What We Do

What sets Clark Seif Clark apart from other environmental consulting firms is the knowledge and training of our people. We believe in science-based protocols and in cross-training all our personnel so that they are both thorough site investigators and knowledgeable compliance experts.

Unlike many environmental consultants, CSC also has a strong background in engineering. Architects, builders, contractors, developers and realtors all appreciate this expertise because we fully understand the challenges they face daily.

CSC moves quickly and performs jobs right the first time. We conduct thorough investigations, write detailed reports and provide expert legal testimony if necessary. Most importantly, however, CSC will see your project through to completion. We know that the job is never finished until the air is cleared of all environmental issues.

We are certain of our clients’ expectations. Our goal is to exceed them.

Mission Statement

The mission of CSC, Inc. is to protect the health and safety of people and the environment through the use of innovative and sustainable measures, and to provide economically viable solutions using the best environmental consulting practices.

Vision Statement

To build a national company that provides a wide array of services in the health & safety, engineering and environmental fields.

Our vision is accomplished by using the PRIME approach:

  • Promote ourselves as the very best at providing a wide range of technical services within our field of expertise.
  • Reinvest in acquiring the best available talents to help us achieve our vision.
  • Inspire our employees through hard work, dedication, and integrity.
  • Motivate our employees to pursue higher education and by providing them with the tools needed to succeed, by assisting them in setting achievable goals, and by rewarding them for their efforts.
  • Excel at providing unparalleled services based on a strong understanding of science and regulatory standards at a price that is both valuable to our clients and profitable to our company.

Core Values:

  1. Honesty – CSC employees are honest individuals who seek the truth in every project.
  2. Fairness – CSC employees are fair and unbiased.
  3. Respect – CSC employees respect people and the environment.
  4. Integrity – CSC employees are consistently abiding by high set of principles and values.
  5. Concern for Others – We are genuinely concerned for others’ interests.

Contact Us

For over 20 years, Clark Seif Clark’s highly qualified team has been providing a broad range of environmental compliance services to meet complex environmental and safety issues, focusing on environmental assessments, investigations, remediation work plans and field oversight for private and public sector clients.

Contact us to learn how we can identify the best solution to your environmental concerns.



Franco Seif, PE

President and CEO

Franco Seif is President and Chief Executive Officer of Clark Seif Clark, Inc. (CSC). He is also a co-founder of CSC.Franco been a leader in the environmental and engineering industry for over 3 decades. He started his environmental and engineering consulting career at Camp Dresser & McKee, Boston, MA, in 1985. In 1987 he worked as a consultant for EPI, Center, a small industrial hygiene company, Santa Monica, CA. In 1990, Mr. Seif started an environmental consulting firm, Californian Environmental Consultants, that provided asbestos, indoor air quality, and Phase I & phase II environmental site assessment services to a small group of clients. In 1996, Mr. Seif joined forces with Brian Clark and Robert Clark to form CSC.

Mr. Seif is also active in the community. He sits on the board of directors of St. Anne’s, a non-profit organization that provides care to abused young pregnant, mothers and their babies. Mr. Seif also sits on the advisory committee of the American Council of Accreditation and Certification (ACAC), a certifying body for the indoor air quality professional.

Mr. Seif hold a bachelor’s degree in civil engineering from Northeastern University, Boston, Ma, and a masters of science degree in engineering management from Drexler University, Philadelphia, PA. He hold a professional engineering registration in the State of California, and he is an asbestos consultant with the California Occupational, Safety and Health Administration.

Robert Clark

Vice President of Indoor Environmental Quality

Robert Clark is the Vice President and General Manager of Clark Seif Clark, Inc. (CSC). He is also a co-founder of CSC. In 1985 Mr. Clark started his career with Watt Industries (Housing Developer) in the Southern California High Desert. In 1994 he started his career in the Environmental Business with brother Brian Clark company, Clark and Associates, performing Asbestos inspections related to the 1994 Northridge Earthquake. In 1996 he co-founded CSC and continues to work to provide superior environmental services for CSC clients.

Mr. Clark is licensed general contractor with the State of California. He is a California certified Asbestos Consultant, Lead Inspector/ Assessor, and Lead Project Designer.

Derrick Denis

Vice President of Indoor Environmental Quality

For over 21 years Mr. Derrick A. Denis has provided professional environmental consulting and industrial hygiene services. Since earning a B.S. degree in Environmental Science from Phillips University in Oklahoma, Mr. Denis has worked in both environmental consulting and remediation across the United States. Mr. Denis holds or has held numerous industry-relevant certifications, including but not limited to, Council-Certified Indoor Environmental Consultant (CIEC) and Certified Indoor Air Quality Professional (CIAQP). Since 2001 Mr. Denis has operated in the capacity of Vice President of Indoor Environmental Quality for Clark Seif Clark, Inc. (CSC).

