PROGRAMS AND PLANS--Correction to Quality of Water Branch Technical Memorandum 81.23 In Reply Refer To: October 9, 1981 EGS-Mail Stop 412 Memorandum To: Distribution From: Chief, Quality of Water Branch, Reston, VA Subject: PROGRAMS AND PLANS--Correction to Quality of Water Branch Technical Memorandum 81.23 Some errors and sources of misunderstanding have been found on page 5 of the subject Technical Memo. Please replace page 5 of the original with the new page 5 attached. R. J. Pickering Attachment WRD Distribution: A, B, S, FO, PO. 5 constituent, dissolved from constituent, solids, residue dry deposition = dissolved / on evaporation X 1,000,000 (mg/kg or ug/kg) = [mg/L or ug/L) / mg/L] X 1,000,000 constituent, total, in constituent, solids, residue dry deposition = total . / on evaporation X 1,000,000 (mg/kg or ug/kg) = [(mg/L or ug/L) / mg/L] X 1,000,000 constituent, constituent, constituent, insoluble in total, in dissolved from dry deposition = dry deposition - dry deposition (mg/kg or ug/kg) = [mg/kg or ug/kg) - (mg/kg or ug/kg)] Parameter codes for the enclosed list of constituents have been received from EPA. Additional codes will be requested on a need basis. Constituents marked with an asterisk (*) will not be stored but will be computed upon request for output purposes. The list below does not include codes for insoluble or total forms of nitrate, nitrite, nitrate plus nitrite, chloride, sulfate, carbonate, or bicarbonate, because these constituents are assumed to be completely dissolved out of a sample when it is exposed to water as is done in the field preparation procedure. R. J. Pickering Chief, Quality of Water Branch Attachment Key Words: Water Quality, Information, Data Handling, Sampling, Atmospheric Deposition, Acid Rain WRD Distribution: A, B, S, FO, PO. Superseded Memoranda: Supersedes Quality of Water Branch Technical Memorandum 81.07. In Reply Refer To: September 23, 1981 EGS-Mail Stop 412 QUALITY OF WATER BRANCH TECHNICAL MEMORANDUM NO. 81.23 Subject: PROGRAMS AND PLANS--Field collection and data processing procedures for atmospheric deposition samples This memo supersedes Quality of Water Branch Technical Memorandum 81.07. The collection and analysis of atmospheric deposition samples are becoming more prominent parts of the WRD water-quality program as evidenced by the Urban Hydrology Studies Program, the acid-rain thrust, and an increasing number of State cooperative programs requesting such data. The state of knowledge in data collection and interpretation techniques is, however, limited and the subject of much controversy, especially in the case of dry deposition. Despite such limitations, samples have been and will continue to be collected. It is imperative that, to the extent possible, a set of guidelines be provided for the procedures to be followed in processing samples in the field and storing the data in the computer. An initial set of guidelines is provided in this memorandum. Modifications are likely as new information is gained. Atmospheric deposition is operationally divided into two components, wet deposition (rain, snow, fog, dew) and dry deposition (particulates, aerosols, gases). The distribution of constituent concentrations in wet deposition relative to elevation, proximity to sources of chemical constituents, and time during an event are not very well understood at the present time. However, it is commonly held that the load of a given constituent falling on a watershed in wet deposition can be measured with acceptable accuracy by a limited number of samplers located throughout the watershed. The sampling precision currently is being examined in several experiments. Systematic relations between location parameters and composition have not yet been developed, but research on this subject is being conducted by a number of organizations. It is hoped that quantitative guidelines on sampler location will be available within a few years. The collection and interpretation of wet-deposition data are fraught with uncertainties and problems, but the collection and interpretation of dry deposition data are fraught with even more uncertainties and problems. The amount of dry deposition collected in the type of collector used by the Survey and the concentrations of constituents in this material are known to vary widely even between closely-spaced samplers. It is uncertain what fraction of the dry-deposition sample collected by present-day techniques represents new material entering the watershed. It may be that the material in the collector represents mostly those larger-sized particles of local origin that move along within a few meters of the ground. In addition, the rate of accumulation of dry deposition is probably not constant over the interval of collection. There is evidence that equilibrium is achieved between material moving into and out of the collector. Until these problems are resolved, a