Hydrologic Year 2015 Turbidity Data Submittal Report

Transcription

1 P.O. Box 712 Scotia, CA Phone (707) Fax (707) Hydrologic Year 2015 Turbidity Data Submittal Report Elk River Freshwater Creek Bear Creek February, P age

2 Table of Contents 2015 TURBIDITY TREND DATA SUBMITTAL TABLE OF CONTENTS... 2 LIST OF TABLES... 2 LIST OF FIGURES... 2 INTRODUCTION... 4 MONITORING SITE LOCATIONS... 5 METHODS AND SITE OPERATIONS... 8 HYDROLOGIC MONITORING SITE OPERATIONS... 9 DATA PROCESSING METHODS... 9 HY2015 DATA SUMMARY Data Quality REFERENCES APPENDICES APPENDIX A. DATA VALIDATION CODES List of Tables TABLE 1. HYDROLOGIC STATIONS ELK RIVER... 5 TABLE 2. HYDROLOGIC STATIONS FRESHWATER CREEK... 6 TABLE 3. HYDROLOGIC STATIONS LOWER EEL... 6 TABLE 4. WATERSHED OPERATING PROTOCOLS DESCRIBING FIELD AND LABORATORY METHODS USED IN HYDROLOGY STATION MONITORING TABLE 5. EQUIPMENT USED IN THE FIELD AND LABORATORY FOR HYDROLOGIC MONITORING AND INSPECTION SCHEDULE TABLE 6. INSTRUMENT DEPLOYMENT AT TURBIDITY TREND HRC HYDROLOGY SITES TABLE 7. ANNUAL DATA OBJECTIVES FOR HYDROLOGIC MONITORING SITES TABLE 8. SUMMARY DISCHARGE AND ANNUAL SEDIMENT LOAD List of Figures FIGURE 1. LOCATION MAP OF HRC HYDROLOGIC MONITORING SITES IN THE ELK RIVER WATERSHED FIGURE 2. LOCATION MAP OF LOWER EEL HYDROLOGY SITES... 9 FIGURE 3. TURBIDITY AND STREAM DISCHARGE MEASUREMENT AT HRC MONITORING STATIONS FIGURE 4. EXAMPLE RELATIONSHIP BETWEEN STAFF PLATE AND PRESSURE TRANSDUCER FIGURE 5. EXAMPLE RELATIONSHIP BETWEEN STAGE AND DISCHARGE FIGURE 6. EXAMPLE RELATIONSHIP BETWEEN FIELD AND LABORATORY TURBIDIMETERS FIGURE 7. EXAMPLE RELATIONSHIPS BETWEEN TURBIDITY AND SSC AT STATION FIGURE 9. EXAMPLE CORRECTED DATA P age

3 PROJECT TITLE: 2015 TURBIDITY TREND DATA SUBMITTAL ELK RIVER WATERSHED WASTE DISCHARGE PERMIT R FRESHWATER CREEK WATERSHED WASTE DISCHARGE PERMIT R HY ANNUAL TURBIDITY TREND STATION DATA SUBMITTAL AND SUMMARY REPORT ORGANIZATION IMPLEMENTING THE PROJECT: Humboldt Redwood Company PO Box Main St. Scotia, CA I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system, or those directly responsible for gathering the information, the information submitted, is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. HYDROLOGY TEAM LEADER FOR THIS PROJECT Nicolas Harrison Date HUMBOLDT REDWOOD COMPANY FOREST SCIENCES DIRECTOR Mike Miles Date 3 P age

4 Introduction 2015 TURBIDITY TREND DATA SUBMITTAL Suspended sediment and streamflow are measured at ten (10) hydrologic monitoring stations in the Elk River watershed, nine (9) locations in the Freshwater Creek watershed, and one (1) location in the lower Eel River watershed (Tables 1-3, Figures 1-2). The objective of these stations is to monitor sediment conditions within the watersheds Measurements at each station include: Continuous electronic recording of turbidity. Continuous electronic recording of water depth. Manual collection of water samples with ISCO automated pumping samplers for analysis of total suspended sediment concentration and turbidity. Manual collection of water samples using depth-integrating techniques for analysis of suspended sediment concentration and turbidity. Manual collection of streamflow area and velocity using wading and non-wading techniques for calculation of streamflow volume. A more detailed project objective is to measure a complete record of streamflow and its relationship to stage, and sediment and turbidity samples collected over a range of flows. The data objectives are to ensure a data record that is sufficiently complete that the following analyses can be accomplished: Computation of annual suspended sediment load. Assess differences in suspended sediment (SSC) and turbidity with management and natural disturbances on and annual and stormflow basis. Assess trends in SSC and turbidity with implementation of the management practices applied in the watershed through the NCRWQCB permits and Humboldt Redwood Company s (HRC) Habitat Conservation Plan and Company policies. Each year, raw and processed data are submitted to the North Coast Regional Water Quality Control Board per requirements of the Watershed Waste Discharge Permit for Elk River (R ) and Freshwater Creek (R ). This report supports the data submission for hydrologic year 2015 reporting data collected from October 15, 2014 to May 15, P age