Mr. Denis remains an active participant in the IEQ industry. Mr. Denis serves on the Board of Directors of the Indoor Air Quality Association (IAQA). He is Chapter Director for the Phoenix IAQA Chapter. Historically, Mr. Denis served on the Board of Directors for the Environmental Information Association Arizona Chapter (EIA-AZ) as well as the Advisory Board of the American Council for Accredited Certifications (ACAC). Mr. Denis was an adjunct faculty member of the Maricopa County Community College District (MCCCD), where he taught indoor environmental quality through Phoenix College Downtown. Mr. Denis is an instructor for the Institute for Facility Management Education at the Electric League of Arizona (ELA), where he instructs on the subjects of IEQ and environmental health and safety (EH&S).

Bill Jones, CIH, CSP, CPE

Vice President of Industrial Hygiene

Bill Jones is Vice President of Industrial Hygiene for Clark Seif Clark, Inc. His career of over 30 years as an environmental health and safety professional has included consulting as well as working for major oil and gas and aerospace companies. He has held Environmental Health and Safety management positions at the Northrop B-2 Division, Gencorp Aerojet in Azusa, CA (leading Aerojet to become the first aerospace company in California to achieve the coveted VPP Star Status), Bureau Veritas North America, Inc. and Total Safety U.S., Inc.

Bill has a Master of Public Health from Oklahoma University, a bachelor of science in chemistry from The University of Central Oklahoma and a bachelor of science in biology from Oklahoma State University. Bill is a certified industrial hygienist, certified safety professional and certified professional ergonomist.

He has been active in local sections of the American Industrial Hygiene Association (AIHA) and local Chapters of the American Society of Safety Engineers (ASSE). He served on the Board of Directors of the Oklahoma Section and the Southern California Section of AIHA (Past President SCAIHA). He is also Past President of the Orange County Chapter of ASSE.

Jeff Bannon, PG

Vice President of Environmental Services

Jeff joined CSC in June 2015 after serving nearly 28 years at a national engineering firm. Skills developed in his former capacity as Principal Project Manager and Office Manager provides ideal qualifications to lead our subsurface investigation/remediation group. He has directly managed several major projects and programs for a diverse customer base including the Federal government (US Navy, US Forest Service, Army Corps of Engineers), local governments (public works, port authorities, water districts) and private customers across the country. He has a proven track record in managing complex, multidisciplinary projects involving soil, soil vapor, groundwater, surface water, air and contaminated building materials on a wide-range of contaminants. He has served as project manager and/or technical manager on hundreds of assessments ranging from small, initial assessments (Phase Is) through multimillion dollar soil and groundwater investigations and cleanups. He is extremely competent at understanding the life-cycle of environmental projects, and the interrelation of technical objectives, regulatory requirements and cost implications in completing projects.

Jeff is Vice President of Environmental Services at CSC. He earned a B.A. in Geology from the University of Northern Colorado and M.S. in Geology from the University of Southern California, and is a California registered Professional Geologist (1992).

Client Testimonials

We strive to meet and exceed our client expectations at Clark Seif Clark

I just wanted to thank your staff here in town for helping ati out on all of these jobs over the holiday weekend.
Again and again, you guys never fail to come through in a pinch. Again thanks for doing what you do.


The work product you provided was excellent, and the first call I will make will be to you if opportunity arises.
The assignments I have been working on have had a hygienist involved when received. I do look forward to working with you again. Thank you.

Your contribution to the success of EIA 2008 was invaluable and the Environmental Information Association sincerely thanks you. Your presentation was a credit to the Association, and your participation strengthens EIA�s position as a primary information resource for our industry. Thank you again for your participation.


I applaud you for your hard work and dedication to bring this subject (mold) into the light for many of us who have had no earlier experience with mold.
I can tell you from my perspective, it is a challenge I’d much prefer to have good people behind me to correct. Yours Truly,


Wanted to take the time to let you know how much information I received from your presentation.
That has been the most complete scope of the mold problem that I have heard. I am sure that your expertise is going to be much in demand in our industry.


Office Locations

Los Angeles

Mailing Address:
P.O. Box 4299
Chatsworth CA 91313

Physical Location: Map
21732 Devonshire Street, 2nd Floor
Chatsworth CA 91311

Contact Info:
Franco Seif – Email
Phone: (800) 807-1118
Fax: (818) 727-2556

Long Beach

Location: Map
4010 Watson Plaza Drive, Suite 170
Lakewood CA 90712

Contact Info:
Norman Kramer – Email
Phone: (562) 435-8080
Fax: (562) 590-8795


Location: Map
3373 Sierra Oaks Drive
Sacramento, CA 95864

Contact Info:
Robert Clark – Email
Phone: (800) 807-1118

Chandler, Arizona

Location: Map
7302 W. Chicago Street
Chandler AZ 85226

Contact Info:
Derrick Denis – Email
Phone: (480) 460-8334
Fax: (480) 460-8335

San Diego

Location: Map
11315 Rancho Bernardo Rd., Suite 150
San Diego CA 92128

Contact Info:
Norman Kramer – Regional Manager – Email
Phone: (858) 675-1088
Fax: (858) 675-1033

San Francisco Bay Area

Location: Map
275 Rose Avenue, Suite 206
Pleasanton CA 94566

Contact Info:
Robert Clark – Email
Phone: (925) 931-0100
Fax: (925) 931-0108

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