Rortk Carolina Agricultural Experiment Station Sclenees Project No

OVERLAND FLOW PRETREATMENT OF \dASl EIJATEK

Rortk Carolina Agricultural Experiment Station and Life Sclenees Raleigh, North Ca

Project No. B-067-NC Agreement Na. 1 -31 -009%-41 13 June 1976

TABLE OF CONfENTS (continued) Page

LIST OF REFERENCES ...... 79 APPENDICES ...... 83 GLOSSARY ...... 138 RESULTANT PUBLICATIONS ...... 140 LIST OF FIGURES Page

1. Environmental low Sheet for Production Process...... 2 2. Economic Balance for Wastewater Pretreatment Process and Land Application...... 4 3. Land koa n GP? &eria for '>

7I 4, Biochemic

jl 5. Dimensions ...... , 0 30 .s*or*.*..

oadi ng Parameters : ...... 32 aste Loading ...... 3 3 tewater, OLFi ... 34 nd Wastewater ems ...... 34. stewater Based on ations Within ...*...... 35 ting Rainfall rsheds .-..... 6.1 the Thornthwai te Method...... 42 14. Volumetric Water Ma e (To~alfor Study Period) for Poultry Manure Slur s~~~...... 42 15. Water Mass Balance ash in OLF System for Poultry Manure ...... 43 16. Nitrogen Mass Balance Slurries...... 44. LIST OF TABLES (continued) Page 18. Comparison of Percent Concentration Reduction Relative to Time During Sampling Event - OLF of Poultry Manure ...... 9 19. Percent TKN Concentration Reduction: Mean and Standard Deviation - QLF of Poultry Manure ...... 20. Percent MM3-N Concentration Reduction: Mean and Standard Devia- tion - OLF of Poultry Manure ...... 50 21. Percent OGN Concentration Reduction: Mean and Standard Devia- tion - OLF of Poultry Manure ...... 59 22. Generalized Change in Concentration Reduction from First to Last Part of OLF Study ...... 51 23. Comparison of Concentration Reduction Means Between OLF Terrace Systems Receiving Poultry Manure Sl urry ...... 5 5 24. Comparison of Concentration Reduction Means at Flow Distances Within an OLF Terrace System ...... ,. 5 7 25. Simple Statistics of Independent Variables for Poultry Manure OLF Study. ..a..m...... ,...... r;~ 26. Regression for TKNAVG Concentration Reduction through an OLF Pretreatment System of Poul try Manure Slurry ...... 6 7 27. Regression for NH3AVG Concentration Reduction through an OLF Pretreatment System of Poultry Manure Slurry ...... 6 ? 28. Regression for OGNAVG Concentration Reduction through an OLF Pr2treatment System of Pouf try Manure Sl urry ...... 63 29. Regression for OGNAVG Concentration Reduction for Last Half of OLF Study...... (7 6 30. NO3--N Concentration in OLF Runoff: Mean and Standard Deviatim . 69 31. Mean NO3-N Concentration in Soi 1-Water Beneath OLF Site (mg1.4) . . 70 32. Mean NO3-N Soil-Water Concentration Beneath OLF Terrace System with Time (mg/X) ...... 7 0 33. NO3-N in Grass Harvested from OLF Terraces Receiving Poultry Manure Slurry (ppm Dry Wt. ) ...... 7 1 34. Redox Readings with Depth of OLF Terraces Just Prior to Normal Wastewater AppB ication (Eh) ...... 7 3

1 LIST OF TABLES (continued)

35. Concentrati on-Based and Mass Removal s far OLF Pretreatment of Pou1 try Manure, Influent Specified in Table 9 ...... 7 4 36. OLF Area Requirements for Pretreatment Combinations Using in a 7 (-I Farm Scale (1 0,000 Birds) Waste Management Sys tern ...... I 'J SUMMARY

The research concerning overland flow (OLF) pretreatment of waste- waters was initiated with three objectives : (1) an assessment of establ ished treatment mechanisms and literature data to rank the potential uses of the OLF process for municipal , industrial , and agricultural wastes according to advantageous usage in the Southeast; (2) experimental research into nitrogen transformations occurring in 01-F for poultry manure; and (3) the scale-up appl ication of research and project results to a farm animal prodwct~on level, Results were projected to encourage further use of OLF pretreatment for municipal and agricultural wastes in North Carolina and the Southeast. With regard to municipal wastes, OLF was estimated to be most advantageous when used to replace secondary treatment followed by direct stream discharge or by advanced treatment, Benefits were also derived when OLF was used as secondary treatment prior to terminal 1 and application, The least justification for OLF usage was as a form of advanced treatment following conventional secondary treatment whether a water or land-based receiver was employed, Industrial or agricultural wastes with nitrogen or organics as the land-limiting constituents can be effectively treated with OEF systems. The OLF study of nitrogen transformations for poultry manure slurry indi- cated the largest N pathway was the unaccounted for losses which include ni trification-denitriff cation and ammonia volati 1 lzation (50-70 percent of i nf 1 uent N) . Grass uptake was 5-20 percent, and conversion to nitrate in the effluent liquid was 5-10 percent of the influent N, The smallest pathways (1-3 percent) were the soil-water percolation beyond 2,4 m depth and rajnfall runoff losses. Similar levels of total N losses were achieved for 1670 kgN/ha./yr and 2970 kgN/ha./yr; for hydraul ic loadings of 4 cmjweek and 7 -6 cm/week; and for rest periods of 22 hours and 46 hours. Nitrogen losses increased from 50- 65 percent after 15 m of flow to 70-80 percent after 30 m of flow distance, Increased rest periods and lower waste application rates favored larger nitrification potential.

Utilization of OLF for a farm scale animal waste system is consistent with the objective of minimizing the land area needed for waste disposal by reducing the manure nitpogen quantity. Based on a 10,000 bird module, OLF distances of either 15 m or 30 m, and land application of resultant OLF effluent, the total Sand area needed is 10-12.5 ha. and 7,5-10 ha., respectively. This is 30-50 percent of the system size for direct land application of the poultry manure. A system was evaluated containing a lagoon following OLF, lagoon water recycled to flush and transport the manure, and land applicat-ion of the total system contents four Times per year. The total land area was 5-6 ha. and 5-6.5 ha. for 15 m and 30 m OLF distance, respectively, This system yequires 20 percent of the land area for direct land application of poultry manure, Specific conclusions for each research objective are grouped SndividualSy and listed under the Conclusion Section, CONCLUSIONS Overl and Flow Pretreatment Overview - Municipal Wastes A. OLF systems have been used as secondary and advanced treatment processes for municipal wastes in whlch the terminal receiver of OLF effluent can be water or land based. B. OLF of primary treated waste yields an effluent in which the BODu is nearly equal to that from advanced treatment, nitrogen removal is 60-98 percent, and phosphorus levels are about 4 mg t-POL-P/R and BOD, < 20 mg/R, C, OLF of secondary treated effluent dfd not yleld a substantially higher quality effluent than the OLF effluent from primary treated waste; hence, the cost effectiveness of CLF for secondary effluent is less. D. OLF of primary treated municipal waste can be used %o reduce the nitrogen content ("30%) to the poSnt at which hydraulic factors limit the land application of OLF effluent. E. OLF of secondary treated municSpa1 waste is beneficial if substantial water losses occur, but research results are not currently avail able to document such water removal s, F. The use of ground-level waste water land application can be used to economic benefit by reducing the magnitude of aerosol control buffer zones. Overl and Flow Pretreatment Overview - Agricul tura7 and Industri al Wastes A. These wastes typically have high levels of organic and nitrogen compounds ; and thus , the subs tanti a1 pretreatment removal s of OLF systems are advantageous. Treatment levels suitable for stream discharge are not common with concentrated wastes; hence, land application or further treatment must be considered, The OLF behavior of salt constituents in agricul tural and industri a1 wastes is not we14 documented. Overall Removals of Waste Constituents During OLF Pretreatment of Poultry Man ure A. On a mass basis TKN, NH3-N, and 0-N reductions were 70 percent, 83 percent, and 58 percent, respectively, after 15 m of flow distance; and 90 percent, 95 percent, and 85 percent, respectively, after 30 m of flow. The NH3-N performance remained constant throughout the study while 0-N reductions decreased to the zero percent to 20 percent level, B. On a mass basis, H20, COD, TOC, t-PO4-P and C1 reductions were 45 percent, 82 percent, 75 percent, 65 percent, and 25 percent, respecttvely, after 15 rn of flow distance; and 70 percent, 93 ' percent, 90 percent, 85 percent, and 65 percent, respectively , after 30 m. C. Completely smooth terraces were not necessary fop OLF pretreatmen t as no concentsatl on reduction difference was determined for liquid in channeled areas and liquld in more dlffuse overland f 1OW areas, D. At least three months of operation is needed to approach OLF operation characterqstic sf l ong-term performance, IV. Ni trogen Trans formati ons and Control 1 ing Vwlables In general, the terrace system receiving the lower waste loadings (2.7 cm/week and 1100 kg N/ha,/yr) yielded significantly greater TKN removals than the more heavily loaded terrace system (2,6 - 5,0 cm/week ~nd1900 kg N/han/yr), The differences between terrace systems reflected In NH3-N and 0-N csncentratfsns were not as large as TKN when compared to standard data varfaba"1 ity,

A regression analysis for NH3-N concewt~al5onreduct%n no a gIven terrace revealed little consistent effect 0f duration of study, 1iquid residence tfme, ambient temperature, influent waste concentration, and the amount of antecedent rainfa1 %, The RQalue was 7 ow indicating that other untested variables weye control l ing. A siml" l as regresslola for 0-N cancentratlon reduction determined that the duratlon of the study and the influent waste concentration were signi ficant independent variables, The 0-N coneentra- tjon reductfon decreased as the length of the study increased and increased as the concentration of the input wastewater was Increased, The use of OLF to provide condit-ions favomble to nitrification of poul try manure was evaluated by various waste IoadSngs and per1 ods of drying--resting between wastewa%er appl fcation, The use of lower waste and hydraul lc app7 icatlons (1I00 kg MJha./yr and 2,7 cmlweek) and the use of extended pest periods (46 hours versus 22 hours) yielded greater nitrate levels in the ObF runoff liquid, These results were cormbomted by grass tissue nitrate concen tratlhs, The popul ati ons of ni tri fying or-ganisms , flizrobhcter and PJit~o- sorn~nm from 0-15 m of Plow dl stance were in the range of 1 x $0" - 1 x IOWPN as compared to 1 x 10" 1 x 103 WN for %he control adjacent land area, The lower loading terrace had ~ljghtlyhfgher organism levelsc After 25-30 m and 40-48 rn the levels had decreased to 5 x $03 - 1 x lo4 MPN and 1 x 10" 5 x lO"PN, respectively, Initial ly, the N<&mbacter popul atfons were larger but after IS weeks the ~~~&PQSDWL~~Spopulations became the larger, In the control slte the N.t~osomsr,aa levels were conssisteiiatly above those of Nitrobaceer. V. Farm Scale Usage sf OLF Pretreatment A. An OEF pretreatreatment process can be used to reduce the total land area requirements for anlmal manure by prswld%ng nftrsgen removal, Thf s objective is non-conservatory but cons? stent with the objectives of a substantial number of producers. B. The use of a flush manure system in the production unit followed by OLF and then application of OLF to a terminal land receiver results in a 50-70 percent reduction in total waste management 1 and area when compared to l and requirements for direct land appli - cation of poultry manure, C. Addition of a lagoon providing three months storage following the OLF process, with recycle of lagoon water for manure ftushing, results in a 75-80 percent reduction fn total waste management land area.

xiv RECOMMENDATIONS 1, The water loss attainable for OLF veysus the recommended spray application design should be compared on an annual basis for potentlal advantages in reducing hydraulic 1imi tat1 ons for 1and-based receiver sys terns, 2, For munici pal wastes data are needed on design criteria which produce improved pathogen dieoff and which can be used to more accurately predict those soi 1 properties which wi 11 pemi t satisfactory OLF performance. 3, A broader utilization of OLF with various agricultural and industrial wastes is needed to expand the performance data base and to assess the full potenti a1 of OLF pretreatment. 4. The relationship between wastewater application and rest periods as an anaerobic-aerobic cycle must be extended to establish the potentlal for n 1 trogen removal . 5. Extended animal waste experiments are needed to verify long-term system performance. Acknowledgements

The au'thors wish to record the steady, fundamental support of Water Resources Research Insti Lute Director, Dave He Howel 1s qnd Biological and Agricul t,uraJ Engineering Department head, F. J. Hassler, who have made 9 broad range of environmental research possible. Project field work was ably done by Flessrs. Jim Olson, Ken Swartzel, Tony Jacobs, Jim Merchant, Jimmy Pierce and Neil Ross. The laboratory effort was i nval uabl e and acknowledgements are i n order for June Preston, Bertha Crabtree, Dorothy DeBruyne, Mary Beth Wi 1 kie, Patty FlcBride and Judith Lynn Lou Adams.

The cooperation of Sly. Henry Marshal 1, Mr. J. R. Idi 11 jams and other members of the North Carol ina Agricultural Experiment Station was vital in the successful completion of this research. Support from the Poultry Science Department began early and sustained the project as it progressed. Editorial and typing responsi bi 1ities were performed we1 1 by Mrs. Peggy Price and Mrs. Thelma Utley . SECTION I

IMPLICATIONS OF OVERLAND FLOW FOR WASTE MANAGEMENT

The purpose of th=is Intr.aduction fs to deflne In overview what +% meant by pretreatment, to present the factors which must be considered 9t-i selectfng any of the many available pret~eatmentalternatives, and then to place overland flow technology in the perspec%lve of a pretreatment pr Inherent in the design of waste management systems as the differentiation between the source or generation of wastes, the terminal treatment or disposal system, and those intesmedlate unit processes, which alter the raw waste prior to the termfnral receiver, Figure 1, The Sntemedl"ate unl t ppocesses are defined as pretreatment uwts because (a) these units operate prior to some terminal seceiver system, (b) the use of these unl ts results -in reduction of some or a"% of the constituents in the raw waste load, and (c) such units alone o~ In combination are only a part of a total waste management system, Pretreat- mentcomplexity ranges from zero (pusnpdng only) to two or mope types of removal or conversion processes in series, In general , for the agrieul ture, municipali- ties, and certain ndustrial categories the teminal receiver systems are either 1 and-based or water-based; thus, pretreatment must be csnsidered sped fi cal ly in relation to each of these receivers,

liili thin a total waste management system, the method01 ogy for selecting or eval uatf ng pretreatment processes s important, The dominant justi fication for using pretreatment of a waste is to cause reduction in costs associated with the termjnali rece-iver whqch leads to an overall minfm"A^aatfon of the total system costs w%thin the envi ronmental regulatory const~aints, The major secondary justiff cation for a pretreatment process is to provfde management flexibility In the total system- However, Prom a quantitative viewpoint jt is difficult to translate th%sflexibility into cost savings; hence, the majority sf design and engineering deals wlth the primary cost savings, Prior to discussbn of the control l lng factors In selecting a pretreatment, certaln definitions are needed.

