Discharge Monitoring Reports (DMRs) Helpful Tips for completing DMRS

What is a DMR? Routine report submitted (usually monthly) by the permittee to the Department which contains analysis or results of calculations derived from self-monitoring analytical data. Typically contains three parts Part A (Main Portion - Summary) Part B (Daily Results) Part D (Ground Water Data) May be more than one set of DMRs/facility

“Helpful Tips”: Background DEP developed a “Tips” document Aug. 2003, to assist owners/operators in avoiding common mistakes when completing DMRs for submittal Help ensure consistency Also, to assist internal staff that routinely review these reports.

Important facts to remember ALL sample results obtained, even if there are more analysis performed than required, must be reported provided they are analyzed using the proper method. “Tips” was developed to help clarify and assist. “Instructions for Completing the Wastewater DMR” should have come with your original DMR. These “Instructions” should be followed foremost.

Helpful Tips: Topics Covered Reporting data from continuous monitoring Strip Chart Computerized data Significant Figures BDL and other data qualifiers Daily Data defined Reporting and calculating data for: Flow Water Quality data Loading data Fecal Coliform Toxicity Data for new facilities

Daily Data Rule 62-620.200(10), F.A.C., defines “daily discharge” as: the discharge measured during a calendar day for any 24-hour period that reasonably represents the calendar day for purposes of sampling.

Daily Data (cont’d) Typically, the calendar day of 12:00 midnight – 11:59 p.m. is used. However, a permittee may specify a 24-hour period that corresponds to staffing shifts as their reporting day, provided it is consistent for purposes of reporting and should not vary from one day to another.

Reporting Flow Data Daily Flow Daily Flow amounts, or daily totals, should be entered on Part B of the DMR in the units specified on the DMR If no discharge occurred, enter “0” for that day’s flow amount.

Reporting Flow Data (cont’d) Monthly Average Flow This is normally reported on Part A. A monthly average for flow is calculated by summing the daily flow amounts and then dividing by the number of days in the month (include days in which there was no discharge).

Reporting Flow Data (cont’d) Annual Average Flow Reported on Part A, expressed in units of MGD Rule definition is to total the last 365 consecutive days of flow and divide that total by 365. For practical purposes it may be calculated as the rolling arithmetic mean of the last 12 monthly averages.

Water Quality Data Unlike Flow, averages for water quality data are based on a sum of the numerical results divided by the number of observations. (days of no discharge are not factored into these calculations).

Water Quality Data (cont’d) Daily Data Reported on Part B. If your permit requires daily monitoring for a parameter, an appropriate sample should be taken on each day there is a discharge. Reporting Max and Min. No calculations required to report these values Review the daily data on Part B for the entire month Select highest value for Max, lowest value for Min

Water Quality Data (cont’d) Weekly Data If your permit requires a sample frequency of weekly, then at least one sample on a day of discharge during that week should be collected. It is recommended that a sample at the first occurrence of a discharge be collected to ensure that required sampling is met. Recommended Week: Sunday to Saturday (consistency is important)

Water Quality Data (cont’d) What about Partial Weeks? For example, February 2004 ends on a Sunday. If following the recommended week (Sun-Sat); the daily results for Sun, Feb 29th should be entered on Part B and used in the monthly calculations for the month of February. when calculating weekly results the data collected on this day should be included for the first week of March, 2004.

Water Quality Data (cont’d) What if only one sample/month? Report that value as the Monthly Average and Maximum (or Minimum, whichever applies). Similarly samples collected once/week would be reported as the weekly average.

Water Quality Data (cont’d) Calculating Annual Average Calculated as the arithmetic mean of the 12 monthly averages collected during the last consecutive 12 month period. If “no discharge” reported for one (or more) of those 12 months, then base the average on the number of months with a discharge.

Loading Data Calculated by combining concentration data with flow data. Limits are primarily expressed in three ways: Monthly average, Daily average (based on number of days of discharge) and Daily Maximum Expressed in terms of pounds per day (lbs/day). [lbs/day] = [8.34]*[flow in mgd]*[concentration in mg/L] Referred to “Tips” for examples

Reporting Fecal Coliform Data Daily Values (Max) Percent less than detection Monthly Averages geometric mean monthly median Annual Average which reporting requirement generally depends on level of dis-infection and/or monitoring frequency.

