Table VI. Replicate Collections of Toxaphene on Polyurethane Foam and Tenax-GC Resin polyurethane Tenax-GC resin
X, ng/rn3 collect. date
(no. of samples)
% re1 SO
5/9/77 17.0 0.444 (3) 5110177 12.0 0.472 (3) 6/9/77 10.0 1.19(2) 8/31/77 66.3 (3) 9.8 9/19/77 1.72(3) 16.0 10112/77 1.31 (2) 6.1 12/23/77 3.08 (3) 4.0 8/31/78 18.4 (1) 9/6/78 26.0 (1) 9/12/78 15.3 (1) 9/14/78 60.5 (1) 3/7/79 1.01 (2) 16.6 3/17/79 1.10(2) 5.1 5/21/79 3.23 (2) 3.1 7/14/79 3.92 (1) 19.7 (1) 8/14/79 32.7 (1) 8 I 22 I 79 ~means:
15.1
10.0
(no. of samples)
% re1 SO
17.6 (1) 26.4 (1) 15.3 (1) 42.2 (1) 1.58 (3) 13.1 0.97 (3) 18.2 3.72 (2) 7.6 4.15 (3) 7.0 20.3 (1) 30.8 (1)16.3
11.5
100(Tx - PPF) Tx
-4.7 4-1.8 0.0 -43.3 $35.6 -13.4 4-13.2 +5.5 +3.0 -6.2 -0.9
triplicate set was sufficiently different from the others to result in larger relative standard deviations (see Table 11, 31 17/79, Tenax; Table 111,317179,Tenax; and Table IV, 9/19/77, PPF). The fact that poor precisions on a given day were associated with an individual CHC and not with the five types of compounds collected indicates that analytical errors and not sampling problems were responsible. T o evaluate analytical precision, a “synthetic air sample” containing 380 ng of HCB, 4560 ng of Aroclor 1016,4540 ng of Aroclor 1254,550 ng of p,p’-DDE, 810 ng of p,p’-DDT, 440 ng of cis-chlordane, 430 ng of trans-chlordane, and 3070 ng of toxaphene was prepared and analyzed after silicic acid fractionation. Relative standard deviations for five replicates ranged from 10 to 15% for the individual CHC, with recoveries ranging from 75 to 95%. Average relative standard deviations for the field samples collected on PPF’ or Tenax ranged from 8 to 22% (Tables II-
VI), including the few sets with considerably poorer precisions, and were of the same magnitude as the analytical precisions. Thus the limiting factor in obtaining precise values for airborne CHC appears to be analytical, not sampling. Literature Cited (1) Lewis, R. G. In “Air Pollution from Pesticides and Agricultural Processes”; Lewis, R. G., Lee, R. E., Eds.; CRC Press: Cleveland, 1976: ChaDter 3. DD 51-94. (2) Bidleman, T . F.F:;’Olney,C. E. Bull. Enuiron. Contam. Toxicol. 1974,11, 442-450. (3) Rice, C. P.; Olney, C. E.; Bidleman, T. F. World Meteorological Organization Special Environmental Report No. 10, WMO-460, 1977, pp 216-224. (4) Turner, B. C.; Glotfelty, D. E. Anal. Chem. 1977,49, 7-10. (5) Lewis, R. G.; Brown, A. R.; Jackson, M. D. Anal. Chem. 1977,49, 1668-1672. (6) Stratton, C. L.; Whitlock, S. A.; Allan, J . M. U.S.Environmental Protection Agency, Research Triangle Park, N.C., 1978, EPA Report 600/4-78-048. (7) Simon, C. G.; Bidleman, T. F. Anal. Chem. 1979, 51, 11101113. (8) Zlatkis, A.; Lichtenstein, H. A.; Tishbee, A. Chromatographia 1973 6, 67. (9) Bertsch, W.; Chang, R. C.; Zlatkis, A. J . Chromatogr. Sei. 1974, 12, 175. (10) Pellizzari, E. D.; Bunch, J. E.; Carpenter, B. H. Enuiron. Sei. Technol. 1975.9, 552-560. (11) Pellizzari, E. D.; Bunch, J. E.; Berkley, R. E.; McRae, J. Anal. Lett. 1976,9, 45-63. (12) Svdor, R.: Pietrzvk. D. J . Anal. Chem. 1978.50. 