- Wate Constituent Gencr;zt;im Is the characteslzatlon sf a waste by the individual constftuents or family of compounds when put on a basis of mass per unlt of tlme and per unit of end product production; e,g,, kg niCssgen/d,/kg tomatoes processed, - Waste AssimiZacoq CqabiZit2 is the unlt rate, expressed as mass per unit tfme per volume or area of receiver by whfch a csnst=ituent or family of constituents are stab1 7 ized, separated, or converted 3 n an envi r~nmenlal%y acceptable manner" She important factor Is the papti cu%at- receiver chosen, ei they water-based OF 1 and-based; e,go, kg nii trogen in grass erptakelyeasl hectare of plant-so11 system,

- Lmd Limiting Cmstihen.P GLLCB' gar St~emLirniti3z.g Con@t

or more compounds must be considered as simultaneously Ilms'tlng e-ither jn the raw waste or in the wastewater after a percentage of the orlginal LLC has been removed,

The first consfderaclon +n selection of d prexseatrnent process Is to determine whether or not the unit process significantly reduces the LLC or SLC. There are numerous examples of treatment processes advocated for a pasticul ar waste which remove certafn constituents well, but the LLC remains constant. In terms of the total system costs such pretreaxmnt Is not effective, If a pretreatment process does reduce the LLC or SLC, then consfderation must be given to the cost per unft of constituent removed. This unit cast wi 17 usual ly not be constant but, rather, will increase as diffe-rent processes are consi as a greater percent of the LLC or SLC Is separated or reacted, FSgure 2, The pretreatment curve represents the cost a? (9 1 dl ffesent unit processes which must be employed to achieve the Yndicated percent* removal of limitlng constituent(~)or (2) a gl ven process which can be operated at several levels to achieve va~ioustreatment levels, Thus, an pmparing the pretreatment cost curve various alternatjves or perfomance levels must be estab7 $shed OQ the basis of removal of the I lmiting parameter, Addjtion of the land recejver costs and pretreatment cast perm1 ts the compara'son of several cornblnations of pretreatmen.i;- terminal recelver to be optimized for the least overall costs, Figure 2. The stepwl se process detalled above Is especial ly necessary when considering 1 and- based sys tems sf nce few existing pret~eatrnentprocesses have been ewal uated in respect to the LLCCs), and there are slgniflcantly dl fferent capabilities of pl ant-sol l versus stream receivers, Overland f Sow (OLF) is often deswibed as one of three methods of putt-ing waste on land (along with spray ~rrjgationand .infiI%ra%lon-percoolatfon) with the potent7 a1 advantages betng greatest on less pepmeable soils, That is, In an area of moderate to low pe~meabilityin the uppet- soil horizons, OLF is the method to use In putting wastes on land, This conception has led to some con- fusl on between 0LF and imigat%on wl th tmdf tional gated pfpe distribution of wastewater wl th subsequent Infi l &ration since both have some l iqui d movement at the soil surface* Thew is also considerable ambiguity as to what OLF actually accornpl ishes, In fact, OLF must be vjewed as a pretreatment process and not as a method for terminal land application, This distinction wd71 separate OLF from ground- level app'%.icat$on(GLA) of wastewater, Ground-level app'8"lattion can be used to distribute wastewater to an Obf system, to an trrigatjon ~nfiltratisnsystem, or to a high-rate infi 1trati on-per601 ation process. GLA is basically gated pipe or similar distributors, either pumped under pressure or utilizing gravity, in whsch 1 iquId wastewater d~scharges95-30 cm above the ground, The technology of GLA fs extremely important fn redsacl~gcertain costs assocjated wlth land application of wastewater and wlll be ddscussed in a 9ater section, The OLF process 4s defined as a pretreatment system in whleh wastewater is applied in a manner conducive to developing contro'l led sheet flow over the soil. More than ha1 f the applied wastewater is available as runoff for reuse, terminal land appl 4 cation, artif1cia1 recharge, or return to surface waters (Tpax, 1973). Waste mnstituent sepasataon and c~npde'~'sionsBCCVIY by physical, chemical, or bi~logicalprocesses which take place during Plow and during resting periods between overland flow, The 1ocata"ot-iof activity 4's at the sai 7 mIcmbfa91 mat- a9 r-plant interface, Several aspects of thi s ope~atianal defl ni tion are csi ti - cal, The first Is that there is an effluent from OLF, often 50-90 percent of INVESTMENT COSTS the incoming wastewatec volume; therefore, another pretreatrn nt 3 tepminal system must be selected to deal with thls effluent, Thus, OLF 7 ment process, The second defi~itjona9aspect is that waste conv occurr$ng at a complex Interface, and so OLF has some capacity % water consti luents, Qepending on the waste source, these cons tqtuenls may be the LLC or SLC; and therefare, OhF cob 1 d serve an effect? ve role Sn a total system, sr/li%h thjs defanftfon of the overland flow process and t~eatmenttrrechanr"srns and w%th the requirements for a pretreatment process, OLF can be ev perspective as a part of an overaS1 waste management system, Data are awl1- abTe prfmari'iy fop rnunfcjpal and food processing and cann3ng wastes since these usages currently account for over 990 percent of all existfng systems,

WSth respect to waste pretreatment the ensuing discu sion of OLF dornestl c or rnunl cipal waste and wastes from agrl cul tuml Sy related processing industries, The majoy catego~iessf waste constituents are ~evleaiiledwi th respect to documented or ant-8"cl pated OLF performance, These conse-i ti~entcate- gokSes are water, nitrogen, salts and heavy metals, o~ganic bacteria and pathogens, and nuf sarace factors For the expec%ed performance, ObF is evaluated in several pstentfal treatment modes or case studies for municipal and ag~icul- tural ly related wastes,

OLF Potentfa1 as a Pretreatment Process - Removal o~ Stabi li zatlsn Mechanisms- There are approximately 16 OLF systems which have been described In the literature wSth about 8 sf these having mun%c%palwaste ?nput, Xhfs is not a large number, and the performance ~su%ts have not been unffsrm, a%though there are definable trends and levels of treatment, The general pretreatment eapa- bllities of 0LF delfneated in the many research reports appear to be partially waste speclf-lc; and therefore, some adjustment fn mechanlsrns and magnitude of remova%smust be made when consl der-ing a new waste type, As with a1 7 1 and appl (cat%on systems, the sf te-sped fic nature of the sof 1s and t4pog~ major factors, Therefo~e,In subsequent discussion it w3 11 be assumed that the site selection, system deslgn, pera at ion, and vegetative cover are sufficient to insure that physical and chemscal performance of ObF are in an acceptable range,

The removal or conversion efficiency of OLF pretreatment must be evaluated fo~the relevant waste constl tuents, Wastewater vo%ume, o~ganics , n7trogen, phosphorus, heavy metals , salts and pathogens are major csnstf tuent categories for wha"ch OLF potentbal must be examfned, The Pjrst is wastewater volume, The potential and beneflts of 0LF to reduce the waste volume Is a complex Issue, Ffrst, OLF is genemlly used with so

I sol Js Is necessary to establish the performance and ecawomic merit of OkF, In segions of mslstufe defjcit, QLF can be benefjcsal in ~astevolume reductron whi Ie iw moj sture-excess regr ons the wastewate~wsl ume cap actually increase on an annual basrs with the use of OLF,

O~e~"landflow systems have demonstrated effectiveness {n reixsv5ng or con- vesting nutrients such as nitmyen and phosphorus, whfch is an important capa- btlitj sxce these aE the LLG or SLC for many waste types. The mechanlssns for net removals of nitrogen involve ammonia volatalf matfon, nitrification- denl tri ff cat4 on, and pl ant uptake, Nitrogen removal s are approxcimate1y 65-90 (Oversas h , 1976 Phosphorus remov 9 predom9nantl y occurs by sorption comp7 exes wC th om removal by pldnt uptake, Phosphorus removal 4s in the 30-60 percent range (Overcash, N97a), The nentrlercit removal cap one 8% the sf gn$flcant advantages for ObF; howevef, as with most bio re a's a lower l ?mi-&on effauent qua1 ~ty,The l .imi t represents the carpyover of md crobi a1 and rnq neral i zed mate si a?, Heavy metals and cation ~rneva9salso oecu~to s~gnfficantdegree fn OLFo These constituents are conseruatt we siwce there 7s Ittk plant uptake or soV- water rn+gra%?onin comparison to the amount applied, The net amount added to the sol%cannot be great because of potential toxic concent~at?ns ou" cation Imbalance, However, OLF can be designed %a provide heavy metal and catfon removal over a period of time keeping be7sw these adveirse agr-8"cesltural levels and, thus, offers potentfa1 as a pret~atrnentfor these cons&l%uentso

Finally, two factors not we71 documented but st413 present as a gotentfa? capact~ysf OLF are sys%em control of odor and pathogens, Preliminary evidence (Thomas, 1974) Ind5 cates that odors are quite 1ow with OLF probably because of the surface aerobic conditions, Thus, OLF can be used in instances requjr+ng nulsance con%sol of odor and should be compared as such to other available odor abatement techno9 ogles, With respect to bacteria dseoff, prel fminat-y data indieate is.eductisns In fecal eoa-ifsm are significant but did not meet secondary effluent crf teri a, Howeue~, system desi gn a1 tera-t~snsto enhance dfeoff have not been tested, At thls time OLF pretreatment can provjde about 99 percent fecal co l f form removal This waul d be adequate for certain 1 md-based tern1 nal rece-i verso

In summary, there ape a number of broad-range capabilities of hF as a pretreatment to be eonsjde~edin the actual evaiuatron of this techno7ogy OLF mu%% be rewewed for a particular waste Prom avai Iable data sr a meehanistlc viewpoint where data are unavai lab'ie, The princfpal advantage of 0LF ts that jt prsufdes stablllzatlaan of oxygen demand as we71 as nutrient removal, The ec~nomlcbasis In comparison to other avarlable pretreatment processes relevant to e-%hera land or water-based teminal recefwer must also be csnsfdered, In orde~to more completely detemine the imp1 ieatjons of ObF pretreatment, spe- elffc systems and waste types must be hnluded, Excellent descrlptisns of mechanisms and fmprouement-oriented research on OLF have been presented by Thomas 1975 and Hoegpel 1944,

Bve~land fl ow p~etreatmenthas been proposed for use In mwn ieipal waste treatment systems for (1) cornmnuted raw waste (possible ~4thprimary treatment) or- (2) for secsndary treated (or oxfda%!on pond) effJuent, These two waste styearns differ eonsjderably when evaluated Per the Sivlting cons%+tuent with el ther land os water-based termlnal receivers , For stream djscharge :n many states and spectfacally sn North Carol jna, theye are no simitatfsns b en mass sf specl ffc organ?cs , utrSenRs, gzgo a19 owed pep $01 ume Instead, concentration l imlts r stream quality standards have be In North Carsl%"naand githe~states for a11 seceeavfng waters as a part of the 303 ra"vet- basin p\ ans "rese l {mj ts general ly incl eede the Pd ve-day blochemi ca-8 sxygen demand (BOD5) and total Kjeldah 1 nltrogen (TKN] and where ~egulated, total phosphortis, The BODS and TKN are usua3ly eornblhed to approximate the ultamate blsehem%ca%sxygen demand (BODu = BOD5 + 4TKN) Other relevant parameters such as suspended so%4ds,volatlle sol ids, Fecal col lform, and catgons or metals are net regulated in a direct manner but, rather, are conkrsiled when levels of other waste parameters are achgeved.. The BOBU concentratjsn range of va~ious waste treatment processes for stream discharge ape 7 isted Sta Table -i and wlth these the requfred treatment level for munl cf pal p kt sources 9n two river basfns are deterninedo These levels are selected f~omjn-stream ~equbrementsas a part of the 303 river bas1 n plans For several ~yp~calbaslns In No,~%hCarol fna about 80 percent of the municjpat treatment systems have to arhjeve h9gher levels than secondary treatmento An approximate pe~centagesf rnunjcfpaT $ties, which must attain a ce~tafn1 eve1 of treatment based on numbe~sf towns and waste vo? ume, are given In Table 1 as a po%n%wference to eval uate OLF, In genera5 , the SLC for muniedpal wastes is the cancentration of BOD = (BOD5 + 4 TMN)o Phosphorus levels are set at a very low level (-I~CJTP/L~in only a few stream systems usual ly due to resewoi r s+t? ngs Howel~er, mdni CTpal $4 es are yecommended to make allowance for further phosphorus and nit~sgen emo ovals as futwe federal rqu7ataans become effect?ve? Thus, systems providing such nutrient remova% are advantageous In the long tesm, ObF as a pret~eatmentor in serjes wgth other pretreatment processes must be evaluated ln terms sf capabll~tyto ach%eve concentt-ation Iesels 9n Table 7 and, thus, as an altematfve for those conven- $1 snal psetreatments, Fop a water-based temlna l ~eceSvesthere ape several combjnat'ons of systems involvfng OLi p~treatrnentwhfch can be evaluated regarding recommended use in North Ca~~llna,These cases are as $allows: 1 OLF used for msnfna? ly treated dsmestdc waste, to satSsfy cuC~- rent and projected state st~eamstandards, Fjgure 3, 2, OLF used as a pretreatment fop effluent fmm secondaw plant, oxi dat4 on pond, OF other equi val ent processes pr; o~ to stwarn

discharge, Figure 4, In thds instance ObF is a tertlaq or adqanced treatment process,

Case l

n of QEF pretreatment of raw ornest~cwasxe js avaSlable fop stem (Kirby, 1970) and for a h~ee-yeardemonstrati on un? % Table 2, GompaFson to allowable e qua1 7%~1 iml ts indf - has 1 ower eff 1 uent concentrations th ndary treatment especla7ly for nutirzent s.em%aval, BOD5 and SS wmov ObF with raw waste fnput was bettef than acti vared sludge proce ses and cowlderably improved over oxldatlon pond effluent, c f Table 7, The OLF effTuent qua1 ?t,y was main-, tajned during warm and so51 ?$eratitag pe~lods((Thorn s , 7 974) For n 1 trogeneaus oxygen demand the OLF ef$%bent f~omminimal 3y treated domestic ~asteis approxi - mately 3 mgTKN/L, thus satisfy-ing s&i*-qgen? exi 5ttng e%$7uer? ieequj;fie- ments for TKN, The low TKN has a substantial 5mpact sn the BODu In addition, th9s pretreatment Is not just satlsfysng nltrsgenous oxygen demand but, rather, Is removing total nitrogen nd phosphorus, ApproxsmateTy 75-90 pepcent of the SMN was lost for the th~ree-jear~eoearch system dj-spping to 60 pe~centfor the long-term operation, A greater shift from 55-85 percent down to 35 percent was evfdenced for phosphoruso However, even with the potentla1 aging sf the system the resultan removal of nut~ientsremafns si gnlf i cant and rep~esentsa substantial adu nced t~atmenteffect of OLF,

ObF pretreatment to achlege the phosphorus rest~pictionsof 1 rngTP/& does not appear- feasjble wixh typlcat OhF effluent levels being about 4 rngTP,/R. Convenlel onal secondary treatment effl uenteev"ieenees 1 S ttB e phosphorus removal ( 11 mg%P/~),Table 1, Most of the stream qua1 ity stand ~dsare for %he @on=- centratkm of BODu = BOD5 + 4TKN and calculatlsn of this vahe for OLF yields 20-35 mg BODu/R. Listssng the nominal, levels of waste treatment and res BOD, values, Table I, OLF can be judged as ranlc{ng between advanced $re and secondary wlth nj ts1$9cazson, FOP the tvlicr ~.e'verbasfns investfgate FolS wfng prlma~yt>eatmnt could provl de treatm nt. fo~50-70 percent sf the munlci pal systems, T&I s h~ghlevel of &peatmen&means that serious cons?deration must be given to OLF of raw munici gal waste The other parameter concentrathn and percentage removals achleved by OLF pretreatment are given -in Table 2, The OLF eff9 uemt dfd not meet stream calf- form restrictions as an fndfcator sf ather pathogens (Thomas, %975), There- fore, just as wCt& act~vatedsludge or sthey seconda~~ytreatment OLF effluent must be cklroinated or d%slnfectedprfst* to stseam d$scharge, Alumlnum sd7- fate, added to enhance phosphorus removal, was also absorbed on the soil surface (Thomas, IgX), The degwe to which thjs was prec+pf%atjonand for what length of time thls removal would exlst have not been eseablished for OLE sys terns,

For stream receiver systems the1t-s ape d7$fis~ltlesjn putting OLF of raw ~astein perspective wd th alternative systems, Primarily, this s because

recelvew having phosphorus restrlctlons, The cation removal, Table 2, was not as good as OLF of raw domestlc waste wlth there being vjrtual ly no removals from secondary effluent, Since cation removal can OCCUP fyom interactjon with the sof 1 or by prec~pi tation wl th waste saws tjtuents , further examinat+on lndi cates that probably the a1 umlnum removal wl th raw domestl c w ste (Thomas, 1975) is due to the latter rnechanjsm and that jn genera; catlon removal Is not accompl ished ewtensi vely by means sf present OLF pretreatment systemso Case 3 Many munlc%palltfesand development areas are faced presently or in the future with the task of providing new waste treatment facilfties, Stream con- straints, as shwn In Table 1, often require secondary plus advanced waste treatment or advanced treatment, Under these csndit'ons serious consjdesation must be gi wen to OLF as a secondary treatment fo'llowed by tert;ary pr The major advantage of OLF in thf s mode 4s that In adda"t4 om to secondary treatment, nitrogen and phosphorus emo oval Is also accomplished, Thus, subsequent advanced processes need not be a% sophist-icated or do not have t such high levels of efficiency. Reviewing the effluent qua1 i ty from OiF treatmen% of rn~n-imallytreated municipal waste, Table 2, the levels of BOD , TKN, and t-PO,+-P are 40-25, 2-3, and 4 mg/&, respectf~ely~In comparison to the c~iterlaof e20 mg BOD,/L and 1 mg t-PO,-PgL (where phosphorus is ~egulated)for the most restricted stream reaches, the effluent from OLF needs primarily phosphorus t-emovaa and some @OD5 or TKN reductfon, Quite possibly, a filtrat.e'on of OLF effluent would be a99 that is required shnce levels of 5-7 mg BODsJR and 754 percent removal of phosphorus are typi ca%ly obtained wi th these unlts, A%ternatlvely, ni trifica- tjon of OEF effluent to =d05mg TKNjR would also satfsfy advanced treatment requl rements, Research on injection of aluminum sulfate Into mlnimal4y treated domestic waste prior to OLF has shown that a further reduction in t-PO4-P to 2 mg/R was attajned (Thomas, 3975)- Thls appmach enhances the OLF mnoval capabi 1 ltles thus reducing subsequent tertiary treatment requi rements;

