CORPORATE SOCIAL RESPONSIBILITY REPORT A 2017 Report on Cornejo & Sons, L.L.C.

A LETTER FROM OUR PRESIDENT At Cornejo & Sons, we gladly embrace the vision laid out by Tom Hill, the CEO of Summit Materials, Inc. for our sustainability program. Our 500 employees and their families represent a large, diverse, and vibrant group in the larger Wichita area. Due to the nature of our activities, our entire workplace is within the Wichita area. Our workforce takes pride in the community and interacts with professionalism and courtesy on a daily basis. From construction sites to delivery or concrete mixer trucks, our distinctive lime green colors are on display everywhere in town. We are proud to be actively engaged in the business community, supporting the goal of making Wichita attractive to new development and investments. The company and many of our employees are also enthusiastically involved with charities, non-profits and schools that support the community. Finally, we are mindful of our responsibility to the environment and have generated many initiatives to show our commitment at many of our sites in and around Wichita. The following report illustrates the passion of our company and our employees for our community and the environment.

Georges Ausseil, President

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OVERVIEW

WHO WE ARE At Cornejo & Sons, we pride ourselves on strong community relations, environmental initiatives, and our employees. We value community education, partnering with Anderson Elementary, a local elementary school, by donating bicycles to students with high attendance rates. We also support students at Heartsprings, a local education center that provides equal opportunity education to students with special needs. To promote environmental sustainability, we have partnered with the Wildlife Habitat Council to promote native habitat as a part of our land reclamation efforts. Health and wellness of our employees is also a priority. The Cornejo Rollers bicycle team has promoted these initiatives over the years as we support community events such as Tour de Cure and Pedal Fest in Wichita. We believe our focus on community relations, the environment, and our employees will contribute to success for years to come at Cornejo & Sons.

WHAT WE BELIEVE We believe that doing the right thing environmentally, socially, and fiscally is what makes an outstanding company. Our Corporate Sustainability Mission is to incorporate social and environmental values into our business so that we have a positive impact, improving the places where we live and operate.

OUR LEADERSHIP TEAM GEORGES AUSSEIL President PAT SHORT Vice President Aggregates TIM ZYNDA Vice President Asphalt and Ready Mix SHARLA FRENCH Finance Manager

OVERVIEW

MICHELE WEDAN Human Resource Director JEFF BREMER Equipment Manager CARISSA CAVANAUGH Acting Safety Manager RANDY ROTHS Community Outreach Director

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A SHOUT OUT TO AN EXCELLENT DRIVER Cornejo & Sons recognizes Wangati Kinyanjui for his excellent performance and 10 years of service with the company as a CDL truck driver. After moving to the United States from Kenya over 15 years ago with his two children, Wangati obtained his CDL in 2001 and has pursued a lasting career in the industry ever since. His favorite part of working at Cornejo & Sons is working with the crew and building lasting relationships.

OUR EMPLOYEES Our goal is a safe, healthy and fulfilled workforce. Our people are our greatest asset and safety is our number one priority. We strive to be an employer of choice by providing a work environment that stimulates innovation, team spirit, engagement, and achievement.

OUR EMPLOYEES. OUR VALUES.

EMPLOYEE WELLNESS

As an employer, we strive to have employees that live the same values we align ourselves with. These values include: commitment to excellence, open and honest communication, cooperation, support and empowerment, sense of humor, compassion, respect and understanding, and flexibility.

Our wellness philosophy is designed with the long-term health of our employees in mind. A healthy employee is the most important part of a vibrant workforce.

SAFETY IS OUR #1 PRIORITY Safety is a core value at Cornejo and is part of everything we do. We are uncompromising in our commitment to safety and the well-being of our employees, customers, and communities. Our safety principles offer comprehensive sitespecific programs, ensuring common dangers don’t hurt our team. Recently, our safety leadership teams have taken our program to a whole new level. These teams take time away from their daily tasks to analyze, discuss, and ultimately reduce hazards. Safety leadership teams have developed dozens of exceptional projects, from entering and exiting work sites more safely, eliminating the need to climb on trucks to tarp or clean windows, and fostering more communication among road crews. Safety leadership empowers our employees to analyze everyday tasks to improve overall safety.

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In October 2017, we hosted our 3rd Employee Wellness Fair at Evergreen Park. With nearly 500 people in attendance, it was an opportunity for Cornejo to show our employees that their health is important to us. Attendees had an opportunity to enjoy lunch and meet with representatives from various organizations, including the American Diabetes Association, Grace Med, a local Chiropractor, the YMCA, Mid-American Credit Union, and the Wichita Fire Department. We also provided bounce houses and fun activities for the kids and families. Another important part of our employee wellness is our free wellness screening. We use those results to help our employees sustain or reach their personal health goals. It is our hope that these screenings will help employees catch health risks before they become a serious problem.

OUR EMPLOYEES

WINDFARMS We are proud to be a part of the clean energy movement with our participation in constructing the bases for four windfarms. Located in the heart of the nation’s wind corridor, Kansas is an ideal location for wind energy production and is currently ranked third in the nation for wind energy potential. This developing energy source presents opportunity for Kansas’ economy and developing industries to use cleaner, renewable energy sources.

700,000 TONS OF MATERIAL TRANSPORTED BY RAIL

TRANSPORTATION Transporting aggregates is heavy work. To lower our environmental impact, Cornejo & Sons rails aggregate material whenever possible. Last year we loaded more than 5,000 cars from our quarry, 2,000 cars from our sand plants, and 300 cars from our retail stone yard. That’s nearly 700,000 tons of material not transported by truck – reducing our impact on local roadways, traffic, and greenhouse gas emissions.