5 Monitoring Site Locations Table 1. HRC hydrologic monitoring stations in the Elk River watershed for the 2015 hydrologic year. HRC Station Number Station Description Basin Area (km 2 ) 188 South Fork Elk River Mainstem Elk River South Fork Elk River North Fork Elk River Bridge Creek North Fork Elk River at HRC Road #16 bridge Tom s Gulch Little South Fork Elk River in BLM Headwaters Reserve West Branch Railroad Gulch East Branch Railroad Gulch P age

6 Table 2. HRC hydrologic monitoring stations in the Freshwater watershed for the 2015 hydrologic year. HRC Station Number Station Description Basin Area (km 2 ) 523 Mainstem Freshwater Creek at confluence with South Fork Freshwater Creek Mainstem Freshwater Creek near Incline Upper mainstem Freshwater Creek above HRC Road # McCready Gulch Cloney Gulch Graham Gulch South Fork Freshwater Creek Little Freshwater Creek Unnamed tributary to Freshwater Creek, referred to as "Beck's Tributary" 2.17 Table 3. HRC hydrologic monitoring stations in the Lower Eel watershed for the 2015 hydrologic year. HRC Station Number Station Description Basin Area (km 2 ) 533 Bear Creek P age

7 Figure 1. Map of HRC hydrologic monitoring stations in the Elk River and Freshwater watersheds for the 2015 hydrologic year. 7 P age

8 Figure 2. Map of HRC hydrologic monitoring stations in the Lower Eel River watershed for the 2015 hydrologic year. Methods and Site Operations ISCO portable samplers (Teledyne ISCO Technologies, Inc.) are triggered to collect in-stream samples based on a rise in water level, or stage (Figure 3). A program is loaded into the data logger (WaterLOG by YSI, Inc.) that triggers the ISCO sampler to begin sampling based on a user-specified rise in stage within a 15-minute interval. The program runs in 2 segments (an A program and B program segment) that specifies how many bottles to fill during each program segment. The objective is for samplers to pump on the rising (A program) and falling stage limb of the storm hydrograph (B program). Sampling intervals may be varied through the season based on completion of various project objectives. Stream samples in the ISCO samplers are collected within 1 week following sampling and submitted to the HRC laboratory for analysis of suspended sediment concentration. Turbidity is recorded at 15-minute intervals using a DTS-12 turbidimeter (Forest Technology Systems). Water level is recorded at 15-minute intervals with independent pressure transducers 8 P age

