7.4 Sample Preservation, Data Recording, Shipping, and Chain of Custody

Free CESSWI Certified Erosion, Sediment and Stormwater Inspector Study Guide 2026 Exam

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1 Chapter 1: CESSWI Program Overview, Scope of Practice & Professional Ethics

1.1 CESSWI Scope of Practice, Eligibility, and Exam Structure 1.2 Certification Renewal, PDH Requirements, and Audit Policies 1.3 EnviroCert Code of Ethics and Professional Conduct

2 Chapter 2: Federal, State, and Local Stormwater Regulations

2.1 Federal Water-Pollution History and Stormwater Phases 2.2 CWA Sections, Water Quality, and Related Federal Programs 2.3 EPA Construction Permit Coverage and Operational Clocks 2.4 Industrial MSGP and Municipal MS4 Programs 2.5 Regulatory Compliance, Enforcement Mechanisms, and Penalties

3 Chapter 3: Soil Mechanics, Erosion Processes, and Climatic Factors

3.1 Soil Formation, Horizons, and Geomorphology 3.2 Soil Texture, Mechanics, and Revegetation 3.3 Splash, Sheet, Rill, Gully, Channel Erosion, and Slope Movement 3.4 Wind Erosion, Sediment Transport, Climatic Erosivity, and Resource Impacts

4 Chapter 4: Hydrology, Runoff Characteristics, and Drainage Principles

4.1 The Hydrologic Cycle, Watershed Drainage Planning, and Precipitation 4.2 Hydrologic Soil Groups, Disturbed Profiles, and Time Parameters 4.3 Hydrograph Characteristics, Curve Numbers, and Runoff Estimation Equations

5 Chapter 5: Inspection Fundamentals, Duties, and Field Procedures

5.1 Inspector Roles, Scope of Authority, and Core Professional Skills 5.2 Pre-Inspection Document Review and Inspector Support Equipment 5.3 Systematic Field Inspection Sequence, Post-Inspection Meetings, and Follow-Through

6 Chapter 6: Inspection Elements for Active Construction Sites

6.1 Pre-Construction Meetings, Entrance Posting, and On-Site Document Inspections 6.2 Inspecting Active Construction Controls and Diagnosing BMP Failure Modes 6.3 Final Stabilization Verification, Final Inspections, and Notice of Termination

7 Chapter 7: Stormwater Monitoring, Field Sampling, and Chain of Custody

7.1 Permit Monitoring Triggers and Water-Quality Indicators 7.2 Sampling Preparation and Analytical Parameters 7.3 Sampling Locations, Collection Methods, and Field Meter Calibration 7.4 Sample Preservation, Data Recording, Shipping, and Chain of Custody

8 Chapter 8: Inspection Documentation, Reporting, and Map Management

8.1 Inspection Notes and Evidence Procedures 8.2 Objective Findings and Photographic Evidence 8.3 Proper Reporting Techniques and Corrective Action Log Management 8.4 Site Drawing (Map) Management, Compliance Resolution, and Enforcement Records

9 Chapter 9: Professional Communication and Site Safety for Inspectors

9.1 Communication Protocols in Pre-Construction, Post-Inspection, and O&M Meetings 9.2 Dealing with Difficult People, Problematic Sites, and Unpleasant Findings 9.3 Site Hazard Recognition: Physical, Biological, Trenching, and Confined Spaces 9.4 Hazardous Substances, Safety Data Sheets (SDS), Spill Response, and PPE

10 Chapter 10: Stormwater Plan Reading, Map Interpretation, and Site Calculations

10.1 Stormwater Plan Types, Credentials, and Authority 10.2 SWPPP Components and Permit Notifications 10.3 Civil Plan Sets, Legends, Phased Sequencing, and Living Site Maps 10.4 Topography, Contour Lines, Slope Calculations, and Plan Amendments

11 Chapter 11: BMP Framework, Site Planning, and Erosion Control Practices

11.1 Six Functional BMP Categories, Preservation of Vegetation, Phasing, and Tree Protection 11.2 Seeding and Sod Establishment 11.3 Hydroseeding and Hydromulching Inspection 11.4 Mulch and Rolled Erosion-Control Products 11.5 Tackifiers, Soil Binders, Roughening, and Temporary Cover

