Section4, 2002-2003

4.0 BOD Concentrations, Loading, and Sources in the
Lower Cape Fear River System

by
Michael A. Mallin
Center for Marine Science
University of North Carolina at Wilmington
Wilmington, NC 28409

An examination of river and stream biochemical oxygen demand (BOD) was conducted over a five-year period in the lower Cape Fear River system, in coastal North Carolina. Median BOD5 was approximately 1.1 mg/L in the Piedmont-derived sixth order Cape Fear River and slightly lower in the two fifth order blackwater tributaries, the Black and Northeast Cape Fear Rivers. BOD in the Cape Fear River was most strongly correlated with chlorophyll a, whereas in the two blackwater tributaries BOD was most strongly correlated with phosphorus concentrations and fecal coliform bacterial counts. This relationship may be a result of nutrient induced increases in heterotrophy, as previous experimental studies have shown that phosphorus additions to blackwater streams lead directly to increased bacterial counts and BOD concentrations. BOD load as lbs BOD/day was correlated much more strongly with river discharge than BOD concentration in all three rivers, with discharge alone able to explain from 40-80% of BOD load variability, depending upon the system. A set of second-to-third order rural streams in the Black River basin was also examined. Median BOD5 concentrations ranged from 0.9-1.2 mg/L in all six tributaries, regardless of land use and watershed size. BOD load varied directly with stream flow. In contrast, BOD5 and BOD20 concentrations in three urban streams in Wilmington, N.C. were approximately double those of the rural streams, with much higher storm event maxima in the urban situations.

The North Carolina Division of Water Quality (NCDWQ 2000) has indicated that the lower Cape Fear River and its estuary is impaired by low dissolved oxygen (DO). Thus, the NCDWQ is requiring a TMDL (total maximum daily load) for biochemical oxygen demand (BOD). Research has confirmed that low DO (between 3 and 5 mg/L) is common in the lower river and estuary during June through September (Mallin et al. 1999; 2002a). Over the past several years the Lower Cape fear River Program has performed a number of BOD related studies to help in understanding the magnitude of this problem and potential sources of BOD.

The Cape Fear River system is a depository for numerous NPDES dischargers, which are point sources of treated effluent into the system (NCDWQ 2000). Point sources are permitted by the NC Division of Water Quality to release a prescribed amount of BOD into the system through their discharges, and are required to report actual amounts discharged. Besides these point sources, BOD may also enter the system through non-point source runoff from agricultural sources such as swine waste lagoon spray field sites, areas where poultry manure is spread, and cattle pastures. Another potential source is natural BOD from organic materials in riparian swamps that flow into the river via tributary streams. Finally, the Cape Fear River receives urban runoff from a number of municipalities and thus non-point source runoff from urban and suburban streams is also a source of BOD to the system.

The Lower Cape Fear River Program (LCFRP) has been collecting BOD data since February 1996. Using these data we describe the seasonal and spatial BOD loads that come into the lower system from the upper and middle Cape Fear watersheds, and the two major blackwater tributaries. The blackwater tributaries drain extensive agricultural areas, and point source discharges are relatively low in volume in these watersheds. Thus, a significant amount of BOD loading to the system is may be derived from non-point sources. However, there is currently no published information available on the variability of BOD loading to the system from non-point sources. Estimating BOD loads requires both assessment of BOD concentrations in the water and computation of stream flow at the time of analysis. During the period May 2000 through June 2003 we collected monthly BOD and streamflow data at six rural streams in the Black River watershed. These collections were made on a pre-set schedule, so they are not storm event samples, but primarily represent base flow conditions. Additionally, the City of Wilmington is funding the Wilmington Watersheds Program, under which the UNC Wilmington Aquatic Ecology Laboratory collects water quality information on urban and suburban watersheds. As a part of this effort we collected BOD data on three urban and suburban streams draining into the Cape fear estuary near the City of Wilmington.

