How to do Sampling A guide for industrial facilities

Washington State Department of Ecology December 2002 (rev. March 2010) Publication #02-10-071 Acknowledgements The Water Quality Program would like to thank the following individu- als for contributing their hard work and technical knowledge to the 2010 update.

From the Department of Ecology: Jeff Killelea Stephen Golding Elaine Tomita Julie Lowe Dewey Weaver Kurt Baumgarten Kevin Hancock Marc Pacifico Tom Leonard

From Environmental Compliance Tools LLC: Robin Sandell

The Department of Ecology is an equal opportunity agency and does not discrim- inate on the basis of race, creed, color, disability, age, religion, national origin, sex, marital status, disabled veteran's status, Vietnam Era veteran's status, or sexual orientation. To ask about the availability of this document in a version for the visually impaired, call the Water Quality Program at 360-407-6401. Persons with hearing loss, call 711 for Washington Relay Service. Persons with a speech disability, call 877-833-6341. Table of Contents

Introduction ...... page 1

Advance Planning for Stormwater Sampling...... page 2 Deciding What To Sample ...... page 2 Visible Oil Sheen, Zinc, Copper, Turbidity, and pH...... page 2 Selecting a Laboratory to Test Your Sample...... page 2 Contacting the Lab in Advance ...... page 3 Issues you may want to cover with the lab include: ...... page 3 Deciding How You Will Take The Sample ...... page 4 Collecting Total Petroleum Hydrocarbons (TPH)Samples ...... page 5 Determining which Discharges to Sample ...... page 5 Selecting Sampling Points ...... page 7 Obtaining Supplies for Sampling...... page 8

Planning Just Prior to Stormwater Sampling ...... page 9 Being Prepared...... page 9 Choosing When to Sample...... page 9 Check weather forecasts...... page 10

Conducting Sampling at Your Facility ...... page 11 Checklist for Sampling ...... page 11 How to Fill Sample Bottles ...... page 11 Keeping Records ...... page 12 When the Sampled Storm Doesn’t Meet the Required Criteria .....page 13

Special Sampling Considerations ...... page 14 Sampling as Stormwater Discharges from a Pipe into a Receiving Water . . page 14 Sampling from a Manhole ...... page 14 Sampling from a Drainage Ditch or Swale ...... page 15 Sampling Sheet Flow ...... page 15 Sampling from a Stormwater Detention Pond or other BMP ...... page 16

Ecology Wants to Hear from You ...... page 17

Appendix - Proper and Improper Methods of Sampling ...... page 18

References ...... Inside back cover Introduction

he Industrial Stormwater General determining if your existing plan is The purpose of this TPermit requires that your facility adequate, and when implementing or conduct at least quarterly sampling of assessing best management practices guide is to help stormwater and report the sampling (BMPs). those who operate results to Ecology. These require- Some effort is required up front to ments are outlined in the permit un- prepare for sampling in a way that facilities do their der Section S4. General Sampling will meet requirements and provide Requirements. This guide supports useful data. What follows is a step- own sampling. the sampling portion of the general by-step procedure of what you need permit but does not substitute for it. to do to gather and report data that The purpose of this guide is to help will represent the quality of storm- those who operate facilities do their water leaving your facility. The steps own sampling by describing the steps are organized to guide you through and procedures to be followed. This the stormwater sampling process guidance will lead you to be able to from start to finish. sample in a way that will provide you This guidance is an update to and Ecology with meaningful results. “How to do Stormwater Sampling” Sources of pollutants that may en- which was originally developed by ter surface water, sediments, or Ecology’s Environmental Assessment ground water can be identified by Program in 2002. The update was made sampling stormwater discharges. The in accordance with the new Industrial results of sampling will be helpful Stormwater General Permit which be- when developing your Stormwater came effective on January 1, 2010. Pollution Prevention Plan (SWPPP),

Page 1 Introduction Advance Planning for Stormwater Sampling

Deciding what to Sample Turbidity can be measured Before beginning your sampling, you’ll directly in the field using a handheld All facilities must meter, or sampled and analyzed in need to determine the specific pollutants monitor for (water quality parameters) you are re- the lab. You must measure pH in quired to sample and test for. All facili- the field using either a calibrated pH turbidity, pH, zinc, ties must monitor for turbidity, pH, zinc, meter or pH paper rather than send- copper, and the presence of a visible oil ing it to a lab. This is due to the short copper, and a sheen. Your parameters are based on: holding time for pH. You can get visible oil sheen. pH paper from a distributor of scien- uThe standard set of parameters for tific/laboratory supplies or through all facilities, (turbidity, pH, zinc, the same laboratory that will be doing copper and visible oil sheen). your sample analysis. Zinc, copper, u The industrial activities at your and other parameters required by the site, often classified by your facility’s permit (other than turbidity and pH) Standard Industrial Code (SIC Code). are measured by sending bottled sam- uWhether your facility discharges to ples to a laboratory for analysis. an impaired (303 (d) listed) water This is an body. example of an oil sheen at a uAny requirements that apply to storm drain facilities that discharge to water bodies with a water cleanup plan or Total Maximum Daily Load (TMDL). Ecology has listed the required parame- ters for your facility on your Discharge Monitoring Report (DMR) form.