dry deposition sample must serve as only a qualitative indicator of the magnitude of ambient atmospheric sources rather than a quantitative measure of deposition over a watershed. COLLECTORS Wet-deposition and dry-deposition samples can be collected with the Aerochem Metrics Model 301 sampling device or equivalent. Placement of the device will depend on the nature of the information desired. A sampler placed low to the ground will tend to collect the larger-sized particles that reflect predominantly local characteristics, whereas samplers placed at greater heights will collect particles that have presumably been transported longer distances. The generally accepted placement criteria calls for the top of the collector to be located 3 +/- 1 m above the ground. In general, an unobstructed zone should surround the sampler with no large objects protruding (or standing) above a line- of-sight projected at an angle of 30 degrees above the horizontal to minimize contamination from leaves, droplets blown from tree surfaces, etc. Some protection from excessive winds is desirable and is best provided by trees sufficiently far away as to not interfere with the unobstructed zone described above. The actuating mechanism for moving the coverplate over the dry deposition collector should be checked frequently and adjusted to insure that the dry collector receives a minimal amount of wet deposition. On the Aerochem Metrics Model this can be done preferably by decreasing or increasing the high temperature setting to increase or decrease, respectively, the sensitivity. Under certain circumstances, the sensitivity can be increased by applying pressure to the grid covering the cover plate. The reduced distance between the grid and the plate permits a lesser amount of moisture to activate the mechanism. FIELD PROCEDURES Special field procedures are needed for the Urban Hydrology Program to insure compatibility of laboratory results between stream and atmospheric-deposition samples. Specifically, only total and total recoverable analyses will be performed on unfiltered samples of both stream water and atmospheric deposition. All other programs have the options of total and total recoverable analyses on unfiltered samples, dissolved constituent analyses on samples filtered in the field, and calculation (by difference) of concentrations on particulate matter (in mg/L) in wet-deposition samples. Wet-deposition samples can be collected on a storm-event basis or on a fixed-interval basis, depending on the objective of the study, but should be collected no less often than biweekly. Composite samples from minor wet deposition events preceding major storm events may be composited in an urban hydrology study even if the minor events were insufficient to cause runoff. Dry-deposition samples should be removed from the collector on a frequency of not less than once every 2 months, but monthly collections are recommended. If deposition rates are sufficiently large, a higher frequency of collection may be useful in special cases. In any case, adequate material for the analysis of all required constituents within appropriate detection limits must be provided; otherwise, less than detection limit values will have to be reported. This may require some dry runs to determine the minimal amount of material required. The dry-deposition material is removed from the collector by sequential rinsing with small volumes of deionized water (preferably supplied by the Central Laboratory to standardize matrix effects) from a wash bottle containing a known volume of water (250 mL recommended) and alternate scrubbing with a clean flexible spatula made of such material that the introduction of extraneous trace metals or organics is minimized. Before rinsing the walls of the collector, large pieces of organic material, such as leaves and insects, should be removed with tweezers. Samples that have noticeable bird droppings should be discarded, because leaching of bird droppings and other organic material by accidental water in the dry collector could seriously mask the chemistry of the dry-deposition material. Analytical data for all dry- deposition samples should be scrutinized carefully later on for any indication of contamination. The resulting sample will have a water volume which will be the sum of any wet deposition accidentally accumulated in the dry collector (which can be considerable in some cases) during the sampling interval and the volume of deionized water added. The total volume of both the wet- and dry-depostion samples must be determined accurately, preferably by weighing, but an accurate graduated cylinder will suffice. The Ohaus lll9D triple beam scale (about $300) is recommended by the National Atmospheric Deposition Program (NADP). This unit is rugged and can handle up to 10 kg. Once the final wet- or dry-deposition sample is obtained and the volume accurately determined, process the sample as follows: 1. Use cone splitter to obtain uniform subsamples for each bottle type required by the laboratory, including an extra bottle for field analysis of pH, conductivity, and alkalinity, if needed. 