We collected water samples by boat on a monthly basis at six locations in the LCFR system (Fig. 1.1). These sites were the Cape Fear River at Highway NC11 (to measure BOD loads entering the lower CFR mainstem from the Piedmont and upper Coastal Plain); AC (to measure BOD in the mainstem downstream of inputs from a pulp and paper mill on the Cape Fear River and dischargers on Livingston Creek); LVC (to measure BOD in lower Livingston Creek); the Northeast Cape Fear River at Highway 117 (NCF117 - to measure BOD loads from the upper Northeast Cape Fear River basin); the Black river at Highway 210 (B210 - to measure BOD loads from the upper Black River system); and BBT (to measure BOD in the lower Black River that is also influenced by the mainstem CFR via the channel known as Thoroughfare). Samples were collected by hand in acid-cleaned 1L plastic bottles and stored on ice for transport to the laboratory. Data collected during the five-year period from July 1998 through June 2003 are presented within.

Laboratory analyses for BOD followed APHA (1995). In the laboratory, a warm-water bath was used to raise the temperature of the 1L bottles to 20^oC. Samples were then aerated by rapid mixing to ensure adequate initial dissolved oxygen of the sample water. Duplicate 300 mL BOD bottles were filled with sample water, and air bubbles were removed from the shoulder of the bottles by tapping them with an acrylic BOD bottle stopper. Samples were incubated for 20 days at 20.0^o C. Dissolved oxygen was read at the time of setup, day 5, and day 20 using a YSI 57 also recorded at setup, day 5, and day 20. BOD5 and BOD20 measurements (as mg/L BOD) were calculated by subtracting dissolved oxygen on day 5 and 20, respectively, from the initial dissolved oxygen.

Daily river discharge data was obtained from the U.S. Geological Survey for the three main river branches. The flow gauging stations are located at Lock and Dam #1 on the Cape Fear mainstem, near Tomahawk on the Black River, and near Chinquapin on the Northeast Cape Fear River. Average river discharge for each month from July 1998 through June 2003 was converted from CFS to CF/day. BOD (converted from mg/L to lbs/ft³) and flow measurements were then multiplied to obtain average monthly estimates of BOD loading as lbs/day.

BOD and BOD loading data for the three main tributary rivers were entered into a data matrix along with a number of physical, chemical and biological variables collected with the BOD samples, including water temperature, turbidity, total nitrogen (TN), nitrate-N, ammonium, total phosphorus (TP), orthophosphate-P, chlorophyll a and fecal coliform bacteria counts. River discharge data were included in the matrix, both as flow on the day of collection and as average flow for the seven-day period preceding sampling. Correlation and regression analyses were performed using SAS for each of the three main tributaries to assess major factors influencing BOD and BOD load over the five-year period July 1998 through June 2003.

During the period May 2000 - June 2003, samples were collected monthly from the following second and third order streams: Colly Creek (COL), Great Coharie Creek (GCO), Little Coharie Creek (LCO), Hammond Creek (HAM), Browns Creek (BRN), and Six Runs Creek (6RC). COL, GCO, LCO and 6RC are located in the Black River Basin and HAM and BRN empty into the mainstem of the Cape Fear River (Fig. 1.1). A bucket and rope were used to collect water mid-stream from a bridge. Acid-cleaned 1L plastic bottles were filled from the bucket and stored on ice for transport to the laboratory.

For the stream stations flow was measured mid-stream from a bridge using a Marsh-McBirney Flo-Mate Model 2000. A lead weight and fin apparatus were used to keep the flow sensor motionless in the water column and pointed into the current. Flow data were obtained as m/s. A lead line with 0.5 m gradations was used to measure depth at 3 m intervals across the stream. From these measurements average depth was computed. Average depth was multiplied by stream width to obtain the cross-sectional area of the creek in m². Volume of flow was calculated by multiplying flow by cross-section area of the stream to obtain m³/s, subsequently converted to m³/day. BOD5 and BOD20 were converted to lbs BOD/m³, and multiplied by daily flow. BOD loading was computed as lbs BOD/day.

Additional BOD data were collected from three urban and suburban streams, as a part of the Wilmington Watersheds Program (Mallin et al. 2003). Smith Creek drains into the Northeast Cape Fear River just upstream of the City of Wilmington, and Barnards and Motts Creeks drain into the Cape Fear Estuary downstream of the Wilmington port area. Smith Creek was sampled from the Castle Hayne Road bridge, and Barnards and Motts Creeks were sampled from bridges on River Road, using the bucket technique as described above. Data presented here are from February 2001 through April 2003. Flow data from these three stations are not available.