1842-1847. (13) V;dal-Madjar, C:; Gonnord, M. F.; Benchah, F.’; Guiochon, G. J . Chromatogr. Sci. 1978,16, 190-196. (14) Bidleman, T . F.; Billings, W. N.; Simon: C. G. Final Report to EPA Contract 804716-01,1980. (15) Bidleman, T . F.; Matthews, J. R.; Rice, C. P.; Olney, C. E. J . Assoc. O f f .Anal. Chem. 1978,61, 820-828. (16) Murphy, P. J . Assoc. O f f .Anal. Chem. 1972,55, 1360-1362. (17) Veierov, D.; Aharonson, N. J . Assoc. Off. Anal. Chem. 1978,61, 253-260. (18) Klein. A,; Link, J. D. J . Assoc. Off. Anal. Chem. 1970, 53, 524-529. (19) Bidleman, T. F.; Olney, C. E. Nature (London) 1975, 257, 475-477. (20) Harder, H. W.; Christensen, E. J.; Matthews, J.; Bidleman, T. F. Estuaries, in press. (21) Seiber, J. N.; Madden, S. C.; McChesney, M. M.; Winterlin, W. L. J . Agric. Food Chem. 1979,27, 284-291.
Received for reuieu: October 9,1979. Accepted February 11,1980, This work u a s supported by U S . Eniironmental Protection Agency Contract No. 804716-01. Contribution No. 331 of the Belle W . Baruch Institute.
Potential for Changing Phytoplankton Growth in Lake Powell due to Oil Shale Development Mary L. Cleave”, Donald B. Porcella’, and V. Dean Adams Utah Water Research Laboratory, Utah State University, Logan, Utah 84322
The development of the oil shale industry will produce large quantities of spent shale for disposal, as well as cause largescale disruption of the soil overburden and raw oil shale strata in the Intermountain West ( I 1. The raw and spent oil shale and soil overburden of these areas all contain high levels of salt (2). Percolation of water through these disrupted components would cause increased salinity in the Colorado River ( 3 ) . Percolation of water could be caused naturally due to prePresent address, Tetra Tech, Inc., 3700 Mt. Diablo Boulevard, Lafayette, Calif. 94549. 0013-936X/80/0914-0683$01 .OO/O
cipitation, or artificially with the use of process water to stabilize the processed shale disposal sites after compaction ( 4 ) . These disposal sites will be designed as total containment systems ( 5 ) . Failure to contain all of this leachate due to seepage from the bottom of the containment basins or during periods of heavy precipitation could allow this leachate to enter the drainage system of the area. Along with the addition of salt, the leaching process through the raw and spent oil shale could potentially load both organic compounds and heavy metals into the contacted drainage system. Trace elements are present within the waste, but of these
@ 1980 American Chemical Society
Volume 14, Number 6, June 1980
683
The potential effects of oil shale leachate and salinity additions on the productivity of freshwater algae were studied in laboratory studies using batch bioassays. These batch bioassays were used to screen variations of water extractions of different processed and unprocessed oil shales, and the concentration effects of both the salts and the oil shale extractions on the growth of indigenous algae from Lake Powell. The batch bottle bioassays were conducted following the
standard algal assay procedure as closely as possible. Variations in the standard algal assay procedure included media variation with the use of an indigenous algal genus isolated from Lake Powell. The growth of the indigenous algal genus (Scenedesmus)was stimulated by adding oil shale extract at lower concentrations. Higher concentrations of oil shale leachate inhibited the indigenous algal growth.