12 Chapter 12: Perimeter, Linear, and In-Water Sediment Control Practices

12.1 Perimeter & Sheet-Flow Sediment Barriers: Silt Fence, Fiber Rolls, Straw Bales, and Filter Dikes 12.2 Access & Roadside Sediment/Runoff Controls: Stabilized Entrances, Cut-Back Curbs, and Ditch Checks 12.3 In-Water & Dewatering Controls: Temporary Stream Crossings, Turbidity Curtains, and Sediment Bags

13 Chapter 13: Sediment Basins, Traps, and Runoff Conveyance Controls

13.1 Sediment Basins and Traps 13.2 Porous Baffles and Surface Skimmers 13.3 Runoff Conveyances: Diversions, Swales, Pipe Slope Drains, and Rock Check Dams 13.4 Riprap and Gabion Inspection 13.5 Retaining Walls, Outlet Protection, and Wet Ponds

14 Chapter 14: Storm Drain Inlet Protection and Good Housekeeping BMPs

14.1 Storm Drain Inlet Protection: At-Grade, Curb, Block & Gravel, Excavated, Fabric Drop, Gravel Bag, Stone Collar, and Pre-Manufactured 14.2 Good Housekeeping Part 1: Concrete Washout, Equipment Maintenance, Materials Management, and Secondary Containment 14.3 Good Housekeeping Part 2: Stockpiles, Dust Control, Wind Fence, Street Cleaning, Sanitary Waste, and Trash

15 Chapter 15: Post-Construction Stormwater Management BMPs

15.1 Vegetative & Structural Dispersion BMPs: Final Ground Cover, Headwalls, Level Spreaders, Filter Strips, and Riparian Buffers 15.2 Permeable Surfaces and Construction Protection 15.3 Infiltration, Bioretention, and Media Filters 15.4 Detention, Retention & Proprietary BMPs: Dry/Wet Basins, Wetlands, Inline Storage, Catch Basin Inserts, Vaults, and Manufactured Devices

7.4 Sample Preservation, Data Recording, Shipping, and Chain of Custody

Key Takeaways Explain This Topic AI

Thermal preservation requires chilling laboratory stormwater samples immediately on bagged wet ice to 4 degrees Celsius (at or below 6 degrees Celsius without freezing) alongside a temperature blank, while chemical preservation acidifies metals with nitric acid (HNO3) to pH < 2 and nutrients/oil-and-grease with sulfuric acid (H2SO4) to pH < 2.

Under 40 CFR Part 136, maximum holding times from collection to analysis are within 15 minutes (immediate field analysis) for pH, temperature, and dissolved oxygen; 48 hours for laboratory turbidity; 7 days for Total Suspended Solids (TSS); 28 days for nutrient and oil-and-grease samples; and six calendar months for most total metals; mercury depends on the method.

Every sample bottle must be labeled in indelible waterproof ink with Project ID, Station ID, Sample ID, Date, 24-hour Collection Time, Collector's Initials, Requested Analysis, and Preservative, matched to contemporaneous entries in a bound waterproof field logbook.

A Chain of Custody (COC) is the unbroken chronological legal record of sample possession; a sample is legally in custody only when in physical possession, in direct line of sight, locked in a controlled secure area, or inside a cooler sealed with signed and dated tamper-evident Custody Seals.

Last updated: October 2026

Sample Preservation, Holding Times, and Quality Control Blanks

Important

Why Preservation and Holding Times Matter: The moment stormwater is isolated inside a sample bottle, biological respiration, chemical oxidation, metal adsorption onto container walls, and gas volatilization begin altering its chemistry. Under 40 CFR Part 136 , a sample arriving outside its method-specific preservation or holding requirements has a quality defect that must be documented and evaluated with the laboratory and permitting authority.

In CESSWI General Principles Review Manual Section 9.7 (SAOP 8 Test Objective 6), sample integrity between field collection and laboratory analysis relies on three pillars: thermal/chemical preservation , holding time compliance , and field QA/QC blanks and duplicates .

1. Thermal, Chemical, and Physical Preservation Methods

Thermal Preservation ( 4 ∘ C 4^\circ\text{C} 4 ∘ C on Wet Ice): Immediately after collection and capping, laboratory samples requiring cooling (such as TSS \text{TSS} TSS , laboratory turbidity, nutrients, oil and grease, and bacteria) must be placed inside an insulated cooler packed with double-bagged wet ice to chill and maintain the samples at 4 ∘ C 4^\circ\text{C} 4 ∘ C (accepted regulatory receipt range > 0 ∘ C > 0^\circ\text{C} > 0 ∘ C to ≤ 6.0 ∘ C \le 6.0^\circ\text{C} ≤ 6. 0 ∘ C without freezing) in the dark.