DUST CONTROL Dust control is a constant challenge at our aggregate stone yard. To mitigate the problem, we have installed a wheel wash system at the stone yard exit. Every truck leaving our stone yard passes through the wash system. This removes all dust and mud from the trucks, keeping the city streets clean. We hosted a meeting with the local neighborhood association. Everyone including representatives from the city of Wichita were very pleased with the results. This has been a welcome improvement to our stone yard and shows our commitment to being environmentally responsible.

WILDLIFE HABITAT We finished mining at our North Wichita Sand plant and have converted it into a wildlife habitat. We have installed four nesting boxes for songbirds, two raptor boxes, and four duck tubes for mallard ducks to nest in. The site is a popular birding area and we are happy to help improve this avian habitat. We have provided 2 brush piles for natural habitat for wild animals who need dense cover in which to hide from predators, rest, nest, and seek shelter from severe weather. Additionally, we have been planting milkweed in the area for monarch butterfly habitat.

REDUCING EMISSIONS We have transitioned all 3 of our asphalt plants from burner oil to natural gas, substantially reducing carbon dioxide emissions. We also used recycled oil to heat our shop buildings in the winter months and have instituted other company-wide programs to limit our emissions, including limiting vehicle idle time and encouraging paperless communications.

OUR ENVIRONMENT

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SHINGLES BEFORE

SHINGLES AFTER

Recycling Asphalt Shingle

395 tons used in 2017

REDUCE, REUSE, RECYCLE According to recent surveys conducted by the National Asphalt Pavement Association, 72M tons of asphalt pavements are put back to use in new pavements each year, greatly reducing the amount of material going to landfills. Cornejo & Sons is proud to participate in this effort, operating two recycling plants. In 2017, we recycled approximately 306,000 tons of asphalt and approximately 197,000 tons of concrete between both locations. Efforts like this reduce the amount of material sent to landfills while creating a marketable product.

Recycled

306K tons of asphalt in 2017

OUR ENVIRONMENT

Recycled

197K tons of concrete in 2017

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OUR COMMUNITY Our goal is to be a good neighbor. By partnering with our local communities and building public trust, we can do our part to have a positive impact in the places we live and work.

#ILOVEWICHITA

ANDERSON ELEMENTARY SCHOOL

Cornejo & Sons is proud to be an active part of the Wichita community. In conjunction with the Wichita Chamber of Commerce, we are part of the #ilovewichita campaign. To promote this, we had two of our dump trucks painted with the Wichita Flag and the logo of the Wichita Keeper of the Plains.

Cornejo & Sons is proud of our special relationship with Anderson Elementary School, located just 3 blocks from our main office. Every year, Cornejo & Sons helps to promote attendance by giving away a bicycle to a student with perfect attendance. Additionally, we participate in a yearly school supply drive and our annual adopt a school family for Christmas. This year, Cornejo and Sons also volunteered to help promote Junior Achievement. In addition to our partnership with the school, we are proud to partner with the United Way’s “Read to Succeed” program. This program focuses on helping children read at grade level by third grade, when students begin to transition from “learning to read” to “reading to learn.” Volunteer reading coaches are matched with at-risk students at targeted local elementary schools. They meet weekly with a student for 30 minutes to help them improve their reading skills.

We participate in many “Touch-a-Truck” events at local elementary schools.

The huge downtown Wichita Chili Cook-Off served 11,000 people. We made 15 gallons of chili.

Photo taken while doing company sponsored community service work in Houston after Hurricane Harvey.

OUR COMMUNITY

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CORNEJO MATERIALS

CDR

CMC

NORTH WICHITA SAND 3500 N. West Street Wichita, KS 6720 (316) 943-3500

NORTH CENTRAL Stone Yard 33rd. St. N. & Ohio Wichita, KS 67219

WEST ROBBINS 130 W. MacArthur Wichita, KS 67217 (316) 220-6150

CMC PLANT 1 3030 S. Madison St. Wichita, KS 67216 (316) 613-5208

KINGSBURY SAND 4601 N. West Street Wichita, KS 67205 (316) 220-3688

STONE YARD 3300 S. Hydraulic Wichita, KS 67216 (316) 220-3687

OXFORD SAND 1438 122nd. Rd. Oxford, KS 67119 (620) 455-3720

CMC GODDARD 1811 S. 135th. St. W. Wichita, KS 67235 (316) 613-5209

OXFORD SAND 1438 122nd. Rd. Oxford, KS 67119 (620) 455-3720

NW RECYCLE 3600 N. West Street Wichita, KS 67205 (316) 220-6183

LANDFILL 4250 W. 37th. North Wichita, KS 67205 (316) 220-3694

CMC NORTHSHORE 2460 N. Northshore Blvd. Wichita, KS 67205 (316) 613-5214

CORNEJO QUALITY Stone Durbin Quarry 1499 Dove Moline, KS 67353 (620) 647-3557

CMC ANDOVER 611 W. 13th. St. Andover, KS 6700

KS

E L D OR A D O EUREKA

CMC EL DORADO 1901 W. 6th. Ave. El Dorado, KS 67042 (316) 613-5210

A ND OVE R HOWA R D M OLI NE OXF OR D

CMC PLANT #7 1401 E 7th St Eureka, KS 67045

CMC PLANT #8 1610 Killdeer Howard, KS 67349

Wichita

A subsidiary of Summit Materials, Inc.