Mundclpal Waste - Land Based Terminal Receiver C The land area for mlnima7ly treated domestlc waste is contro9led by the ni trogen content (Overcash, %975), For secondary effluent or effluent from an oxidation pond sufficient nltrogen separation and loss has already occurred so that water or hydraulic lsaddng is the LLC (Overcash, 7975), Thus, pretreatment processes such as OLF must be evaluated for cap&%1 ities with respect to different const%tuentsfor rnfnimally treated versus secondary treated effluent, Several combinatfons of 01F followed by a spray lrr?gatlon system are probable, These are as follows: 4" OhF used as a pret~eatmentof minima%%ytreated waste prior ta land application, Figwe 6, 5, OLF used as pretreatment of secondary plan% effluent prior to land applleation, Figure 7, staxe and federal regu i a%fons usual li y cover only oxygen deman levels, suspended and total solids, and metals being unspectf ment ~equirements, Bas-ical ly, these regulations assume cocve processes fop wh%ch effluent parameter r t4ss and in-stream behavbr are well known. Thus, with contro7 f a 1 irn4"ted nurnbe~of paraanete~sa71 the also restricted, Land-base psetreatments or other evolving techno1 o not exhl br t these efF7 uent aramete~ra~i ss ; hence, reformu%at i on or more extensf ve speci f icatl on of xisting effluent csnstra~ntsmay be needed:

Although data ape available for OLF used as a terdiai~yprocess, bgure 4, fol lowlng one of several secondae~treatmertts, hbke2, these refe~encesare not extens%ve and, heersce, do not a1 TOW precjse pretreat~lentevaluat40nc The ty of secondary t atmewt used prior to OLF include oxqdat+on pond, tri ck9 lng filter, and act! vated sludge. swevep, wlth the me hanf sms operating durlng QLF certain cowc7us1ons ca hedo Secondary %re ted effluent is Jaw 10 concentration of o~gan~cs jns app~ox*imate; y x e same amount sf tom1 nltrogen an phosphorus as raw domes%?c ~aste, N-I trogen may ewl st in any of several forms, 0-N, NH3-N, or NO3-N clepend~ngom the secondary treatment p mce ss -

With respect to a water-based rece?ver, OLF of second y.y effluent yselds 50-60 percent reductson of BODr and SS to a level of about %O mgaR, Because 92-96 percent reductfui sf these parameters occurs In the ftrst pretreatment he convent! onal seeondaq unl t processes) , subsequent ~eductionsare matic, In fact, when OLF fs used as the only pretreatment process te +nstead of as a second szage advanced ki+ea&men&process, similar BOD5 and SS effluent quality i sul ts, The 1ack of greater subsequent BOB5, TKN, SS, or TP removal when usirzg secondary efff uent for OQF input r s primarily due to background levels of pa~tfcles,m(nera9ixlng vegeta$%ve cover and micro- srganjsm transport fn the Obf effluent It should be noted that future research may furnish desl gn and sperattng cr?tesia %or kmproted OLF performance, Addit~onally,design recommendatdons are for the same hydmulic loading to be used with both raw and secondary effluent so that the two uses of O%% would require nearly the same land area; hence, maklag the use of OLF to seduce oxygen demand after secondayy treatment of questionable economic ba3uer ObF rnlght serve as a denitrif~cationscheme for n?trates formed in gre- vlous waste pretreatment since saturated soil conditions ex5st- V9ewed from another aspect, OLF rnj ght provi de f nexpens l we aerat: on and n9 try+cat+on because of the thfn sheet f%owwith ant~mateair-Ifquid contact, Neither of these postulated advanced treatments are re1 i ably demonst~atedin avail able 1 iterature, The most detaa led study [Neyer, 1974) concluded that the low oxygen demand In the secondary input precl uded major denj t~f$7 ca%i on even under favorable sol 1 -water saturated eond9 tions, Otke~resea~chers found 90s percent ~ernova.7 of nf trates (Carlson, $974) and over I00 percent increase of nitrates (Thomas, 7975)" The resultjng conclus

Phos~horusremoval , being dependent on interact9 on and ssr~tionwi th the soil , was' sf mf lap to that effected by OLF pret~atmentIn Case 8, The resulting effluent of about 4-6 mgTP/%, Table. 2, Is stqfl unaceeptab e For stream reeel vers having phosphorus restrlctl ons, The cation removal, Table 2, was not as good as OLF of raw dsmstlc waste wSth %here being vfrtually no removals from secondary effluent, Slnce cation removal can occur from Interaction with the soil or by precipitatgon wlth waste constituents, further examinatjsn indi sates that probably the alurn? num removal with raw domes t$c waste (Thomas, 1975) Is due to the 'latter mechanism and that in general catlosr removal is not accompl5shed ewtenslvely by means of present OKF pretreatment systems,

Case 3 Many rnunfclpal t tfes and development areas are faced presently or in the future with the task of provldlng new waste treatment faeillt-ies, Stream con- stralnts, as shwn fn Table 1, often require secondary plus advanced waste treatment or advanced treatment, Under these condl tisns se~iouscons3 deration must be given to OLF as a secondary treatment fol7swed by tertiary processes, The major advantage of ObF in th%smode is that !n additlon to secondary treatment, nitrogen and phosphorus removal Is a1 so accompl ished, Thus, subsequent advanced processes need not be as ssphlsts cated or do not have do operate at such high levels of efficiency,

Reviewing the effluent qua1 ity from OLF treatment of minimally treated municipal waste, Table 2, the levels of BOD , TKN, and $-POk-? are 10-25, 2-3, and 4 mg,& respectivelyo In comparison to the crlterja of 40mg BOD,/& and 1 rng t-PO&-P/R [where phosphorus is regulated) for the most. rest~lctedstream reaches, the effluent from OLF needs prlinarily phosphorus removal and some @OD5 or TKN reductlono Qulte possfb'ly, a fl9tratfon of OLF effluent would be all that is requlred since levels of 5-7 mg BOD5/R and 751 percent removal of phosphorus are typical ly obtained with %hese units, ASternatlvely, nltrifica- tion of OLF effluent to d05rng TKN/% would also satisfy advanced treatment requi rements, Research on injection sf aluminum suTfate Into mlnlmal %ytreated domestic waste prlsr to OLF has shown that a further reduction in t-P04-P to 2 mg/& was attalned (Thomas, 1975). Thfs app~oachenhances the OLF removal capabi % f t?es thus reducing subsequent tertlary treatment requirements,

The Sand area for mln3malIy treated domestlc waste is controlled by the nltrsgen content (Overcash, 1975), For secondary effluent o~ effluent from an oxidation pond sufficjent nitrogen separatjon and loss has already occurred so that water or hydraulic Ioading is the LLC (Overcash, 1975). Thus, pretreatment processes such as OkF must be evaluated for capab?lities with respect to diffe~ntconsti tuents for mlnlmal %ytreated versus secondary treated effluent,

Several comblnat?ows sf OLF $01 lowed by a spray irrigation system aye probable, These are as follows: 4, OLF used as a pretreament QP minimally treated waste prior- to land application, Figure 6r

5, OLF used as pretreatment of secondary plant effauent prior to 1 and applfcatl on, Figure 7,

6, Ground-level applr cation (GLAQ s a techwlqbe for reducing i st9 gats on-S nPi T tV?a%sonsystem costs,

When cons"eee1ng the land as the terminal rece'uer for raw dorirestdc waste, zhe total n+trogen content Is the LLkC, Table 3, The~efsre,OEF must be son- slde~edfor nitmgen remcsval capabjl it-ies df tfi is to be viable as a pretreatment process, The avepage 06; effluent con entration of total nitro mgTN/C, thus resulting in a reduct4sn of 60 ta 96 percent 0% the raw %ion of the kbC for bF eff3uent iridscates at the 3-70 mg TM/L range tent ate hydraul le lo ding is rimitlng, Table 3, Removd of only 20-30 f TN Prom raw waste msults i~ an effluent which %swater Slmited, In essence, 6LF systems as reported =in ava-ilable research were designed to maximize removal of waste constituents; but .IP Ian terminal recel ver, then shorter OLF distances ear greater hydraul ic loading rates could be used to remove about 30 persent of the domest+c TN

Used in thls manner, the OEF technique can remove nltrogen in a ma71 area thereby reduclng the total land area for raw waste appl3eatlon by about 30 percent" An example of a total system schemat3c and larid balance 40s gfven in Figure 6, Since only a small percent emo oval of n~trsgenProm domestfc rnun$cipal waste -is needed, the major capabiljties of- OLF n"rogen rem utjlized to the full advantage, OLF as a secondary treatment prior to land applicatfsn does offer other signfficant advantages, sfnce at the present tgme some form of secorldary treatment is mandatory in the U. So prior to land application- Khjs regulation, al though not scAentifically justified in every Snstance, does exist at thTs time. Under thas constraint, OLF as a replacement for conventlsn treatment has lo we^ operational costs and after some prescribed S substantial value as a usable land area, Under these csndit?ons the economic advantage 05 njtrsgen reduc"eon and pretre tment system salvage value must be balanced agalnst the cost of interfacing OLF pretreatrne~tand terrn'na7 land appl icatlon, Case 5 Suggestion for using OLF Pol 7 ow%ng secondary treatment of nun- crpal wastes has been made (Abernathy, 7976) Sn which the final effluent could be appljed to the !and; e,g,, by spray fr~~gation,The $LC fo~seconda~y effluent is water or hydraul~capplication rates, Table 3, In the Snstance sf a water-lsmited waste the economlc potential of usfng OLF =is net easily determined, As dlseussed %n the tseatmnt mechanism sectjsn, the relatfcmsh~psbetween sof7 type, spray .P"r;rlgatdon desi; gn, and the rate of water loss OY percolat'lsn are not fully documented % pprctscal systems, In the extreme sf a very {mpermeable sof 1 there is probably no greater percolation 7 oss in OLF as corn- pared wl th spray $nfiltratlon appI?ca%lonmethods, Thus, no pretreatment benefl t is devved from OLF, If a moderately permeable $019 is used, then ObF research Is needed to clarWy the jncrease ar decrease -in tota'l system land area required w+ th the use of OhF to yemove water and then land i3ipp"sats"on of the ObF effluent versus complete ivrigation appl kction of the water-7 imi ted wastewaterc At this tame the cost advantages of such an OkF system do not appear to be s

Genera- Waste ass?ml - Domes ti c waste tion, latory capad ty, source 'arame ter P Pri mary treated N 4,2x%O4 Total oxygen demand 3,5xI 0"

H2O 4 ,4xlO" Secondary treated N 2,8x10Li Organ%"cs 1 ,4x904

H2O

Case 6 As dlstinct from the Implications of OLF in the ffeld of w.miclpa% waste treatment, ground-level appl lcation (GLA) a1 so offers considerable advantages In reducing total waste treatment costs, In North Carolina and several other states one sf the primary design restrictions Is to provide a buffer distance, usual ly of 30-1 50 m to minimf ze dri ft potenti a% of sp~ay-generatedaerosol so Whlle the exact buffer zone Is not sclentifical%ydeflned in terms of ~elative health rl sks, the requjrement Is a part of each 1 and-based system- Under the constraint of providing a fixed buffer, sogo, 60 m between spray fleld and adjoining property, GLA can reduce the t~talsystem costs, Assumlng that the hazards of GLA of secondary treated municipal waste are as acceptable as the health effects of styeam dfscharge of the same effluent, then only a nuisance buffer mone of 7-15 m would be required adjacent to GLA of munic~pal effluent, Figure 80 The total 1 and-based system would contain three parts and be only slightly larger than the land area ac%uall%yrequired by hydraulic design considerations, The savings l'n? reduced land purchases for a buffer mone would be 90-30 percent of the total css%s, The central area Ss then a spray jrrigation field ringed by the second area of GLA, This GLA area would be more expensive In land preparation than spray Ir-rlgatlon but less expensive for equfpment and, most importantly, electricity operatjon costs slnce very low pressure speratlon would be required, Additionally, the significant and large savings in not purchasing a 70-TO0 rn buffer zone would greatly reduce the total land system costs, In fact, in many instances careful con- slderatiow of GLA for the total system should be considered as a viable alterna- tfwe, even where only grass crops are envislened and land preparation may be extenslve, because of the savings in buffer zone and power operational costs,

OLF MunIci pal Pretreatment Summary Based on llmated available data, OLF w+th exfs04ng deslgn crGteria4s cost effective as an alternat%e to secondary treatment of rnunicTpa.1 waste prior to stream discharge or, if needed, prior to adbariced treatment and stream discharge, That fs, the considerable staba~izat

ObF as a Po~mof secondary treatment substantially reduces nitrogen and pathogen levels to make a't an effective pretreatment of raw domestla: waste prior to land appllcatlon as the terminal reeeive~, In the fleld of overland flow, several research needs exfst to fully assess the advantages and 1imi tatl ons of 0&& These t nformatl on gaps Incl ude: 1, Yo assess the pretreatment of wastes in which water is the LLC by the comparison on an annual basis sf percolatton losses by ObF in whlch runoff Is collected routsnely versus spray Irriga%?onfn wh%chrunoff is prsh%bi%ed, 2, The design criteria which produce varlsus levels of patha- gen dieoff in OEF pretreatment and the long-term behavior of ObF in thSs regard, 3. Better understandjng of which soil properties will effect the satl sfactory behavf o~ of OLF pret~eatmentsystems,

4, Increasing the general use and understandjng of ObF so that desl gn speci flcations can better match the particular treatment needed and so that total system costs are ?educed,

Agricultural and Industrial- Wastes The predornlnance at on-gafng OLF systems outsfde the municipal field have been in fruit and vegetable cannlng* However, the treatment capabj lftles of ObF delineated in these studles are applicable to other agricul %bra1 and Indus- trial wastes l f conslderat4on f s given to removal mechanfsm, l jmi tations , and the overall system object! ves, A summary of reported system performance, input characteri stlcs , and sys%em desagn factors for agri cul %u*a%ly re1 ated OLF systems are included in Table 2, The waste input f~omcanning processes generally has 4 to 6 tfmes the organjc content, s%ightly hlghes nltrogen levels, and approxi mately the same phosphorus concentrations as raw dsmestl c waste, The elevated organic content is thus the distinettwe feature in the existing i ndus tri a%OLF sys terns, Other agr~cerlturalwastes, e,g<, animal manure, and a number of 5ndus- trl a1 wdstes are character$st+ cal ly h7 gher in wu t~fen-cand catbo eve7 s with consomms tantly I owes waste vol umes than those wastewate~sp~esent; y used fn food processsng 0&%systems - Therefore, cape musk be exeopcised in extp8 :ng results os In predscting the mare beneficial uses of OSF pretr agpi cu4 tuml and Industsj a1 wastes,

As a pretreatment, OLF c ue be used prior to a water--based ot- a land- sed termfna7 receiver. Mith respect to a stream receiver a us municipal section, the OLF effluent qwali ty is ~egul of oxygen demand, either BO 5 0r WN, Because of the Snherencl~higher organic loads, the BOD5 concen%rat

The nftrogen and phosphorus removal in existing food p~oeessingObF systems is s1m3 lar to that found wl th raw domestic waste Eff4uent 1 evels aye 3-95 mg TNjL(80-90 percent reduction) and 3-7 mg VjR (60-80 percent reduction). Agaln, OLF is providfng sustained high-level ol f ds and BOD5 emo oval as we 17 as excel lent nutrient removal, thus cons%desably exceedsng conventional seconda~y processes, It is a~tfcipatedthat wlth other more csncent~atedtypes of agri- cu3 tural and ~ndustria7 wastes ObF pret~eatmentcan eon~inueto gf ve subs tan- %la1 srgangc reduction at the same time as nltrsgen and phosphopus removals rernaln at least at the 60-80 percent and 40-60 percent levels, respect~vely~ In order to insure a h%gh KeweS sf removal in oxygen demand %nthe pse- 1imindr.y plannlng and east estimation stages the use of OLF followed by a atment unat process would appear necessary, Figur 5, Processes such as flitratlon or post aeration could be used to produce BOD, below 20 mgXR, thus meeting strjngent stream requirementsA Such a series of pretreaz- ment processes pr9or ta a stream receives would offe~advantages of utilizing the large oxygen demand s tabi 7 -n" za%"in and sernoval capacity demonstrated w%th OLF- Pilot scale and demonstration studies of this type of system should vesi fy the economl cs and pe~fo~mancebeneFi ts for ag~icul tural and indvstri a? wastes , For land-based terminal receivers OkF offe~ssome 4ndustnaS waste pretreatment advantages, pmncfpal ly %s.r nt trogen removal, A number of waste types have nit~ogenas the substantial &LC, Although the systems Tn Table 2 are not substanti a1 ly nitsogen 1 {mi ted, the removal mechanisms can be expected to apply to more concentrated wastes, poss~blywlth some reduced ef$!c'iency, Thus, a sysxem of an 01,F ayes followed by frsfyatfon-fnfjltration, FSguse 6, would provide s%gni$fcant advantages, Fn cwder fo~OLF to functkn tdl, the so74 pe~meab%%+tymust be low such that d?~ectirrlgat;on would be at a very %ow range 0,8 - 1,2 cmjweek, A concentrated waste such as swine manure requj res about 12 ha, per 4800 hogs for nl twg n asslmflataon and about Q,4 ha, per 1800 hogs for hydrau'l%cI lmfts (0,8 crnhveek), Thus, w"kh an application sf 70-15 cm8week of swjne wastes and 75 percent reductio~7n nixrogen, an OLF pretreatment slte of 0.02 hac would have a te~mnallaaad requirement for OLF effluent oF 3 ha,, and the t~talsystew needs would be 3,02 ha In carnoamson to the 12 ha. per 1000 hogs for direct land application at recommended nitrogen rates the OLF pretreatment terminal 1and appl ication cornbinat?on requires 75 percent less land area. In this manner, OLF pretreatment, even when terminal Sand application rates are low, has a significant impact on total system costs, A si mi l ar analysis cdul d be performed for phosphorus-I imi ted wastes a1 though not many of these are presently known, An analysis for industrial waste in whf ch cations, salts, or heavy metals are limiting cannot be done at this time because of the lack of field data as a verification of plant-soil mechanisms and the long-term removal efficiencies. For salt or heavy metals constituents combinations of OLF, ti1 lage, and rest periods might provide sustained removals. Research on OLF for a variety of wastes with different SLC or LLC is needed to establish the full benefit-cost ratio of OLF pretreatment. SECTION I1