9 (Druck by General Electric Measurement and Control) that either mounted to the streambed or affixed to a gas bubbler system. Stream flow data are generated using water level measurements from the recording devices calibrated to a staff plate that is read by the field crew during each station visit. See Table 4 for complete details regarding the specifications of monitoring site infrastructure. Stage is converted to stream flow by a stage-discharge rating curve that is developed for each site using stream discharge measurement s taken over a wide range of flows (Figure 3). The data used to develop the stage-discharge rating currently in use is considered valid until a channel change (as indicated by channel cross-section measurements) is sufficient enough to require a new stagedischarge rating to be developed. Thus, data from several years may be included in each stagedischarge rating curve. Depth-integrated point samples are collected across the range of flows and submitted for lab analyses of turbidity and suspended sediment concentration. These samples are used to validate ISCO samples that are collected at one point in the water column. Grab samples are also collected and submitted for lab analysis of turbidity only. Grab samples are used to compare with the turbidimeter data for calibration of the field and lab turbidity instruments. HRC s methods for site installation, equipment, field measurements of sediment and streamflow, and sediment laboratory processing are provided as Standard Watershed Operating Protocols (SWOP s) listed in Table 4. HRC operates a laboratory accredited under the California Environmental Laboratory Accredidation Program (#2952) that processes all water quality samples. Laboratory methods are described in PALCO SWOP-05 and the laboratory quality assurance and control program is described in the laboratory QAPP documentation. Hydrologic Monitoring Site Operations Streams are equipped with continuous measuring turbidimeters and depth recorders. Electronically measured turbidity is measured every 15 minutes and calibrated with water samples collected or pumped from the streams and processed in the laboratory. Water samples are pumped from the stream triggered by changes in water depth. Depth recordings are calibrated with observations of staff plate depth. Stage/discharge relationships are developed at each site. See HRC Standard Watershed Operating Protocols (1-4 and 57) which describe streamflow and sediment sampling procedures, instrumentation, and laboratory methods. This combination of measures allows the continuously recorded turbidity and depth to be translated to streamflow (m 3 /s) and sediment load (metric tons). These are summed to produce annual sediment load, expressed in metric tons, or sediment yield per unit watershed area, expressed in mtons/km 2. A variety of turbidity instruments are used (Tables 5, 6). Therefore, reported turbidity from the field 9 Page

10 is calibrated to the laboratory HACH 2100N instrument by building relationships between field and laboratory turbidimeters with physically collected samples. Table 4. Standard Watershed Operating Protocols describing field and laboratory methods used in hydrology station monitoring. Number Title Current Version Description SWOP-01 Hydrologic Site Selection, Monumenting and Documentation 2.3 Establishing and documenting a permanent monitoring station. SWOP-02 Gaging Streams for Estimating Discharge 3 Installing a staff plate, measuring streamflow, constructing a stage-discharge rating curve. SWOP-03 Instrumentation Methodology 1.2 Turbidimeters, water samplers, pressure transducers, and rain gauge manuals SWOP-04 Water Quality Grab Sampling and Field Turbidity Measurement 2.1 Depth-integratred sampling methods and portable turbidimeter manual SWOP-57 Laboratory analysis of suspended sediment using electronic data collection methods 4.3 Turbidity and sediment concentration laboratory measurement. SWOP-19 Establishing and maintaining the physical infrastructure of a hydrologic monitoring station 1.1 Hydrologic monitoring station set-up. Figure 3. Turbidity sampling (left) and stream discharge measurement (right) at HRC hydrologic monitoring stations. 10 P age

11 Table 5. Equipment used in the field and laboratory for hydrologic monitoring and inspection schedule. Equipment/Model No. Instrument Accuracy Inspection Frequency Type of Inspection Inspector Water Logger Data Logger (by Design Analysis) Marsh-McBirney Flo- mate 2000 NA Weekly Check data download Range: m/s Zero Stability: ± 0.15 m/s Accuracy: ± 2% reading + zero stability Field crew Each use Proper operation Field crew ISCO Automated Pump Sampler, Model 6100 or 6712 DTS-12 turbidimeter NA Range: NTU Zero offset: ± 0.2 NTU Accuracy: ± 2% 0 to 500, ±4% Weekly, or within 48 hours after significant storm event Proper operation Field crew Weekly Proper operation Field crew Temp: ±0.20 o C Druck Pressure Transducer Model HACH 2100N Lab Turbidimeter Range 75 mbar to 60 bar Accuracy: ± 0.1% Range: NTU Accuracy: <100 NTU ± 2% ± 5% Weekly Check data logger and check with staff plate Daily, when used Calibration Proper operation Field crew Lab leader Denver Instruments APX-100 Analytical Balance Range: to g Accuracy: ± g Daily, when used Weigh check weights Lab leader XP-3000 Top-loading Balance Range: 0.1 to grams Accuracy: ±0.1 g Daily, when used Weigh check weights Lab Leader Lab Oven Accuracy: 1 o C Each use Proper operation Lab leader Vacuum Apparatus NA Each use Proper operation Lab leader 11 P age

