is that
2 right?
3 A. That is correct, I have not done that.
4 Q. Do you agree with the NADP approach of
5 using volume if gauge measurements are not available?
6 A. Yes.
7 Q. Absent contemporaneous, what I mean by
8 that, in the same location, gauge or volume data, is
9 it possible in your opinion to use data from gauges
10 further away from the sampling site and how far away,
11 if possible?
12 A. It is risky at best because talking with
13 some of the people that live in this area, they talk
14 in terms of a large degree of variation in the amount
15 of rainfall over short distances. Therefore, to come
16 up with a formula that says X number of miles away is
17 acceptable and anything greater than that is not
18 acceptable is very risky.
19 Q. Have you ever done that with regard to
20 this or any other analysis you have conducted?
21 A. No.
22 Q. How does the taking of the volume versus
23 the gauge data bias the result, if it does?
24 A. The estimate from NADP is that the rain
25 gauge value represents a more complete data capture
183
1 than the volume. So therefore, assuming that
2 assumption or statement or given that NADP uses, if
3 you use volume you may be underestimating the amount,
4 the deposition that occurred during that event.
5 Q. The amount of the phosphorus?
6 A. Or any other chemical that you are
7 interested in.
8 Q. Do you agree with that assessment by NADP?
9 A. I think based on the analysis that they
10 have done, I do believe that.
11 Q. Do you have a time frame in mind of when
12 you intend to reach opinions concerning the second
13 phase of your work?
14 A. I would like to be finished sometime
15 during the summer, early summer. A lot of that is
16 contingent upon being just to being able to obtain
17 the information we have asked for in a timely
18 fashion.
19 Q. Have you been instructed not to formulate
20 any opinions based upon the data that is available
21 until you receive this additional year and a half of
22 data on volume?
23 A. No, that was my decision.
24 Q. In your opinion, how many stations would
25 be necessary to calculate a real phosphorus
184
1 deposition amount?
2 MR. BLANK: Could you repeat the question?
3 Are you saying areal?
4 MR. NETTLETON: Areal, sorry.
5 A. I don't have an opinion on that because
6 what that would depend upon would be how closely the
7 summarized data of each site as you compare site to
8 site fit the assumptions that are built into Kriging
9 and that from that you then do the variogram, go
10 through all the motions and from that you could
11 basically say how many sites could I take out and
12 still have something within a degree of confidence of
13 some defined level. So I don't feel comfortable in
14 giving you a certain answer at this point, it will be
15 variable according to the data.
16 Q. What assumptions are you talking about?
17 A. The assumptions have to do with the
18 continuity of the samples meaning you don't have big
19 jumps in values from station to station.
20 Kriging is based, was originally used for
21 mining purposes for purposes of core samples and
22 estimating what the concentrations were like at a
23 particular location. And consequently there were
24 certain assumptions built into the mathematics that
25 says this is a smooth transition, as you go from site
185
1 to site you don't have a low value, high value, low
2 value.
3 One of the assumptions is that it is
4 continuity, that it is continuous.
5 Another is that there is not necessarily a
6 trend in the data in terms, trend in the data has to
7 do with drift in the data and that is a mathematical
8 term the Krigers use and that's why they would go to
9 something like universal Kriging versus ordinary
10 Kriging. They look at the data points, they then
11 take a look at the pattern and then say do these
12 assumptions fit.
13 Q. Do you have an opinion of whether or not
14 using the data that may be available from the NADP
15 stations in Florida would be a sufficient number of
16 data points or sampling sites in order to reach an
17 opinion concerning the amount of total phosphorus in
18 deposition in Florida?
19 A. The amount of total phosphorus was not
20 measured by NADP so there has to be jumps or leaps of
21 faith to get there.
22 Q. Assuming they had measured total
23 phosphorus or change it to orthophosphorus. My
24 question is more directed to in your opinion are the
25 number of sampling sites sufficient.
186
1 A. No, those sites were spread out all over
2 the state.
3 Q. So in your opinion they would not be a
4 sufficient number?