Visible oil sheen, zinc, copper, turbidity, and pH If there is a visible oil sheen at the point of Selecting a laboratory Contact the lab discharge from your facility, you need to to test your sample make note of it on your DMR form. A Having identified the parameters you well ahead of time. rainbow colored sheen on the surface of will need tested, the next step is to se- stormwater may indicate the presence of lect a laboratory to perform the tests. oil. However, not all sheens on the water You are required to select a lab ac- are oil sheens. Some sheens result from credited by Ecology. The lab must be natural processes, such as rotting vegeta- accredited for each analytical method tion or the bacterial breakdown of iron. required by the permit for each pa- How do you tell the difference between rameter. Accreditation assures Ecol- an oil sheen and a naturally occurring ogy that the lab is able to do quality sheen? Try to break up the sheen with a testing using the analytical methods stick. An oil sheen will swirl, elongate, specified under Monitoring Require- and reform. A sheen resulting from a nat- ments in your permit. You can search ural process will typically break up into for an accredited lab on Ecology’s irregular platelets that do not reform and website: www.ecy.wa.gov/ programs/ have a mirror-like appearance. eap/labs/search.html

Advance Planning for Stormwater Sampling Page 2 Ask questions - Contacting the Issues you may want to cover lab in advance with the lab include: your lab can You should contact the lab well ahead uConfirmation that the lab is help you. of time. They will be providing you accredited for the testing methods the with the sampling bottles you’ll need. permit requires. For some water quality parameters, uThe type and size of bottle that will such as Total Petroleum Hydrocarbons be supplied for each water quality (TPH), it is not only desirable but nec- parameter to be sampled and tested. essary to collect the sample directly u into a specially-cleaned container, so How full to fill the bottle. you will need to have bottles from the uAny safety concerns with materials lab on hand before you sample. You supplied by the lab. can also ask your lab to send narrow- uWhat you need to know about range pH paper (with a resolution not preserving your samples: Make a note greater than ± 0.5 SU) along with your of the parameters for which bottles will sample bottles. have preservative inside. For some tests, Please note that not all facilities a preservative is necessary. The are required to collect TPH samples. preservative is a substance that stabilizes Refer to page 26 of the permit for a certain chemicals at the time of sampling list of industrial activities for which so that a valid test can be done later. It is the permit requires TPH samples. critical that you use the correct bottles Discuss with the lab the analytical because tests requiring preservative will methods they will use, as specified in not be valid without the correct the sample parameter tables included preservative. In some cases, the wrong in S5. A and S5. B of the general preservative will interfere with a test. It permit (pages 24 and 25). The lab will is important not to lose the preservative provide you helpful information and that comes in the bottles supplied by the explanations that go beyond the lab. The table to the left provides scope of this guide. If you must meet information for preserving zinc, effluent limits listed in “S5.C, Storm- turbidity, and copper samples. water Discharges Subject to Effluent uThe kind of labels the lab will Limitation Guidelines” you should supply for the bottles and how the carefully review them with the lab. labels should be filled out. The labels or tags you use to identify the Typical Sampling Information samples you take must be waterproof, and if you write on them, the writing Minimum Holding must be waterproof also. Parameter Bottle Type Sample Preservation Time u Required Get a Chain of Custody (COC) form from the lab and go over how to 500 mL wide- Turbidity 100 mL 48 hours Cool to 4º C complete these before sampling the mouthed poly first time. 1liter (L) uA description of forms or other bottle HNO3 to pH<2 paperwork to submit to the lab with Total Zinc cleaned 500 mL 6 months the samples and how to fill them out. according to Cool to 4º C protocol uWhether the lab will supply pH paper as well as sample bottles, tags or Copper, Dependent labels for the bottles, and blank forms. Total 500 mL HDPE 6 months HNO3 to pH<2 on the lab Recoverable uHow bottles and other supplies from the lab will be delivered to you.

Page 3 Advance Planning for Stormwater Sampling uThe holding times for each water Deciding How You Will quality parameter to be sampled and Take The Sample tested. A holding time is the Section S4.B.1(d) on page 22 of the maximum time allowed between Industrial Stormwater General Permit taking the sample and doing the lab states that a grab, time-proportionate, analysis. If you exceed holding time, or flow proportionate sample may the sample analysis is not acceptable. be taken. A grab sample is a single uHow and when you will deliver sample “grabbed” by filling up a samples to the lab. Plan with the lab container, either by hand or with the how you will get the samples to them container attached to a pole. It is the in time to begin analysis before the simplest type of sample to collect and parameter with the shortest holding it is expected that most permit holders time reaches that holding time. The will choose to collect grab samples. fastest way to deliver samples to the Ecology provides standard operating lab may be in person, but it may be procedures (SOP) for obtaining grab possible to ship samples (cooled in samples, along with other sampling picnic coolers) and still meet holding guidance, at http://www.ecy.wa.gov/ times. If you deliver samples in programs/eap/quality.html. person, you can pick up bottles and As we will discuss in the next sec- supplies for the next quarter at the tion, Total Petroleum Hydrocarbons same time. The table (page 3) shows (TPH) samples must be collected as typical sampling information for the grab samples. Some permit holders three water quality parameters that may choose to better represent water must be monitored under the quality parameters other than TPH by Industrial Stormwater General collecting time-proportionate or flow- Permit. The information you obtain proportionate samples. These sam- from your lab may differ from this. In ples consist of a number of many cases, the preservatives listed in subsamples taken at intervals rather the table come pre-measured in the than a single grab sample. Time-pro- sampling bottles and there is no need portionate or flow-proportionate sam- to check pH. Ask your lab about this. pling can accurately define pollutant uHow to read the lab reports for the loading during various times of dis- sample results. Sampling requirements charge throughout a storm event and tend to use scientific words and units of determine whether or not higher pol- measure. Temperature is measured in lution is occurring during first flush degrees Celsius, “C”. Typical United of the storm. States thermometers measure A time-proportionate sample is one temperature in Fahrenheit, “F,” and made up of a number of small samples 4º C is about 39° F. For your purposes, (subsamples) of equal volume col- “Cooling to 4º C” means putting the lected at regular time intervals com- samples on crushed ice or packed with bined into a single large sample. A blue ice in an ice chest so they will be flow-proportionate sample is one kept just above freezing. Metric units made up of a number of subsamples are used to measure weight, volume where each subsample is collected in and distance. Liquid volumes use liters, such a way as to represent a given “L” and milliliters, “mL,” not “quarts” amount of stormwater discharge. and “cups”. Chemicals have their own Time-proportionate and flow-propor- scientific notation. Nitric acid for tionate samples provide the advantage of including a number of smaller sam- example is HNO3. Be sure to have the lab explain any words or expressions ples (subsamples) in the sample so that that you do not understand. the stormwater discharge is better

