ML19210B857

Biological Survey of Susquehanna River in Vicinity of York Haven,PA,1969 Progress Rept, Prepared for PA Power & Light Co & Met Ed

ML19210B857
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Site:	Crane
Issue date:	03/10/1970
From:	Wurtz C LA SALLE COLLEGE, PHILADELPHIA, PA
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ML19210B855	List: ML19210B854 ML19210B856 ML19210B857
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{{#Wiki_filter:- A BIOLOGICAL SURVEI C? THE SUSQUDIANNA ?.IVER IN THE VICINITY OF YCRK HAVEI, PA. 1969 PROGRESS RE?CRT prepared for PEINSYLVANIA PCWER & LIGHT COMPANY and ETRCPCLITAN EDISCN COMPAh"? 07 Charles B. Wurtz Consulting Biologist La Salle College Philadelphia, Pa. sub:::itted 10 March 1970 7911120W c :: p 1,i 4 a/J i

CONCLUSIONS 1. The Susquehanna River in the vicinity of York Haven Das has been subjected to biological depression for three successive years as neasured by the species diversity of the resident fauna. The fauna of =acroinvertebrates sarpled included 145 species in 1967, 119 species in 1968, and 79 species in 1969. 2. The 1969 collections show relatively low variance a=cng the eight stations studied, and this reflects sinilar ecological conditions eng the stations. 3. There are strong indications that a toxicant has been introduced into the river frem above the study area. The tcxi-cant appears to be incipiently persistent or regularly recurrent. 4. The causative agent of the biological depression is core pronounced above the York Haven Da= than below it. This is reflected in the high coefficient of correlatien values found above the das in 1969. 5 The discharge from the Brunner Island Plant appears to have a retarding effect en river biology as far downstream as Station 3, but not as far dcwnstream as Station 9. };,J ,iJ l " 1

~ A BIOIfGICAL SIRVEY CF TE SUSQUEHANNA RIV2R IN THE VICINITY OF YCRK HAVEN, PA. 1969 FROGRESS REFCRT INTRODUCTICN This surrey was the third biological survey undertaken in the interests of the Pennsylvania Power & Light Co=pany and the Metropolitan Edison Company. The survey represents a study of the macroinvertebrate fauna (bottom organisms) at each of a series of eight stations. The field work was done from August 4 through August 8, 1969. STATICNS The location of each of the eight stations sampled is in-dicated on Figure 1 of the first progress report submitted August 9, 1968. The stations collected are listed below. Station.1. This station was in the riffle area above Threemile Island and between the head of Fall Island and the eastern shoreline of the river. Station 2. This station was between the northern tips of Threemile Island and Shelley Island to the west of Threemile Island. I ) e ~ Station 3 This station extended frem the southern tip of Shelley Island to the western shore of ThreeM 'e Island at the " Bali Lai" summer cottage. Station 4. This station extended from the southern tip of Shelley Island to the southern tip of the next island west of Shelley Island. Station 5 Deleted from the survey after the 1968 study. Station 6. This station was located along the western shore of the river above the mouth of the Conewago Creek di-version channel that skirts the northern edge of the Brunner Island Plant site. Station 7 This station was located between the northern tip of Haldeman Island (=Elliot Island) and the eastern shore. Station 8. This station was located along the western shore of the river about one mile below the d,ischarge canal of the Brunner Island Plant. Station 9. This station was located at the western edge of Haldeman Riffle above the mouth of Codorus Creek. WATER QUALITY Cn August 7, 1969, one set of water samples was taken for water quality analyses. These analyses were performed by the laboratory personnel of the Pennsylvania Power & Light Compary. 1 n, n \\\\7 s u

Results of these analyses, expressed as parts per million, are presented in Table 1. TABIS 1 Water Quality Characteristics Station Methyl orange Total Chlorides Alkalinity Hardness (as NaC1) Suspended (asCaCO) (asCaCO) Matter 3 3 1. 22.0 96.0 15.0 37.0 2. 14.0 106.0 15.0 39 5 3 17 0 98.0 15 0 32.2 4. 22.0 84.0 13.0 13.2 6. 61.0 102.0 16.0 26.2 7 19.0 108.0 17.0 L2.2 8. 60.0 101.0 17.0 L2 5 9. 56.0 93 0 16.0 29 9 Table 2 presents the average value for each of the water quality characteristics of Table 1 for each of the three years of study. Results are expressed as parts per million. TAELE 2 Average Water Quality Year Methyl orange Total Chlorides Suspended Alkalinity Hardness (asNaCl) Matter (asCaCO) (as CACO ) 3 3 1967 43 9 104.9 13 8 15.2 1968 58.1 180.1 24.2 12.a 1969 33 9 98.5 15.5 32.8.o i j