only boron has been reported in quantities that are toxic to plant growth (6).Also, the presence of trace organic materials which are known carcinogens has been established (7). Entrance of complex mixtures from the waste materials into water systems may lead to bioaccumulation of some of the mixture components. In addition to bioaccumulation, other hazards or successional changes may occur a t critical tolerance levels to key terrestrial and aquatic biota. In order to predict changes in the biota, these critical tolerance levels and other environmental effects of ground disposal of shale oil wastes must be delineated (8,9). The effects of dissolved solids on phytoplankton have been studied in the lower ranges of salinity concentration in order to delineate maintenance media for freshwater phytoplankton. However, little work has been done on the effects of increased salt concentration on these freshwater organisms. A general literature review of suspended and dissolved solids effects on freshwater biota was conducted by Sorensen et al. (IO) and few studies of phytoplankton were mentioned. Specht (11) reports inhibition of Selenastrum a t salinities greater than 9%. In the Sea of Galilee, enrichment of water samples with an inorganic salt medium caused radical changes in the algal composition of the enriched samples. The appearance of a Chrysophycean flagellate, Prymnesium paruum, in the enriched samples caused concern because this alga is known to cause toxic blooms (12). Gupta (13) discussed the ability of blue-green algae to tolerate high levels of salinity, but it was usually assumed that something other than salinity controls algal growth (14). Some algae can use organics as a growth substrate, and organic fractions of domestic sewage have been found to stimulate algal growth (16).Also, vitamin requirements have been shown for many algal species (15). Trace metals present in oil shale leachate can change the community composition of the phytoplankton. In Patrick’s (17 ) study of the effects of trace metal pollution on diatom communities, she suggested that the presence of minor trace metal pollution may cause a shift in the diatom genera. In the presence of larger amounts of trace metal pollution the diatom community may be replaced by forms of green and blue-green algae. These algae tend to be more tolerant of trace metal contamination than are the diatoms. However, boron, which is abundant in some spent oil shale ( 6 ) ,has been identified as a possible requirement for diatom growth (18).Meyer (19) discussed changes in algal populations that correlate with trace metals concentrations in a reservoir. These included cyanophytes as well as diatoms. I t is difficult to generalize about trace metal toxicity since it has been found to be both species and temperature dependent (20).
and incubated under identical physical conditions. Control flasks of the test alga and medium were cultured along with the various treatment flasks. These included the same test alga and medium, with the addition of whatever was being tested. The effect of the treatment on algal growth was determined by comparing the treated flasks to the controls. Modifications to the standard algal assay procedure (21) were made using the general guidelines presented in Standard Methods (22). Algal Isolation a n d C u l t u r e Maintenance. The alga, Scenedesmus bijuga, was isolated from samples collected by Water and Power Resources Service personnel, under the supervision of E. G. Bywater, at the Wahweap station on Lake Powell. This green alga is abundant in Lake Powell (24).This alga was isolated and maintained in Lake Powell synthetic medium (TDS = 780 mg/L), which is algal assay medium (AAM) (21) modified by the addition of the major cations and anions measured in Lake Powell (25).Unialgal cultures of the test alga (hereafter referred to as Scenedesmus) were maintained via standard algal assay procedures except for the media modification already described. Regular Bioassay Monitoring Techniques. The bioassay flasks were monitored daily for the first 5 days of the bioassay and every other day after the period until growth ceased. Algal growth was estimated as a function of two different variables: chlorophyll a and optical density of the cultures. Chlorophyll a measurements were made using a Turner Model 430 spectrofluorometer operated a t a band width of 60 nm for both excitation and emission wavelengths