RESEARCH OBJECTIVES

Overrdnd 41a1d 5% %nthe first category sfnce desygn js or;ented toward sr;art

An overl~~e~~of basic n; trificatson and denjtrificatisn ye ctions 4s shown in Table 4, lhls sequence aF reactions results in a net loss f nltrogew as N2 gas PY~Ia process(es) which these reactions are occurringa Aerobic and anaernb; c conds tions permitting n"~i fication-deny %anlffcat4 on during flow wfth the uppep Jlqufd receib~sngoxygen and an anae~ob3ccsndlt*on or (b) duping the resting-1 iquf wh-ich can be cont~olkddo ggl ve periods sf arrobi L drying, The net loss of nitrogen as N2 enhances the ObF perfor~ancefor the objective a% reductng the LLC in animal daste, The ~esearchof th;s projece $ cused on evaluating riows aspeas of waste trans format?ons during over1 and TI ow,

l uate the concentrat %onand mass changes QP nftrogen =fn pou%try waste as affected hy OkF ~4thdi r- tances fxom 15 rn to 45 m, 2, bs determine the effect of waste loadfng rate and cyc7 fc 50-11 d~y.gi7ngon OLF efflwnt quai Fty obtainable by control P management v 3, %a cmpare seve~aianethodo1ogl"es foi6 measusing the tsans- formation sf nitrogenous compounds in OLF, These incl wde -.

Table 4, BIOCHEMICAL REACTIONS OF NITRlFY ING AND DENITRI FY ING ORGANISMS

Type reaction - Steps NITRIFICATION 1, 6Nituloaomonas) 2, (Nitrobacterd Overal l Oxi datf on

DENITRIFICATION (oxidation of methanol )

Overall Reaction

TKN removal, nitrate formation, nitrifying microorgani sms , and oxidation-reduction potential, 4, To project a farm-scale system which utilizes OLF as a poultry waste pretreatment. SECTION TII

EXPERIMENTAL DESIGN AND PROCEDWRES

The fleld instal lation cor~s'lstedof a caged l aye^ house, terraces, and two lagoons, Figure 9, The ter~aceswere design of the manure from one a9 ley (9400 birds) of %he caged layer house, The flush water for the experimental alley was recycled from the terminal lagoon and temporarjly stored in an suts%detank, Flgure 9, Once per day the manure was prewetted wjth hOOR to 9100t and then the entir-e flush tank (8200L) emptied into the alley. Th?s method kept the PJoor cle only occasional localized scraping, It should be noted that du the number of birds did not remain nstant and flush volumes were changed prsportiona3ly to maintain a atl lo 82001: 14°G i~i,jb~d,~ The flushed wastes passed through a coarse feather trap and Into a mixing tank eri.11 ch upon fill ing activated a control system and started the slurry tank mixing pump. After agi tati on the slurry was pumped to the terrace overland flow system, The ove~landflow (OLF) site consisted of three terrace systems (A, B, C), each containing three nearly Identical terraces in series, Figure 9. Differences between terrace systems were in slope and dimensions , Figure 9 and Tab3e 5. Terraces 7, 4, and 7 were referred to as top; 2, 5, and s middle; and 3, 6, and 9 as bottom indicating the direction and distance of flow, Figure 9.

Table 5. DIr4Ei4SIONS AND SLOPES OF TERRACE SYSTEMS

The waste slurry was pumped from the slurry mix-tank to a dlstrlbution box which was constructed with a rotating bucket and baffle network used to regulate the amount added to each terrace system, Figure 90, ThSs distributor was developed with large orifices to prevent clogging oT feathers, egg shells, and debris and still provide accurate subdfvislsn of the slurry to the desired terrace system. The waste slurry was diluted with water from the terminal lagoon, the amount of dilutlon water cont~olledby a constant flow orifjce regul ator (Dole Fl ow Controls , Eaton Corp. , Carol Stream, I%1, ) and was then applied to the top terraces by means of a gated, g~ound-level trough, Flgure 9 7 This arrangement a1 1 owed flex?bi l i ty of waste magnitude and concentration of 1 oadings. The operational arrangement pumped wastewater to the terrace system

LINE FROM SLURRY DISTRIBUTION BOX \

DISTRIBUTION TROUGH - GATED

DISTRIBUTION

PLASTIC LINER, lOcm BELOW SOIL SURFACE AND OVERLAPPING COLLECTION TROUGH

DISTRIBUTION TROUGH WITH GATED SLOTS

ISOMETRIC

COLLECTON TROUGH / 8 V-SHAPED FLUME _-- (SLOPED BOTTOM )

I i - - -- DISTRIBUTLON n.-iZnns*a TROUGH LEVEL)

\ SLIDING COVERS

-----HORIZONTAL VIEW for a total of 120 minutes at which time the slurry pump stopped, and the recycled lagoon water was pumped to the flush tank, After fl owing across the top terrace in each of the three terrace systems, the wastewater was collected in a center sloping trough, passed %hrough a V-shaped flume, and redistributed through a gated, level trough, Figure 11. Distribution was adjusted using sliding covers at each opening of the distribution trough to provide nearly uniform flow onto the start of each of the middle terraces. The V-shaped flumes were ca%ibrated to relate helght of flow to fl ow-rate. Flows from the middle terraces were co%lected and redi stri buted to the bottom terraces in a sl'milar manner, Following the bottom terrace in each system the effluent entered a lagoon which overflowed into a larger pol lshing pond. From this pond, water was pumped to flush the house or to dilute the manure slurry. The soil type in the OLF site is in the Cecil series, a dominant soil in the Piedmont subregion of the Southeast, After site preparation the Bt horizon was wtthin 90 cm of the surface. The permea- ies and other soil characteristics of thfs general ble 6, At this pa~ticularsite an analysis oi the ducted (Aull, 9975). Surface samples of the upper 10 crn were taken from each terrace, and all were in the clay loam textural class, The average and range of values are given in Table 6.

Table 6. SOIL PROPERTIES OF OVERLAND FLOW SITE

The terraces were seeded with a mixture of Reed Canary, redtop, and fescue grass seed. There was a variable mixture of these grasses from terrace to terrace, but the Reed Canary had become dominant over a one-year period of waste loading rior to this study, (See Sectlon 111-Hlstorical Background of OLF Terraces 7. ' A 112 to 1 meter wide strip of fescue grass, however, was predominant across the bottom of each terrace. This strip corresponded with the width of plastic liner placed 10 cm below the soil adjacent to and overlapping the edge of each collection trough to prevent movement of water under the trough at the interface between the metal and the soil.

Hi stori cal Background of OCF Terraces For approximately a year before the intensive monitoring of the OLF, terraces were acclimated with appl isations of poul try manure, The app1 isation was as overl and flow, but a seven-day-per-week schedule was net ma-! ntained, This initlal period p~ovfdeda we%4 -established sod and Introduced a substantial waste quantI%y over an extended time period to bring the sol 1 into conditions simulating extended OLF usage, Immedfately prior to Intensive won i toring the system was allowed to rest for three weeks wSLh no waste or w ter appl icatf on,

Three bas1 e parameters were ccnsl dered under which to estab l ish df fferent loading conditions Prom each terrace system, Table 7, Frequency of loading was established as a parameter to study the effect of rest periods on pollutant removal so This may be consjde~edan aerobfc-anaerobk cons%"der'.atjon,in which a constant waste Soad was =introduced two hours each day wfth 22 hours rest (System 6%or two hours evevy other day with 46 hours rest (System B), In "chis mode, the abi 1 ity to dry and produce an aeroblc surface zone could be observed for two levels sf operational control, Flow raze, const~tutangthe total hydraul?~load reledsed to the terrace per uni t time, was chosen as a variable to Incorporate washing effect eonsidera- ti ons and sesl dence time effects, Table 9, Here agafn, aerobi c-anaerobic con- sideratlons came anto play but to a lesser degsee during the short perlod of was tewates fl ow, The total nltrogen load applied to the terraces was establ lshed as a third parameter, Since dai ly loading duration was the same for all plots, an inherent component of this parameter is different nitrogen concentratfsns of the wastewater being appl Sed to the terraces, The dil utlon water was used to achieve the desl red concenkratl ons, Table 7, The bas: c cons? demti ons were the dl ffering amounts of n! trogen avai lable for plant nutrient, mlcrobial substrate, volati7izat:on, and soiT sorption. The amount of n4trogen that can be physically removed from the flowing liquid by settling due to its assosfation with particulate matter was invest1 gated, The terrace systems were assigned different parameter unft values as a means sf comparing the variables as shown In fable 7, with Terrace A asslgned a value of 1 for a1 1 parameters, Terraces A and C were to be loaded every day and B once every other day, Terrace Systems B and C were to recefve the same quantity of waste (1680 kgjha-pyr) and, therefore, represented the effect of different periods or cycleso Terrace A received one-half (840 kg/ha,jyr), the waste load of Terrace C, and the same frequency of loading, and one-half of the hydraulic load, Thus, A and C represent two rates of waste appl lcatisn or land area r&quiremw%sper unit number of b?rds, Campa~isonof Terraces A and B provi des information on two levels of waste app4 icatfon and frequency of application, In a similar manner comparison between Terraces B and C provi informatfon on different Prequencles of appllca%%snbut similar njtrogen %sad- ing rates, Duratlon of a91 IoadTng events was set at 120 rnlnute~qdily~ The system was set up to del

Numerl ca% averages of concentratf ons and hydraul ic 1 oading rates for the study are shown qn Tables 9 and 10, respectively, The weekly hydraulic loading is based on the total area of the terrace system, and It should be noted that Terrace B was larger than Terraces A and C (20 percent 1 arger). Also, since the study Basted 971 days and the area of each system was considerably less than a hectare, the total quantity of nitrogen appl ied was proportionately less than that which would have been applied on a hectare-year basis. Table 11 presents the effectfve loading rates of nitrogen and wastewater based on the areas of the individual terraces within a system,

Table 9, PARAMETER AVERAGE CONCENTRATION IN APPLIED WASTEWATER, OLFi

Table 10, AVERAGE OMSYSTEM LOADING RATES OF NITROGEN AND WASTEWATER BASED ON TOTAL AREA OF INDIVIDUAL TERRACE SYSTEMS

*Testfng period was 17% days

For descriptive purposes average input concentrations of total organic carbon (TOC) , chemical oxygen demand (COD), total phosphates (T-P), and chlorides (C4) are ljsted in TabTe 9. It is noted that the Tow carbon to nitrogen ratfos (3,5 to 3.6 in these cases) present a condition whereby the mineral lzation of njtrogen is enhanced thus making it better available for plant uptake (Gray, 197%) Wastes with a carbon to nitrogen ratio less than 10 to 14 support large rnlcrobial populations and decompose readfly (Phelan, 1975), Environmental conditions such as the degree of aerati on, however, inf l uence numbers of microorgani sms and decompos i ti on rates. Table 17, EFFECTIVE ObF LOADING RATES OF NITROGEN AND WASTEWATER BASED ON AREAS OF INDIVIDUAL TERRACES OR TERRACE COMBINATIONS WITHIN TERRACE SYSTEM

*%estlng period - 171 days

Wastewater Loading Samples Samples of the slurry from the distribution box were taken prior to any dil utlon and samples of the dil wt ion water from lagoon 2 were taken at the same Socat70nso Slurry samples were analyzed for total Kjeldah'l nitrogen (TKN) and ammonia nitrogen (NH3-N) Di lutlon water samples were analyzed for TKN, NH3-N, and nitrate nitrogen (NO3-N), From these two input concentrations and the respective flow rates, the lnput wastewater concentration reaching each terrace system was cal cu'l ated, Poultry wastes contain 1-w"ttle or no n%trates; consequently, the concentration sf NO3-N in the slur~ysamples were considered to be equal to that of the dilution water, since the flush water came from the same source as the dilution watep, For the waste used the NO3-N comprised only a small proportion (0,l4 percent to 0,25 percent) of the tota3 nitrogen (T-N) applied, Samples were taken once a week and analyses were by Standard Methods (APHA, 1971) and demonstrated adaptations fo~anlmal wastes (Overcash, 1975a). Wastewater Runoff Sampl es Runoff samples were taken once a week during the same sampling period when slurry and dilution samples were taken" Samples were taken at the 601- lection trough at the bottom of each terrace and were taken along four quarter sections of the trough to attaln a representative sample across the termce wjdth, Samples were differentiated as to the type sf sample and the tlme of sample, "Type" of sample referred to the residence time of the wastewater before ini tial runoff began, Sampses In quarter sect?ons where runoff fjsst occurred were termed "channel" samples, and samples Prom the other quarter sectlons were termed "regular" samples, Thjs $so%ati on of "channel " samples was incorporated due to the development of small channels on some of the terraces, Di stlnction between channel samples (where the wastewater bad a higher velocity and, consequently, spends less tlme on the terrace) and regular samples a1 lowed for analysis of differences between the two (Section IY, Concentration Reduction-Channel versus KeguS ar (nonchannel ized) Flow), The ~egula~samples were cornposited as a sjnyle sample, and the channel samples were cornposited if runoff initially occurred at more than one quarter ection, Time sf sam referred to the time when the sample was taken rela Ive to the time when off began, whether at 0-hour (a'nitlal runoff), %/2-hour, I-hour, 1 I/2-hour, or 2-hours, Thus, samples were identified as to heir location (terrace num- bek), time, and type; e,gi.,, TI-0 hrs, channel, T7-1 hrc regulars T4-% hr. chan-

Sampkes were preserved for transport to the laboratory by adding 1/2 mt of concentrated H2S0, for each 200 mL of sanple. Standard Methods were used to run analyses of YKN, NH3-N, and NO2-No Organic ns"trsgen, concent~at%"onswere erived by subtracting NH2-N from TKN,

Cooperative research with the Soil Science Department of North Carola'na State Uni versf ty provided data on the analysis of g~oundwatersamples taken at P each terrace at depths of 0,30 m, O,9l m, %,52m, and 2,44 me taken by a 1 x loS Pascal porous cup, suction method, at monthly so Varjous analyses were run Inchding I\IH:t-14 and NO3-N, A NH,-N was by the specific ion electrode and analysis of NO?-N was by a method developed by Lowe (1967).