Fecal Coliform: Daily Data Recorded on Part B Observations less than detection should be reported as “<1” (if MF technique) or “<2.2” (if MPN technique) On Part A record the Maximum as the highest value recorded on Part B.

Fecal Coliform: %<detection Count the number of daily observations that the value was below detection. Divide this by the total number of fecal coliform observations for the month. Multiply by 100% Round to nearest whole integer.

Fecal Coliform: 90th percentile If permit limit is that no more than 10% of the samples during a 30 day period shall exceed a certain value, the 90th percentile will be reported on the DMR. Example how to calculate: 10 samples with fecal results 8,4,5,20,7,6, 34, 22, 4, 18 List values in ascending order: 4, 4, 5, 6, 7, 8, 18, 20, 22, 34 Multiply the number of samples taken by 0.9: 0.9*10 = 9 Report the 9th value in the series as the 90th percentile: 22

Fecal Coliform: Monthly Geo Mean Rule 62-600.200(33), F.A.C., defines it as the nth root of the product of n numbers. In other words, in order to calculate the geometric mean of n observations, each of the n values would be multiplied together and the resulting product will be raised to the 1/nth power Refer to “Tips” for examples on how to calculate.

Fecal Coliform: Monthly Median Instead of a monthly geometric mean limit, may require a monthly median: Example how to calculate: 10 samples with fecal results 8,4,5,20,7,6, 34, 22, 4, 18 List values in ascending order: 4, 4, 5, 6, 7, 8, 18, 20, 22, 34 Find the middle value. In this example there are two middle values, so average them: (7*8)/2 = 7.5. If there are an odd number of values, you won’t need to find the average. Report the median as 7.5.

Fecal Coliforms: Annual Average Calculated as the arithmetic mean of the 12 monthly averages (either geometric or median) collected during the last consecutive 12 month period.

Reporting “Too Numerous to Count” When a facility reports a value of “TNTC”, this value is translated to “20,000 values/100 mL of sample” for purposes of calculating monthly and annual averages. It is recommended that laboratories use more dilutions to be able to report a value other than “TNTC”. Facilities sampling monthly for fecal may need to consider taking additional samples.

Reporting Toxicity Data Acute Reported as % mortality for a single concentration test. Chronic Reported as percent effluent with “No Observed Effect Concentration” Minimum of two endpoints is measured in each test. Report the most sensitive NOEC value.

Reporting Continuous Monitoring Data Strip Charts: Visually inspect the chart and select highest values as Max and lowest as Min. Daily Averages: Take the reading on the chart at exactly each hour of the day (12AM, 1AM, 2AM, etc) Take the arithmetic average of the 24 values and report the result on Part B as the daily average.

Reporting Continuous Monitoring Data Computerized Data Logging: the computer system should poll the continuous monitoring instrument at frequent and uniformed intervals. time between polls should be no more than 5 minutes. The Max (and/or Min) should be selected from all logged (or polled) values, and recorded on Part B. Arithmetic average calculated based on all logged (or polled) values. If polled once/5 min, 288 values/day.

Significant Figures When reporting averages on your DMR, the same number of significant figures should be shown in the average as is contained in the least precise data point being averaged (i.e., the data point having the smallest number of significant figures)

Below Method Detection In cases where a laboratory result is reported as below a MDL, the value should be averaged using either one-half the MDL, or one-half the corresponding permit limit, whichever is lower. In cases where the result is reported as less than a PQL, but, greater than or equal to the MDL, the lower MDL value should be used for reporting on the DMR and for calculating averages. See example in “Tips” document.

Data Qualifier Codes DMR data qualifier codes help serve as indicators of special circumstances that may be associated with data or results Labs are required to use the data qualifier codes listed in Table 1 of Chapter 62-160, F.A.C. These codes are not to be transferred onto the DMR Only the data qualifier codes listed in the “Instructions” may be used when reporting on the DMR.