of 440 and 670 nm, respectively. Two auxiliary emission filters were used to block the emission interference, a standard polarizing filter and a Corning No. 2A (Turner No. 110-816) glass filter. Optical density measurements were made using a Bausch and Lomb Spectronic 70 at 750 nm. Chemical Analyses. The chemical analyses of the major metals (Na+, K+, Mg2+, Ca2+, B3+, C1-, HCOJ-, S042-, Cos2-) performed on the oil shale leachates during the project all followed methods as described in Standard Methods (22). Flameless atomic absorption metal analyses were conducted using methods described by the EPA (23).The potentiometric method used for measuring the total alkalinity of the samples had to be modified due to interference in the test from the high total dissolved solids concentrations of the samples. This modification was the creation of a breakpoint curve for the samples to correct for the precipitation of low solubility compounds present in the samples. This modification is described in Standard Methods (22). Oil Shale Extraction Procedures. Both raw and processed oil shales were extracted via a technique (Figure 1) utilized by the Corps of Engineers for analysis of dredged samples (26). Processed Utah oil shale was also leached in an up-flow column (Figure 2). An up-flow rather than a down-flow column was used to avoid short circuiting of the water through the shale. This is a modification of the technique used by Maase et al. (27),using gravity flow instead of a pump to force the fluid through the bed of processed oil shale. The shale was air-dried to a moisture content of approximately 2% and then
Experimental The potential effects of oil shale leachate on phytoplankton productivity were evaluated using an algal assay procedure. In general, algal assays consist of measuring the growth of a test alga in separate 500-mL Erlenmeyer flasks. Each flask is inoculated with an equal amount of cells in 100 mL of media 684
Environmental Science & Technology
50 m l of o i l shale in a 500 m l Erlenmeyer flask
Add 200 m l o f
distilled water
Into constant temperature r @ @ m a t 2 4 O C f 2' and constant l i g h t a t 4 3 0 0 lux 2 10%
E x t r a c t on s h a k e r f o r 30 minutes a t 1500 rpm
Figure 1. Oil shale elutriation technique (26)
Table 1. Oil Shale Identification Listinga AR = raw Utah shale BR = raw Union shale AP = Paraho processed Utah shale BP = Union processed shale a These samples of oil shale were provided by the companies for analysis. These are all unhistoried samples from prototype operations and as such may not be representative of samples from a full-scale operation.
the water would percolate by gravity flow through spent shale disposal piles (2). Leachate and elutriate samples were collected and filtered through 0.45-pm Millipore filters (Type HA) and placed in sterile containers in the dark under refrigeration until used. The oil shale used for the elutriation and leachate procedures is identified by an alphabetic code. The legend for this code (Table I) states that these are unhistoried samples from prototype processes and therefore may not be representative of a full-scale operation. Each of the elutriates and leachates was subjected to the chemical analyses previously described. The salt composition of the extractions, as determined by analysis, was then used to prepare the salt additions used in the bioassay. These salt additions, composed of reagent grade salts and distilled water, were mixed to equal the salt composition of each elutriate and leachate. The elutriates, leachate, and salt additions were then tested a t four different concentrations of additions: 5,10,15, and 20% by volume. Data and Statistical Analyses. The algal biomass data were used to determine the maximum specific growth rate (hb) and the day it occurrkd. The maximum value of the growth rate for each treatment was calculated by the formula (21): hb =
RESERVaR
WASTE
In ( X 2 I X d
t2 - t l where Xp = biomass a t time = t2 and X 1 = biomass a t time = t l . The maximum standing crop ( X )of each treatment and
DISTILLED
the day on which it occurred were determined as the biomass achieved when the increase in biomass was less than 5%/day. These parameters were used for statistical analyses by conducting Duncan's multiple range tests on the data (28). Pearsall ion balances (Na K/mg plus Ca in mg/L and mequiv/L) were calculated for each of the oil shale elutriates and salt spikes.