Why Wet Ice Instead of Dry Ice or Loose Blue Ice Packs: Wet ice reliably maintains a 0 ∘ C 0^\circ\text{C} 0 ∘ C to 4 ∘ C 4^\circ\text{C} 4 ∘ C melt equilibrium. Dry ice (solid CO 2 \text{CO}_2 CO 2 at − 78.5 ∘ C -78.5^\circ\text{C} − 78. 5 ∘ C ) is prohibited for water samples because it freezes and shatters glass bottles and can infiltrate caps to carbonate and acidify water samples. Unassisted blue gel packs warm rapidly in hot vehicles and frequently fail the ≤ 6.0 ∘ C \le 6.0^\circ\text{C} ≤ 6. 0 ∘ C lab receipt gate.

Temperature Blank: Every cooler must contain a dedicated temperature blank —a small unpreserved bottle of water packed among the sample bottles. When the cooler arrives at the laboratory, the sample custodian measures the temperature blank to verify that samples remained at ≤ 6.0 ∘ C \le 6.0^\circ\text{C} ≤ 6. 0 ∘ C during transit without opening and contaminating the actual analytical samples.

Chemical Preservation:

Nitric Acid ( HNO 3 \text{HNO}_3 HNO 3 ) to pH < 2 \text{pH} < 2 pH < 2 : Added to Total Recoverable Metals samples in acid-cleaned HDPE bottles. Acidification keeps metal ions in solution so they do not precipitate as metal hydroxides or adsorb onto the plastic bottle walls. ( Note: When analyzing Dissolved Metals , the sample must be filtered in the field through a 0.45 μ m 0.45\text{ }\mu\text{m} 0.45 μ m pore-size membrane filter before adding HNO 3 \text{HNO}_3 HNO 3 ; adding acid before filtering dissolves suspended clay-bound metals and ruins the dissolved measurement!)

Sulfuric Acid ( H 2 SO 4 \text{H}_2\text{SO}_4 H 2 SO 4 ) to pH < 2 \text{pH} < 2 pH < 2 (plus cooling to 4 ∘ C 4^\circ\text{C} 4 ∘ C ): Added to Nutrient samples (Total Phosphorus, Ammonia, Total Kjeldahl Nitrogen, combined Nitrate+Nitrite), Chemical Oxygen Demand ( COD \text{COD} COD ) , and Oil and Grease (which may use H 2 SO 4 \text{H}_2\text{SO}_4 H 2 SO 4 or HCl \text{HCl} HCl ) to halt bacterial metabolism.

Sodium Thiosulfate ( Na 2 S 2 O 3 \text{Na}_2\text{S}_2\text{O}_3 Na 2 S 2 O 3 ): Pre-dosed in sterile bacteria bottles to neutralize any trace residual chlorine that would otherwise continue killing indicator bacteria inside the bottle during transit.

Physical Zero-Headspace Preservation: Samples for Volatile Organic Compounds ( VOCs \text{VOCs} VOCs ) are collected in 40 mL 40\text{ mL} 40 mL glass VOA vials with PTFE-lined septa caps (preserved with HCl \text{HCl} HCl and cooled to 4 ∘ C 4^\circ\text{C} 4 ∘ C ). The vial is filled to a convex dome meniscus and capped so that zero headspace (zero air bubbles) remains when inverted; even a pea-sized air bubble allows volatile organics to partition out of the water phase.

2. High-Yield Maximum Holding Times (40 CFR Part 136)

The holding time clock starts at the collection time ; for an automated composite, 40 CFR 136 Table II footnote 3 generally starts the holding time at the end of collection, while manual compositing generally starts at the first grab. Immediate field parameters and particular methods have separate requirements:

Immediate Field Analysis (Within 15 Minutes): pH , Temperature , Dissolved Oxygen ( DO \text{DO} DO ) , and Total Residual Chlorine .

6 to 8 Hours (Max 24 Hours for Specific Non-Potable Methods): Microbiological Indicator Bacteria ( E. coli , Fecal Coliform, Enterococci) cooled at < 10 ∘ C < 10^\circ\text{C} < 1 0 ∘ C ( 4 ∘ C 4^\circ\text{C} 4 ∘ C ).