During the five-year period from July 1998 through June 2003, BOD among the major tributaries of the lower Cape Fear River system showed little variability (Table 4.1). Median BOD5 of the water entering the lower system at Station NC11 was 1.1 mg/L, slightly higher than that of the two blackwater tributaries, the Black and Northeast Cape Fear Rivers (Table 4.1). Between NC11 and AC, located about two miles downstream of International Paper (IP), BOD5 and BOD20 concentrations increased of about 27% and 31%, respectively. This increase was either due to inputs from IP, Livingston Creek, or some combination of the two sources. BOD5 and BOD20 in Livingston Creek are both 30-34% higher than water from NC11. However, Livingston Creek has been sampled only about 50 m up from the mouth; thus, at times this station receives significant inputs of water from the river channel. Median ratios of BOD20 to BOD5 varied from a low of 2.6 at NC11 to a high of 3.1 at LVC.

Peak BOD concentrations were generally found during or following rain events and subsequent runoff episodes. In the main Cape Fear River channel the BOD5 maximum of 2.4 mg/L occurred in February 2001, under moderate flow conditions (Fig. 4.1). The BOD20 maximum of 8.6 mg/L occurred in December 2000, under conditions of relatively low flow (Fig. 4.1). However, peak BOD5 and BOD20 concentrations at AC, BBT, B210 and NCF117 all occurred in September 1998, following Hurricane Bonnie. This hurricane impacted the Northeast Cape Fear and Black River watersheds in particular, with little effect in the Piedmont (Mallin et al. 2002a).

Area of origination did not have a major influence on long-term BOD (BOD20) compared with BOD5. The ratio of BOD20 to BOD5 in the Black and Northeast Cape Fear Rivers was 2.9 in both cases; at BBT it was 2.8 and at Livingston Creek (blackwater stream) it was 3.1. At NC11 it was 2.6 and at AC it was 2.7, indicating that the blackwater influence provided somewhat more recalcitrant material to the load, whereas the inputs from the upper and middle Cape Fear basins provided somewhat more labile BOD.

BOD concentrations among the six stream stations showed little variability, despite differences in discharge, watershed size, and land use. Median BOD5 among the streams ranged from 0.9 - 1.2 mg/L, and median BOD20 ranged from 2.5 - 3.6 mg/L. Mean values of both parameters were likewise in those ranges (Table 4.2). Median ratios of BOD20 to BOD5 varied from a low of 2.5 at Browns Creek (BRN) to a high of 3.1 in Little Coharie Creek (LCO).

In contrast to the main river channels and the rural streams, the urban and suburban streams yielded notably higher BOD concentrations (Table 4.3). Both BOD5 and BOD20 yielded median and mean concentrations approximately twice those of the rural stream sites. The maximum BOD5 values found in the urban streams were also twice as high as the maximum values in the rural streams, whereas maximum BOD20 values at the urban sites were 2-3 times as high as in the rural streams (Table 4.3). Median BOD20 to BOD5 ratios varied from a low of 2.8 at Motts Creek to a high of 3.8 at Barnards Creek.

BOD Loading to the Lower System

The mainstem of the Cape Fear River provided by far the largest BOD load to the lower system, approximately 77% of the total (Fig. 4.2a). This load was considerably increased by inputs from International Paper and Livingston Creek according to data accumulated from Station AC (Fig. 4.2b). Median load increased by 37% at AC relative to the upstream station NC11.

BOD loads in the Black and Northeast Cape Fear Rivers contributed relatively minor (10% and 11%, respectively) amounts of total system BOD load compared with the mainstem (Table 4.1). We were unable to compute a daily load at BBT due to lack of accurate nearby river discharge data, but average BOD5 and BOD20 values at that station fell between those at NC11 and AC (Table 4.1). BBT is in an area strongly affected by tides, and also receives mainstem CFR BOD inputs via the channel known as Thoroughfare.

There is a pronounced seasonal signal in BOD loading to the lower system (Fig. 4.2). The data exhibit an annual winter-spring loading increase in all three main tributaries, but especially so in the mainstem. This is likely due to a combination of factors. During this period river flow is normally high due to the cooler weather and reduced evapotranspiration. Increased river flow should bring about increased non-point source runoff from agriculture and urban sources, as well as loading of decaying detrital matter from riparian swamp forests. Also, there are occasional spring algal blooms in the mainstem that die and subsequently contribute to the BOD load. Finally, because cooler water holds more dissolved oxygen, many dischargers are permitted to increase their BOD loads to the rivers in winter.