The variation in water quality from year to year reflects the variatien in runoff preceding the time of sa=pling. Average river flow during the twelve days preceding each of the annual surveys were as follcws: 1967, 19,590 ers; 1968, 7,490 efs; 1969, 30,991 cfs. With increased discharge the methyl orange alkalinity, total hardness, and chlorides are diluted. At the same time. scouring increases the load of suspended matter in the water. From the data presented it is apparent that the resident fauna of the river is adapted to wide fluctuations in water quality. BIOLOGICAL CCLLECTIONS A total of 79 species of macroinvertebrates was collected during the 1969 survey. The corresponding collections for 1967 and 1968 respectively were 145 species and 119 species. It is apparent that the river has been sufferidg f:om a biological decline since the investigatiens began. The species collected in 1%9 are listed in Appendix A along with their distributien a=cng the eight stations. Table 3 summarizes the collections frca the three years of study. _a_ \\E10 I, i 3 siv e

TAELE 3 Numbers of Macroinvertebrate Species Station Non-insects Insects All Species '67 '68 '69 '67 '68 '69 '67 '68 '69 1 20 23 12 23 31 22 43 5A 34 2 18 20 5 28 22 24 46 42 29 3 19 15 8 16 12 8 35 27 16 4 20 13 5 28 13 8 A8 26 13 6 12 14 6 44 24 26 56 38 32 7 13 10 7 32 29 22 A5 39 29 8 7 3 A 32 7 11 39 10 15 57 35 22 70 54 26 9 13 19 A Fcur dominant species (5% of the total) are recognized herein. The first of these is the bryczoan, Plumatella repens, the second is the snail, Physa heterostrcpha, and the third and fourth are midge larvae, Ablabesmyia mallechi and Polypedilum 1111ncense. Dcminant species in 1%7 represented 6% of the total collected, and, in 1968, 5%. Of the 79 species collected in 1969, 39 (k9%) were unique in the sense that they were cellected at only one of the eight stations. In 1967 there were 53 (37A) unique species; in 1968 there were 52 (44%) unique species. The 1968 collections of H9 species represented a loss of

19) of the species from the 145 species collected in 1967 The 1969 collections represented a drcp of 45 5% frem the 1967 species diversity and a drop of 33.6% from the 1968 species diversity.

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It is of importance to note that many of the species records presented in Appencix A are represented by single specimens. With sc=e species, notably larger animals, aggressive predators, or rare foms, this is not unusual. However, in the 1969 collec-tiens seme groups were severely reduced in numbers. Some forms that represent an unnaturally low frequency of occurrence are mentioned below. The snails Campelema integru:2.and Nitocris carinatus were represented by single specimens. Usually these snails occur commonly in those habitats suited to them. The scud Hyalella azteca is usually abundant within a suitable habitat. In 1969 a single specimen was taken at Station 1. The dragenflies, which are generally very hardy crganisms, were represented by a singla. specimen from Station 8. The caddisflies, usna11y ec= mon when they are in a suitable habitat, were also represented by a single specimen (frcm Station 1). The same condition prevailed for the large water strider, Gerris sp.1, which was taken at Statien 7 With the exception of the midge larvae, only one fly larva was collected. This was a specimen of a cranefly (Tipulidae). Other species were also represented by single specimens, but, as mentioned above, this is not necessarily unusual. At the same time, if " single-specimen" species were deleted frem Appendix A the total number of species reported for 1969 would be reduced ROD ) *" \\ s/u

from 79 to 57 (If " single-specimen" species were deleted frem the 1967 and 1968 collections the numbers of species reported in the progress reports covering those surveys would also be reduced. However, the reductions would not be of the same magnitude as occurs with the 1969 collections.) Table 4 indicates the number of species found at each station in 1969 if " single-specimen" species are deleted. TAELE 4 Species Represented by Multiple Specimens Station Species 1 29 2 25 3 14 4 12 6 27 7 27 8 13 9 24 The basic descriptive statistics developed from the biological data include the mean (i), standard deviation (s), variance (s ), and the coefficient of variation (V). Table 5 presents these de:criptive statistics for each of the three years of study. IJ/v iL-t