Advance Planning for Stormwater Sampling Page 4 represented than with a grab sample. tle (grab sample), taking grab samples Practice sampling Time-proportionate and flow propor- may be the easiest way to collect addi- before you do tionate samples can be collected either tional samples for the other parameters. by hand or with automated equip- Take samples by collecting stormwater the real thing. ment. Automated equipment can directly from the discharge into the provide unstaffed sample collection bottles supplied by the lab, filling each outside of normal business hours. bottle one after another. Additional information regarding Because TPH samples cannot be requirements for automated storm- transferred between containers, a sam- water sampling is available online at ple cannot be formed from separate http://www.ecy.wa.gov/programs/ grab samples combined together. If eap/qa/Agency/ECY_SOP_Automated more than one TPH sample is desired Sampling_v1_0.pdf. Collecting time- from a sampling site during a storm proportionate or flow-proportionate event, additional TPH grab samples samples by hand is somewhat difficult must be collected and analyzed and collecting them with automated separately. equipment involves additional ex- Because TPH samples must be penses, such as the installation of a collected directly and not through the flow meter for automated sampling. tubing of an automatic sampler, those using automatic samplers will still have to grab TPH samples by hand. Collecting total petroleum This is also true for facilities that must hydrocarbons (TPH) samples sample for fecal coliform. In addition to the requirement for all permit holders to monitor for a visible oil sheen, the general permit requires Determining which that facilities with the following indus- discharges to sample trial activities and Standard Industrial The first step in selecting sampling Classification (SIC) codes collect TPH points is to consider the areas drain- Total Petroleum samples: Primary Metals(33xx), Metals ing your facility. The site map in your (10xx), Automobile Salvage and SWPPP should show the drainage ar- Hydrocarbons (TPH) Scrap (5015and 5093), Metals eas. Areas of particular concern are samples must be Fabricating (34xx), Hazardous Waste those where raw materials or finished Treatment, Storage and Disposal Facil- product are exposed to rainfall collected directly ities and Dangerous Waste Recyclers and/or runoff, and areas where leak- into the bottle you subject to the provisions of Resource ing fluids such as petroleum products Conservation and Recovery Act and hydraulic fluids have the poten- send to the lab. (RCRA) Subtitle C. Because of the tial to enter stormwater runoff. particular way TPH samples must be The next step is to determine collected, this requirement may govern where the runoff from each drainage your overall approach to sampling. area is discharged from your facility. For some parameters other than If there are separate drainage areas TPH, it is possible to sample in difficult with separate discharge points, situations by filling a container and stormwater sampled at one discharge transferring it to the sample bottle to be sampling point may not represent the sent to the lab. TPH samples, however, facility’s stormwater quality overall. must be collected from the stormwater Section S4.B.2 on page 22 of the source directly. The sample cannot be Industrial Stormwater General Permit transferred from another container be- describes the requirements for select- cause oil and grease tends to stick to the ing sampling points: inside surfaces of containers. Since you must sample directly into the TPH bot-

Page 5 Advance Planning for Stormwater Sampling S4.B.2. Sample Location(s) ground. Outfalls that have these uThe Permittee shall designate similar characteristics are called “sub- Take time to sampling location(s) at the point(s) stantially identical outfalls,” and you get ready for where it discharges stormwater are required to monitor only one of associated with industrial activity the “substantially identical outfalls” sampling. offsite. rather than all of them. Refer to Con- uThe Permittee is not required to dition S3.B.5 on pages 20 and 21 of sample onsite discharges to ground the permit for how to determine if the (e.g., infiltration, etc.) or sanitary “substantially identical outfall” ex- sewer discharges under this permit, ception applies to some of your dis- unless specifically required by charge points, and be sure that your Ecology (Condition G12, page 45). SWPPP includes documentation of how sampling locations were chosen. uThe Permittee shall sample each If your facility has multiple dis- distinct point of discharge offsite charge points from areas with differ- except as otherwise exempt from ent industrial activities, BMPs, monitoring as a “substantially exposed materials, or impervious sur- identical outfall” per S3.B.5.b (pages faces, the discharge points would not 20 and 21). The Permittee is required be considered substantially identical to monitor only one of the outfalls, and therefore you would “substantially identical outfalls” if need to sample all of the outfalls. For two or more outfalls discharge example, if one portion of the site is substantially identical effluents used to store raw materials and dis- (based on similar industrial activities charges separately from another por- and site conditions). tion of the site where vehicle uThe exception to sampling each maintenance (e.g., fueling, lubrica- point of discharge in S4.B.2.c (page 22) tion, etc.) takes place, the stormwater does not apply to any point of discharge points would not be sub- discharge subject to numeric effluent stantially identical and both discharge limitations as described in Conditions points would need to be sampled. S5.C (page 27), S6.C (pages 30 and 31), Making a determination of and S6.D (pages 32 and 33). whether some of your discharge As a general matter, your stormwater points can be considered “substan- discharge samples will be taken tially identical outfalls” would require where your facility’s stormwater is careful consideration of Condition discharged offsite. If your facility dis- S3.B.5.b of the Industrial Stormwater charges stormwater collected over ar- General Permit. If you determine that eas that are used for similar activities some of your discharge points do not and have similar site conditions, and need to be sampled, the Sampling Plan there is reason to believe pollutant in your SWPPP needs to include docu- types will be similar in such areas, a mentation of why each discharge point single sampling point can be used to is not sampled per Condition S4.B.2.c, represent several discharge points. including: The Industrial Stormwater General a) The location of which discharge Permit allows you to sample at only points the Permittee does not sample one outfall when multiple outfalls at because the pollutant concentrations your facility have similar industrial are substantially identical to a dis- activities, best management practices charge point being sampled. (BMPs), exposed materials, and im- b) General industrial activities con- pervious surfaces that could affect ducted in the drainage area of each stormwater percolation into the discharge point.