12 Table 6. Instrument deployment at HRC hydrologic monitoring stations during the 2015 hydrologic year. Station Stream Name Turbidimeter Water Level Data Recorder ISCO Serial # High Q Sampling 509 Mainstem Elk River DTS-12 Gas Bubbler Water Logger 6712 Bridge 510 South Fork Elk River DTS-12 Druck Water Logger 6712 Cable system 511 North Fork Elk River DTS-12 Druck Water Logger 6712 Cable system 532 North Fork Elk River DTS-12 Druck Water Logger 6712 Bridge 517 Bridge Creek DTS-12 Druck Water Logger 6712 Platform 533 Tom s Gulch DTS-12 Druck Water Logger 6712 Platform 683 Railroad Gulch West Branch DTS-12 Druck Water Logger 6712 Platform 684 Railroad Gulch East Branch DTS-12 Druck Water Logger 6712 Platform 188 South Fork Elk River DTS-12 Druck Water Logger 6712 Bridge 534 Little South Fork Elk River DTS-12 Druck Water Logger 6712 Temporary platform 523 Freshwater Creek DTS-12 Druck Water Logger 6712 Cable system 502 Freshwater Creek at Incline DTS-12 Druck Water Logger 6712 None 526 Upper Freshwater Creek DTS-12 Druck Water Logger 6712 Temporary platform 527 McCready Gulch DTS-12 Druck Water Logger 6712 Temporary platform 504 Cloney Gulch DTS-12 Druck Water Logger 6712 Cable system 505 Graham Gulch DTS-12 Druck Water Logger 6712 None 506 South Fork Freshwater Creek DTS-12 Druck Water Logger 6712 Temporary platform 528 Little Freshwater Creek DTS-12 Druck Water Logger 6712 Cable system 500 Beck s Tributary DTS-12 Druck Water Logger 6712 Temporary platform 530 Bear Creek DTS-12 Druck Water Logger 6712 Bridge 12 P age

13 Data Processing Methods Data goals for each monitoring station as stated in the Quality Assurance Program Plans Are that the data record will be sufficiently complete so that the following analyses can be accomplished: Determine flood frequency and return intervals. Calculate annual suspended sediment loads. Assess differences in SSC and turbidity with management and natural disturbances on and annual and stormflow basis. Assess trends in SSC and turbidity with implementation of sediment reduction measures in the context of climate specified in the HCP and by NCRWQCB. Table 7. Annual data objectives for hydrologic monitoring sites. Data Objective Measurement Objective Achieve a complete record of flow Maintain a complete discharge record: water level record >95% complete Complete discharge measurements over a range of flow from low flow to bankfull 15+ viable measurements well distributed over the range of observed flows. Achieve a reasonably complete record of sediment discharge Maintain a complete turbidimeters record: >95% operative through season Achieve a reasonably accurate estimate of the annual load of suspended sediment Complete sufficient manual SSC samples well distributed over the range of observed flows and throughout the winter season to determine sediment rating curve: 150+ Complete sample of storm events Continuous samplers operative for largest 90% of storms Relationships between Water Depth, Staff Plates and Discharge: The water level recorded by the pressure transducer is translated to the staff plates at each station by correlating observed stage with the electronic readings at the time of the observation (Figure 4). This relationship is developed each year for each of the sites based on the field visit observations. HRC has devised an apparatus installed at each site that firmly holds the stream depth measurement 14 P age

14 device in place and allows the operator to return the device to the same position after servicing. This has virtually eliminated the need for depth adjustments to the continuous records during the season that may be necessary to match the records when the instrument position is moved. Figure 4. Example relationship between the pressure transducer (x-axis, e-stage) and the staff plate (y-axis, observed stage) at Lower South Fork Elk River (Station 530). Blue diamonds indicate observed stage measurements vs. pressure transducer readings (e-stage). Red squares indicate potential outliers which are likely a result of staff misreading the staff plate. A stage vs. discharge rating curve is developed at each site based on stream discharge (Q) measurements taken across a range of observed stream depths (stage). High flow discharges that exceed bankfull are less common and are generally under-represented in the measured data at nearly all the sampling sites. To estimate the flow above measured depths, we project the rating curve beyond measured values. Continuous discharge estimate beyond the range of empirical data should be viewed as highly preliminary and somewhat subjective. Each site currently has a verified rating curve. Some discharge measurements are made each year to check whether contemporary rating data continues to trend with past measurements. A change in channel configuration, such as aggradation, scour or bank erosion may sufficiently change the stage vs. discharge relationship to warrant the construction of a new rating curve. New measurements 15 P age