L. TAEIZ 5 Descriptive Statistics it s s V 1967 Non-insects 15 A.72 22.29 315% Insects 33 12 75 162.57 38.6% Total Species 48 10.93 119.k3 22.8% 1968 Non-insects 15 6.31 39.86 L2.1% Insects 22 10.05 101.29 A5.7% Total Species 36 14.89 222.00 41.4% 1969 Non-insects 6 2 70 7.29 h5.0% Insects 18 7 72 59 57 L2.% Total Species 24 8 31 69.14 34.6% It is apparent from the data of Table 3 and the statistics of Table 5 that the Susquehanna River differed widely in its biological structure during the three years of study. During the three years of study the river has suffered centinuing attrition in species diversity. To the extent that the coeffi-cient of variation reflects increasing stability with lowering values it would appear that the river passed through a period of degradation before the 1968 collections were made, but that this has stabilised at a new, lower level of species diversity. This could be interpreted as meaning that whatever the cause of the degradation it is now incorporated into the envirennent as a constant, or regularly recurring, factor. Whatever the cause, it extends throughcut the entire geographic area studied. r q n, J< E 4_ )

A chi square analysis comparing the 1967 and 1968 collec-tions produced a chi square value of 19.93 This represented a statistically significant difference with p=0.005-0.010. A chi square analysis ec= paring the 1968 and 1969 collections produced a chi square value of 8.16. This is not statistically significant (p=0.250-0 500). This would tend to support the opinion that the river's biological structure has ccme into equilibrium at a lower level'of species diversity. Using rank order correlation the 1967 collections when ec= pared with the 1968 collections had a rho value of 0 375, which is not significant. The sane analysis applied to the 1968 and 1969 collections produced a rho value of 0.71A, which is significant at the 5% level. Once again, this tends to support the opinion that the river was ina\\ transitional stage toward biological depression in 1968, and that in 1969 this had stabili::ed at a lower level of species diversity. Ccmparisons have been made between the group of four stations (1-4) above the York Haven Dam and the group of four stations (b9) below the da=. 31967 no significant difference was found between these two groups (chi square value was 2.26 with p=0 5CO-0.750). In 1968 a significant difference between the two groups was fcund (chi square value was 20 30 with p= 0.005). _9_ ,rnq 4 b f

In 1969 conditions reverted to the 1967 situation with no significant difference found between these two groups of stations (chi square value was 3.39 with p=0.250-0.500). As suggested in the 1968 pr05ress report, this appears to be a corollary of streas flow. During both 1967 and 1969 river discharge was high enongh to be sp4'"ng from the York Haven Das pool by way of the spillway. During 1968 the river discharge was so low that the river below the das received only that water which ca e through the hydro plant. Flows as low as this would severely linit the transport and distribution of bottom organis=s. Further discussion of the influence of flow conditions was presented in the 1968 progress report subcitted 24 Jarza.ary 1970. The descriptive statistics for the above-da: and below-dan faunal groups are presented in Table 6. TASIE 6 Descriptive Statistics Above Das 2 2 s s V 1967 Non-insects 19 1.C0 1.00 0.05% Insects 2h 5.63 32.53 23.7% All Species L3 5.71 52.66 13 3% 1963 Non-inse cts 18 L.53 21.00 25.1% Insects 20 S.91 79 33 L4.6% All Species 37 13.35 172 33 36.1% r-n lb/J lJ _ 10

4 ~ TABLE 6, cent'd. 2 s s y 1969 Non-insects 8 3.37 11.33 A2.1% Insects 16 8.72 76.00 54.5% All Species 23 10.10 102.00 43.9% Below Das 1967 Non-insects 11 2.88 8 33 26.2% Insects 41 11.80 139 33 28.2% All Species 56 14.21 202.00 25.4% 1968 Non-Insects 12 6.97 A8.67 58.1% Insects 24 12.04 145.00 50.25 All Species 35 18.36 337.00 52.5% 1969 Non-insects 5 1.53 2 33 30.6% Insects 20 6.32 40.00 31.6% All Species 26 7.44 55.33 28.6% As stated in the 1968 progress re;crt, the biological structure of the river as found in 1968 reflected a loss of biological stability frcs the conditiens of 1967 and the fauna was apparently in a state of fhx. By 1969 a considerable de-gree of stability had returned to the river as reflected by the reduced variance (s2). Bis is even nere evident below the York Haven Da= where the coefficient of va.dation (V) has re-turned to levels cenparable to those found in 1967 He pool above the das has not yet achieved this degree of stability. Bis indicates that the influencing factor has its crigins above the study area. * ' )