Peak loading rates occurred in different months than peak concentrations. At NC11 peak loadings of BOD5 and BOD20 were 150,921 and 409,643 lbs/day, respectively, in April 2003, a month of very high river flow (Fig. 4.1). During that same month peak loadings at AC of BOD5 and BOD20 were 237,162 and 625,244, respectively. In the two major blackwater tributaries peak loadings were reached in September 1999, following Hurricane Floyd. Maximum BOD5 and BOD20 loadings at B210 were 31,302 and 97,036 lbs/day, respectively, and maximum at NCF117 were 47,366 and 102,627 lbs/day, respectively. In addition, elevated BOD loading occurred following Hurricane Bonnie in September 1998, especially in the blackwater tributaries. Thus, stream discharge determined BOD loading more than BOD concentrations, at least at the concentrations found in this study.

Probably the most realistic measure of the load is obtained by using the median. This reduces the effect of data outliers (such as generated during hurricanes and droughts). Between NC11 and AC the median increase is thus 9,060 lbs/day of BOD5. Discharger self-reported data from International Paper shows that median rate of 4,169 lbs/day of BOD5 originated from this industry from 1998-2003, or 46% of the BOD5 increase between the two stations. Based on these figures, the other 54% of the BOD5 originated either from point sources in Livingston Creek and/or non-point sources in Livingston Creek or the Cape Fear River.

BOD loading from the rural streams to the main river channels differed considerably, ranging from a low of 33 lbs/day at Hammonds Creek to a high of 978 lbs/day at Six Runs Creek (Table 4.2). This wide range was due to the broadly differing streamflow regimes among these streams. In other words, the largest creeks such as 6RC, GCO, LCO and COL had much greater BOD loading to the system than the small creeks such as HAM and BRN.

Correlation analyses indicated that BOD5 and BOD20 were positively correlated with several factors (Table 4.4). At NC11 BOD5 was positively correlated with turbidity, fecal coliform counts, and especially chlorophyll a, and BOD20 was positively correlated with chlorophyll a only. The positive correlation between BOD5 and fecal coliform bacteria may indicate that a portion of the BOD-producing materials are likely derived from the same sources as fecal coliform bacteria, possibly livestock grazing areas, swine lagoon spray fields, and/or human sewage effluents. Also, bacteria in general are heterotrophs, using up dissolved oxygen during respiration, and fecal coliforms may contribute to BOD in this manner (Mallin et al. 2002b). Turbidity was also strongly correlated with fecal coliforms, indicating that non-point source runoff of wastes is an important issue. Turbidity was also strongly correlated with river flow, indicating upstream sedimentation problems and long-distance transport of turbidity. Dr. Lynn Leonard of UNCW has analyzed turbidity particles from NC11 and indicated that these particles are characteristic of the Piedmont and upper Coastal Plain. BOD5 and BOD20 loads were positively correlated with turbidity and fecal coliforms at NC11, as well as with river flow on the day of sample collection and average river flow for the seven days preceding sample collection at all three stations (Table 4.4). Water temperature was inversely related to BOD load; this was likely a result of higher river discharge during the cooler months. At NC11 BOD5 concentrations were weakly correlated with BOD5 loads (r = 0.30, p = 0.02). The correlation between BOD load and river discharge was much stronger, evidence that the rather low variability and ranges of BOD at this station do not strongly affect BOD load, whereas river discharge does (Fig. 4.1).

The relatively strong correlation with chlorophyll a in the Cape Fear River at NC11 is likely a result of algal biomass senescing in the BOD samples during incubation. Nutrient addition bioassay experiments have demonstrated that nutrient inputs lead directly to chlorophyll a increases in experimental chambers, and have the secondary effect of causing significant BOD increases (Mallin et al. 2002b; Mallin et al. in press). Strong positive correlations between phytoplankton biomass and BOD have also been reported from Minnesota rivers (Heiskary and Markus 2001) as well as tidal creeks in coastal North Carolina (MacPherson 2003). Median BOD5 in the Cape Fear River was in the low range of the Minnesota rivers investigated by Heiskary and Markus (2001), and the mean 2002-2003 chlorophyll a concentration in the Cape Fear River (4.3 mg/L) was comparable to the chlorophyll a values in the Minnesota Rivers expressing BOD5 in the 1.0-1.2 mg/L range.