5 A. By themselves.
6 Q. Can you tell me what you base that opinion
7 on?
8 A. That's based on the fact that you are
9 attempting -- it is similar to what we did out in the
10 United States when we were asked to estimate the
11 ozone levels across the United States.
12 We had samples in Utah and in Denver that
13 we were using to estimate what the values were in
14 Montana and Wyoming.
15 Obviously there was an air bound that was
16 equal to the magnitude of the value we were trying to
17 estimate.
18 The same situation would exist here, is
19 that you are talking about three WCAs that, I assume
20 that you are trying to determine what the area
21 loading is to those three areas. And that you have
22 sites up at Bradford and Austin Cary which is the
23 northern parts of the state, you have Cape Canaveral
24 and Quincy and Everglades National Park.
25 That is spread out throughout the entire
187
1 state and what you are doing is taking points way up
2 to the north and saying I am going to use those to
3 estimate down in the southern part of Florida. If
4 you have a density enough through the entire state
5 beyond the six sites perhaps those six sites coupled
6 with others could give you the information. By
7 themselves they would not be appropriate.
8 Q. How many sites would you need?
9 A. I think I answered that already in terms
10 of it depends on the data and the variability as you
11 look at the assumptions. There is not a quick
12 formula that says X number is what you need to do.
13 Q. If the data you collect from the existing
14 NADP sampling sites establish that the assumptions
15 corresponded or the numbers were relatively even,
16 would you then be of the opinion that you could use
17 those sampling sites, they would be sufficient to
18 determine total phosphorus deposition?
19 A. I wouldn't feel comfortable because you
20 would only be able to draw upon a couple of sites
21 that are in the middle and southern part of the state
22 to be able to draw conclusions because the further
23 you are away the less they are, those sites are going
24 to participate in your decision of what the
25 deposition is.
188
1 Q. Then it would seem to me that you must
2 have some opinion of how far apart they can be then
3 before you would feel comfortable using them.
4 A. No, because you are asking for a real
5 number. I can't give you a real number at this
6 point.
7 Q. We know the number that exists is too
8 much, the distance.
9 A. We have six sites. What I am saying is to
10 Krig those six sites to tell you what the world is
11 like in Southern Florida I believe would be
12 inappropriate, if those sites, those data are taken
13 by themselves.
14 Q. Do you believe in your opinion are the
15 sampling sites that exist within the District's
16 network sufficient, assuming you have the data that
17 is necessary, to form an opinion concerning the total
18 phosphorus deposition in Southern Florida?
19 A. Taken alone by themselves, I would feel
20 uncomfortable in depending just on those data. Even
21 if the data coverage, meaning the time period were
22 enough overlap that I could have seven or eight sites
23 taken over the same year, I could then -- and volume
24 was available, but the Grimshaw paper questioned the
25 volume from the District. That doesn't mean the data
189
1 are horrible and can't be used but it means you would
2 look to other data and compare the pattern from the
3 other data with the data from the District.
4 Q. I am not sure you answered my question
5 though. Are the number of sampling sites sufficient
6 in your opinion, assuming the quality of the data, in
7 order to reach a conclusion?
8 A. I believe the conclusion I reached and Dr.
9 Knudsen reached, given the lack of overlap, that we
10 have a great question of whether or not there are
11 enough data out there at any given moment to be able
12 to Krig.
13 In other words there was data starting in
14 '74, '75 for some sites that disappeared right then,
15 the Homestead base had three samples, I believe.
16 That certainly is not representative of that
17 location.
18 Q. Are you saying that even assuming you
19 receive this year and a half of data on volume, that
20 you do not believe you will be able to form an
21 opinion in any event concerning the total phosphorus
22 deposition amount in South Florida?
23 A. No, that is not what I am saying. What I
24 am saying is given the volume information, I can at
25 least calculate the volume weighted concentration for
190
1 sites for particular year. Based on that I can then
2 take a look and see where those sites are in
3 comparison to WCA and then make that decision whether
4 or not there are sufficient sites near the WCAs to
5 Krig into there.
6 Q. If you