During the 1968 field work dead unionid cla=s were observed at Statior.4. Death had been so recent that nuscle tissue was still adhering to the inside of the shells. S4 d ' ar cbse_7a-tions were nade in 1969 A dead clan (Anodonta cataracta) was found at Station 3 with adhering tissues. ~his indicates death within the preceding LS to 96 hours. In the headwaters of the York Haven Das two dead class (7"dptic ce=planata) were seen floating en August hth. Class float only when the soft parts of the ani=al have decc=posied to the point *.h.ere gases are g?nera-ted, but the tissues have not been totally destroyed. These ard is must have died within the preceding 2L to L8 hours. These observatiens indicate that sete toxicant is being introduced at low levels and the clam population is continuing to suffer attrition. Other species are also subject to death by this influence, but are not so readily apparent in the field. "he dead class observed would be several years old, so no nassive discharge of a toxicant has occurred. If a nassive discharge had occurred the total population would be annihilated at the same time. This has not happened. - 7 / I b

APPEfDIX A MACROINERTEBRATE SPECIES Stations FIATWORMS 1 2 3 i A 7 8 9 1. Dugesia Tigrina X WORMS 2. Li=nedrilus cf. hoff=eisteri X X X X 3 Branchiura sewerbyi X

4. :Lu=briculidae g. sp. 1 X

X ERTOZOA!G 5 Plu=atella repens X X X X X X X 6. Lophopodella carteri X CIAMS 7 Sphaeriu: sp. 1 X X X 8. Pisidium sp. 1 X SNAII.S 9. Ca pele=a integrum X

10. A=nicola ef. limosa X

11. Goniobasis virginica

'I

12. Nitocris carinatus X

13 Ferrissia ef. tarda X X X X X

14. Physa heterotropha X X X X X X X 15 Heliso=a anceps X

16. Ly=naea humilus X X X X X X

CRAYFISH 17 Orconectes sp.1 X X I SCUDS 18. Hyalella azteca X 19 Ga==arus fasciatus I X X X MA! FLIES