The basic interest in the nltrogen concentratlon in the groundwater is at the 2.4 m depth, as sh 1%be establ ished later, 'The NH,-N concentration at thls depth was found to be insigniff cant (less than On%mg/R), Coupled with the hypothesis that the organic nitrogen concentrat%onat thls depth is also -9"nsl"gnjficant:"(Humena'k, 19751, the T-N concentrati on was defined as equal to the NO?-N concentratlon. Grass Samples Each terrace was schemat-ically djvlded into 100 equal sectjons and 5 sections were randomly chosen on each terrace for 'locatloras of grass sanipl-!ng plots, Figure 72, A single grass sampling plot consisted of ?m x 7m square located wq%h=in a randomly chosen sectlon. These were sampled once a week by hand c7ipping the grass at a height of 3 to 5 cm0 Yields and d~ymatter contents weye determined for each weekly sample, and appsoximate9y 9 out of 4 weekly samples were analyzed for T-N by the Mjeldahl method and for NO3-N by methods deve! oped by iowe (1967) - Total yields for entire teryaces were determined by the ratio sf sampled are2 to total ab*eac Some c~rrectionswere made for n~n-growth areas of gyass sampl ing p7 ots (Covi 1, $976), N'1: trogen %n RaSlafal? Runoff NI trogen c~ncentrationin ral'nfall runoff was not ~"outmelymeasured but was estimated from data collected at a compana"on rainfall runoff experlrnental sf te nearby, A value of 8 sngJN/R 2n radnfal "lmofr" was used, Further discussion !s prsefded in a later section (Sect5on IV, Nitrogen Losses\, TERRACE WITH 700 SECTIONS OF EQUAL AREA

r TERRACE # I W I L 1

SECTIONS RANDOMLY SELECTED FOR PLACEMENT OF SAMPLING PLOTS I TERRACE # ( SECTIONS I

Single Section

Figure 12. Methodof ogy and selected grass sampling sites at OLF terraces. Soil Samples Composi te samples of the top 5 cm of soil were taken every 4 weeks a1 ong predetermined lines across the width of each terrace, Figure 33. The compos- ltes consisted of 10 to 15 cores taken at random locations along each sampling l ine with three sampling lines bejng placed in each of the top three terraces (1 , 4, and 7) and one 1 ine being placed on each of the 1ower terraces (2, 3, 5, 6, 8, and 9), The variability in the number of cores per composite sample was due to the random nature of choosing the core sites. The lines were spaced as shown in Figure 13, Moisture contents were determined for each sample, includ- ing a control sample of a nearby off-terrace location, and nitrifying bacterial popul ations (Nitrosomas and ' Nitrobacterl were determined by the Most Probable Number method (Black, 1965). Other Measurements The Soil Science Department of North Carolina State Universi ty, in addition to providing data on groundwater analyses, also provided data on oxidation- reduction potentSals at various locations on the terraces at depths of 1.25 to 750 cm. Data for August 5 and August 19 were obtained on all terraces just prior to waste appl ication. Rainfall and temperature data were attained from the North Carolina State University Unit I I Research Farm Weather Station 1 ocated approximately 400 m from the over1 and flow site, MIDDLE

BOTTOM

TERRACE

OLF system. RESULTS AND DISCUSSION Water Mass Balance The establishment of a water mass balance followed the general formulation

Water Input (OLFi) = Water Losses where: Water Input = Flush water + dilution water * rainfall

Water Loss = Wastewater runoff + rainfall runoff + evapotrans-

Water Inputs Overland flow infl ow (OEF1" ) quantities were determined by averaging weekly flow-rate determination taken just before the water flowed into the gated ground level troughs of terraces 1, 4, and 7 and multiplying this flow rate by the avera e duration of loading and by the number of loadings in the study period. 9 Flow rates were determined via a graduated bucket and stop watch.)

OLFi volume = (Avg. flow rate) x (Avg. loadfng duration) x (number of 1oadings) Rainfall quantities were determined by adding the total rainfa3 4 during the study period and multiplyin this by the area sf the terrace(s) under consideration. Rainfall Volume = 9Rainfall) x (Area of terrace(s)), Water Losses As mentioned previously, V-shaped flumes, through which runoff passed at the bottom of each terrace, were cal ibrated to relate flow rate to height of flow through the flume, Measurements of flow heights were taken once every four weeks throughout the study period at specified time intervals, Measure- ments were taken in each V-shaped Plume at 90-minute intervals for the first thlrty minutes of runoff and at 20-minute intervals thereafter until runoff stopped. An average of the flow rates taken over the study period, determined from the height measurements, was determined for each time interval and this flow rate was multiplied by the appropriate time interval to atta9n an average flow volume through a particular flume. In this way each runoff volume for each time interval could be combined to form a hydrograph which represents an average runoff volume per 1 oading for a particular terrace for the study period. Multiplication of this volume, the area under the hydrograph, by the number of loadings for the study perjod yielded a total runoff volume. Rainfall runoff was determined us4 ng the Soi S Conservation Sew! ce method for determinlng the volume of runoff from small watersheds (Kent, 1973). Characterist-ics sf the terraces or terrace systerns used to determine appro- priated curve numbers were asslgned as designated In Table 12, Based on these characterf st?cs, vsl ume of rai nfal 1 runo-ff for each terrace or terrace pair, was caScula"cd for each rainfall event, These values were than summed to give the total volume of ~afnfal l runoff for the study period, TabTe 14,

Table 92, CHARACTERISTICS OF OLF TERRACES USED IN ESTIMATING RAINFALL RUNOFF VOLUME BY THE SCS METHOD FOR SMALL WATERSHEDS (Kent, 'I 973) - - Land use I Treatment I Anti cedent mojsture Curve csndl tion number

1I X 90 men t

I I II II II I I

I I Contoured 3 l II 88

If )I

II I I

Evapotranspiratjon (ET) was determined by the Thornthwaite Method (Palmer, 19581, Monthly ET values were derived Prom monthly normal temperatures and the corresponding heat indices for the study period, Table 13, Water losses by ET we= calculated by multiplying the total ET for the study period by the area under consi deratl on, Table 14. Sail water (percol atlon component) was em1 uated as the di fference between the water inputs and the water 1 osses. Sol 1 water -. Water lnputs - wastewater runoff - ~ailnfallrunoff - evapotransplratl on Water mass balances were determined for the three top terraces (1, 4, and 7) and for th~eesets of terraces (1 4- 2, 4 + 5, and 7 4- 8), Tables 14 and 151, Terraces 3, 6, and 9 were not included in the water mass balances due to the absence of runoff and/or the sporatic nature of runoff through some periods of the study, Thfs would make the determination sf runoff volume extremely diffi- eul t and Inaccurate. Table 13, ESTIMATED EVAPOTRANSPIRATION FOR OLF SYSTEM BY THE THORNf HWAITE METHOD (Palmer, 1958)

Pl ay June July August September

November December

Table 14, VOLUMETRIC WATER HASS BALANCE (TOTAL FOR STUDY PERIOD) FOR POULTRY MANURE SLURRY OLF SYSTEM

NS trogen Mass Balance Nitrogen Input

Determination of the total amount of nitrogen loaded onto the terrace fo7- 1 owed the formulation:

Ni trogen input = (Avg- Conc. sf Nitrogen in the Overland Flow Inflow) x (Total Vol. of Naste Slurry Dilution hater) 42 - -

Table 95, WATER MASS BALANCE PERCENTAGE - BASIS IN OLF SYSTEM FOR POULTRY MANURE

Water Inputs, % 1 Water 1 osses, % Fl ush Soil Total runoff water

100 5 3 2 0 100 18 39 100 39 32

100 2 4 3 3 % 00 4 3 41

100 14 5 9

The concentration of nitrogen referred to on the previous page Is the total nitrogen (9-N) which was comprised of TKN and NO3-N. It is recognized here that rainfall contains certain amounts of nltrogen, but the concentration is so small that this source of nf tssgen was assumed to be insignificant for thfs study (Schuman, 19741, (It was estimated that the njtrogen load from rainfall for the entire study period would be less than 0,l kgN for each terrace, 1 Nitrogen Losses There are several routes nitrogen can take in overland flow. The ~outes comprise loss of nltrogen through surface runoff, grass uptake, groundwater flow, soil sorption, ammonia vol ital ization, denitrification, and microbial assimilation, The same general formulation used in determining nltrogen inputs was used for determining nl" trogen losses by runoff and by groundwater, i.e,, average concen trati on times vol ume, The groundwater percolatfon concentration was the average of NO3-hi cancentra- %Ions at the 2,4 m depth (assuml'ng T-N = NO3-N at this depth), It is recognized that the total volume of percolatfon water may not pass through the 2,4 m level due to possible horizontal percolation above that depth; however, it is felt that the amount of nitrogen yemoved by soil water flow can be approxjmated by this method, Very few rainfa1 I runoff samples were actual ly taken; average TKN-N concentration were estimated to be equal to be 8 mg/R for each terrace, These flgures were estimated Prom rafnfall runoff data for the month of July from two runoff plots 1 ocated less than 1500 m from the terraces of this study (Overcash, 9975b1, These plots were irrigated weekly with wastes at rates of 670 and 1350 kgN/ha,/yr and the corresponding runoff concentrations were on the order of 1 to 1%mg/R, NO3-N concentration in the rainfall runoff was estimated to be approxjmately 1J2 that of the average NO3-N concentration in the wastewater runoff; i,e,, 3 mg NO3-N/R, Thus, T-N concentrations in rafnfal l runoff was estl- mated to be 8 mg/Ro It is recognized that this method entails some error; however, nitrogen losses through rainfall runoff are shown to constitute only a small percentage of total nitrogen lost, Table IS, Even doubling or trip1 ing this estimate would not yield nitrogen losses of significant quantities for any of the te~races,

Table 16, NITROGEN MASS BALANCE FOR OHF PRETREATMENT OF POUL'TRY MANURE SbllRRI ES

Ni trogen inputs, kg Terrace Flush a 1-i-2 4 4-f-5 7

7-1-8

Seven grass samples from each of the terraces, taken at 2 to 3 week intervals starting with the sixth week, were analyzed for nitrogen content and used as a basis for the estimating nitrogen uptake by the grass, Appendix A. Grass yields were determined as discussed in Section 111, Grass Samples, and nitrogen yields for each sample were determined by multiplying the total grass yleld of the terrace by the concentration of nltrogen in the samples, The nltrogen yields for the seven samples for each terrace were averaged to give a mean nitrogen yield per week. This number was then mu7 tip%fed by the number of weeks fn the study period (24.4) to estimate the total nitrogen yield for the study period for each terrace, Nitrogen losses through ammonia vol ati l ization, denftri fi cation, soil sorp- tjon, and microbial assimi 1 atisn constl tute the "remaining unaccounted-for category, " Accurate determination of these nltrogen l osses in this scale sys tem is extremely difficult if not impossible, Therefore, these nltrogen losses were determined as the difference between the nitrogen going on and the nitrogen exi ti ng vl'a the routes of waste~aterrunoff, rainfa7 1 runoff, soil -water fl ow and grass assimil ation. This aggregate of nitrogen removal pathways may, and in this study did, constitute a major source for nitrogen loss, Ammonia volatilization itself has heen shown to constitute a major loss of nf trogen when manure is spread over the soil, Percent losses of has been shown to reach values greater than 90 for the warmer mon period of several days (Porter, 1975, and Lauer, 1975) Overland XI ow, however, constl tutes a process whereby nitrogen losses are dete bed over a much shorter tlme span, Coupled with the fact that volatil$zatlon occurs in a9 kaline pH ranges wi th rapid rates occurring where the pH Is above 9.5 (loehr, l974), there are questions as to the extent of vo%atilimat9onIn overland flow, Doak (1952) has shown, however, that pH values adjacent to microsftes of the hydrolysis of urea can reach 9,2 even when %he pH of the surroundln ment is as low as 5,5, Though poultry manure does not contain urea, this concept exhibits how the pH of the soil as a whole may not reflect the pH of individual "mi crosi tes, '" As with the water mass balance, mass balances of nStrogen were determined for the three top terraces and the three combir;ations of two terraces; i,e,, $1, T(l32) T4, T(4+5), TA, and T(7+8). Table I6 presents the T-N mass balances for the study period, The unaccounted category constituted the major means for nitrogen removalo Table I6 indicates that a large portion of the nitrogen removal was through ammonla volatilization, soil so~ption,denitr5 ficati andlos rnicroblal assirnjlation, This was more so the case for T4, T(4+5), T7 and T(7+8) than for the lower loading rate used on T1 and T(7+2), Wang (1976) studied the application of poultry waste to laboratory soil profiles, He Pound from mass balances no losses in total nltrsgen (only conversion to ni trate) as the wastewater percolated through the sojl columns when the 9'n-e"tlal storage capabil ity was exhausted after the fa"ri;%eight weeks, With regard to this observation it was reasoned that not much soil complexing was included in the unaccounted-for losses after the flrst few weeksz It may be that the greater portion of nitrogen removal of this category is through ammonia vol atil lzation and denitriflcatf on, Table 16 also shows that grass uptake of nltrogen became more prominent with progression down the terrace systems, and runoff l osses become less prominent, This, of course, -is a sfmple but lmpo~tantsequence, In additjon, the quantity of nitrogen In the g~oundwaterpassfng through the 2,4 m depth was small compared to the total qua1 9ty of nitrogen app7 ied, whfle nltrogen removal through rainfall runoff was even less sfgnificant,

For the purpose of identification of runoff samples, the fa77owlng descrip- tlve system will be used, Each sample deslgnator will consist of three parts, as djscussed in Section 1x1, Wastewater boadfng Samples, The first part will descrfbe the terrace number from which the sample was taken; the second part w%%%describe the nTtrogen form; and the thtrd part will descr-ibe the type of sample whether channel , regul ar, or average, Channel refe~sto smpl es taken at quarter sections of channel flow as dfscussed ea~l%e~,and regular refers to samples taken Tn sections other than channel sections, Average refess to a weighted average of the channel and ~egularsaflples, In presenting the average concentratton at the end of a terrace for the entire study period, the followfng procedu~was used, The values designated as the average of channel and regular samples were added to values obtalned every fourth week In which no differentiatfon was made between regular and channel fl ow, These fou~th-week samples were taken at one-ha1 f-hour %Pterm% s durl'ng fl ow and were physlcal ly composi ted for al 1 sectfons of a terrace at each tlme interval and, thus, were average samples, A%%the average values were summed and dIvided by the total number of sample values to yield the average concentration over the experimental period, Thus, one has the foil possibili ties for each descriptive part for a sample deslgnatlon:

TI TMN CNL T 2 NH3 (amonia ni trogen) REG % 4 OGN (organic nltr % 5 NO3 (nl tmte nltrogen) T6 % 7 T8

n example, consider the designatjon T40GNCNL- T4 refers to the sample en f~omrunoff off the fourth terrace, 6GN des i trogen form and CNL refers to the sample belng taken in a quarter s e channel flow was sccurn ng, As previously establ lshed, the term "%eve%" was used to differentiate between the top, middle, and bottom terraces, Figure 9. Thus, the top level csnsjsted of TI, T4, and T7; the middle %eve%consisted of T2, T5, and 48; and bottom snsisted of TS, T6, and T9, It is important to remember that concentration ~eductionvalues far each level reflect changes Prom the initjal overland inflow concentration; thus, each level is a component or an additive of each succeeding level , Bas?c statl st! cal procedures were used to determine di Pferences between means for four modes of comparjson of ni tr~genremova? efficienees: (1) differences between channel and regul ar fl ow; (2) differences between samp4 es taken a% different times during a sampling event; (3) differences between terraces and terrace systems; and (4) differences with respect to distance of flow wl thin a terrace system. For each comparison the hypothests tested was that there was no difference between the two means under conslderatjon, All comparisons were made by the use of Student's t distribution (Steel, 79601, The confidence level for testing was set at 0,lO $or the t~m-ta!Ied testn Diiscussfsn %n thjs sectfon 3s 'lirnfted to the nftrogers foms TKN, EW3-N and OGNn NO3-N is not discussed as ft will be treated separately -in a later section (Sectfon IV, Nitrate In Runoff), From thfs standpoint it fs important to consider the discussfon in this section and that for NO3-M to obtaln total nitrogen, The concentration reduction of TKN in runoff, for example, doe account for nitrogen as nltrate, Hocreve~, the YYN concentratfon reduetfon for each terrace, especlal Iy at the top 1 eve1 , does approximate T-N concentmttsn reduction slnce the nitrate coneentratfsn fn the sunaff was low, Concentration Reductlon - Channel Versus Regular (Nonchannellzed) Flow Table 97 lists the terraces and parameters in which a significant d5ffer- ence was determined to exist between channel concent duction and regular concentration reduction, It is noted that the d to derive the means under comparison were the mean values sf the channel or regular samples taken over the sampling event, Treatanent of data in thls manner is discussed in Sectjon IV, Concentration Reduction VersIs Time During Loading Event, In only three of twenty-four cases (there was no runoff on T-3) was the significant differences ; T6TKNREG concent~atlon reductSon was sign$Pi cantly igher than that of TGTKNCNL; P7TKNREG concentratl on reduction was si gnf %S cantly higher th of T7TKNCNL; and TSOGNREG was sfgnificantly hlgher than that of TTOGNCNL. a1 9 other sample means there was no slgni Pi cant dl fference between coneentrati on seduction by channel flow and that of regular f4sw. The nl trogen removal mechanism was as effect?ve under channel flow as under regular f7 ow; that is, no slgnlficant dlfferences were Pound in the great majority of cases, In thfs channels were mfnor; and thus, extreme care Sn OLF site preparation nsidered c~ltjcal?n the construc%'l:on sf field-scale systems, Only major large channels should be avolded,

Table 17, COMPARISON OF CONCENTRATION REDUCTION MEANS BETWEEN CHANNEL AND REGULAR FLOW (ONLY S IGNI FI CANT COMPARISONSLISTED) OCCURRING IN OLF SYSTEM

* Slgniflcant at the 0,lO level ***Significant at the 0,0% level - Note: Comparisons were done under methods for unequal wari ances and unpaired sbservatlons (p. 81 , Steel, 1960) ; eonse- quently, the t values used for testtng for a desired level of sfgnificance were weighted averages based on values of the lnddvidual varPab1es under comparison,

Concentsatton Reduction Yersus Time During Loading Event Wi th any waste control system it is Important to know how the eTfl ciency of the system changes with time during an operating event, During every fourth sampl lng event runoff samples were taken at ha%f-hou~ intervals thus providing a basis for attalnfng a more representative sample and also psovidlng a means to re1 ate concentration reductd on to time wi thln a single 1 oading event. Durlng

Appendix B presents graphs of average concentration reductions of the various nitrogen forms (TKNAVG, NH3AVG, and OGNAVG) with respect to week during the study period. Discussion of concentration reduction w respect to week is presented under Regression Analysis, Section IV; %ions of changes with respect to time during the stu put in perspective concentration reducti~nsaveraged over period.