In the Black River, BOD5 showed a positive correlation with fecal coliforms, and a positive correlation with orthophosphate as well. In Minnesota rivers, positive correlations between BOD and phosphorus were reported from a number of systems (Heiskary and Markus 2001). BOD20 was positively correlated with water temperature, fecal coliform counts, orthophosphate, TP, and flow (Table 4.4). BOD5 and BOD20 loads were strongly correlated with river flow, but were not correlated with BOD concentrations. In the Northeast Cape Fear River, both BOD5 and BOD20 were significantly correlated with turbidity, fecal coliforms, orthophosphate, TP, and flow. In this river, turbidity was also correlated with fecal coliform counts. BOD5 and BOD20 loads were strongly correlated with river flow, and also correlated with fecal coliforms, orthophosphate, and TP (Table 4.4). In this river BOD concentrations were highly significantly correlated with BOD loads (p < 0.001).

The lack of correlation between BOD concentration and chlorophyll a in the two blackwater rivers is a result of the low phytoplankton biomass. The deep, well-mixed, humic-stained waters retard phytoplankton growth (Mallin et al. 2001; Mallin et al. in press). However, the positive correlations between phosphorus and BOD in these blackwater streams are not surprising. Nutrient addition bioassay experiments have demonstrated that additions of phosphorus, especially organic phosphorus, lead directly to significant increases in BOD, ATP biomass, and bacterial abundance (Mallin et al. 2001; Mallin et al. 2002b; Mallin et al. in press). Phosphorus-induced increases in bacterial abundance have been reported from salt marsh environments as well (Sundareshwar et al. 2003).

Linear regression analyses were used to derive predictive equations for BOD5 and BOD20 concentrations in the three main tributaries of the Cape Fear system (Table 4.5). For the Cape Fear River mainstem, models involving chlorophyll a along with either turbidity or total phosphorus were the best predictors of BOD5, although neither was able to account for more than 39% of the variability. The best predictors of BOD20 were models using these same two variables, although both accounted for only 19% of the variability in BOD20 concentration (Table 4.5). The best predictive model for BOD5 in the Black River combined fecal coliform counts with TP, accounting for only 18% of the variability. BOD20 in the Black River was best predicted by a model utilizing river discharge on the sampling day along with TP, accounting for 25% of the variability in BOD20 concentration (Table 4.5). In the Northeast Cape Fear River two models using fecal coliform counts and either river discharge or TP both accounted for 67% of the variability in BOD5. These same two variables best predicted BOD20 concentration, with the discharge plus fecal coliform count model accounting for 66% of BOD20 variability and TP plus fecal coliform count model 61% of the variability (Table 4.5).

Prediction of BOD Load

The two components of BOD load are BOD concentration and stream discharge. River discharge was strongly correlated to BOD in all three rivers, much more strongly than BOD concentrations (Table 4.4; Fig. 4.1). We wanted to determine the extent that river flow (a parameter that is measured continuously by USGS using instrumentation) could be used, either alone or with other parameters, to predict BOD loading to the lower Cape Fear Basin. We used linear regression analysis to evaluate such predictive equations.

Regression modeling indicated that the best single-variable model for predicting BOD5 load arriving at NC11 involved river flow on the day of sample collection, accounting for 69% of the variability in BOD5 load. Adding variables to the model provided little more predictive power; addition of turbidity increased the r² to 71% (Table 4.6). River discharge alone accounted for 79% of the variability in BOD20 load, with addition of other variables providing negligible improvement to the model (Table 4.6). Models using river discharge alone accounted for only 40% of the variability in both BOD5 and BOD20 load in the Black River, with no improvement from addition of other variables (Table 4.6). For the Northeast Cape Fear River, discharge alone accounted for 60% of the BOD5 load variability with no further improvement from other variables. Discharge alone accounted for 68% of the variability in BOD20 load, with addition of fecal coliform counts marginally improving that to 71% (Table 4.6).

