MD DNR Chesapeake Bay Tributary Water Quality Monitoring Program 2019

QUALITY ASSURANCE/QUALITY CONTROL Maryland Department of Natural Resources followed specific procedures to ensure that the Tributary component of the Chesapeake Bay Water Quality Monitoring Program design was properly implemented and managed with sufficient accuracy, precision and detection limits. Accuracy (closeness to the true value) of collected data was controlled and assured by proper use, calibration and maintenance of both field and laboratory equipment for the measurement of physical and chemical parameters. The procedures used to control and assure the accuracy of field measurements involved the calibration of field instruments, the verification of calibrations, and equipment maintenance. Most of the details of how data acquired with YSI sondes and Hydrolab sondes were quality assured and quality controlled are described in the process description elements in the Lineage portion of this metadata record. Daily quality control checks which included the running of blanks and standards were used to control and assure laboratory accuracy. Accuracy of Chesapeake Biological Laboratory, Nutrient Analytical Services Laboratory (CBL NASL) results was also assessed through DNR's participation in the Chesapeake Bay Coordinated Split Sample Program (CSSP) a split sampling program in which five laboratories involved in Chesapeake Bay monitoring analyze the coordinated split samples. CSSP was established in June 1989 to establish a measure of comparability between sampling and analytical operations for water quality monitoring throughout the Chesapeake Bay and its tributaries. DNR followed the protocols in the Chesapeake Bay Coordinated Split Sample Program Implementation Guidelines (EPA 1991) and its revisions. Split samples were collected quarterly. Results were analyzed by appropriate statistical methods to determine if results differed significantly among labs. If a difference occurred, discussions began regarding techniques and potential methods changes to resolve discrepancies. ADDITIONAL COMMENTS January 2019: A pycnocline did not exist at station EE3.2 and the above pycnocline and below pycnocline samples were collected from 1/3 and 2/3 of total station water column depth. Overnight rain fell the night before stations WXT0001, TF1.4 and TF1.3 were sampled. The Secchi disk depth measurement at station TF1.3 exceeded the station total water column depth. "Windowpane" ice was noted at station ET1.1. Station EE2.1 bottom and below pycnocline water samples were collected from the same bottle. February 2019: Due to the absence of pycnoclines at stations EE3.1, EE3.2, ET5.2 and EE2.1, above and below pycnocline samples were collected from 1/3 and 2/3 of total station water column depths. March 2019: There were no pycnoclines at stations RET2.4, EE3.2 and EE2.1. Therefore, water samples were collected at 1/3 and 2/3 total station depths. April 2019: Thunderstorms occurred the night before water samples were taken at stations ET6.1, ET41.1 and WIW0141. The Secchi disk depth measurement at station TF1.3 exceeded the station total water column depth. Water samples were collected at 1/3 and 2/3 of station total depths, due to lack of pycnoclines, at the following stations: RET2.4, T6.1, WIW0141, ET10.1, ET5.2, EE2.1, EE3.1 and ET4.2. May 2019: The station LE2.2 dissolved oxygen readings at 6 m - 11 m were double-checked. Rain fell the night before stations ET1.1, ET2.1 and ET2.3 were sampled. There were morning showers prior to sampling operations at stations TF1.3, TF1.4 and WXT0001. The Secchi disk depth measurement at station TF1.3 was greater than the station total water column depth. Water quality samples at stations EE2.1, EE3.1, ET1.1, ET2.1, ET2.3, ET4.2, ET5.2, LE2.2 and RET2.4 were collected at 1/3 and 2/3 of station water column depths. June 2019: Heavy early morning rain fell prior to sampling at stations ET1.1, ET2.1, ET2.2 and ET2.3. Similarly, there were morning storms at stations WT1.1, WT2.1, WT3.1 and WT4.1. The Secchi disk depth measurement at station TF1.3 was greater than the station total water column depth and a sheen and scum were noted in field sheet comments. Stations EE2.1, EE3.1, EE3.2, ET5.2 and RET2.4 above pycnocline and below pycnocline samples were collected at 1/3 and 2/3 station total depths because there were no pycnoclines. July 2019: The pH sensor used for stations LE1.1, LE1.2, LE1.3, LE1.4, RET1.1, TF1.5, TF1.6 and TF1.7 failed post calibration tests. The odor of hydrogen sulfide was observed in the station LE1.1 sample water. August 2019: The water at station ET3.1 was green and a plankton sample containing Microcystis was collected. Mats of seaweed were floating down river at station ET4.1. The above pycnocline and below pycnocline water samples at station LE2.2 should have been collected at 1 m deeper depths. There were no pycnoclines at stations RET2.4, ET5.2, EE3.1, EE3.2 and EE2.1 and above pycnocline and below pycnocline samples were collected from 1/3 and 2/3 of total station water column depths respectively. The bottom sample at station EE1.1 had a strong hydrogen sulfide odor. The station EE1.1 bottom and below pycnocline samples were both collected at 11.6 m. Rain showers preceded sampling at stations EE1.1, ET1.1, ET2.3 and ET4.2. The Secchi disk depth was greater than total station depth at station TF1.3. September 2019: No pycnoclines were extant at stations RET2.4, ET4.2, ET5.2, EE2.1, EE3.2 and EE3.1 therefore above pycnocline and below pycnocline samples were taken from 1/3 and 2/3 of total station depths. Stations LE2.2 and EE1.1 bottom and below pycnocline samples were both collected the same depths. Morning showers preceded sampling at stations EE1.1 and ET4.2. A dip in dissolved oxygen at 9 m was noted at station LE1.2. October 2019: There were no pycnoclines at stations EE1.1, EE3.1, EE3.2, ET4.2, ET5.2 and RET2.4 and above pycnocline and below pycnocline samples were taken from 1/3 and 2/3 of total station depths. November 2019: The Secchi disk measurement at station TF1.3 was greater than the total station depth. The station ET4.2 bottom and below pycnocline samples were collected at 9.7 m depth. No pycnoclines were found at stations ET5.2, RET2.4, EE3.1 and EE3.2 so above pycnocline and below pycnocline samples were taken from 1/3 and 2/3 of total station depth. December 2019: The station TF1.3 Secchi disk depth measurement was made from the pier and was greater than total station depth. Pycnoclines were nonexistent at stations EE2.1, EE3.1, EE3.2, ET5.2 and LE2.2 and above pycnocline and below pycnocline samples were taken at 1/3 and 2/3 of total station depths. Rain fell the night before sampling at stations ET10.1, ET6.1, MAT0016, RET2.1, RET2.2, RET2.4, TF2.1, TF2.3, WIW0141 and XFB1986. Rain fell the morning before station EE2.1 was sampled. The pH 10 post-calibration results for the sonde used at stations ET3.1 and ET4.1 were outside acceptable limits.