Table 18, COMPARISON OF PERCENT CONCENTMTION REDUCTION TO TIME DURING SAMPLING EVENT - OlF OF POULTRY

T1 OGNAVG 29.79 1-208 T20GNAVG 16.36 0,386

I I I *Significant at the 0.10 level Table 19. PERCENT TKN CONCENTRATION REDUCTION: MEAN AND STANDARD DEVIATION - OLF OF POULTRY MANURE

Most of the values of TKNAVG and OGNAVG concentration reduction decreased as the study duration increased. This is more so the case for T4, T5, 17, T8, ' and T9 than for TI and T2. (T6 has too few points to make general observations.) Table 22 presents the average value of the first three samples taken during the study (TKNAVG and OGNAVG) for each terrace as compare Table 20, PERCENT NH3-N CONCENTRATION REDUCTION: MEAN AND STANDARD DEVIATION - OLF OF POULTRY MANURE

Table 29. PERCENT OGN CONCENTRATION REDUCTION: MEAN AND STANDARD DEVIATION - OLF OF POULTRY MANURE

Terrace

Channel Me an Stand, devc Regular Mean Stand, devo Total Mean average Stand, dev.

the last three samples taken durlng the study, Also presented are percent change in concentration reduction based on these two averages, Values for NH3AVG concent~ationreduction showed no obvious trends of change with the; houever, values for the terraces In System B show a slight upward trend with time, It 9s re-emphasfzed that these are general izations presented for the reader's fnformatfon as a method for defiwfng the nature of the data and, consequently, the mean values and standard deviatfsns, Table 22 is a supplement to Appendix 5, and the reader ?s advised not to use 4t without reference to this appendi x, Concentration Reductl on Di Pferences Between Terraces Section IV, Concentration Reduction Versus Time During Loading Event, and Average Concentration Reduction for the Study Period, out1 fned evidence to sug- gest that for the great majority of cases there are no signlflcant diffe~ences Table 22, GENERALIZED CHANGE IN CONCENTRATION REDUCTION FROM FIRST TO LAST PART OF OkF STUDY

Parameter

I1 TMNAVG T2T MNAVG T4TKNAVG T5TKNAVG T 7%KNAVG T8TKNAVG T9TKNAVG TI OGNAVG T20GNAVG T40GNAVG T50GNAVG T 7OGNAVG T80GNAVG TSOGNAVG

* A = Average percent concentration reductlon approximating the first three weeks of study, 5 = Average percent of concentration reduction approximating the last three weeks of study, -A-B = Percent decl ine in concentrati on reductl on over study A perf od. between nitrogen removal efficiencies by channel flow versus regular flow or by time during the sampling event, With this established the following statisti- cal analyses were based on "average" concentrations. "Averagei' in this sense refers to average concentration over ttme during the samp4Sng event as we71 as the average sf the channel and regular concentratfons. Figures 14, 15, and 16 present TKNAVG, NH3AYG, and OGNAYG percent concentration reduction, respectively, Each dot represents the average concentration reduction for the desi gnated n?trogen form determined from a sfngl e (weekly) sampling event on the designated terrace, Thus, every sample of runoff analyzed for TKNAVG, NH3AVG, and OGNAVG is represented In these thee figures, Means and standard deviation are designated to illust~~ate,the somewhat large average deviation from the means, Direct comparison of concentratian reductions between and within terrace systems are made possible by these figures. TabTe 23 compares means of TKNAVG, NH3AVG, and OGNAVG concentration reduction between terrace systems; i,e,, the means of the top terraces (TI, T4,

Table 23. COMPARISON OF CONCENTRATION REDUCTION MEANS BETWEEN OLF TERRACE SYSTEMS RECEIVING POULTRY MANURE SLURRY

under con N Form D. F. t value . P T KNAVG 2 1 2,46** 2 1 9,99* 2 7 0.10 14 7,05*** 14 3.69*** 20 2.52"" 12 0,92

OGN AVG

* Significant at 0.10 level 11 ** I' 0.05 " * ** It " 0.01 "

&-be: Comparisons involving TKNAVG and OGNAVG were done under methods for unequal variances and unpaired observations (See note, Table 121, Comparisons involving NH3AVG were done under methods for equal war1 - ances and unpaired observations (p. 83 Steel, 1960),

Table 24. COMPARISON OF CONCENTRATION REDUCTION MEANS AT FLOW DISTANCES WITHIN AN OLF TERRACE SYSTEM

* Significant at the 0,10 level * * 11 " " 0.05 " *** I I II I1 O,O% " Yote: A1 I comparisons done under methods for unequal variances and unpaired ~I observations (Steel , 1960). In another sense it is important to consfder deviations brought about by variables interrelated with the aging of the system, In this particular study the variables of temperature and resfdence time were considered importanto Tem- perature in a field situation is related to time on a seasonal basl so The fluctuation of temperature is important In relatfon to fts effect on data variance, especially .-in cases where chemical and blochemica1 reactions are of importance as in thls study. It is we17 documented that reactlon rates general 4y fncrease with increasi ng temperature, Variatl ons in reaction rate as a function of temperature can be represented, in many cases, by the Art-henius equatjon, where Ag Is the Arrhenius fr-equency; Ea is the activation energy; R is the uni- nt; and % is the absolute temperatuse (Weber, /972), (Though this equation Is beyond the scope of this study, it does serve to exhl bi t the importance of temperature sn reactSon processes, 1 idence time--that is the time the water sp n the terrace--is related to the of the system in that with the ng of t"rwe, at le for the ffrst s 1 weeks, the soil becomes more ted thus allowing n and, consequently, the effect of different time periods for reac- r processes tea take place (Weber, 197Z), The relationshjp IS the residence time ailable for a react3on or process to take place, the further it will go toward mpletfon, Resjdence t me js also inversely related to the velocity of- Plow wh h in this sense incorp rates the effects of washing rt of partlcul a uspended matter,

Deviation due to resSdence tlme differences Is Immediately 7%1 ustrated when comparing the variance of the concentration reductions for the various levels of In every terr ce system and for each nitrogen form the variance substantially w th succeeding terraces or residence t5me in ObF, and 29, It Is suggested that these dl'fferences in variance Ily to residence time since other variables such as temperature, oncentration and rainfall are similar for each level with3n a terrace The variable of ging or amount of waste reaching the salT e of common valu with each level within a terrace system, difficult to draw a direct relationship between thls variable and th variance between the level sf t~eatment, On the one hand, the top-level terraces are more aged; but as pointed out prevjously, each level is a component of each succeeding level, Thus, variation due to aging of an upper terrace Is reflected in the variation of a lower terrace, It is suggested that the effect of a lower terrace relata've to an upper terrace is to exha'bit a greater rate of variation since it is less aged, Thus, the overall effect of aging variation, it would be hypothesized, 5s that the accumulat%on of var increases with each succeeding level. On the other hand, however, it may be hypothesized that a lower terr ce wl th 1 ower volumes of PI ow and Sower concentrations may reach a steady st te quickly, thus having the overall effect of . decreasing variation (note the differences in variation fn Tables 19, 20, and 21 between the terrace systems with reference to the differences in loading parameters 1. Other variables considered as causing deviations %n concentration reduction were initial concentratfans of the nitrogen forms PIowdng onto the terrace and rainfal 1. The interest in ini tial concentration relates basically to the law of mass action which states that the rate of an elementary homogeneous cheml cal reaction is directly proporttonal to the product of the concentrations of the reacting species (Weber, 1972). The reactions which are important In the removal of nttrogen 9n thls study may not be elementary or homogeneous, but the law, nonetheless, provides a basls for the lnterest in in5 tial concentration, Rainfall, on the other hand, may induce deviations that are conceptua?Sy complex, Washing the terraces and moisture relationships can be considered to affect concentrations of the nitrogen forms In runoff, The washlng effect relates to the actual physical transport of waste components and also to the transport of soluble species, ammonium [NH&+)and nitrate (NO3-), The moisture relationships relate basically to the physical phenomenon of degree of saturation (and thus residence tjme) and to bi 01 ogical phenomena associated with the nature of environmental condi tions for selective microbial growth, Thus, the concentration reduction of nitrogeneous specjes was hypothesized to depend on the independent variables of system age, ambient temperature, residence time, or distance of ObF, inftlal concentration (ObFi), and rainfall amount, Statlstica7 analysis by means of multiple regressjon was used to describe the re1 ationship between these dependent variables and the in ent varjables, In this way the significance of using v3gue5 of fndepe variables to predict values of dependent variables can b establ ished, Appendix B contains graphs of the concentration reductions of the various nitrogen forms plotted against the number of weeks sf operation, It is jmpor- tant to keep in mind that the graphs do not yepresent the concentration reductions as simple functions of time alone, since temperature and some lnfluent concentration changes occurt-ed, The regression sect4 sn Inte~pr $5 these effects,

Dependent variables wi9 9 retain the same f dentifisation as previously established; however, runoff sampl& from terraces %6 and %9 will no included in the analyses due to the sporatlc nature of the runoff. Llsted be1 ow are the independent variables with descriptjve comments: TIME: The aging variable, expressed as the number of weeks fsom the beginning of the study, RESIDENT TIME: Time required for the wastewater to flow across the terrace, measured in mlnutes from the tlme when load- jng began at the top terraces till the time runoff began for the terrace under considerati on, TEMPERATURE: Average of the low and high temperature for the day sampling took place measured in "C. BOX CONCENTRATION: Ini tia1 concentrat? on of the ni trogen component in the liquid before OLF application, mg/R(OLFi), RAINFALL: Total rainfall measured in centdmeters for the day of sampl ing plus the rainfall from the previous t~odays. Table 25 presents simple descriptive statist4 cs of the jndependent war4 ables in this study. Regression Results

Tables 26, 27, and 28 present data from the regression analysis for concentration reductions of TKNAVG, NH3AVG, and OGMAVG, respeetive%y, The 5 val ues represent the partial regression coeffi cient assocfated with the par- ticul ar independent variables under consideration for the regression % ine and the intercept, I, Is the point where the line meets or crosses the ordinate, Table 25, SIMPLE STATISTICS OF INDEPENDENT VARIABLES FOR POULTRY MANURE OBF STUDY

Standard devl ation

Tine !,2 (weeks)

RESIDENT TIME (ms'n)

TEMPERATURE ("C)

where Y is the dependent variable, Bj js the pa~tlalregression csefficie~tfor independent varjable Xi, and I Is the Intercepto

6 0

ehe depletion of NH3 (through ammonia vol ata"3 a" zation and bl ochemi cal seactl ons sf nit~rifyingbacterfa), The fact that there is no evidence that NH3AVG concentration reduction changes significant1y with ta"me lends credi t to the differences in means previously determined significant, Section IV, Csncent ration Reduct i or: Df ffereraces Between Terraces, and Tab1 e 23.

For T4NH3WVG cmcentratIon reduction, TIME, RESIDENCE TIME, AND BOX CON- N are shown to account for 54 percent of the total regres this figure isn't arge, it does merit consideration) it Is seen, by far Is the most %mortant variable to the three that nificant in p~e- dicting the yd4 ue $ T4NH3 concentration reduction, ositl ve, as are a7 1 of %he B values, It shows an increase in NH3AVG r efffclency with increasing time, Thls effect, f t is hypothesized, fs due to the large signifi - cant myatlve B value assoc=iated wf th TIME and T4BGNAVG concentrat% as shall be discussed in the Following discussjsn; thus, the NH3 c~eation process is greatly lirnlted with passage sf time during the study,

The regressi on analyses for the concentration reductf on of OGNAVG ylel ded TIME and BOX CONCENTWTLBN as significant in a91 but one case, T20GNAVG (Table 281, All 5 values associated with TIME are negative fndicating a decline in efflsiency with time and B values for the regression of T40GNAVG and TYOGNAVG on tlme are reflected in the B values of the independent variable for T4TKNAVG and T7TKNAVG; thus, the relationship between OGN and TKN removal efficiency is exhibited (OGN being a part of TKN), This relationship is important in that TKN must not be regarded as an entity apart from OGN and NH3, Changes or characteristics of TMN values are reflections of OGN and NH3 values, Section IV, Regression on NH3AVG Concentration Reducti on, points out that the independent variables are not useful (except for T4NH3AVG) in predicting values of NH3AVG concentration reduction, Coupled with the ev4dence that NH3AVG concentration reduction showed no obvious trends of change with time during the study period, it is clear that the changes In OGN values were the major controlling force in producing changes in XKN values. The effect of the NH3 values was to temper the degree of change In TKN values relatfve to changes in values of OGN, since the NH3 values for the most part showed no trends In changing signfficantly with time or w-ith respect to the other independent variables, There was no slgnl fl cant regress3 on of T20GNAVG concentration reduction on TIME, Thls lends @red$t to the previous%y establ lshed signiff cant differences between the means of T20GNAVG versus T50GNAVG, and T8OGNAVG (which showed negative significant B values with respect to tlme). Rhalues, though not l arge, do lend additional evldence to the hypothesis that OGNAYG concentratlon reductions can be estimated knowing B values for TIME and BOX CBNCENTBAT%ONo

A mu1 tiple regression on OGNAVG concentration reductions for the last half of the study (93 weeks) ware run for each terrace uslng the same independent vari ables as previ ous%ydesignated significant for the whole period, Table 29, The regression on tIme show a definite change from the data of Table 28, In only one case dld a parameter exhlbit a significant reg~essionon TIME, XIOGNAVG the B value belng posd ti ve) , Regress-ions on T4OGNAVG, T50GNAVG, Table 29, REGRESSION FOR OGNAVG CO CENTRATION REDUCTION FOR LAST HA&% OF

-.---rT-----w------=.%.---" --- "*"=-- --sr=r,---- rcar - line Box canceta- ji Interce B

respect %a TIME weye not signjficant In rraee systems (B & G ad reached a ste % Y4OGNAVG and T7OGN d$stance), -2,4 percent and -7,22 percent, respectively , jndf- the steady state there was 1ittle concentration reduction of treatment capabf l i tde of these terraces wl th respect to osganjc ni trsgen eoncentratj on reduc y this period, had dlrninished comple val of total Kjejdahl nl n far these te~races(4 & 7) by this was almost exclusively by ammonia pathways, Slnce NH3AVG concentrati o tion did not change sign3flsantly with tfme for the entlre study peria In seen how a regression of TKNAVG concentration reducllon last half (as well as the first half) would be a reflectjon of the reqression of OGNAVG concentration reduction WEEK, Consequently, a mu1 ipl e ;egress ion on TKNAMG was not run for this gerlod since it would prow de %i Info~matlonnot 1 ready avai %ablefrom the OGNAVG regress?o (See Section IV, Regress? on on OGMAMG Concentration Reduction, for diseusslon of OGN values, ) The means of OGNAVG concentratlon reduction for 55 and T8, the middle levels of terrace Systems €3 and C, respec-tlvely, were posftive (21,4 and 48,33, soespectfveSy). Coupled with the Pact that tjme showed no szignlflearat regresston on OGNAMG at 30 m (T5 and %%I, $t is hypothesized that these systems (5 and C) at the middle level had represented a steady state b m-iddle of the study, There was a c on these terraces, The regressfsn of time on TlOGNAVG concentration reduction was signifi - cant (O,O5) and posl ti ve, This f ndi cates an lncrease

Only two autstrophic genera are generally conside~edprominent In ssil nl %r! Pi cation, LV~-tmaomanaasand lVitro.bactur, The poperl a%$on sf these two genera are frequently quite small and many soqTs, garticwla~lyasid soils, have fewer than 100 viable cells per gram, As a rule, numbers Sn excess of 105 per gram are rare 9 n unfertl 1 lred so?i . Hsweve~,when the sol l ? s treated w? th manure or an arnmonla fei~tilizer, the numbers may reach values -R"n excess of l OGand, o'zcasl onal 'ly , 1Ohe')ll s per gram 4 Bastho? sinew, 7 965 1. Two techniques were used in this study to establtsh the evidence of and the degme sf n1trificata"on: (I 1 deterrnjnatfon af Nitrosmmas and flit~~baotepr populatjsns, and (2) the existence of NO3 In runoff, g;~oundwater,and grass tfssue, In addi tasn, the oxidation-~edustfsn status sf the ssil is discussed with respect to environmental condf ttons favorable for njtriffcatlon,