2. For each dry-deposition sample collected, include a separate bottle for a total solids determination, needed for calculation of constituent concentration by weight of dry deposition. 3. Perform field measurements as usual. If the sample has a conductivity of 50 umhos or less, follow the procedure outlined in QW Branch Technical Memo 80.19 for determination of pH in low conductivity waters. 4. Unfiltered samplesQacidify, preserve, or chill appropriate bottles as you would a regular 'whole-water" stream sample. Specify appropriate laboratory codes on log-in form. 5. Filtered samplesQuse a 0.45 um Millipore filter (or equivalent); prerinse with 200 mL distilled or deionized water; filter; acidify, or add preservative and chill as normally for stream water samples. 6. The sample log-in sheet and any field-note sheet should contain the following information to be used by the laboratory to process the samples and input the data into the computer. a. begin time and date of collection b. end time and date of collection c. volume of deionized water added to dry-deposition sample d. resulting volume of dry-deposition sample (sample plus deionized water added) e. volume of wet deposition collected f. sample type (wet or dry deposition) g. collection areas of wet- and dry-deposition collectors h. wind velocity (WATSTORE code 00035), optional 7. Flag the sample as atmospheric deposition on the log-in form and on the bottle label. The project leader should develop a schedule of lab analyses ahead of time and specify the priority of analyses to be performed when sample volume is small. The Central Laboratories System will develop a lab schedule for atmospheric deposition to be offered in the next Laboratory Services Catalog. DATA PROCESSING Additional values for WATSTORE parameter code 72005 (sample- source code) have been assigned so that an atmospheric- deposition sample can be uniquely identified as such, thus allowing the sample-source code to be used as a retrieval parameter. The value for wet deposition is 1001 and the value for dry deposition is 1002. Additional site-specification data can be supplied in the station-name field of the WRD Station Header File. Wet- and dry-deposition samples will be stored as separate analyses in the Water-Quality File. Analytical results for wet-deposition samples will be stored in the computer using the same parameter codes and units as stream samples. For dry-deposition samples, new parameter codes have been obtained (see attached list). The units are mass of constituent per mass of total dry-deposition material, similar to the units used for constituents in stream-bottom material. Because dry-deposition samples are delivered to the laboratory as solutions, it will be essential that one of the analyses for each sample be solids, residue at 105 DEG C, total in dry deposition." The laboratory computer will compute the correct constituent concentration using the concentrations of the individual constituent and total solids in the sample solutions supplied to the laboratory as follows: constituent, dissolved from constituent, solids, residue dry deposition = dissolved / on evaporation X 1000 (mg/kg / ug/kg) = [(mg/L / ug/L) / mg/L] constituent, total, in constituent, solids, residue dry deposition = total / on evaporation X 1000 (mg/kg / ug/kg) = [mg/L / ug/L) / mg/L] constituent, constituent, constituent, insoluble in total, in dissolved from dry deposition = dry deposition - dry deposition (mg/Kg / ug/kg) = [(mg/kg / ug/kg) - (mg/kg / ug/kg)] Parameter codes for the enclosed list of constituents have been received from EPA. Additional codes will be requested on a need basis. Constituents marked with an asterisk (*) will not be stored but will be computed upon request for output purposes. The list below does not include codes for insoluble or total forms of nitrate, nitrite, nitrate plus nitrite, chloride, sulfate, carbonate, or bicarbonate, because these constituents are assumed to be completely dissolved out of a sample when it is exposed to water as is done in the field preparation procedure. R. J. Pickering Chief, Quality of Water Branch Attachment Key Words: Water Quality, Information, Data Handling, Sampling,Atmospheric Deposition, Acid Rain WRD Distribution: A, B, S, FO, PO. Superseded Memoranda: Supersedes Quality of Water Branch Technical Memorandum 81.07. PARAMETER CODES TO BE REQUESTED 1001 wet deposition - sample source code (72005) value 1002 dry deposition - sample source code (72005) value 82284 collector efficiency, wet deposition, percent 82283 collector efficiency, dry deposition, percent 82468 solids, sum of constituents, dissolved from dry deposition (mg/kg) 