Advance Planning for Stormwater Sampling Page 6 c) Best management practices con- point where the flow is from your facil- Manhole access can ducted in the drainage area of each ity only. Also check to see that there is be a good sample outfall. no base flow in the storm sewer during dry periods. Report in your SWPPP the point if it can be d) Exposed materials located in the drainage area of each discharge point presence of any base flow and measure accessed safely and that are likely to be significant contri- or estimate its flow rate. If it is not pos- butors of pollutants to stormwater sible to sample only flow from your fa- the stormwater is discharges. cility, document the reason for this and solely from your provide information concerning the e) Impervious surfaces in the drain- source of the flow you are sampling. facility. Do not age area that could affect the percola- If possible, the stormwater your fa- tion of stormwater runoff into the cility samples should not be a mixture climb into the ground (e.g., asphalt, crushed rock, of your facility’s stormwater with other manhole. Use a grass, etc.). water. Some examples of situations f) Reasons why the Permittee expects where a sample would be of a mixture sample bottle the discharge points to discharge sub- of water sources, and you should not attached to a pole stantially identical effluents. sample are listed below: to take the sample. Examples of mixed water sources Selecting sampling points situations in which you should not uPipes discharging your facility’s sample: stormwater offsite. uA ditch that carries additional uDitches carrying your facility’s stormwater from properties stormwater offsite. upstream. In this case, the stormwater uManhole access to storm sewers from your facility is mixed with other carrying your facility’s stormwater, so water and you should find a location you can lower a sample bottle or locations where only your facility’s attached to a pole into the manhole. stormwater can be sampled. u Base flow here In general, manhole access on your A stormwater sewer or pipe (culvert) property may be simpler and safer discharges to a creek or other receiving refers to any water than access off property and more water, the pipe being partially in the ditch that is readily verifiable as carrying only submerged where it discharges into the your facility’s stormwater. receiving water. In this case, this final not a direct result These three types of sampling points discharge point will not be able to be used as a sampling point because the of stormwater are usually not too difficult to access and the flow within them tends to be stormwater flow is mixed with the runoff. Ground fast enough, with enough turbulence, receiving water. u water seepage into to allow you to collect well mixed, A manhole that carries stormwater, representative samples. In some cases, not only from your facility but from the ditch, for portions of industrial stormwater run- other stormwater sources as well. If you are grabbing a sample from a manhole example, would add off leave a site as sheet flow. Specific approaches to sampling of pipes, but from the point where a storm sewer base flow. ditches, manholes, grated storm drains, from your facility ends at a municipal and sheet flow will be covered in the manhole, make sure that the flow in final section of this guide manual. that pipe is entirely from your facility, Make sure your sampling points that the pipe is not submerged or partly will provide for sampling only the submerged and that you are otherwise stormwater that comes from your facil- not prevented from collecting ity. If the stormwater in a pipe (storm stormwater from your facility only. If sewer) contains other discharges, move you are not sure that a storm sewer your sampling point upstream to a carries only flow from your facility, the

Page 7 Advance Planning for Stormwater Sampling municipality may have storm sewer Obtaining supplies plans to help you determine this. for sampling Contact the municipality beforehand to The supplies you will want to have discuss sampling from the manhole on hand before sampling include: and associated safety issues, u particularly for manholes in areas Sampling bottles from the lab, with vehicular traffic. including a few extra of each type. uWhen needed, a pole to hold It is important to sample flow from sample bottles and filament strapping only your facility if possible because tape. otherwise it cannot be determined u what the sample actually represents. If Powder-free disposable nitrile or you discharge stormwater to a storm- latex gloves . These are sold by water conveyance system that includes medical and laboratory suppliers. Do stormwater from other sources, you not use powdered gloves as the need to sample before your storm- powder may contain metals that water commingles with stormwater could contaminate metals samples from other sources. However, if storm- such as zinc. water runs onto your property in an uFoul-weather gear. uncontrolled fashion (for example, uOne or more coolers, depending on sheet flow) from adjacent property, the number of samples to be stored into areas of industrial activity on your and transported or shipped. site so that it becomes a part of the u stormwater discharge from your site, A bound notebook to serve as a this should be included in your sample field book for keeping records of stormwater discharge. If you are concerning sampling. Notebooks with concerned about this offsite source, waterproof pages are available for you may want to sample that storm- these field notes at office supply water where it enters your property. If stores. The information to be included the results show significant pollution, in the notes will be described in the you may want to provide Ecology “Keeping Records” section of this with a narrative description of the con- guide. You may find it helpful to tributing site and sample results to create a standardized form containing document the relative contribution of the information in this as well. the other property or upstream source. It is a good idea to observe the sampling point(s) you have chosen during actual stormwater runoff con- ditions to see how readily stormwater can be sampled there. Keep in mind that changing tides and flow condi- tions in receiving waters, including flood stages may occur during storm events. This may cause a pipe that is discharging your facility’s storm- water to become submerged or partly submerged, preventing you from sampling during some conditions.