15 exhibit a poor relationship on existing rating curves usually indicate changing channel conditions. This situation is verified by annual cross-section measurements completed at the end of each hydrologic season. An example of a verified stage vs. discharge rating curve is shown in Figure 5. It is common for some scour or aggradation to occur within the discharge cross-section at most sites since they are run of the river and are not controlled by a weir or flume. Stations were originally selected to minimize change in the local reach. Most are sufficiently stable to allow the use of the same rating curve for many years. A few stations have been very unstable requiring considerable measurement each year, most notably Tom s Gulch (Station 533), and Bear Creek (Station 530). Figure 5. Example of a stage vs. discharge rating curve from the Upper North Fork Elk River (Station 532). Yellow dots represent low-flow data and green dots represent high-flow data. A segment break was identified at 0.65m. Relationships between Turbidity and Suspended Sediment Concentration: We construct relationships between the field turbidimeter (DTS-12), the laboratory turbidimeter (HACH 2100N) and suspended sediment concentration (Figure 6). There is no standard for turbidity measurement common to all of the measurement devices, including the instream turbidimeters we deploy and the laboratory turbidimeter used to process all of the physical samples. We have also observed that individual turbidimeters of the same brand do not read identically. Each instrument requires individual calibration on some schedule. We build a relationship between field instrument turbidity and the laboratory turbidity of the physical samples collected at each site each year. This relationship is used at various next steps in the process. 16 P age

16 Figure 6. Example relationship between field (DTS-12) and laboratory (HACH 2100N) turbidimeters at South Fork Elk River (Station 510). Blue dots indicate field vs. lab turbidity measurements and red squares indicate potential outliers. A relationship between turbidity and suspended sediment concentration is also made from the physical sediment samples (Figure 7). We often use a log transform of this data to control the intercept. Physical water quality samples include ISCO, ISO and grab samples. We also create other data relationships that are used for data verification and may be used in data processing. Data Validation and Correction Data in the continuous records is corrected as needed to remove outliers or spikes that appear to be anomalies of the data collection process. See Figure 9 for an example of a corrected data set. Missing data is filled using a variety of techniques at the discretion of the data processor. Data may be filled from physically measured data, interpolated between recorded data, or reconstructed from another site best matched to that site. It is HRC s norm to inspect every data record and to not leave any gaps in the continuous file between the official dates of operation for the season. 17 P age

17 Figure 7. Example relationships between measured lab turbidity (NTU) and SSC (mg/l) at West Branch Railroad Gulch (Station 683). Different shapes in the scatterplot indicate unique turbidity/concentration relationships during distinct storm events throughout the water year. A sediment load is calculated for each of these events which are totaled to estimate annual loading. Each 15-minute turbidity and depth record has a 3 digit quality code added to the data set. The first digit codes the status of the original data, the second digit indicates the method of correction, if any, and the third digit indicates the data manager s confidence in the final data value. A code of 111 indicates original data with no corrections. In our current coding system, a value of 432 would probably be assigned to most of the repaired spikes shown in Figure 8 (a correction is apparent when the raw data value, e,g. tan for turbidity, does not match the validated value, brown). This code indicates, instrument fouling, fixed by interpolation, with good confidence. When the turbidity value can be adjusted by a physical sample collected at the same time, it is rated 481, indicating fouling, filled by direct physical measurement, with confidence equal to original data. The data quality codes remain with the intermediate and final data sets and should be utilized by anyone using HRC data to appropriately evaluate any interpretations in consideration of whether they arise from original or corrected data. 18 P age

18 Figure 8. Example corrected hydrologic data garnered from West Branch Railroad Gulch (Station 683). In the standard data set provided by HRC, the SSC value in each data line is computed from the annually composited Lab turbidity/ssc relationship illustrated in Figure 7. In this relationship, all observations for the year are grouped. In some cases these groupings are based on individual storm events (which may differ) and/or by rising and falling discharge limbs (which do differ). These decisions are indicated in the data file and are made on a site-by-site basis depending on the trends observed in the data. Instantaneous discharge and suspended sediment concentration are translated to volumes and weights by summing over the time intervals of each data line. Total sediment load is a function of suspended sediment concentration times the volume of water. Sediment loads reported here are computed for generally the same interval of time for all stations, some slight differences may be present between stations according to start and end monitoring dates. 19 P age