20. Stenone=a sp. 2 X

21. Stenone=a sp. 5 I

22. Tricorythedes sp. 6 X X X X 23 Leptohyphes sp. 1 X

24. Cloeon sp. 1 X

X 25 Baetinae g. sp. 1 I I X

26. Baetinae g. sp. 2 X

DRAGO!TELIES 27 Gc=phoides sp. 1 X ,r n '^^ / I b -t-

Stations DA'SEIELIES 1 2 3 4 6 7 8 9

28. Enallagma sp. 2 X

29. Enallag=a sp. 5 I

30. Enallag=a sp. 7 I

31. Ischnura sp. 1 X

32. Ischnura sp. 2 X X X

33 ef. Teleallag=a sp. 1 X

34. Hetaerina sp. 1 I

35 Early instcrs X X X X ' DATER STRIDEP.S AND ' DATER EUGS

36. Gerris sp. 1 I

37 L trobates sp. 1 I I

38. Trepobates sp. 1 I X X X X

39. Trepobates sp. 2 X

X X X

40. Trepobates sp. 4 X X

41. Rheumatobates sp. 1 X

42. Mesovelia ef. mulsanti X

X X X 43 Corixidae g. sp. 1 X X

44. Belostoma sp. 1 I X CADDISFLIES 45 Cheu=atopsyche sp. 1 I

LARVAL BEETLES

46. Elmidae g. sp. 1 I

47. Elmidae g. sp. 2 I I X

48. Elmidae g. sp. 3 X

49 Elmidas g. sp. 6 I

50. Elodes sp. 1 I

51. Hydrophilidae g. sp. 1 I

52. Hydrophilidae g. sp. 2 I

ADULT BEETLES 53 Hydrochus sp. 1 X X X X X

54. Stenelmis X

55 Fam. g. sp. 1 X

56. Fam, g. sp. 2 X

CRAIEFLIES

57. Tipulidae s. sp. 1 I

MIDGE IARVAE

58. Procladius sp. 1 I X X X X X 59 Conchapelopia sp. 1 I

60. Ablabes:::yia mallochi X X X X X X X

61. Ablabes::rra auriensis X X X X

X

62. Labrundinia virescens I

63 Cricotopus sp. 2 Roback X X X

64. Cricotopus bicinctus X

X 65 Cricotopus nr. trifasciatus X

66. Nanocladius sp. 1 X

X X - ii - r]J 1 ]OQ AV (/

Stations 1 2 3 4 6 7 8 9 67 Polypedilus illinoense X X X X X X X

68. Polypedilum sp. 1 X X X

69 Polypedilum halterale I I X X

70. Cryptochironomus fulvus X

I I

71. Cryptochironcmus blarina X

X X X

72. Parachironemus sp. 1 I

73 Dierotendipes nr. =edestus X X X X X

74. Dierotendipes sp. 1 X X X 75 Glyptotendipes lobiferus X

76. Chironemus sp. 1 X

X X X X 77 Chironemus sp. 2 X X X X

78. unidentified Chironemini X

79 Rheotanytarsus sp. 1 I X X a e J /V I * - 111 -

6 ' 4 4 6 Cz1 oHw C= <= H M N }i. N 4 I J /

SEC"ICN VI FUTURE ENVIRCNMENTAL PRCGRAMS Metropolitan Edisen Co:pany has retrained Dr. G. Ecyt Whipple as a consultant for the Enviren: ental Program for the Three Mile Island Nuclear Station. He has enlarged the secpe of the previous pr gran and with Metropolitan Edisen Cc=any personnel along with Dr. Donald Davis of Millersville State College is starting the following Phase Two environ-mental program for Metrcpolitan Edison Corpany. P9ASE *'40 Investigations have been started to identify pathways of potential significance by which radioactive caterials attributable to station opera-tion may enter hu=an fcod, to deter =ine what the concem, ration factors for isotepes of concern may be in these pathways and to establish practical ways for =enitcring the significant pathways. Work done to date indicates that river fish and = ilk are probably the cost significant food caterials of interest. Starting during the su er of 1970, measure =ents will be =ade of the ratios of stable element concentrations in river fish ec pared to river water to deter =ine cencentration factors in this pathway. The elements to be reasured will include these which =ay be present in significant arounts as radicactive isotcpes in plant liquid effluents (e.g., including signifi-cant ones listed in Table 7I-1). The concentration ratios reasured, alcng with other information, will be used as one basis for determining whether effluent discharge li=its will be affected by censideratien of human feed. ,--n t79 a,. d IJl

PHASE TEREE The pre-eperational radioactivity survey will begin about fifteen to eighteen =cnths prior to criticality and will end when criticality is achieved. It will include a period of about six to twelve =cnths during which sample locations and ceasurement intervals and techniques will be the same as proposed for Phase k, the operational survey. The purposes of this phase will be (1) to train personnel, (2) insure proper equip- =ent operation, (3) to verify that the sample locaticns chosen are suita-ble and that internally consistent data can be obtained, and (L) to obtain an indication as to measure =ent sensitivity and statistical variation of background radiatica levels. PHASE FOUR The operational survey will be a continuation of the measurements =ade in the Phase 3 pre-operatienal survey and will co= ence at the date when criticality is achieved. The prin ciple guiding the selection of sa=ple station locations is that for each type of sa=ple, reasurements will be =ade at both indicator stations and background stations. The indicator stations are to be located where the average concentratien of water borne or air-borne radioactivity discharged from the plant is esti=ated to be near a =ayd-"- in the enviren- =ent. The background statiens will be placed where such concentrations of radioactivity in the environment are esti=ated to be less than One percent of that at correspending indicator stations. Thus, if radicactivity attributable to the plant can be =easured in the environment, it should be detected by indicator stations. The background stations will provide con-current background radiation reasurecents with which the indicator staticn reasurements can be corrected. I D } 'i j Jio