4
+
DIAMETER INNER
MAMETER 114 INCH
+
LEACHATE
CLOSED ALL GLASS SYSTEM WITH TEFLDN
CONNECTIONS AND VALVES
Figure 2. The up-flow column for leaching oil shale (27)
2500 g of the shale was placed in the column without compaction. A sieve analysis showed the processed Utah shale to have an effective size of 0.098 mm and a uniformity coefficient of 5.63 mm. The flow of distilled water through the column varied slightly above 1 L per day. This is equivalent to a velocity in the column of approximately 3 x cm/s. This velocity was chosen as being approximately the velocity that
Results and Discussion Evaluation of Elutriates and Leachates of Oil Shales. Chemical Evaluations. The cations and anions prevalent in previous spent oil shale analyses in the literature were also prevalent in the analyses of AP shale which was leached in the up-flow column (Table 11).These analyses are grouped with the elapsed time a t which the leachate was collected from the column. The analysis period extended over day 1to day 12. The total concentration of the ions and the p H of the leachate decreased steadily. Throughout this time period anion concentrations (mequiv/L) remained in the same order of dominance: SO4 > HC03 > C1. The relative abundance of the cations with the exception of potassium shifted during the analysis period as follows: day 1, S a > Mg > Ca > K; day 2, S a > Ca > Mg > K;day3, C a > Mg > S a > K;day 5, Ca > Na > Mg > K; days 9 and 12, Ca > Mg > Na > K. The cation and anion data were also normalized to the last analysis day to facilitate comparison of the relative abundance of these ions over the analysis period. Trace metals concentrations (pg/L) occurred in the following order of abundance: Ba > Zn > Fe > Mn > Cu > Ag > P b > Se. The chemical analyses of the elutriates for all the shales studied are summarized in Table 111. For each of the shale Volume 14, Number 6, June 1980
685
Table II. Summary Table for the Characterization of Oil Shale Leachates AP
~leachate 1 mglL mequivlL
*
leachate 2 mglL rnequivlL
leachate 3 mg/L rnequivlL
leachate 4 mglL mequivlL
leachate 5 mg/L rnequivlL
leachate 6 mg/L mequivlL
elapsed sampling time h
z 1 Na 2 Mg 1K 2 Ca
42 1.75
30 1.25
days cations 2704.0 317.1 454.98 465.5
117.6 26.08 11.64 23.23
1990.8 176.6 159.7 534.9
2178.6
78 3.25
86.60 14.53 4.083 26.69
438.6 226.8 357.1 501 5
2131.9
2
127 5.29
19.08 21.95 9.134 25.02 75.18
183.2 88.47 72.0 573.3
006 57 78 8610 0
30 1800 1634 0
7.971 7.280 1.84 28.61 2 45.70
223 9.29
35.57 45.09 12.62 309.71
1.550 3.709 0.323 15.46
295 12.3
21.87 24.10 8.28 172.06
221.037
0.95 1.98 0.212 8.566
211.731
anions L
1 CI 2 so4 1 HC03 2 C03
ion balance, YO trace metals, pg/L Se As
Fe Ba Pb
Mn
cu Zn Cd Cr
Ag
2.0 6600.0 1483 0
0.06 137.4 23.31 0
20 5250 1156 0
006 1093 1894 0
20 2775 5254 0
2161.8
2m
2&5G
4.93
2 77
12 3
0095 3748 2680 0
1175 9668 1330 0
212 6
0.033 20.13 2.180 0
B
222.34
z12.461
3.00
3.02
139.0
alkalinity,mg/L as CaC03 total dissolved solids, mg/L specific conductivity, pR-’/cm Pearsall ion balance
0.043 10.04 2.378 0
2.2 BP elutriate. The growth of Scenedesmus was less in the BP shale elutriate than the growth in the raw shale (Figure 4). The addition of many of the spent oil shale elutriates and leachates stimulated the growth of Scenedesmus. Concentration effects of these additions did not provide consistent conclusions. Extracts from the AP shale stimulated growth
11.3 0.234 8.33
7.38 0.523 9.04 121 155 1.697
0.153 0.523 8.85
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more than the extracts from the BP shale. Therefore, growth stimulation of Scenedesmus is dependent on the source of the shale and the process applied to the shale (Table IV). In general the extracts from the spent shales stimulated growth more than did the extracts from the raw shales. The processing of the shale appears to make growth stimulating compounds more available to Scenedesmus. These compounds may be low molecular weight aromatic hydrocarbons, which were found to stimulate algal growth in other petroleum Volume 14, Number 6, June 1980
687
