Scope of Services

Task 1: Work Plan

A Work Plan was created prior to the site investigation, which contained the project description, site background information, project management guidelines, and field and laboratory methods and procedures.

Task 1.1: Sampling and Analysis Plan (SAP)

The SAP is included in the Work Plan. The SAP consists of field sampling protocols, laboratory analysis procedures, and quality assurance and control measures.

Task 1.2: Health and Safety Plan (HASP)

The HASP is included in the Work Plan. The HASP consists of safety and health administration, a hazard assessment and required personal protective equipment (PPE) for physical, chemical, and biological hazards, training requirements for the NAU lab and XRF, site control and operating procedures, personal decontamination procedures, and emergency response procedures.

Task 2: NAU Lab Binder

The team had to create a lab binder to gain access to the Environmental Engineering Laboratory facility.

Task 3: Site Investigation

The team conducted a site investigation on January 14-15, 2022 to collect soil samples as outlined in the Work Plan. The site investigation also allowed the team to perform a flora and fauna survey and to gain a better understanding of the mechanisms by which offsite contaminant migration may occur. The team collected a total of 46 soil samples from the site, including 28 grid samples, 13 hotspot samples, 3 background samples, and 2 field duplicates.

Task 4: Sample Analysis

Soil samples were analyzed with X-Ray Fluorescence (XRF) analysis to quantify concentrations of heavy metals at the site. The data collected from the sample analysis was compared to the Arizona Soil Remediation Standards (AZSRS), with human health contaminants of concern (COCs) identified as the contaminants whose concentrations exceed the standards. Ecological COCs were determined by comparing the XRF data to the EPA Ecological Soil Screening Levels (Eco-SSLs).

Task 4.1: Soil Sample Drying

To perform XRF analysis, the soil samples were first dried using ASTM Method D2216-10.

Task 4.2: Soil Sample Sieving

After drying, samples were sieved so only particles 250 µm or less were collected, in accordance to ASTM Method D6913.

Task 4.3: XRF Analysis

An XRF Analyzer was used to test for heavy metals in each soil sample. Each sample was divided into 9 subsamples, and the highest and lowest subsample readings were discarded. The remaining values were averaged to report a single concentration for each heavy metal.

Task 4.4: Identification of COCs

The results of the XRF analysis were compared to the AZSRS and EPA Eco-SSLs to identify the human and ecological health COCs at the site. The human health COCs Include lead, arsenic, and antimony. The ecological COCs Include lead, arsenic, zinc, copper, chromium(III), antimony, cadmium, and manganese.

Task 4.5: Inductively Coupled Plasma Emission Spectroscopy (ICP) Analysis

Confirmatory ICP analysis was outsourced to Western Technologies to verify the XRF results for arsenic. The correlation found between the XRF and ICP results was used to correct all XRF arsenic data.

Task 4.6: Correlation Curves

A correlation curve was created between the results of the XRF and ICP analyses. All XRF arsenic data was corrected based upon the ICP results.

Task 4.7: Soil Data Distribution

The soil data distribution was determined for lead, arsenic, and antimony using only grid sample results. The concentrations of all COCs were shown to be log-normally distributed.

Task 4.8: Spatial Distribution Maps

Spatial distribution maps were created to provide a visual representation of lead, arsenic, and antimony contamination at the site.

Task 5: Human Health Risk Assessment

A human health risk assessment was conducted to determine potential health risks associated with the site and if remediation is needed. The human health risk assessment includes exposure assessment, toxicity assessment, and risk characterization. Risk due to lead exposure was characterized with EPA pharmacokinetic models, ALM and IEUBK, which assess the distribution of lead as it travels through the body based upon the exposure scenario. Background risk was considered during risk characterization.

Task 6: Ecological Risk Assessment

A qualitative ecological risk assessment was performed to approximate risks to the environment. The information gathered from the flora and fauna survey was combined with outside research on local ecology to assess how the site may be impacting the local ecosystem.

Task 7: Contaminant Migration Assessment

A contaminant migration assessment was conducted to determine if COCs are migrating offsite or to potential receptors.

Task 8: Project Impact Assessment

The project evaluated environmental, societal, economic, and human health impacts associated with a “do nothing’ alternative at the site.

Task 9: Project Deliverables

Task 9.1: 30% Submittal

The 30% submittal includes the 30% report and presentation.

Task 9.1.1: 30% Report

The 30% report provided details of Tasks 1-3.

Task 9.1.2: 30% Presentation

The 30% presentation discussed the progression of the project at 30% completion.

Task 9.2: 60% Submittal

The 60% submittal includes the 60% report and presentation.

Task 9.2.1: 60% Report

The 60% report provided details on completed Tasks 1-4.

Task 9.2.2: 60% Presentation

The 60% presentation discussed the progression of the project at 60% completion.

Task 9.3: 90% Submittal

The 90% submittal includes a draft of the final report and draft website of the project.

Task 9.3.1: 90% Report

The 90% report provided details on completed Tasks 1-8.

Task 9.3.2: 90% Website

The 90% website is a nearly completed project website with all supporting documents and graphics. The website will not be made public.

Task 9.4: Final Submittal

The final submittal contained all required project deliverables.

Task 9.4.1: Final Report

The final PA/SI report contained of all report deliverables.

Task 9.4.2: Final Presentation

The final presentation showcased the project at 100% completion, with details of the site, analysis, and remediation recommendations.

Task 9.4.3: Final Website

The final website included complete project information, supporting documents, and graphics. This website will not be published and will be for internal use only.

Task 10: Project Management

Task 10.1: Meetings

Scheduled meetings occurred within the team and with the grading instructor/technical advisor, and client. Regularly scheduled team meetings were held to ensure the project timeline was being met, individual assignments were completed on schedule, and to review project needs as the project progresses. Weekly meetings were scheduled with the technical advisor to ensure the project is following appropriate technical guidelines for meeting the client’s needs and expectations.

Task 10.2: Schedule Management

The schedule was used to ensure individual and team assignments and project milestones are completed on time as per the Gantt Chart.

Task 10.3: Resource Management

The staffing plan, expenses, and materials were tracked to ensure the project budget was not exceeded.

Exclusions

Water and air sampling were outside the scope of this PA/SI. Additionally, the project did not include remediation options or legislative consequences and limitations of the remediation efforts that might occur after the PA/SI.