Advance Planning for Stormwater Sampling Page 8 Planning Just Prior to Stormwater Sampling

ow that the bulk of the planning Choosing when to sample Sample during the Nfor sampling is complete, there are The permit requires that you sample a few things to keep in mind before the discharge from each designated first 12 hours of a deciding to actually begin sampling. location at least once per quarter: stormwater u1st Quarter = discharge Being prepared January, February, and March t is important to assemble every- u2nd Quarter = Ithing that will be needed for the April, May, and June sampling event ahead of time because u3rd Quarter = opportunities to sample during storm July, August, and September events often come with little advance u notice. Complete the identification 4th Quarter = tags and Lab Services Required form. October, November, and December Place the tags, lab form, field note- You will need to sample the “first fall book, permanent ink pen, meter, and storm event” each year. The permit pH paper in the cooler with the sam- defines the “first fall storm event” as ple bottles. Have resealable plastic the first time after October 1st that bags or other means on hand to keep precipitation occurs and results in a the pH paper dry. If you are using stormwater discharge from the a turbidity meter or pH meter, be facility. Please note that you are not prepared to protect them from the required to sample storm events that rain. Have foul-weather gear ready outside of normal business hours or and available. It will be necessary to in unsafe conditions. keep sufficient ice onsite or plan to Collect samples within the first 12 purchase ice that day. hours of stormwater discharge. If you

Page 9 Planning Just Prior to Stormwater Sampling are not able to collect a sample within A number of commercial websites, the first 12 hours, collect the sample such as http://www.weather.com/ and Take notes! as soon as possible. In the sampling http://www.accuweather.com/ also Writing down records, keep documentation explain- provide weather information and ing why you could not collect sam- forecasts. your observations ples within the first 12 hours. When evaluating a weather fore- at the time of If your facility is located in an area cast, consider indications of expected that is covered by a standing snow intensity, for example “90% chance” sampling is pack for days at a time during a year rather than “30% chance” and “rain” important. of normal precipitation, you may al- rather than “showers.” Over the tele- ternatively sample a snowmelt event phone, National Weather Service per- during the winter or spring quarter. sonnel can often provide estimates of anticipated rainfall amounts. In addi- tion to intensity, consider the pre- Check weather forecasts dicted duration of the storm. It will be Keeping up with the weather forecast very helpful to spend time observing and planning so that sampling can be rain events at your site with attention carried out on short notice are the to how rain intensity relates to storm- keys to successful sampling. water discharges from your site, be- Local forecasts, including televised fore you begin sampling. satellite and radar images can give an Once the decision has been made indication of the expected intensity of to attempt to sample a storm event, coming storms. The National Weather the personnel who will be sampling Service is an excellent source of infor- should be notified and they should mation on upcoming storms. It also prepare to sample. If it does rain, they includes local current radar and satel- should be at the sampling sites before lite images. Their website is: stormwater begins discharging so http://www.wrh.noaa.gov/index.php. they can document the time of dis- charge and be ready to sample.

Planning Just Prior to Stormwater Sampling Page 10 Conducting Sampling at Your Facility

fter you have selected a storm Simple principles of Have your sampling Aevent and it begins raining, the good grab sample collection: personnel conducting the sampling u kit ready to go. Wear disposable powder-free should prepare their equipment and gloves when sampling. go to the sampling site(s). They will u be collecting grab samples at the sam- Grab samples with the stormwater pling site(s), placing the samples in entering directly into bottles picnic coolers containing ice, and supplied by your lab rather than by keeping notes in a field book. Sam- transferring the samples from a pling for the first time may require container that may not be clean. Metal working out some difficulties, but af- contamination of ordinary containers ter performing these duties once, fu- is common and household detergents ture sampling will not be as difficult. often contain phosphorus, a tested parameter for some industries. Again, transferring the sample from another Checklist for sampling container is not an option for TPH Because stormwater sampling is not a samples under any circumstances. daily part of the workload of a facility, uWhen holding the sample bottle it is a good idea to keep a checklist of your lab has provided, keep your things to have prepared before sam- hands away from the opening in pling and to do during sampling. You order to prevent contaminating the can make the checklist by jotting down sample. the things you did for the first sampling uAlways hold the bottle with its event to remember for subsequent sam- opening facing upstream (into the pling events. If necessary, update this flow of water) so that the water enters checklist based on the experience you directly into the bottle and does not gain with each sampling event. first flow over the bottle or your hands. How to fill sample bottles uSample where the water has a This section and an illustrated appen- moderate flow and, if possible, some dix at the end of this guide describe turbulence, so that the stormwater how to collect a sample properly. Col- discharge will be well-mixed and the lecting a grab sample can be as simple sample will be representative. as holding a bottle under the storm- Sampling in still water should be water falling from a pipe and filling avoided. Include in your field book a the bottle properly. Still, the person note about the sample location and doing the sampling must use care in how briskly the water appears to be applying the principles outlined be- moving. low so that the sample will be repre- uSample from a central portion of sentative of the water being sampled. the stormwater flow, avoiding Additional information regarding touching the bottom of channels or grab sampling is available in Ecol- pipes so as not to stir up solid ogy’s standard operating procedures particles. (SOPs) for grab sampling online at u http://www.ecy.wa.gov/programs/eap/qa/ Do not rinse or overfill the bottles. Agency/ECY_SOP_GrabSampling_v1_0 The bottles supplied by your lab for .pdf. some parameters (ammonia and phosphorus) will include small