Appendfx C eonta9ns graphs of micrsblal papu%at?onsversus time for the study period- In ew~ycase the popu%a$!ons reached a maximum value during the Pipsf 2 to 4 weeks of the study; then, deweased drastfcalry thereafter, Numbers Q the lo6 and lo7 range were determined fo~the upper terraces and 10-0 lob POP the louer terraces during this maximum pe~fsd, In almost every case the pspu%at9swsreached %wo add?tganal peaks, but st Is questioned whether the deteminatlsns on August 20 and October 35 mfght csnta?n some p~ocedural errorc (In one case, soil samples were mistakenly f~ozenfor 24 hours, 1 In the early stages the lVi~a?obaoteir,g~eatly sutnumbe;~ed the Pi txwst;mmas whereas in the latter stages the opposl%e was the case, Th is may haw been a result of the relative availab~lityof an energy source during these two perjods. ArnmonSum and n9trite salts were both ava?lable qn the earlier when the sol 1 was less moist and, therefore, more subject to ae~atssn(moisture contents were determined for sol%samples), On the other hand, the so59, being saturated a great part of the time, after the irst few weeks would inhibit the production of nitrite to a much greater degree than It w ul d amrnonl um during this period, The nl trite that is produced can undergo chemical denitrification which is cosnmon in acid sol'ls, and/os biolog-ical denitri"6i by robjc bacteria, (The sot l pH f P an adjacent off-terrace site Thus, the flizrosomonas bact ria had a more readily avail - rce than the Ni&ydoabaeter, Another considerati on Is the inhibit- he large applications of nltrogen on W'itrobwter growth (Roth- wl % , 1969, and Stajonovi c, TX81, The nature of the population data does not lend itself to stdtistlcal lysfs, but comparisons are In o~der, Terrace 4 appears to have supported lf"yng bacter al popu%a%%onsf any of the terraces, Appendix C. be Ijttle dl ference between Terrace % and Terrace 7, There i fferences in the numbers between Terraces 2, 5, and 8; and in ul ati ons decreased with each succeedf ng 1ev f wtkin each ter- rdce system, (Pessi ble reasons for these differences wsl? be discussed 'n Section IV, Nitrate In Runoff, 1 The populations determfned for control fie1 samples adjacent to the terraces (see graph) further enhances the large number determined present during the first part of the study on the terraces, Thus, evidence of nitrification 1s available, especially for the first few weeks sf the study period, Nitrate in Runoff Table 30 presents means of NO3--N concentrations in the runoff from each of the terraces, Appendix D shows graphs of NO3-[( concentration plotted against tlme during the study, As can be seen, and would be expected, the value of the data points reflect the eneral change in the nitrifying bacteria populations with time (see Appendix C 3 . The high NO3-M values at the first of the study quickly subslded to much lower concentrations after only 4 to '7 weeks, The high values corresponded for the most part to the high Nitrobac&ar populations at the Pi rst of the study, Appendix C, (A skewed data set resulted fmm thfs general trend in each terrace; thus, determination of differences between means by statlstjcal methods were not attempted nor were regressjon enilyses used,) This trend, it Is suggested, fs caused by the onset of anaerobic conditions due to saturation of the soil as water inputs exceeded drainage capac%ty, Relative to this phenomenon it Is pointed out that Terrace 6 shows a high NQ3-N concentration mean; however, this may not reflect an inherent capability of Terrace 6 to produce more nl trate, but may only reflect the more amenable ms-isture status of the terrace due to its stage of agjng" The data show terrace System 5 most productive as a whole in the formation of nitrate (though $1 produced the hdghest concentration of any sjngle terrace). This, acjatn, %'sIn accordance (considerjng the terrace systems as awhale) with the relative numbers of nitrifying bacterial popul at! on, Reasons for- differ- ences between nitrate production by the terraces can be discussed under the consi derations of substrate avail abi 1 i ty and oxygen status, Obv'ously , terrace Systems 5 and C are sImi%arin the amount of substrate available; however, System B has a more conducive oxygen status due to its frequency of loading (every other day) and longer rest perf ods, It is difficult to compare the oxygen status of A to B since there is a great diffe~encebetween their hydraul lc loads, Though A is loaded every day, it may be that due to the lower Table 30. NO3-N CONCENTRATION IN OLF RUNOFF: MEAN AND STANDARD DEVIATION

hydraulic load, the top few centimeters of the soil may draln faster thus providing for aerobic conditions between loadings. However, A fs loaded with less substrate than B. Terrace System A, on the other hand, is more nitrate productive than C, probably due to C's less favorable oxygen status. (This method of differentiating between the terraces ' nitrate productivity is certainly an over- simplification but provides a practical means for interpretatjon of results.)

The same methods as used for TKNj ' NH3-id,, and OGN (Secti on IV, Concentra- tion Reduction Versus Time During Loading Event, Table 18) were used for nitrate to test for significant differences in concentration with respect to tlme during the sampling event, In only one case was there a significant difference at the 0,10 level ; on Terrace 2 between the first and middle concentrations and between the first and last concentrations, No significant differences were determined between the middle and last concentration on this terrace.

A1 though there were no significant differences determined at the statisti - cal level established, there seemed to be a definite trend in 4 of the 6 terraces considered for the concentrations to decrease with increase in time during the sampling event. As a matter of interest, for comparison purposes the United States Public Health Service sets the limit of nitrate-nitrogen in drinking water at 10 mg NO3--NIL (Phelan, 1975). The data of mean values presented in Table 30 present only one terrace with values exceeding this 7 imit (Terrace 6) ; however, runoff Prom a91 terraces during the first part of the study dld exceed this value as can be determined from the graphs of nitrate versus time (Appendix D). Nitrate in Soi 1 -Water

Table 31 presents the mean concentrations of NO3-N in the soil-water at the 0.3 m, 0,9 m, 1.5 m, and 2,4 m depth for the study period. It is difficult to draw conclusions about the change in concentration with depth for the individual terraces since the data varied and seemed to fo79sw no general trends, However, the concentration at the 0.3 m depth was 1ower than the concentrations at the other depths, except for Terrace 3, Many factors undoubtedly are fnvolved in this trend, one being plant uptake of nitrate in the root zone, Another factor, it is suggested, is the more amenable environment of the upper horizons to denitrifying bacteria due to the avai 1abi 1 ity of substrate and peri odic saturated conditions, Coupled with the fact that soil-water samples were collected over a 24-hour period, it is apparent how nitrate could be reduced in concentrations at the 0.3 rn depth,

Table 31 also indjcates that Terrace B is the largest contributor of nitrate to soil-water with C the next largest, Table 32 also exhibits this relationship; but more Importantly, it reflects the trend of decline in nitrification with time, This substantiates these trends as discussed in previous secti ons,

Table 31. MEAN NO3-N CONCENTRATION IN SOIL-WATER BENEATH OLF SITE (mg/L) -. Terrace Terrace mean

1 7.45

2 2,25

6 7

Depth mean

Table 32. MEAN NO3--N SOIL-WATER CONCENTRATION BENEATH OLF TERRACE SYSTEM WITH TIME (mg/R)

Redox Measurement

Using a chemical substance as a mlcrobla7 energy source always involves an oxidation-reduction reaction, The bas1s of 0x1 dation-reduetlon reactions is electron transfer where the tendency of' a compound to glve u (act as energy source) Is expressed as its sxidatisn-reduction (Brock, 19741, This characteristic, commonly termed redsx p measured electrical ly (in volts) in reference to a standard its numerical value is directly proportional to the eempoundbs capacity to donate electrons; i,e,, act as an energy soume, en disappearance occurs between 500 to 350 milllvolts Eh and nitrate ance occurs between 350 and 100 rnlTl1volts Eh In a sediment water sys tem (Keeney , 1973). Initi al dl sappearance of oxygen In water1 ogged soi I s has been equated with redox readings of 600 to 500 mi1% ivolts Eh and nitrate reduction has been estimated to begin at the same values (Aomine, 19621, >=readings for this study (Table 34) wer n two separate occasions ferent so51 depths, It is sf interest $0 note thar the dg the tjme when the declinfng of nitrfficati'sn was becomlng n ced by the data from microbial populations and nitrate In values themselves, for the most part, fall wit n the range where the djs- appearance of oxygen occurs and where nitrate duction begins, Thus, it appears that optimum environmental condl tlons did not exist for njtr%fication,

General relationshfps show the redox values increasing wlth each success- ive level in the terrace system, This, of course, is a generalization and varies with the individual terraces and/or system.

The influent concentrations of manure s%urry plus dilutlon water, Table 9, were used to cal cu7 ate concentrati on reductions, Mass reductions were obtained by adjusting for water losses,

The three terrace systems after 15 m and 30 m of flow dlstance evidenced sa"mi9ar losses of COD, t-PO,-P, TOC, and C% (Table 351, On a mass ba%ance basis, the t-PO4-P and COD were in agreement with results for the more concentrated raw domestic waste effluent fr~mObF systems, TabTe 2, Table 34, REDOX READINGS WITH DEPTH ON OLF TERRACES JUST PRIOR TO NORMAL WASTEWATER APPLICATION (Eh)

Depth, em -Terrace - Date 1 8/5/75 2 3 4

6 a

8/19/75 Table 35. CONCENTRATION-BASED AND MASS REMOVALS FOR OLF PRETREATMENT OF POULTRY MANURE, INFLUENT SPECIFIED IN TABLE 9 Was tewatg B 37 m

COD 76,8

0-N 37,l 75,7

56,O

48,4

65,O

-959.4

% Mass Loss f Dm Was tewat- A Parameter

COD

"Estimated values of t-PO4-P for 1st part of study were used fn determination of % loss, SECTION V

FARM SCALE APPLICATION OF OkF PRETREATMENT Producer Objectives The use of an ObF pretreatment for pouStry manure (or for such wastes as swine, beef, or dairy manure) is based on the producer objective of minimizing the cost or 'I and area needed for waste management, Th LF 1s a pretreatment which removes nitrogen thereby reduclng the land limit-ing constituent in animal waste, Partial recovery of the ni trogen in the grass cower crop is obtained, but the predominant objective is nitrogen dissipation, OLF pretreatment may also all ow the producer to utilize farm areas in which the soil type is somewhat poorly to poorly drained, These areas have inherent l lm-i tations for other agricultural uses; hence, incorporation in$ sati sfactory waste management system woul d be desi rab'I e. In add%t.j on to the objective of nitrogen reduction and increased margf nal land use, ObF can serve In conjunction with a flush system for waste cleaning. Not all pretreatment processes are compatible with high-wate~use flush systems, Thus, the ease and I abor-saving advantages of Pl ush systems for poultry or other animal manures can be realized by the producer,

Producer System Requi rements Animal waste Is characteristically a concentrated slurry; and thus, to be used In an OLF mode, dilution water must be added, A flush system a1 1 ows the add1 tion of water as we1 1 as substitution for labor or mechanical devices in manure cleaning of animal production units, Therefore, most OLF systems must be coupled with a flush or flush-recycle system, Fo%lowinga flush waste transport system, a sloped area of moderate to poorly drained soils is needed for ObF pretreatment, SS opes of 2-8 percent are acceptable, This area should be smoothed to remove large channels and then prepared with a stand of Reed Canary, redtop, and fescue grass, By means of dlversions or natural topography, the OLF effluent must be directed Lo a sump or retention pond, A sump would be used if direct land applicat=ion on a daily or weekly basis Is desired, A retention pond would be necessary if land appl i- cation were to occur in conjunction with crop needs, approximately four times per year, The lagoon or sump will allow recycle of liquid for manure flushing. Finally, a terminal land receiver system will be needed for the ObF effluent, Such a recelver is reduced in area and, correspondingly, in irrigation equipment by the presence sf the OLF system, The design size for the terminal receiver is control led by the nl trogen content and the percent reductlon of nitrogen occurring in the ObF system,

Producer System Design In demonstratjng the use of ObF for animal wastes, a case study for 10,000 caged layers was chosen. The major waste constituents used in design calcul atlons was ndtrogen, the land-$ iml ting constituent "in animal waste for the moi sture-excess Southeast, Transfer sf system design to other animal types one based on nl trsgen equf val ents f n the waste load , For a 10,00Q c ged liiye~mlt, the nitrogen waste load is abo~t2 day, Direct 1 and a p7lcatjsn of this manure at the recommended rates jhajyr would require 24 ha, of grassed pasture area, Such a system repre- nts the maximum land as a and best potential $or ~ecycl7ng to a cropping stem, tloweverg many pa8 Itry prodi~cersdo not own 24 ha, pep 10,800 b-irds or ccess to such land ar as, Fop thes presdeicers pret:-eatment -a" s bce nitheogen levels =i i lhb9e land a{-eas, In order to use ObF as a pretreatment prsces , 9"t is assum psoducel* has a flush system or that adaptations f P such a SJS~ Recommendat7 ons f %tons are current1 fsrmul ated (Barker, 1976), Following nd purnpjng or geav9I&y i%o~ s.y%te e BLF system, If a sump and pump red bec3use sf the presence of feathers and eg ssure, gated p7 ground-level appl icatlon system 7ng large or4fj poultry wastewater is recommend on to the OLE system, This method of distsibut e use of large orlfice low- pressure trash pump can be used to transport the waste to the OLF site, butf~soa~the present raesearch experience %em cannot be used directly for land application, The pr~nc~pal t Plushlng on a once-per-day basls occurs over a '-2 minute perio slower I iquId appl ication pate for such wastewater volume OLF site to prevent erosion or pulse washes, Durlng the settling occu~sif no feclrculation fs provided, However, the authors believe that a more complex system of frequent flushing and sump attenuatjon can be designed to a1 %ow direct appl $cation of flushed manure to an OLF site under gravity flow condjt~ons, Such a system would be very attractive in terms of ~edueedelectrf c operational costs, WSth respect to the so71 type required for a suecessf~lanimal waste pretreatment OLF system no definite recommendations are ava9 lablea The early can- nf ng waste systems were on extrern ly impermeabse gal aciated, calcareous clay soils, Continued literature reference is made t the need for l ow-permeabi 9 i ty soSJs (less than 0,15 cmphr); however, the existl~gpoultry research system is on a well-drained soil (with pemeabllltjes in the range sf 1 5 to 5,O cm/hr). It would appear that soil seallng wlth a microbfal mat could alter the jn=it%al soil properties and allow a larger range of soil types to be utilized, From the Slmlted Information available, 5% is recommended that fa$r to poor-%y dralned soil types be chosen fo~OLF, More research js needed to evaluate the capabillt ies of other broad c~asslficaclonssf so11 types for OkF systems, Dur%ngwaste handling and transport, little nitrogen Toss occurs and essentially 20 kg Njday is the input to the OLF system, Two w~erlandflow dtstances (15 m and 30 m) wjll be considered as representing the different Bevels of nitrogen removals, Nitrogen fnput in this research project was 3000-6800 kg N/ha,g'yr based on a 15 m flow dSstarace and for. c~nservatjve estlmate 3000 kg N]ha,/y~ Is chosen as the land-app flow distance approximately 1600 m of da stributisw ipe would be nee That Is, a single terrace or multiple terraces amounting to 4600 m in length would be neededn The total ObF land area would be 2,43 ha, Terrace(s) would cons~stof the wastewater dlstrlbutlon system and a cot lection ditch at the end of the 15 m distance fos the OLF effiuent, Mass reductions of nitrogen would be 60-70 percent of the Influent, Table 46, or a waste load of 6-8 kg M&day as OD effluentA

Greater nltrogen removals would result by increasing the flow distance to 30 m and maintain~nga constant waste load, Such a system would s%iI%require 1600 of terrace width and at 30 m in length would require an area of 4-9 ha. The nltragen removal would increase to 80-90 percent, Table 3 OLH effluent would be approximately 2-4 kg N/day, This i~cre 15 m to 30 m Is not as great as that from 0 rn -15 rn but does represent a sub- s tantidl ly lower amount of nitrogen Prom the OLF pretreatment,