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products (29). The spent shales did stimulate growth as compared to their matching salt controls. Therefore, this stimulation was not caused by the addition of any of the salt compounds. This differed from the comparison of the growth of raw shale extracts to their matching salt controls. The growth of the raw shale extracts was less than the growth of the salt controls. This would suggest toxicity or a decrease in the limiting nutrient availability from a component of the oil shale extract other than the salt component. Linear correlations were made between the biomass and the trace metals present in the extracts, but no consistent correlations could be found between the Scenedesmus biomass data and the trace metal concentration in the extracts. Generally, the concentrations were lower than the toxic level to algae, and because of this the growth depression was probably not due to the trace metals present in the extracts. The electrical conductivity of the culture media did decrease significantly during the bioassay with Scenedesmus. An example of this is shown in Figure 5, a linear regression on the electrical conductivity data vs. time for the bioassay flask treated with AP leachate. Comparison of the Salt Effects to the Oil Shale Elutriate Effects on the Productivity of Scenedesmus. The effects of oil shale elutriates were compared to the salt effects by comparing the growth of the controls to the growth of the extract additions; controls were AAM plus salts equivalent to the salinity of the extract (determined by analysis). The raw shales both showed better growth responses than their matching salt controls (Table IV). The spent shales produced the opposite effect with the spent shale showing less growth than the matching salt controls. This effect of the spent shale and matching salt control is shown in Figure 6. Significant differences ( P < 0.05) in growth rate measured by fluorescence occurred, although no significant difference in was found from the Duncan's test. Pearsall ion balances of the salt spikes and the oi1:hale elutriates were evaluated for linear regression with the A ' and &j for each concentration of additions. No correlation could be found between these variables. Leachate and Elutriate Procedures. The leachate did provide the additional knowledge that the composition of the major cations changed in order of dominance over the extraction period and the pH decreased steadily during the extraction period. Therefore, the ion composition and pH of the leachate from the spent oil shale disposal sites may change depending on the age of the disposal site shale being leached with water. Both of these variables affect the biostimuldtory or toxic responses of phytoplankton and so the age of the
1 16
(DAYS)
Figure 5. Decrease in the electrical conductivity of the culture medium plus AP leachate (20 mL) in the presence of Scenedesmus growth
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disposal site shale could change the phytoplankton response to the leachate. The water passing through a spent shale disposal pile will be moving at all times. The contact times of the water and shale will vary, but the water will be recycled. This would suggest a higher concentration of oil shale components in this disposal water. Problems in the utilization of the Corps of Engineers standard elutriation procedure occurred. The elutriation procedure did not totally wet the interior of the most hydrophobic shales. The standard elutriation procedure was obtained from standard soil analysis and designed for testing samples from dredged sites. Thus it may not be appropriate for elutriating shales. The hydrophobic nature of some of the shales did preclude complete extraction using this technique. The leachate procedure did wet the shale in the column. This may be due to the 1.5-ft (46 cm) head used to push the water through the column. Application of the Bioassay Results to the Colorado River System. Algal assays are a biological tool for assessing the effects of specific chemicals in aquatic systems. Specific growth parameters have been observed to respond to the set of chemical variables that constitute a water sample. Thus, the bioassay serves to conveniently and inexpensively integrate the effects of biostimulatory and toxic chemicals, some of which may not be defined or difficult to evaluate in combination with other factors. The bioassay has no direct ecological application but can be useful to predict impacts of certain management decisions. Volume
14,
Number 6, June 1980
689
The literature (13) suggests that an increase in salt concentrations would provide a competitive advantage for cyanophytes. Therefore, salt inputs from the development of oil shale could provide a competitive advantage for blue-green algae. The increased presence of cyanophytes would represent a change of species composition of Lake Powell. At present no cyanophytes are common in Lake Powell. Also, it is suggested in the literature review ( 1 0 ) that lower Pearsall ion ratios (