48 Hours: Laboratory Turbidity (stored in the dark at no more than 6°C), Settleable Solids (cooling is not specified in Table II), Biochemical Oxygen Demand ( BOD 5 \text{BOD}_5 BOD 5 ) ( 4 ∘ C 4^\circ\text{C} 4 ∘ C ), and Unpreserved Nitrate ( NO 3 − \text{NO}_3^- NO 3 − ) ( 4 ∘ C 4^\circ\text{C} 4 ∘ C ).

7 Days: Total Suspended Solids ( TSS \text{TSS} TSS ) and Total Dissolved Solids ( TDS \text{TDS} TDS ) cooled at 4 ∘ C 4^\circ\text{C} 4 ∘ C (no chemical preservative).

28 Days: Oil and Grease ( H 2 SO 4 \text{H}_2\text{SO}_4 H 2 SO 4 or HCl \text{HCl} HCl to pH < 2 \text{pH} < 2 pH < 2 , 4 ∘ C 4^\circ\text{C} 4 ∘ C ), Total Phosphorus / Ammonia / Preserved Nitrate+Nitrite ( H 2 SO 4 \text{H}_2\text{SO}_4 H 2 SO 4 to pH < 2 \text{pH} < 2 pH < 2 , 4 ∘ C 4^\circ\text{C} 4 ∘ C ), and Mercury by routine CVAA (nitric acid to pH < 2); CVAFS has different preservation and a 90-day holding time.

6 Months: Total and Dissolved Metals (all metals except Mercury, preserved with HNO 3 \text{HNO}_3 HNO 3 to pH < 2 \text{pH} < 2 pH < 2 ).

3. Field Quality Assurance / Quality Control (QA/QC) Samples

To prove to regulators that field data are both precise and free from artificial contamination, SAPs incorporate three standard field QA/QC sample types:

QA/QC Sample Type How It Is Prepared in the Field What Error or Bias It Detects

Field Duplicate (or Split Sample) Two separate sample bottles filled simultaneously (or back-to-back) at the exact same station and time (or split from one homogenizer churn) Measures total sampling and analytical precision (reproducibility) via Relative Percent Difference ( RPD \text{RPD} RPD )

Equipment Rinsate Blank (Field Blank) Analyte-free deionized (DI) water poured through decontaminated sampling gear (e.g., dipper cup or autosampler tubing) in the field, bottled, and preserved Detects cross-contamination from inadequately cleaned sampling equipment, contaminated acid preservatives, or dusty air

Trip Blank (VOCs Only) Sealed 40 mL 40\text{ mL} 40 mL VOA vials filled with analyte-free water at the lab, carried unopened to the site inside the cooler, and returned to the lab with the samples Detects volatile organic cross-contamination occurring during bottle transit, cooler storage, or shipping

Recording Field Sampling Data and Bottle Labeling
Indelible Bottle Labeling Requirements the approved practice detail

Every sample container must carry a waterproof adhesive label completed in indelible, waterproof ink (permanent waterproof marker or ballpoint pen— never pencil or water-soluble felt pen ). Best practice is to write the label and affix it to the dry bottle before immersing the bottle, then fill in the exact minute of collection immediately upon capping. Every bottle label must display seven mandatory data elements:

Project / Site Name and Permit Number
Sampling Location / Station ID (e.g., Outfall-001 , Creek-Upstream )
Unique Sample Identification Number (matching the Chain of Custody line item)

Date and Exact Time of Collection (written in 24-hour military time , such as 15:20 , to eliminate AM/PM confusion and establish the legal holding-time start)

Sample Collector's Initials or Full Name
Requested Analytical Parameter(s) and Sample Type ( Grab vs. Composite )
Preservative Used (e.g., HNO3 to pH < 2 , H2SO4 to pH < 2 , Cool 4C , or None )
Contemporaneous Entries in a Bound Field Logbook

Bottle labels alone are never sufficient. At the time of collection, the CESSWI must record complete sampling metadata in a bound, weatherproof (Rite in the Rain) field logbook with pre-numbered pages using indelible ink:

Correction Protocol: If a writing error occurs in a field logbook or on a Chain of Custody form, never erase, scribble out, tear out a page, or use correction fluid (white-out) . Draw a single horizontal line through the incorrect entry so it remains legible, write the correct value next to it, and sign your initials and the date beside the correction.

