Sound Survey Results for MARA’s Granbury Data Center Operations: Sound Levels Well Below Legal Compliance Limits

• Independent, Third-Party Sound Survey Confirms Compliance with State and County Noise Regulations

• Sound Levels Reduced from 78 dB to 63 dB Since MARA Took over Operational Control

• MARA Continues To Enhance the Hood County Data Center
  

As part of our commitment to transparency and being good, long-term neighbors, we are sharing the findings from an independent, third-party sound survey conducted around our data center operations in Hood County, Texas. We believe this survey provides a clear and factual representation of the sound levels associated with our facility. According to the survey, all the levels measured around the facility are well below the state and county law noise limit of 85 decibels (dB).

‍

We have also included additional sound survey results that were collected by an independent noise evaluator during the first week we assumed operational control of the data center. These results were compared with the latest survey to measure the progress of our implemented initial improvements. Our findings indicate that sound levels have declined from approximately 78 dB to 63 dB since MARA took ownership of the data center. We are continuing to take proactive steps to further enhance the site.

‍

The timeline and roadmap outlining our efforts to enhance our operations and support the community can be explored in more detail here. The full results and details of the sound survey conducted by the independent, third-party can be found here.

How Are Sound Levels Measured?

Sound is measured in decibels (dB), a unit that quantifies the intensity or loudness of sound. Various common sounds and their respective decibel levels are shown in Figure 1 below.

‍

Sources: Absolute Noise Control, Texas Constitution and Statutes, Builder, Granbury Code of Ordinances

‍

Independent, Third-Party Sound Survey Overview and Results

The sound survey, conducted by Absolute Noise Control (ANC) on July 18, 2024, recorded sound levels at various locations while the data center was operating. The data center is located on Mitchell Bend Hwy, approximately 0.44 miles northeast of Contrary Creek Rd and about 260 feet west of the nearest residential properties. To measure the impact on nearby areas, sound receivers were placed at 11 different locations around the facility while the data center was operational. The figures reported are 15-minute average sound levels.

Source: Absolute Noise Control

‍

The sound levels recorded at the 11 locations around the Hood County data center indicate that all locations have sound levels well below the state and county limit of 85 dB. As part of our commitment to transparency, we have also voluntarily compared our sound measurements to Granbury’s quiet hours limit, even though this limit does not apply to our operations since the Hood County data center is located outside of Granbury. Even when compared to Granbury’s noise limit during quiet hours of 65 dB, the sound measurements near the data center are all within acceptable limits.  

Sources: Absolute Noise Control, Texas Constitution and Statutes, Builder, Granbury Code of Ordinances

MARA’s Sound Survey Results after Assuming Operational Control of the Hood County Data Center

In addition to the recent sound survey conducted by Absolute Noise Control, we also contracted Cerjan, another independent noise evaluator, to conduct a sound survey the week we assumed operational control of the data center. To better understand the progress we have made since taking over operational control of the data center, we compared the results from the initial survey by Cerjan at location PL03 with the recent results from Absolute Noise Control at location 2, which we believe to be the closet locations for a fair comparison (see figure 5). Based on this comparison, as of July 18, 2024, our operations have achieved a significant reduction in sound levels:

• Sound level at location PL03 when MARA assumed operational control: 78 dB

• Sound level at location 2 following MARA’s initial improvements as of July 18, 2024: 63 dB
  ‍

Sources: Texas Constitution and Statutes, Builder, Granbury Code of Ordinances, Cerjan, Absolute Noise Control, MARA

‍

Sources: Cerjan (left), Absolute Noise Control (right), MARA

‍

Since taking ownership of the site, we have taken several steps to enhance operations. The data from the sound studies indicates that these initiatives have been effective. The details are provided below.  

‍

MARA’s Recent Improvements

• January 2024: MARA acquires the Hood County data center.

• March 2024: Eight air-cooled containers are deactivated.

• April 2024: MARA officially begins operating the Hood County data center.

• June 2024: MARA has deactivated a total of 30-50 air-cooled containers at the site.

• July 2024: MARA has deactivated a total of 70-90 air-cooled containers at the site.

While we have made notable progress, we are continuing to take steps to further enhance the data center for the betterment of the community.  

‍

Future Sound Mitigation Plans (dates are subject to change)

• August 2024: Breaking ground on the sound wall.

• August 2024: Converting 20% of the site to liquid immersion cooling.

• September 2024: 30% of the site is expected to be converted to liquid immersion cooling.

• October 2024: Updates to the sound wall are expected to be completed.

• October 2024: 40% of the site is expected to be converted to liquid immersion cooling.

• November 2024: Start planting trees and enhancing landscaping.

• December 2024: 100-110 air-cooled containers are expected to have been deactivated.

• December 2024: 50% of the site is expected to have been converted to liquid immersion cooling.

‍

We care deeply about the communities in which we operate, and we want to hear from you. If you have any questions, concerns, or suggestions, please feel free to contact us at granbury@mara.com.  

Measuring Decibels in this Report

Sound is measured in decibels (dB), a unit that quantifies the intensity or loudness of sound. The studies and figures shown in this article use the "A-weighted" decibels (dBA) scale. dBA is frequently used because it reflects the sensitivity of the human ear to different frequencies of sound and is therefore considered to be a more accurate measure of perceived loudness for humans.  

‍