Page 11 Conducting Sampling at Your Facility amounts of liquid preservative sure to note in your field book how (generally a few drops). Fill the bottle to you collected your samples as this is about ½ inch of the top (not quite full) especially important for the TPH to ensure that no preservative is lost. sample. uAs soon as the sample is collected, cap the bottle and label it. It is Keeping records important that the bottles are labeled Take notes! Writing Section S9 on page 37 of the general correctly so that the lab will be able to permit specifies requirements for re- down your identify samples by sample site and porting and recordkeeping. In order ensure proper preservation for each observations at the to comply with the requirement that parameter. It is a good idea to place lab reports include sampling date and time of sampling is sample bottles in reclosable bags. Place sampling location, you will need to the samples in a picnic cooler partially supply this information to the lab important. filled with ice. Plan to maintain ice in when submitting samples. You can the picnic cooler until the samples do this by using the sample location arrive at the lab. Remember to make as the field station identification on certain that the samples will be your labels or sample tags. delivered to the lab soon enough for the You should purchase a notebook lab to meet holding times. for use in the field. Water resistant TPH sampling raises “rite in the rain” notebooks serve the additional concerns: purpose well. Section S4.B3.on page 22 of the u Oil and grease floats on water so permit requires that you record the TPH sampling requires special date, exact place, method, time of attention. TPH samples must be sampling or measurement, and the collected directly into the sample name of the individual who per- bottles supplied by the lab because oil formed the sampling or measurement and grease tends to stick to the sides (the section also specifies some re- of containers. Do not rinse the quirements for lab recordkeeping). sampling bottles beforehand or pour Record following information for the sample from another container. each stormwater sample taken and Do not fill the bottle completely and make it available for Ecology review: do not pour out some of the sample if the bottle is overfilled by mistake. If a) Sample date. you do overfill a bottle, use a new b) Sample time. bottle instead to collect your sample. c) A notation describing if the Because you only get one try at filling Permittee collected the sample within a TPH bottle, it is a good idea to have the first 12 hours of stormwater dis- plenty of extra bottles on hand. charge events. uTPH samples should be collected d) An explanation of why the Permittee as the stormwater falls from a pipe or could not collect a sample within the from a running, turbulent stream of first 12 hours of a stormwater discharge flow when possible so the source will event, if it was not possible. be well mixed. When the samples must be collected from a water e) Sample location (using SWPPP surface, the person holding the bottle identifying number). should plunge it below the surface in f) Method of sampling, and method a sweeping arc and then bring it of sample preservation, if applicable. upwards through the water surface g) Name of the individual who again, so the water surface is broken performed the sampling. twice by the mouth of the bottle. Be

Conducting Sampling at Your Facility Page 12 Although not required, it would also Entries in the field book should be Get the best sample be beneficial to record the following made with ink. If you make an error you can. information: in the field book, cross it out rather uWeather preceding the sampling event: than whiting out or erasing. Number - how many days/weeks/months the pages of the field book consecu- since last significant rainfall. tively. To ensure that the bound field - estimate of time it began raining. book is a complete record, do not rip - estimate of time that discharge pages from it. began at the sampling point. - amount (inches) and/or intensity When the sampled storm of precipitation. doesn’t meet the required - whether discharge includes ice criteria or snowmelt runoff. There may be times when, despite u How you collected the sample, your best efforts, you are unable to example, “from a ditch by hand” or collect grab samples during the first “from a manhole with the bottles on a 12 hours of a storm event. When this pole”. happens, the general permit states uThe number and types that the permittee must still collect (parameters) of samples collected. and submit a stormwater sampling result, and must include an explana- uField measurement results, such as tion with the sampling records (e.g., pH or visible oil sheen. record in field notebook). uAny unusual circumstances that may affect the sample results.