The sa:pling interval and the type of reasurement made in Phase L will be adjusted depending on the amount of radioactive material released from the plant as deter =ined frem measurements =ade prior to release. If these releases reach a level greater than 1/10 the allowable leng-ter average release li=its established in the technical specifications (expressed, for exarple, as LCi/cc in water er Ci/see in air), the envirennental network will be operated in the cost intensive regime, Regime III. If the long-ter average releases are in the range of 1/30 to 1/10 of these li=its, the network will be cperated in Regime II. If they are less than 1/30 of limits, it will opeate in Regime I. The rules for changing frc ene regime to another outlined above are predicated on the assu=ption that release limits will be consonant with those derivable from the numerical limits specified in LOCFR Part 20. The typical indicater and background stations and typical sa=ple types and seasurement intervals assceiated with each regime are indicated in Table 7I-2. Preliminary locations for sa=pling will be established in the su==sr of 1970 and will be finally selected six to twelve conths before Phase a co==ences. If methods beco=e available for obtaining reproducable measure =ents of radicactivity, sedice:t sa:ples will be added to the list in Table VI-2. For the first year after criticality, in order to : y to measure radiation attributable to the plant, the survey will te conducted in Regime III no matter what the plant releases turn sut to be and even if esti=ates indicate levels in the environment L e too lcw to be reasured. If no significant differences betwe*" indicater and background levels are observed during this period rad if calculatiens and pre-cperational reasure-ments indicate that no significant d4 ##a-a-aas should be observed, the survey will then be cperated under Regime I. It will continue under n 1 - ', \\ l L s g l' V e J f

A_ Regime I until plant discharges average significantly more than during the first year (e.g., by a factor of five). If this occurs, Regime III will be put into effect for another period, again to try to =easure plant effects. This process will be repeated each time average discharge rates are a significant factor above those during previous Regime III cpera-tiens until diffarences between indicater and background stations are observed. Such differences, if they are ever observed,.will provide a basis for confir=ing or changing esticates of cencentration factors in principle food pathways and/or in the relationship between atmospheric and liquid release rates and concentrations in environmental air and water. e m 4 ~ j l

TAELE VI - 1 Estimate of Annual Release of Radioactive Lioulds to the Plver Isotocic Breakdcun of Annual Quantities of Activity Released to Plver Annual Concentratien Release in Cooling. to Tower Effluent Fracticn River MFC of Isotcee uCi uCi/cc uCi/cc MFC )- 25 .2 ,g x i ! =l!l# llE!!!!!!!!!!$is!!E f,*[f [ h 1! i:E:

lli:n-e 2 x lo O.

x 5 13 9 3 i in

gg"x10

3.47xh-{4 2 [ -5 0.2 x 0.346 j ,1 5 5 0.333 x 10-8 33 x 10 4 x 10 j 0.620 x 10-7 0-12 Cs 136 x 9 x lo- -10 Cs 137 32 0.0

• O a

0,057 0*191

• 10 Ba 140 0.045 4 54 x 10-15 3[h-5 x_

9 0.151 x 10 10 {',47; x 10-1593 x 10-16 f } ]_-5 0.735 x 10,10 La 140 0.015 5 Ce 144 0,00 9 H 3 8.64 x 10 - 8.68 x 10-4 3 x 10-3 0.29 Note: (1) MPC value not listed in 10 CFR 20. Utilized mest censervative MPC value given in 10 CFR 20 for unlisted isotopes. Total Activity 'and Praction of MFC of Annual Release to Plver Annus1 Quantity Fraction of MFC Released T7ee of Activity uCi in Cooling Tower Effluent Mixed Fissien Products 48,400 0.000249* Tritium 8.64 x 10+9 0.29

• For the mixture of isotcpes, excluding tritium, considered above.

15;0 136

Ts51e VI-2 TIFICE SCHEDULE FOR POST-OPE?ATICNAL FIGIMES NUMBER OF REGIME Indicator Background 7 77 777 Statiens Stations Air 7 5 S-1 C-1 C-1 Precipitation 7 5 S-4 C-4 C-4 Radiation 30 10 F-4 F-4 F-4 Milk-4 2 G-4 G-1 Crops To be decided H-52 H-4 River Water 2 1 S-4 C-4 C-1 Columbia Intake 1 S-4 C-4 C-1 Cla=s or Snails 2 1 G-13 G-4 Fish 1 1 G-4 Key: S-1 (S-4): collect centinuously for 1 week (4 weeks) and discard without analysis C-1 (C-4): collect continuously for 1 week (4 weeks) and analy::e F-4: film badge, or TLD exposed for 4 weeks and read G-1;(G-4): grab sample taken at 1 week (4 week) interval and analyzed G-13: a grab sample taken 3 times a year (spring, su==er, fall) at apprcximately 13 week intervals, and analyzed H-52: ene grab sample taken at harvest and analyzed H-4: one grab sample every four weeks during the growing seascn; analyzed 7 4 ,r - q J/J lJ/}}