Bi reet 1 and appl i catl on fol 1 owing pretreatment csu7 d be accsmpl i s oviding mlnfmal storage for non-irrigation periods of 5-2 weeks, Such a Iding basin would depend on the flush water input but ~ou%dgenerally be sma91, Land areas sequlred for the effluent from the 15 m and 30 m flow distance systems, based on 300 kg N%ha,jy~,would be 7,5-10 ha, and 2,s-5 ha., respectively, The combined OLF and tes'mlnal land receiver areas for the I5 m Song and 30 m long systems would be 10-12,s ha, and 7,5-70 ha,, respect9we%y, which 1s about 39-52 percent of the land area for direct land appl ication of poul try manure, Instead of weekly land applacation of OLF effluent, producers may opt for a 4-times-per-year cycle of irrlgatjon of OkF effluent. Such a system would better match the periods in which a crop could utfllze the waste constituents and would reduce the labor for wastewater Irri gation to a few tsrnes edch year, A retentlon pond providing 3-5 months storage for poultry manure, jni tial d%lutfonwater, net rainfall excess, and recommended free board would allow four months of OLF operatfon without irrigation to nea~byareas, The poultry manure volume would be approximately 270 mhsf volume, The needed dilution water was estimated to be 25 tjmes the manure Input, The 25:l dl7ut3on water represents 6800 m4 of volume for a total wastewater volume of 7000 m" Allow- Tng 0,20 m sainfal1 excess and 0,s m freeboard, the total retention pond or lagoon volume js about 9,5000 m3 and would cast about $7,800 to construct, The lagoon would serve as the source for recycling water to flush the caged layer house, Wlth the average retentlon time of 45 days the lagoon would provide additional nf trogen loss through ammonia vo%at7 1 izatf on (Over- cash, 19761, Based on the TKN effluent from a psult'a~ylagoon study of loading mtes (Overcash, 19741, i t was estimated that a 60-70 percent seduction in TKN would occur fn a residence time of 45 days (one-half of the 3-month input period), Applying this reduction to the 15 m and 30 m system results in an effluent for land application equivalent to 2,l-2,8 kg Nfd and OJ-%,4kg N/d, respectively, The land area for a terminal receiver of this effluent over an annual cycle would be 2,6-3,4 ha, and 0.85-1,7 ha, for the 15 m and 30 m ObF systems, respectively, For the t~talsystem of Plush, OLF, 3-month recycle pond, and tem!nal land application the required waste management 1 and area would be 5-6 ha, for the 95 m system and 5-6,5 ha, for the 30 m system, In relation to direct Band application of the caged layer manure, this pretreat- rnent-land appl?cation system requires about 20 percent of the land area, In cenclus-ion, OLF can serve to substantially reduce the total land area for waste management as summarized In Table 36, Based on perfomance of this experimental research study, OLF reduces land needs by 50-70 percent and when

LIST OF REFERENCES Abernathy, A, R. A demonstration project using overland flow for treat- ing domestic wastewater In South Carolina. Research Proposal to South Carolina Dept, of Health & Environmental Control, C9 emson Unjv,, Dept, of Env, Systems Eng. 1976. American Pub7 ic Health Association, 197'1 . Standaind Methods for the Exam nation of Water and Wastewater, Amerlcan Water Wo~ksAssoc,, and Water Pol 1 ution Control Federation, pp, 1-874, Aomine, S. 1962, A Review of Research on Redsx Potentials of Paddy Soi in Japan, Soil Science 94: 6-1 3. Aull, L. E. Unpublished data, Soil Scjence Department, North Carolina State Uni versi ty , 1975, Bdr%ho%omew,W, W., and F, F. Clark, editors, 1965, Soil N~trogen, American Society sf Agronomy, No, 10: 309-335.

Bendixen, T. W., R, D, Hill, F. T, DuByne, and G, G. Wobeck. Cannery Waste Treatment by Spray I rrigation-Runoff, JWPC 4%(3) :385-39%, 1969. Black, 6. A,, editor, 1965, Methods of Soil Analysis, Part 2. American Society of Agronomy, Inc, , Madison, Wisconsin: pp, 1467-9482. Brock, T. D. , 1974. Biology of Mlcroorganlsms. Prentice-Hall , Englewood Cliffs, N. J,

Carl son, C, A., P, Go Hung, and To B. Delaney, Jr. Overland Flow Treat- ment of Wastewater, U.S. Army Engineer Waterways Experiment Station, Vicksburg, Miss, Mlscel laneous Paper Y-7'4-3, U,S, Army Corps of Engl- neers. Aug. 4974. 107' pp. Covfl, D. M, Overland Flow Pretreatment of Poultry Manure, North Caro- lina State University, M,S, Thesis, 1976, Doak, B, W. 1952, Some Chemical Changes in the Nitrogenous Constituents sf Urlne When Voided on Pasture, Journal of Agricultural Sc$ence, 42: 162-971 ,

Gray, T. R, Go and S. T. Williams. l979. Soil Micro-Organisms, Ollver and Boyd, Edinburgh, England. pp, 1-196. Hoeppel, R. E., P. G, Hunt, and T. B. Delaney. 197'4. Wastewater Treat- ment on Soils of Low Pemeabil i ty. U, S. Army Engjneer Waterways Experi- ment Station, Vicksburg, Miss, Miscel laneous Paper Y-74-2, Humenik, F, J., R, E. Sneed, Ma R, Overcash, J, C. Barker and Go Do Wetheri 11, Total Waste Management for a barge Swine Producti on Facl%i ty. In Proc. of the 3rd Int'l Symp. on Livestock Wastes. St. Joseph, Mich, Amer, Soc, Agr, Eng, PROC - 275, April 1975, pp, 68-l7%, Humenik, F. J., et a!. , 1975a. Transformations of Swine Wastewater in Laboratory Soi l Prbfi l es. Transactions of the American Society of Agri - cultural Engineers, Vol , 18: pp, 1130-11350 Keeney, D, R, 1973, The Nitrogen Cycle ?n Sediment Water Systems dour. of Envi ~snmentalQua1 l; ty 2 : 15-29,

Kenz, KO M, 1973, A Method for Estimating Volume and Rate af Runoff in Smal I Watersheds, Ssi l Conservation Service, U.S. Dept- of Agriculture, Pub1 imtfsn No, SCS-KP-149, Kirby, C, F, Sewage Treatment Farms, Ci wiS Engineering, Me1 bourne Uni- versity, 16 pp, 7970,

E, To Lakeland's Gmrs Filter Removes M st BOD, Suspended % Enough Nutrients, Overflow, May 8-70, 1972,

Loehr, R, C, 1974, AgrlcuS tural. Waste Management Problems, and Approaches, Academic P~ess,New Yo& and London, p, 362, Lowe, R, H, and J, L, Hamilton, 1967, Rapid Method for Determination sf Nltsate in Plant and So-il Extracts, Agricu'%ture& Foo Cheml stry 15 (2) : 3%9-J6l An Eva7 uati n of Cannery Waste Dl sposal by Over1 and F%ow Spray %m%gation,Campbell Soup Company, Parjs PI ant, Pub1 ications in Climatology XMS1(2):1-33, $969, Mepr, E, A, and R, M, Butler, Effects of Hydrologic Reg-irne on Nutrient Removal from Wastewate~Using Grass Fi%tration fop Final Treatment, Inst, r Research on band & Water Resources, Unlv, Park, Pa, Research Publ, 88, Penn, State Unlv, Dee" 1934, 65 pp, National Academy of Sciences, AceumuSation sf Nitrate, Wash,, DOC,, 7972,

No1 ley, C, H, and C, h, Rhykerd, 1974, Relationsh?p of Nltrogen Fertlli- zation and Cherna cal Compssl tion of Forage to Anima? Health and Performance. In Forage Fert7%lzats'on, Re W, Howell, ed, The Amer, SOC, of Agronomy, Madison, Wis, pp, 381-382,

Overcash, Ma R, and F, So Humenik, Statehof-the-Art: Swlne Waste Produc- tjon and Pretreatment Processes, EPA, R,S, Kerr Env, Res, Lab,, Ada, Okla, 770 ppo 1976, Overcash, Me R, and F. 9- tlumen~k, Concepts for Pretreatment-band Applica- tks for Small Municipal Systems, In 2nd Nat I Csnf- on Complete Water Use, Water's INtexaface wlth Energy, Air, and Solids. Amer; Inst, of Chem, Engr, , Chacago, Ill, May 4-8, 1975 Overcash, M, R,, A, G. Hashfmoto, D, Lo Redell, and D. Lo Bay, Eualuatlon of Chemical Analyses for Anjmal Wastes, In Standardizfng Properties & Analytical Methods Re1 ated to Anjmal Waste Research, St, Joseph, Mich, Arne~e~So@, Agro Eng, 1975a, pp- 333-355, Overcash, M, R,, D, Covll, G, 1/9, G177lam, Po W, Nesterman, and F, do Humenl k, Ove~land Flow P~et~eatmentof Wastewater, B%0, & Ag , Engineer- trig, Raleigh, Report No, 76-117, Water Resources Resea~chInst- of the Unlversl ty of North Carol-ina, Raleigh, No C, , 1976, Ovescash, M, R, 1975b, North Carol ina State Universi ty. Unpubl lshed data" Overcash, M, R, Imp1 ieat%onsof Overland Flow P~et~eatmentfor Dornest?~ Waste Systems, JWPCF, in preparatj on, 1976a, Palmer, W, C, and A, V, Havens, 1958, A G~aphfcalTechnsque fo~Deter- ma nlng Evapotranspj~ationby the Thornthwa%$eMethod, Monthly Weather Rev4 ew , Apri 1: IZ3-$28,

Phelan, 3, T,, M, F, Bogpep, --e% a%- 1975: Agricultu~alWaste Mana Field Manual, Soi 1 Consewation Service, U, S, Dept, of Wgrieul ture, Pub? lcation Noo 621 -@%/3288, Porter, K, S, , editor, 1975, Nf trogen and Phosphorus Food Production, Waste and the Envi~owment, Ann Arbor Sclence Pub1 ishem, Inc, , po 135-139. F* and C, C, Hortenstine, 9969, Camposted Munf cipal Refuse: Its Effects on Carbon Df oxlde, Nitrate, Fungi, and Sacterla $n Arrendondo Fine Sand, Agronomy Journal , 61 :837-840, Schuman, Go F, and R. E, Burwe7 I, 1974, Precjpi tation Nitrogen Centri bu- "ion Re%atlve to Surface Runoff Di scharges, Journal of Envi ronmental Qua14 ty 3 (4) :366-369, Sievers, Do M, , Go B, Garner and E, E. Plckett, W Lagoon-Grass Terrace System to Treat Swine !dastesa In Proc, of the 3rd In%" Syrnp- on Live- stock Mastes, St. Joseph, Mich, American Soc, Agr, Eng, PROC - 275, April 1975, pp, 541-543, 548,

Stajanovic, B, 9, and M, Alexander, 1958, Effect sf Ino~ganicN% trogen on N%tri f lcat3 on, Soi 1 Sc?ence 86 :208-27 5, Steel, R, Go D, and J, H, Torrie, 1960, Princlp3e.s and Procedures of Statistics, McGraw-Hi 1'1 Book Co, , Mew York, Toronto, London, pp: 67-86, 161-180,

Stevens, To Go and Go Go Dunn. Grass Filtration-Pond Stabilization of Cannfng Waste, a Two-step Processo In 16th Ontarlo Industrial Waste Conference Proc, Toronto, Ontari oo Ontario Water Resources Csmmissf on, June 1969, pp, 161-175,

Thomas, R, E,, KO Jackson and Lo Penrbd, Feasjbility of Overland Flow for Treatment of Raw Domestic Wastewater, R, S, Kerr Envir-. Research Labc Ada, OkTa, EPA-66012-74-087, Environmental Protection Agency, July 4974, 31 pp, Thomas R- E, Overland Flow Treatment sf Raw Domestic Wastewater, R, S, Kerr Envir, Research Lab, €PA, (Presented at Second Nat Y Conf, on Water Reuse, AoI,ChoE0 and €PA, Chicago, May %975), 13 ppo

Thomas, R, E, Spray-Runoff Treatment of Feedl 0% Runoff EPA, Re So Kerr Water Research Center, Ada, Oklahoma, submitted to J, sf Env, Quality, 1972, 11 pp, 45. Trax, J. R. EPA Viewpoint on Land Application of Liquid Effluents, In Proc, of Land Disposal of Municipal Effluents and Sludges. Rutgers Univ. March 1973. pp, 133-142. 46, U, S, Department of Agriculture. Chemical Composition of Forages with Reference to the Needs of the Grazing Animal. July 1969. 47, Walker, R, G. Tertiary Treatment of Effluent from Small Sewage Works Water Pol 1. Contr. : 198-209 , 1972, 48, Wang, J, W. 9976, Chemical Transformations in Soil Cores, Ph.D. Thesis. North Carolina State University, 49, we be^, W. J, , Jr. 1972. Physiochemical Processes for Water Qua1ity Con- trol, Wiley-Interscience, New York, pp. 7-36. 50, Will rich, To Lo and J. 0, Boda, Overland Flow Treatment of Lagoon Efflu- ent. Oregon State University (presented at ASAE meeting December 1976). 51. Witherow, J. L, Small Meat Packers Wastes Treatment Systems. Pacific Northwest Environmental Research Laboratory, EPA (presented at 4th National Symposi um on Food Processing Was ices, Syracuse, March 1973). APPENDIX A fables of Grass Mass Yields, Nitrogen Contents, and Nitrogen Yields TOTAL MASS YIELD OF NITROGEN AND GRASS (Dead Factor included in Calcul atiuns)

Date Terrace 8/7/75 7 .3 254 2 98 3 no measurable growth 4 9 5% 6820 5 71 -6 32% 7-2 - 29 20 193

8/28/75

9/17/75

---.- ---.- Sample grass yield Terrace grass Date Terrace (grams dry wt./wk. ) 1 2 3 4 5 6 7' 8 9 APPENDIX B

Graphical representation of concentration reductions of TKN, O-N,

and NH3-N in OLF effluent during the 171 day experiment wit poul try manure sl wry.

Concentrations of' IbTCtmbacter and IbT~t~osomonusspecies distances along 8bF system, Figure 13.

T2 25-5 rn of flow distance 0 4 8 12 16 20 . 24 TIME, weeks

16 48 m of Slow distance T7 3.8 m of flow distance

g, Nitrosommas

0.01 I f I I I J 0 4 8 12 16 20 24

TIME, weeks

T7 11.4 m of' flow distance 0 Nitrobacter e Nit~osommas T8 25.5 rn of flow distance fl<&~obmte~ T9 40.5 rn of flow distance

APPENDIX C!

Graphical representation of NO3-N concentration in OLF effluent over the period of experimental study.

GLOSSARY

Ag - Arrhenius frequency A9 - alu~inwrn Avy, - average BOD - brochemical oxygen demand BOD5 - five day biszhemical oxygen demand BOT!, - t~ltimatebiological oxygen demand oC - dc(jrees c Cn - calcium CI - chlor~de +-,m - ~entimete~~s CNL - channe7 COD - ilren~lcal sxygerl demand d - dfy D,F, - degrees sf freedom Ea - activation energy Eh - wedox readlnq based on hydrogen electrode E4 - evapotmnspi ra t7 on GLA - gvo~ndlevel application ha -- hectare W, - nu1 1 hypothesis H2S04 - sulfursc acid kg - kilogram 1 - l-itei- ELC - land 1 imiting constituent rn - meters m3 - ewbac meters ml'n, - minute [VIPN - most probable nrlmber per g dry so%l i\i - nitrogen IWa - sodjmm hH3AVG - average value for ammonia nitrogen NH3-N - ammonia nitrogen NHq-N - amanium nitrogen NO3-N - nitrate nitrogen N2 - rnsleeular nitrogen (gas) OGN - organic nitrogen OGNALG - average value for organic nitrogen OLF - overland flow OLFj - overland Plow inflow 0-N - organic nitrogen Org,N - organic nitrogen ppm - parts pep miSI$on R - universal gas constant REG - regular SLC - stream limiting constituent SS - suspended solids Stand, dev, - standard deviation TKN - total Kjeldahl nitrogen TKNAVG - aberage value for total Kjeldahl nitrogen TN - toea1 nitrqen TO@ - total organic catbon IP - total phosphorus 138 t-PQ-P - total phosphd to CIS phos!hnrmr? TS - total solids ISS - total suspended solids YV5 - total volatile solids wt. - weight yr, - year Resultant Publi.catloras

ercash, M.R., Jew. GilPSarn, an F.Jm Brsmenfk, An s~verlanxd flow-lagoon recycle system as a retreatment o poultry waskes. In: Managing Livestock Wastes, Pr c. 3rd Intl. ymp. on Eives~ockr*ialastcs. Umi~r.of %El. her. Sss. Agr. Eng, PROC - 275. p. 618-

Mumenik, F-J., K. E, Snee ercash, J. C, Earker, and G, D, Wetherhfll. tal waste mna rge swine prodtiction faciPity, In :: naging L2ves to 3rd Zntji Smp, ao Livestock Wastes, Uhraiv. of Ill. her. Soe. Agr. Eng. Yroc - 273. -621. 1975.

erlad flow pretreatment of poultry manure. Hurth Carolina State University, M,S. ~hesis' 1976,

Overcash, M.R. Implications of' 14asf;e Systems. --- in preparation,