Page 13 Conducting Sampling at Your Facility Special Sampling Considerations

afety should be the primary con- Sampling as stormwater Don’t take risks. Ssideration in sampling. Samples discharges from a pipe should never be collected in a way into a receiving water Know how to that compromises the safety of the If stormwater is being discharged from sample safely. sampler. In cases where there is a your facility through a pipe into a physical hazard, such as a trip hazard ditch, creek, or other receiving water, or when sampling near deep water it can be readily sampled as it falls bodies, samplers should work in from the pipe before it reaches the re- pairs. Do not wade in water where ceiving water if the discharge pipe is the estimated depth in feet times the safely accessible and not submerged. velocity in feet per second is equal to Hold the bottles with the bottle open- or greater than 8, as swift currents can ing facing upstream into the flow and lead to drowning accidents. Be aware be sure not to overfill them. You may of the slip hazard common near the need to fasten the collection bottles to banks of water bodies and decide a pole to reach the pipe. Attaching a whether a bank is too steep to negoti- bottle to a pole is described in the sec- ate safely. Safety comes down to indi- tion below, Sampling from a Manhole. vidual judgment. Never put yourself in a position you consider to be un- safe. Collecting grab samples of Sampling from a manhole stormwater is basically a simple pro- When sampling from the manhole of cess but an important one since get- a municipal storm sewer, remember ting good results depends on proper to contact the municipality before- sampling. Samples can be collected hand. Be sure to discuss safety con- easily in some locations, but not all cerns when talking to the stormwater discharges are as readily municipality about sampling. Open a sampled as the flow in a ditch or from manhole with a hook or pick axe, ex- a pipe falling into a receiving water. ercising care not to drop the manhole Below are some situations you may cover on hands or feet. You should encounter and suggested approaches not, under any circumstances, enter for handling them. Because TPH sam- the manhole unless trained to safely ples must be collected directly into enter confined spaces, but you can the bottle supplied by the lab we will sample the flow in a manhole from consider only methods for collecting above ground by taping the sampling samples directly by hand or with a bottles, one at a time, to a pole and bottle attached to a pole. When sam- lowering the pole into the manhole. pling in these or other situations, Each bottle can be fastened to the keep in mind the steps outlined in the pole by holding the bottle against it section, How to Fill Sample Bottles.Ad- and wrapping tape tightly around the ditional information is available in bottom and the top of the bottle as you Ecology’s standard operating proce- hold the bottle firmly to the pole. Fila- dures (SOPs) for stormwater sam- ment strapping tape works well for pling available online at this purpose as it is waterproof and http://www.ecy.wa.gov/ strong. If the flow in the storm sewer is programs/eap/quality.html. shallow, the bottle may have to be po- sitioned horizontally with the bottle’s opening somewhat higher than its bot- tom. When sampling in a manhole, be

Special Sampling Considerations Page 14 careful not to scrape the bottle against Sampling sheet flow the sides of the pipe to avoid picking It is not always possible to sample up extras solids in your sample. stormwater runoff in locations such Collecting into bottles for TPH sam- as ditches or pipes where the flow is ples with a pole is done by plunging concentrated. Sometimes the the bottle on the pole below the water permittee has no choice but to select surface and back upwards. This must sample locations for which sheet flow be done as a single motion and only is sampled before it becomes concen- once. Because you only get one try at trated. Approaches to sampling sheet getting a good TPH grab sample, it may flow are described below and illus- take some practice and extra bottles to trated in the figures that follow. collect the amount of sample you need In some cases, a stormwater dis- without overfilling the bottle. charge from a facility is not concen- Collecting samples, other than trated at any point and leaves the TPH, into bottles with preservative can property in the form of sheet flow as be done by quickly plunging the pole it runs off a work area or driveway or into the flow repeating if necessary un- grassy area. In this case the flow may til the bottle is most but not all of the be too shallow for the collection bottle way full. If you overfill the bottle, re- to be filled with sample. It is often move it, tape a clean bottle to the pole, possible to find a way to collect the and try again. Be sure, when collecting stormwater runoff in these situations. samples with a pole, to follow clean One way to concentrate sheet flow principles by keeping the pole down- is to install a barrier device or trough, stream of the bottle while sampling. When sampling from a man- gutter, or ditch to intercept and con- hole, use a pole to safely centrate stormwater flow. As with sample from above ground. Sampling from a drainage other sample sites, the flow should be Avoid touching the sides of ditch or swale moving and somewhat turbulent so the manhole or pipes with the samples will be well-mixed. Be If a drainage ditch carries stormwater the bottle to prevent con- sure that any excavation you do does tamination. Place the open- flow from your facility offsite, and if not expose the stormwater to be sam- ing of the bottle upstream so it carries no flow other than the flow pled to newly worked soil surfaces that the flow enters the bot- from your facility, you can sample the that the runoff may erode, increasing tle directly. water in the ditch simply by placing the solids in your samples. You may the bottle where the flow is free, with want to consider lining the trough, the bottle opening facing upstream. If gutter, or ditch with plastic. Be sure you cannot reach a freely flowing not to introduce materials such as portion of the ditch by hand, you may metals that include zinc that may con- need to attach the bottles, one at a taminate the samples. Sheet flow on time, to a pole for sampling. Follow paved areas can be concentrated and the procedure outlined in the section, collected by constructing small How to Fill Sample Bottles. bumps, similar to speed bumps. If the flow is carried in a small Another way to collect samples ditch or swale, you can install a bar- from sheet flow is to use a special rier device in the channel or deepen a peristaltic hand pump to pump sam- small area so you can gain enough ples from shallow surface flows. This depth of flow to sample directly into method is of limited use for collecting the bottles. Make sure to allow for the samples required by the general sufficient time after disturbing the permit as it cannot be used to collect bottom so that the solids resulting TPH samples. from muddying the water will not be- come part of your sample.

Page 15 Special Sampling Considerations Roger Bannerman of the Wiscon- sin Department of Natural Resources has developed simple devices to grab samples of sheet flow from paved ar- eas, rooftops, and lawns. Though the devices are intended to be used for simple, automatic sampling, pouring a container of collected sample into other sample bottles, the ways in Runoff entering a catch basin can sometimes which they intercept and concentrate be collected directly into bottles by remov- flows can be adopted for direct grab ing the grate and allowing the runoff to fall sampling. into the bottles. The following figures illustrate the methods of sampling sheet flow dis- cussed above:

Deepening an existing ditch can allow sam- ples to be collected directly into bottles in Overland flow on paved areas can be sam- some cases. Be careful not to stir up solids pled by constructing asphalt or from the sides or bottom of the ditch. bumps to collect and concentrate the flow. A box positioned below ground surface in the paved area or the edge of an unpaved area can provide a place to collect samples di- rectly into bottles. Please note that dirt and other debris can often build up along the bumps and in the “v” so, you may want to clean the area prior to taking the sample.

