Exhibit A1 - SOW Replacement of MW-D1.pdf

SCOPE OF WORK

REPLACEMENT OF MW-D1

January 15, 2025

Fermi National Accelerator Laboratory (Fermilab) is looking to replace a deep till monitoring well and fix four stick-up well pads at its facility in Batavia, Illinois (Figure 1). The existing well is approximately 40 feet deep with a secondary surface casing made of PVC. Groundwater elevation and chemical analytical data suggest that the casing is not functioning properly, and the well may be serving as a conduit between the shallower and deeper till units. After the existing monitoring well is sealed and abandoned, a well with a similar screen interval depth will be installed within 10 feet of the original well. Also, the concrete pad at four existing stick-up monitoring wells is deteriorating and needs to be replaced. The installation activities and repair work are tentatively planned for the fourth quarter of 2024. Additional information and requirements are presented below.

Background

Fermilab is a Department of Energy Office of Science facility that is managed and operated by the Fermi Forward Discovery Group, LLC (FermiForward). Historically, a stream of wastewater from the Central Utility Building (CUB) was discharged to a tile field previously located in the project area. Discharge operations ceased and subsequent subsurface sampling indicated that the groundwater in the project area had been impacted with chloride and lead. The Illinois Environmental Protection Agency (IEPA) identified the area as a Solid Waste Management Unit (SWMU) and routine groundwater sampling has occurred since the mid- 1990s. The results of the sampling are reported to the IEPA on a semi-annual basis.

Work Location

The work area is located at the former CUB tile field in DuPage County; consequently, the Driller must submit appropriate well sealing forms (i.e., Water Well Sealing Application, Water Well Sealing Form/Well Location on Site) to the DuPage County Health Department. The proposed drilling location is depicted on Figure 2. The CUB tile field is accessible via asphalt-paved and gravel roadways, as well as two track pathways near the monitoring wells. The work area is located within a high-quality restored prairie.

Scope of Work

The scope of work consists of sealing and abandoning the current monitoring well and install a monitoring well discussed below.

1. Driller shall submit the Water Well Sealing Application and fee to the DuPage County Health Department.

2. Driller shall mobilize all necessary equipment and personnel to the job site. FermiForward can provide a laydown area to stage equipment and vehicles for the duration of the sealing and installation activities.

3. FermiForward will flag the proposed monitoring well location and mark subsurface utilities in the vicinity. Driller will not need to submit a public utility locate request (i.e., JULIE); however, Driller will need to hand clear or soft dig each proposed location to a minimum of five feet below ground surface (bgs).

4. The existing monitoring well MW-D1 shall be sealed and abandoned in accordance with Title 77 of Illinois Administrative Code (IAC) Section 920.120. The entire MW-D1 monitoring well must be over-drilled to ensure the secondary PVC casing and entire well construction to depth is removed.

The soil boring log and monitoring well construction diagram for MW-D1 are included on Figure 3.

5. The resulting borehole shall be sealed with neat cement grout or bentonite product from the bottom up using a tremie pipe method.

6. Following sealing and abandonment of MW-D1, the replacement well (i.e., MW-D7) shall be installed within 10 feet of the original well. FermiForward will determine the actual locations of the borings/wells based on utility and operational clearance.

7. A steel surface casing will be keyed into the top of the silty clay unit previously observed at approximately 18 feet below grade. FermiForward anticipates the steel casing will be six inches in diameter or greater to facilitate drilling beyond the surface casing and construction of a two-inch diameter monitoring well. The steel casing will be welded together on-site to ensure an adequate seal is provided between pipe sections and that migration of groundwater between aquifer units is prevented. The casing will be grouted in place from the bottom-up using a tremie pipe. The grout will be allowed to set for a minimum of 24 hours prior to advancing the boring further.

8. Once the casing is securely seated into the silty clay unit and set in grout, drilling can resume.

Continuous sediment sampling will be required between approximately 32 feet bgs and the boring’s terminal depth (i.e., 40 feet bgs). The terminal depth of the boring will be confirmed in the field by FermiForward personnel based on observations of the soil cores and desired monitoring well construction details. Split spoon, direct push tooling, or similar equipment will be used to collect the continuous sediment samples.

