Planning commission recommends CUP for Smith Valley dairy methane digester after state safety review

The Lyon County Planning Commission voted 7-0 on May 13 to recommend that the Board of County Commissioners grant a conditional-use permit for a methane (biogas) digester already installed at a Smith Valley dairy, after staff said state regulators flagged the site for additional review.

Lucas Carrel, senior planner, told the commission the digester sits inside a larger 311-acre dairy and that the digester tank has a liquid volume "approximately 2,200,000 gallons." He said the county issued building permits for the structure in 2021 but those permits have since expired and that the Nevada Division of Environmental Protection's Chemical Accident Prevention program (CAP) told county staff in November 2023 that a local conditional-use permit is required for this kind of operation.

Why it matters: the digester produces methane from dairy manure and the CAP program treats the product and some associated materials as hazardous for storage and transport. That places safety, air-quality and fire-suppression review primarily with state regulators while leaving the county responsible for local land-use impacts such as truck routes, lighting and noise limits.

In his staff presentation, Carrel described site context and recommended mitigation language for the commission to include if it forwards approval. He said the digester subsystem is located on about 6.84 acres within the larger dairy, the property is zoned Rural Residential 20-acre (R R-20) and the county's master plan designates the parcel as agricultural. Carrel said the methane facility was previously treated as "accessory" to the dairy operation in earlier county reviews, but that the CAP program's rules now require a conditional-use permit.

Commissioners pressed staff and the applicant on safety, containment, noise, lighting and truck routes. Carrel said the applicant agreed to conditions that would require tanker trucks to use the better-maintained Honeywell Lane rather than a lesser-improved road identified by some residents, and that staff would seek noise and lighting standards drawn from county industrial code. Carrel also said the county could require a sound study paid for by the operator if a verified code-enforcement complaint arises.

Dominion Energy project manager Jamie Jacobs, representing CEA Dairy RNG Nevada LLC, described site safeguards. "I will confirm that the the the tank is, does have an internal liner, to protect against that. We do conduct leak tests both with water and with smoke to make sure that that nothing is leaking out of there," Jacobs said. He also confirmed the site contains compressors and pumps associated with the biogas upgrading and truck-loading equipment and acknowledged those units are likely the primary onsite noise sources.

Gavin Anderson, Lyon County community development director, told the commission the county can require conditions and, if necessary, later revoke approval if conditions are not met. "We could have that privilege, within code as an allowance to move those ADRs or to a condition use permit process to the commission," Anderson said, referring to administrative design-review authority and the ability to escalate review to elected officials when warranted.

Key clarifying details from staff and the applicant included: - Tank capacity: approximately 2,200,000 gallons. - Digester footprint: about 6.84 acres inside a ~311-acre dairy. - Zoning: rural residential (R R-20); master plan: agricultural. - Initial construction: Lyon County building permits issued in 2021 (now expired). - State oversight: Nevada Division of Environmental Protection Chemical Accident Prevention (CAP) program notified county in Nov. 2023 that a CUP is required. - Trucking: staff estimated roughly one tanker truck trip per day; the commission required that tanker traffic use Honeywell Lane where feasible.

Discussion versus decision: commissioners debated conditions on routing, noise testing and enforcement mechanisms; staff and the applicant said they were amenable to adding lighting and access conditions and to work with fire and CAP regulators on technical safety requirements. The planning commission's formal action was only to forward a recommendation to the Board of County Commissioners; CAP, the fire district and other state agencies retain independent permitting and technical review authority.

Votes at a glance: Planning commission recommendation for CEA Dairy RNG Nevada LLC conditional-use permit (recommissioning of an anaerobic digester for methane production). Motion to forward approval as recommended (staff findings H and G) carried. Outcome: recommended for approval; vote: 7 yes, 0 no, 0 abstain.

Where things go next: the recommendation moves to the Lyon County Board of County Commissioners for final action; separate state permits and reviews (NDEP/CAP, air-quality, fire district) remain required before full operation under county code and state regulations.

Community context: nearby residents raised concerns about noise, nighttime lighting, road wear and safety; commissioners asked staff to include enforceable language in the CUP conditions to allow revocation or required corrective actions if conditions are violated. The applicant said it would cooperate with county and state reviewers and emphasized existing containment and testing protocols.

The planning commission's record shows the digester already exists on the property, staff described additional submissions that will be required for building, fire and state review, and the commission's 7-0 recommendation sends the matter to the Board of County Commissioners for final decision.