Sampling from a stormwater detention pond or other BMP When stormwater from a facility dis- Overland flow from vegetated areas can be charges after flowing through a de- sampled by constructing a shallow ditch to tention pond or other treatment intercept the runoff and a deepened area to place bottles to catch the runoff. system, sample as the stormwater flows out at the discharge point. Ponds may hold stormwater for a time before discharge begins. Sample within the first 12 hours from when the pond begins to discharge.

Special Sampling Considerations Page 16 Ecology Wants to Hear from You

f you have suggestions on how uAdams, Asotin, Columbia, Ferry, IEcology can improve this guidance Franklin, Garfield, Grant, Lincoln, document, have developed innova- Pend Oreille, Skagit, Snohomish, tive sampling techniques, or just want Spokane, Stevens, Walla Walla, to comment on stormwater sampling, Whatcom, or Whitman County please contact the appropriate permit Shawn Hopkins administrator for your county: 360-407-6437 uCity of Seattle, Kitsap, Pierce, or [email protected] Thurston County uBenton, Chelan, Clallam, Clark, Josh Klimek Cowlitz, Douglas, Grays Harbor, 360-407-7451 Jefferson, Kittitas, Klickitat, Lewis, [email protected] Mason, Okanogan, Pacific, Skamania, uIsland, King, or San Juan County Wahkiakum, or Yakima County Clay Keown Joyce Smith 360-407-6048 360-407-6858 [email protected] [email protected]

Page 17 Ecology Wants to Hear from You Appendix - Proper and Improper Methods of Sampling

DO NOT allow bottle lids to touch ground. Keep lids clean to prevent contamination.

DO always wear gloves when taking samples.

DO NOT touch openings of bottles. Keep bot- tles clean to prevent contamination.

DO attach a bottle to a pole for sampling in manholes or when a hand sample would be in stagnant water. A boathook is used in this example and the bottle is attached to it with filament strapping tape.

DO NOT sample in stagnant areas with little flow. DO NOT stir up bottom sediments or allow foreign materials to enter the sample bottle. (DO be careful to grab a clean sample in cases where stormwater runoff is shal- low.) If the runoff is so shallow that it is not possible to sample without the sample being contaminated in the process, then find an al- ternative way to sample.

If the water is too shallow to sample with the bottle upright on the pole, try taping it on sideways, but tilted up slightly.

Appendix - Proper and Improper Methods of Sampling Page 18 DO NOT sample with the bottle opening fac- ing downstream, when using a pole or sam- DO NOT allow water to overfill the bottle, pling by hand. Water flowing past your particularly not for sample bottles with pre- container, pole, or hand and into the con- servative. TPH samples should be collected tainer can be contaminated by such contact. from water falling into the bottle when pos- sible, or otherwise in a single swoop.

DO sample with the opening of the bottle facing upstream, into the flow so the water DO collect samples without overfilling the will enter directly into the bottle. This is bottles. true when sampling either by hand or with a pole. DO sample water that is rapidly flow- ing rather than stagnant.

Page 19 Appendix - Proper and Improper Methods of Sampling References

Bannerman, R.T.; Owens, D.W.; Thrush, Cindy and De Leon, Dana B., Dodds, R.B.; Hornewer, N.J., 1993. 1993. Automatic Stormwater Sampling Sources of Pollutants in Wisconsin Made Easy, Water Environment Stormwater, Wat. Sci. Tech. Vol. 28. Federation. No. 3-5, pp 241-259. United States Environmental Colorado Department of Public Protection Agency, 1992. NPDES Health and Environment; Water Storm Water Sampling Guidance. Quality Control Division; Colorado EPA 833-B-92-001. Discharge Permit System, 1996. CDPS Stormwater Sampling Waschbusch, R.J.; Selbig, W.R.; Guidance Document. Bannerman, R.T., 2000. Sources of Phosphorus in Stormwater and Street Dodson, Roy D., 1995. Storm Water Dirt from Two Urban Residential Basins Pollution Control: Municipal, Industrial, in Madison, Wisconsin, 1994-95. and Construction NPDES Compliance, National Conference on Tools for 1999, 1995. Second Edition. Urban Water Resource Management McGraw-Hill. and Protection Proceedings, February 7-10, 2000, Chicago, IL. Ecology, 2005. The Industrial Storm- water General Permit: A National Pollut- Wisconsin Department of Natural ant Discharge Elimination System and Resources Bureau of Water State Waste Discharge General Permit Management Municipal Wastewater for Stormwater Discharges Associated Section – Storm Water Unit, 1994. with Industrial Activities. State of Wisconsin’s Guidance for Industrial Washington Department of Ecology, Storm Water Monitoring. January 14, 2005. Torno, Harry C., 1995. Stormwater Ecology, 2000, 1999. Field Operations NPDES Related Monitoring Needs, and Safety Manual: Environmental American Society of Civil Engineers. Assessment Program, Washington State Department of Ecology, Environmen- tal Assessment Program, Updated August 2000.

New Jersey Department of Environ- mental Protection Division of Water Quality, 1998. General Sampling and Reporting Guidance for PAS and ADI Form.