19 HY 2015 Data Summary A QAQC data file was created for each station for the 2015 hydrologic year. These files contain summary statistics, plots of continuous data, turbidity, stage, and SSC regression models, turbitiy duration curves, turbidity exceedance probabilities and rating data. If sediment loads were calculated for individual storm events, summary tables are presented that offer load totals over the course of the water year. A comment section is provided in each file that offers a brief overview of the water year by the data manager as it pertained to that station. As this is a considerable amount of data, each QAQC file has been stored on CD s that are to accompany this report. Please reference these data files for a complete data summary of each monitoring station. Due to staff turnover in HY 2015, HRC hired an outside contractor to complete QAQC analysis for ten monitoring stations (500, 502, 504, 505, 506, 517, 523, 526, 527, and 528). Data analysis from these stations was validated and approved by the current staff hydrologist. Because of this the formats of these QAQC files may be slightly different than the rest of the monitoring stations but the same data is made available. A brief summary of sediment and discharge results from each station is provided in Table P age

20 Table 8. Summary of annual sediment load and discharge from HRC hydrologic monitoring stations during hydrologic year Data are provisional. Station Number Station Name Watershed Upstream Drainage Area (km 2 ) Total Sediment Load (Mg) Total Sediment Load (Mg/km2) Peak Discharge (cms) Peak Discharge (cms/km2) 188 South Fork Elk River Elk Mainstem Elk River Elk South Fork Elk River Elk North Fork Elk River Elk Bridge Creek Elk North Fork Elk River Elk Tom s Gulch Elk Little South Fork Elk River Elk West Branch Railroad Gulch Elk East Branch Railroad Gulch Elk Beck's Tributary Freshwater Mainstem Freshwater Creek Freshwater Cloney Gulch Freshwater Graham Gulch Freshwater South Fork Freshwater Creek Freshwater Mainstem Freshwater Creek Freshwater Upper mainstem Freshwater Creek Freshwater McCready Gulch Freshwater Little Freshwater Creek Freshwater Bear Creek Lower Eel P age

21 References HRC, WOP-01, Site Monumenting and Documentation, Scotia Pacific Company Scotia, CA. HRC, WOP-02 Gaging streams for estimating discharge, Scotia Pacific Company, Scotia, CA. HRC, WOP-03, Hydrologic Station Instrumentation methodology, Scotia Pacific Company, Scotia, CA. HRC, WOP-04, Water quality grab sampling for sediment and field turbidity measurement, WOP-04, Scotia Pacific Company, Scotia, CA. HRC, WOP-05, Laboratory analysis of suspended sediment, Scotia Pacific Company, Scotia, CA. HRC, WOP-57, Laboratory analysis of suspended sediment, using electronic data collection methods, Pacific Lumber Company, Scotia, CA HRC, WOP-19, Physical infrastructure of a hydrologic station, Pacific Lumber Company, Scotia, CA. HRC, Report of waste discharge Elk River, Scotia Pacific Company, Scotia, California. HRC, Report of Waste Discharge Freshwater Creek, Pacific Lumber Company, Scotia, California. HRC Streamflow and Sediment Monitoring Plan Freshwater Creek Watershed Waste Discharge Permit NCRWQCB R Vs. 1.1 U.S. EPA Guidance for the data quality objectives process EPA QA/R-4. EPA/600/R- 96/055. Office of Environmental Information, Washington, D.C. March U.S. EPA EPA Requirements for Quality Assurance Project Plans EPA QA/R-5. EPA/240/B-01/003. Office of Environmental Information, Washington, D.C. March U.S. EPA Guidance for preparing Standard Operating Procedures EPA QA/R-6. EPA/240/B-01/004. Office of Environmental Information, Washington, D.C. March P age

22 Appendices A. Data validation codes 23 P age

23 Appendix A. Validation Codes for HY 2015 Raw data quality rating codes Type of data recovery or correction codes Quality of data recovery rating codes 0 No Data Recorded 0 Not Assigned 0 No data to rate 1 Good 1 No action necessary 1 Original Data 2 Questionable 2 Data questionable, but maintained 2 Good 3 Equipment Limit 3 Interpolation 3 Fair 4 Error: Equipment fouled 4 Reconstruction 4 Poor 5 6 Error: Equipment maintenance 5 Adjustment 5 Error: Equipment malfunction 6 Smoothing 6 No Recovery Possible Quest ionable but maint ained 7 Error: Equipment calibration error 7 Regression 7 Not Assigned 8 Error: Unknown 8 Filled from Physical Samples 8 Not Assigned measurements 9 being taken affecting readings 9 Other 9 Other 24 P age