Required Field Notes: Weather conditions (air temperature, wind, precipitation type), current and 24-hour on-site rain gauge depth , storm start time, estimated or gauged outfall discharge rate ( Q Q Q ) / flow depth , visual and olfactory water characteristics (color, clarity, odor, foam, floatables, oil sheen), all field meter readings ( NTU \text{NTU} NTU , pH \text{pH} pH , temperature, DO \text{DO} DO ) with confirmation of daily calibration/drift checks, and time-stamped photographs of the outfall and labeled bottles.

Chain of Custody (COC) Procedures and Sample Shipping
Definition and Legal Purpose of Chain of Custody the approved practice detail

The Chain of Custody (COC) is the unbroken, chronological legal document that tracks the possession, handling, and transfer of environmental samples from the exact moment of field collection through transport, laboratory receipt, internal analysis, and final disposal. Because stormwater sample results can trigger six-figure Clean Water Act civil penalties or criminal prosecution, opposing attorneys routinely scrutinize the COC first: any unexplained gap in custody, missing signature, mismatched bottle ID, or broken custody seal can render the laboratory results legally inadmissible in court.

The Four Legal Conditions of "In Custody"

Under EPA and environmental forensic standards, a stormwater sample is normally documented as under a person's custody when at least one of the following four conditions is satisfied:

Actual Physical Possession: The sample is physically held by or carried on the person of the authorized custodian.

Direct Line of Sight: The sample is in the custodian's unobstructed, continuous view after having been in their physical possession.

Locked in a Controlled Secure Area: The sample was placed by the custodian inside a locked vehicle, locked field cabinet, or locked refrigerator to which only authorized personnel control access.

Sealed in a Tamper-Evident Container: The sample is inside a designated container (such as a shipping cooler) sealed with signed and dated tamper-evident Custody Seals across the lid seams so that the container cannot be opened without visibly tearing or breaking the seal.

Executing Custody Transfers and Commercial Courier Shipping

Person-to-Person Custody Transfer: Whenever samples are handed from one person to another (for example, from the field CESSWI to a courier or directly to the laboratory sample reception desk), both individuals must sign the Chain of Custody form at the moment of transfer :

The person giving up the samples signs the "Relinquished by" block, prints their name and company, and records the exact date and 24-hour time .

The person taking possession inspects the bottles against the COC lines, signs the "Received by" block, prints their name and organization, and records the exact date and 24-hour time .

Shipping Samples via Commercial Courier (FedEx / UPS Protocol): When samples are shipped to an off-site laboratory via a commercial parcel carrier (such as FedEx or UPS), the delivery driver will not open the cooler or sign the internal COC form. To preserve an unbroken legal Chain of Custody during commercial shipment, the CESSWI must execute five steps:

Package the Cooler: Wrap glass bottles in bubble wrap, verify all caps are tight, place bottles upright inside a plastic-lined cooler alongside the temperature blank , pack double-bagged wet ice around the bottles (never loose ice that melts into water and soaks off labels), and add absorbent padding.

Sign and Bag the COC Inside the Lid: Complete all sample lines on the COC form, sign the "Relinquished by" box with the date and time, retain the sampler's carbonless copy, seal the original signed COC form inside a waterproof zip-top plastic bag , and tape the bagged COC form to the underside of the cooler lid .

Apply Tamper-Evident Custody Seals: Close and tape the cooler drain plug and lid shut, then affix at least two adhesive paper Custody Seals —signed and dated in indelible ink by the inspector—across opposite lid seams/hinges so the cooler lid cannot be lifted without ripping the seals (cover the seals with clear packing tape to protect the ink from rain while ensuring the paper seal still tears if peeled).

Record the Courier Airbill / Tracking Number: Write the commercial courier's airbill / tracking number on the COC copy and in the field logbook to document transit custody.

Laboratory Receipt Verification: Upon arrival at the lab, the laboratory sample custodian inspects the exterior Custody Seals to confirm they are intact, opens the cooler, measures the temperature blank ( ≤ 6.0 ∘ C \le 6.0^\circ\text{C} ≤ 6. 0 ∘ C ), verifies headspace and preservative pH \text{pH} pH , and signs "Received by Laboratory" with the exact date and time.

End-to-End Stormwater Sampling, Calibration, Preservation, and Chain of Custody Workflow

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For the detailed method and approval qualifications, review the related CESSWI explanation .