9. Driller shall install the monitoring well within the open borehole using new, Schedule 40, flush-joint threaded PVC screen and riser pipe. The well screen shall be five feet long and have 0.010-inch machine-cut slots. The anticipated well construction details are depicted on the attached IEPA Well Completion Report form.

10. Once the screen and riser pipe are installed and centered in the borehole, a sand pack shall be installed. The clean #20 quartz sand shall be placed around the well screen using a tremie pipe or positive displacement method. A weighted tape measure shall be used to ensure the material is not bridging. The sand pack shall be placed two feet above the top of the well screen.

11. A two-foot bentonite seal shall be placed on top of the sand pack. The bentonite shall be hydrated with potable water if necessary. The bentonite shall be placed using a tremie pipe. If poured from the surface a weighted tape measure will be used to endure the bentonite product (e.g., 3/8-inch chips) are reaching the appropriate depth.

12. The annular space above the seal shall be filled from the bottom-up with bentonite slurry grout.

The grout will be mixed at the surface and pumped through a tremie pipe until the grout reaches the top of the boring.

13. The wells shall be completed at the surface as “stick-up” wells. The top of the riser shall be approximately three feet above the surrounding grade. A vented J-plug must be supplied by the driller. A painted steel or anodized aluminum protective cover shall be placed over the PVC riser pipe and a concrete pad poured around the cover. Sand pack material shall be poured between the riser pipe and the protective cover to stabilize the pipe and discourage pest infestation.

FermiForward will provide locks for the protective covers. No protective bumper posts are needed at this time.

14. No less than 24 hours after installation, the wells shall be developed to remove residual well drilling fluids and to ensure the well screen is clear. The driller shall deploy a decontaminated well pump and new HDPE or LDPE tubing to the well screen interval and pump water from the well until it is clear, and the field parameters (pH, conductivity, and temperature) are stable. FermiForward will provide the equipment needed to monitor field parameters if necessary.

15. Driller will demobilize all equipment, excess materials, and personnel.

16. Driller will complete the Water Well Sealing Form/Well Location on Site and send it to FermiForward for review and submittal to the DuPage County Health Department.

In addition, Driller will replace deteriorating concrete pads at four existing monitoring wells during the same mobilization.

1. Driller will break up deteriorating concrete around the steel protective covers using hand tools and remove the debris.

2. Driller will reset the existing protective covers in new concrete.

Responsibilities

The Driller responsibilities include:

1. Driller will be responsible for submitting the Water Well Sealing Application form and all necessary fees to the DuPage County Health Department prior to conducting the work.

2. Driller will hand clear or soft-dig to five feet at each proposed drilling location.

3. Driller personnel will not have access to any buildings on-site and should make arrangements for portable washroom facilities to be delivered and removed from the property.

4. Driller personnel must attend site orientation prior to beginning work activities. FermiForward estimates the orientation will last approximately one hour.

5. Driller must don appropriate Level D personal protective equipment (PPE) including hard hat, safety glasses, hearing protection, cut resistant work gloves, nitrile or latex gloves, and steel- or composite-toe work boots. Driller is responsible for providing its personnel with PPE.

6. IDW including soil cuttings, drilling mud, and purged groundwater must be contained for off-site disposal. Driller must provide RFA with an estimated volume of IDW that will be generated when completing the scope of work.

7. Driller will be responsible for coordinating all appropriate permits and notifications to state and local officials necessary to complete the scope of work.

8. FermiForward defers the selection of drilling methods (e.g., roto-sonic, hollow stem auger) to the Driller; however, the methods and procedures must be sufficient to install a properly cased two-inch diameter monitoring well. Methods must be provided for FermiForward approval prior to award of the project.

FermiForward Responsibilities

1. RFA will mark subsurface utilities.

2. FermiForward will manage the profiling and disposal of investigation derived waste (IDW). Driller will be responsible for transferring IDW from the drilling locations to the disposal containers (i.e., lined roll-off boxes, totes) to be staged near the work area.