Scenario Launch and Integrated Site Assessment

What Is a Site Assessment and Why Does It Matter?

Before you can operate, troubleshoot, or design improvements to any water or wastewater facility, you need a clear, documented picture of exactly what is on the site, what rules apply, and where people can get hurt. That structured picture is the site assessment. In the capstone project, your site assessment becomes the foundation for everything that follows — your operations plan, your chemical feed calculations, your regulatory compliance strategy, and your final defense presentation.

A weak assessment leads to missed hazards, overlooked permits, and process errors that can cost a utility thousands of dollars in fines or, worse, put workers and the public at risk. Experienced operators and engineers complete a formal scope-of-work document at the start of every significant project. This lesson teaches you how to do the same.

Reading the Scenario Packet

Your instructor will hand you a scenario packet built around an actual small-system or municipal facility. Read it completely before writing anything. Look for four categories of information:

1. Facility type and purpose — Is this a drinking water system, a wastewater treatment plant, or a combined utility? What population or flow does it serve?

2. Flow and loading data — Average daily flow, peak hourly flow, and influent/effluent quality parameters (BOD, TSS, turbidity, coliform counts, pH, and similar values depending on system type).

3. Location context — Is the facility in a flood-prone area, near a sensitive receiving water, or in a primacy state with its own regulations layered on top of federal rules?

4. Existing infrastructure clues — Tank sizes, pump ratings, chemical storage descriptions, and any mention of permits or violations.

Highlight or annotate as you read. Every detail in the packet is there for a reason.

Completing the Site Assessment Worksheet

The worksheet organizes your observations into four columns: unit process, applicable permit or permit condition, chemical hazards present, and confined space or lockout/tagout (LOTO) points.

Unit processes are the individual treatment steps — examples include coagulation/flocculation, sedimentation, filtration, disinfection, aeration, activated sludge basins, clarifiers, anaerobic digesters, and chlorine contact chambers. List every step from raw water or raw wastewater intake to final discharge or distribution.

Regulatory triggers vary by system type. Drinking water systems are governed primarily by the Safe Drinking Water Act (SDWA) and the rules EPA publishes under it, such as the Surface Water Treatment Rule and the Total Coliform Rule. Wastewater discharges to surface waters require a National Pollutant Discharge Elimination System (NPDES) permit under the Clean Water Act. Your scenario packet will indicate which rules apply; your job is to list the specific permit conditions (effluent limits, monitoring frequencies, reporting deadlines) that the facility must meet.

Chemical hazards must be identified for every substance on site — chlorine gas, sodium hypochlorite, anhydrous ammonia, ferric sulfate, polymer, and others. For each chemical, note the primary hazard (corrosive, oxidizer, toxic gas, etc.), the required personal protective equipment (PPE), and the location of the Safety Data Sheet (SDS). Never assume a chemical is safe because it is used in water treatment. Chlorine gas, for example, is immediately dangerous to life and health (IDLH) at concentrations far lower than its noticeable odor threshold.

Confined spaces and LOTO points must be listed explicitly. OSHA's permit-required confined space standard (29 CFR 1910.146) applies to any space large enough to enter bodily, not designed for continuous occupancy, and containing a recognized hazard — wet wells, digesters, chemical storage vaults, and underground valve chambers are common examples. Each one requires a permit, atmospheric testing, and an attendant before entry. LOTO (lockout/tagout) procedures under OSHA 29 CFR 1910.147 protect workers from unexpected energization of equipment during maintenance. Every pump, blower, valve actuator, and electrical panel is a potential LOTO point. List them by location and equipment tag if the scenario provides that information.

Sketching the Preliminary Process Flow Diagram

A process flow diagram (PFD) is a schematic map of how water or wastewater moves through the facility. It is not an engineering drawing; it does not need to be to scale. It does need to be logically sequenced and legible.

Use a straightedge and pencil. Draw each unit process as a labeled box or standard symbol. Use arrows to show flow direction. Annotate each unit with the key water quality parameter it addresses — for example, label a sedimentation basin with "removes suspended solids" and label a chlorine contact chamber with "inactivates pathogens / CT compliance." Use colored pencils to distinguish water flow, chemical feed points, and waste or residuals streams. A well-drawn PFD lets anyone — including a state inspector or your capstone evaluator — understand the treatment train at a glance.

Writing the Scope-of-Work Document

The scope of work summarizes your assessment in prose form. A clear scope-of-work document answers these questions: What does this facility do? What are the critical treatment steps and their regulatory targets? What safety hazards must be managed? What are the boundaries of the project — that is, what will you analyze and what is outside your scope?

Write in clear, direct sentences. Use your worksheet and PFD as source documents. Cite the regulatory authority for each requirement (EPA rule name, permit number if given, OSHA standard). A state reviewer reading your document should be able to confirm immediately that you understand the legal operating requirements of the facility.

Peer Review: Finding Gaps Before Submission

Two peers will review your document using a structured checklist. Their job is to find gaps — a missing unit process, an unlisted chemical hazard, a regulatory trigger you overlooked. Take written comments seriously and revise before submitting. In the field, a second set of eyes before a permit application or an inspection is standard professional practice, not a sign of weakness.