To summarize, river flow alone can be used to predict a substantial amount of the variability in BOD load from the mainstem CFR and the Northeast Cape Fear River. However flow alone or in combination with the other factors tested did not predict much of the BOD load from the upper Black River. As noted, higher flow occurs in winter, when larger amounts of BOD are permitted to be released by point source dischargers. Also, greater river flow leads to greater non-point source inputs of BOD. The statistical relationship between turbidity (an indicator of non-point source runoff) and fecal coliform counts, and the correlation between BOD and fecal coliform counts both indicate a strong non-point source BOD source in the Cape Fear River system.

Acknowledgments

For funding we thank the Lower Cape Fear River Program and the Water Resources Research Institute of the University of North Carolina. Field and laboratory help was provided by Scott Ensign, Virginia Johnson, Tara MacPherson, Matthew McIver, Doug Parsons and Heather Wells. River flow data were provided by the U.S. Geological Survey, Raleigh, N.C., and rainfall data were provide by the State Climate Office, North Carolina State University, Raleigh. Robert Farmer of the North Carolina Division of Water Quality provided us with NPDES discharger BOD data.

APHA. 1995. Standard Methods for the Examination of Water and Wastewater, 19th ed. American
Public Health Association, Washington, D.C.

Heiskary, S. and H. Markus. 2001. Establishing relationships among nutrient concentrations, phytoplankton
abundance, and biochemical oxygen demand in Minnesota, USA, rivers. Journal of Lake and
Reservoir Management 17:251-267.

MacPherson, T.A. 2003. Sediment oxygen demand and biochemical oxygen demand: patterns of oxygen
depletion in tidal creek study sites. M.S. Thesis, the University of North Carolina at Wilmington,
Wilmington, NC. 55 pp.

Mallin, M.A., M.R. McIver, S.H. Ensign and L.B. Cahoon. Photosynthetic and heterotrophic impacts of
nutrient loading to blackwater streams. Ecological Applications (In press).

Mallin, M.A., L.B. Cahoon, M.R. McIver, D.C. Parsons and G.C. Shank. 1999. Alternation of factors
limiting phytoplankton production in the Cape Fear Estuary. Estuaries 22:985-996.

Mallin, M.A., L.B. Cahoon, D.C. Parsons and S.H. Ensign. 2001. Effect of nitrogen and phosphorus 1
loading on plankton in Coastal Plain blackwater streams. Journal of Freshwater Ecology 16:455-466.

Mallin, M.A., M.H. Posey, M.R. McIver, D.C. Parsons, S.H. Ensign and T.D. Alphin. 2002a. Impacts and
recovery from multiple hurricanes in a Piedmont-Coastal Plain river system. BioScience 52:999-1010.

Mallin, M.A., L.B. Cahoon, M.R. McIver and S.H. Ensign. 2002b. Seeking science-based nutrient standards
for coastal blackwater stream systems. Report No. 341. Water Resources Research Institute of the
University of North Carolina, Raleigh, N.C.

Mallin, M.A., L.B. Cahoon, M.H. Posey, D.C. Parsons, V.L. Johnson, T.D. Alphin and J.F. Merritt. 2003.
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and Natural Resources, Division of Water Quality, Water Quality Section, Raleigh, NC, 27699-1617.

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ecosystem processes. Science 299:563-565.

Table 4.1. Descriptive statistics of biochemical oxygen demand (BOD) collected at six LCFRP river
stations, July 1998 – June 2003.
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Creek NC11 AC LVC BBT B210 NCF117
______________________________________________________________________

Mean (mg/L) 1.2 1.6 1.4 1.2 0.9 1.0

Median
Load (lbs/d) 15,748 24,808 2,300 2,477 ______________________________________________________________________

Median
Load (lbs/d) 50,994 66,212 6,544 7,096
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Table 4.2. Descriptive statistics of biochemical oxygen demand (BOD) collected at six
Black River basin stream stations, May 2000 – June 2003.
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Median
Load (lbs/d) 978 827 923 35 33 687 _____________________________________________________________________

Median
Load (lbs/d) 2,410 2,480 3,003 86 79 1,844
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Table 4.3. Descriptive statistics of biochemical oxygen demand (BOD) collected at three
urban stream stations in the Cape Fear Estuary, February 2001 – April 2003.

Median 1.8 1.6 2.2
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Median 5.8 6.0 6.1
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Table 4.4. Correlation analyses between BOD and various physical and biological parameters for the mainstem Cape Fear (NC11), Black (B210), and Northeast Cape Fear (NCF117) Rivers, July 1998 - June 2003.

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NCF117