82467 solids, sum of constituents, insoluble in dry deposition (mg/kg)* 82466 solids, sum of constituents, total in dry deposition (mg/kg) 82465 solids, residue at 105 DEG C, dissolved from dry deposition (mg/kg) 82464 solids, residue at 105 DEG C, insoluble in dry deposition (mg/kg)* 82463 solids, residue at 105 DEG C, total in dry deposition (mg/kg) 82462 nitrogen, nitrate, dissolved from dry deposition (mg/kg as N) 82461 nitrogen, nitrate, dissolved from dry deposition (mg/kg as N03)* 82460 nitrogen, nitrite, dissolved from dry deposition (mg/kg as N) 82459 nitrogen, nitrite, dissolved from dry deposition (mg/kg as N02)* 82458 nitrogen, nitrite + nitrate, dissolved from dry deposition (mg/kg as N) 82457 nitrogen, ammonia, dissolved from dry deposition (mg/kg as N) 82456 nitrogen, ammonia, dissolved from dry deposition (mg/kg as NH4)* 82455 nitrogen, ammonia, insoluble in dry deposition (mg/kg as N)* 82454 nitrogen, ammonia, insoluble in dry deposition (mg/kg as NH4)* 82453 nitrogen, ammonia, total in dry deposition (mg/kg as N) 82452 nitrogen, ammonia, total in dry deposition (mg/kg as NH4)* 82451 nitrogen, ammonia + organic, dissolved from dry deposition (mg/kg as N) 82450 nitrogen, ammonia + organic, insoluble in dry deposition (mg/kg as N)* 82449 nitrogen, ammonia + organic, total in dry deposition (mg/kg as N) 82448 nitrogen, organic, dissolved from dry deposition (mg/kg as N)* 82447 nitrogen, organic, insoluble in dry deposition (mg/kg as N)* 82446 nitrogen, organic, total in dry deposition (mg/kg as N)* 82445 nitrogen, dissolved from dry deposition (mg/kg as N)* 82444 nitrogen, insoluble in dry deposition (mg/kg as N)* 82443 nitrogen, total in dry deposition (mg/kg as N)* 82442 phosphorus, dissolved from dry deposition (mg/kg as P) 82441 phosphorus, dissolved from dry deposition (mg/kg as P04)* 82440 phosphorus, insoluble in dry deposition (mg/kg as P)* 82439 phosphorus, insoluble in dry deposition (mg/kg as P04)* 82438 phosphorus, total in dry deposition (mg/kg as P) 82437 phosphorus, total in dry deposition (mg/kg as P04)* 82436 phosphorus, orthophosphate, dissolved from dry deposition (mg/kg as P) 82435 phosphorus, orthophosphate, dissolved from dry deposition (mg/kg as P04)* 82434 phosphorus, orthophosphate, insoluble in dry deposition (mg/kg as P)* 82433 phosphorus, orthophosphate, insoluble in dry deposition (mg/kg as P04)* 82432 phosphorus, orthophosphate, total in dry deposition (mg/kg as P) 82431 phosphorus, orthophosphate, total in dry deposition (mg/kg as P04)* 82430 sodium, dissolved from dry deposition (mg/kg) 82429 sodium, insoluble in dry deposition (mg/kg)* 82428 sodium, recoverable from dry deposition (mg/kg) 82427 potassium, dissolved from dry deposition (mg/kg) 82426 potassium, insoluble in dry deposition (mg/kg)* 82425 potassium, total recoverable from dry deposition (mg/kg) 82472 calcium, dissolved from dry deposition (mg/kg) 82471 calcium, insoluble in dry deposition (mg/kg)* 82470 calcium, total recoverable from dry deposition (mg/kg)* 82473 magnesium, dissolved from dry deposition (mg/kg) 82474 magnesium, insoluble in dry deposition (mg/kg)* 82475 magnesium, total recoverable from dry deposition (mg/kg) 82476 chloride, dissolved from dry deposition (mg/kg) 82477 sulfate, dissolved from dry deposition (mg/kg) 82478 carbonate, dissolved from dry deposition (mg/kg) 82479 bicarbonate, dissolved from dry deposition (mg/kg) 82484 carbon, organic, dissolved from dry deposition (mg/kg as C) 82485 carbon, organic, insoluble in dry deposition (mg/kg as C)* 82483 carbon, organic, total in dry deposition (mg/kg as C) 82480 carbon, inorganic, dissolved from dry deposition (mg/kg as C) 82481 carbon, inorganic, insoluble in dry deposition (mg/kg as C)* 82482 carbon, inorganic, total in dry deposition (mg/kg as C) 82486 lead, dissolved from dry deposition (ug/kg) 82487 lead, insoluble in dry deposition (ug/kg)* 82488 lead, total recoverable from dry deposition (ug/kg) 82489 cadmium, dissolved from dry deposition (ug/kg) 8249~ cadmium, insoluble in dry deposition (ug/kg)* 82491 cadmium, total recoverable from dry deposition (ug/kg) 82492 copper, dissolved from dry deposition (ug/kg) 82493 copper, insoluble in dry deposition (ug/kg)* 82494 copper, total recoverable from dry deposition (ug/kg) 82495 zinc, dissolved from dry deposition (ug/kg) 82496 zinc, insoluble in dry deposition (ug/kg)* 82497 zinc, total recoverable from dry deposition (ug/kg) 82498 chromium, dissolved from dry deposition (ug/kg) 82499 chromium, insoluble in dry deposition (ug/kg)* 82500 chromium, total recoverable from dry deposition (ug/kg) 82501 iron, dissolved from dry deposition (ug/kg) 82502 iron, insoluble in dry deposition (ug/kg)* 82503 iron, total recoverable from dry deposition (ug/kg) 82504 arsenic, dissolved from dry deposition (ug/kg) 82505 arsenic, insoluble in dry deposition (ug/kg)* 82506 arsenic, total in dry deposition (ug/kg)