CSC was selected to oversee and certify that all remediation work was completed in accordance with the Remedial Action Workplan (“RAW”) approved by the California Department of Toxic Substances Control for a nine-acre site. Over 1,400 soil samples were collected and analyzed to confirm that all contamination was removed. CSC oversaw three groundwater monitoring wells and five nested soil vapor monitoring probes.  During all work activities, CSC monitored air quality using one upwind instrument and two downwind instruments for obtaining continuous real-time data for particulate emissions; one sensitive receptor for obtaining continuous real-time data for particulates; one hand-held particulate monitor for assessment of work areas; one meteorological station to continuously monitor weather conditions, including wind speed and direction; one portable appropriately calibrated photo-ionization detector (PID); and one portable multi-gas meter to monitor for methane and hydrogen sulfide.

As a representative of the school district, CSC was responsible for ensuring that work activities were in compliance with all applicable and relevant regulatory requirements.  CSC:

  • Prepared a site-specific health and safety plan for use by CSC staff and all of its subcontractors
  • Documented that the demolition contractor had prepared a site-specific HASP for use by its employees and all of its subcontractors
  • Delineated excavation areas and marked sampling locations with stakes/flags and/or high visibility paint.
  • Ensured that (1) utility clearance (identification of utility or other hazardous underground obstacles) was conducted by the Demolition Contractor prior to initiating any soil intrusion or subsurface activity; (2) the Demolition Contractor protects structural features and public utilities from damage during implementation of the removal action; (3) the demolition contractor maintained site security fences during the implementation of the subject removal action, including maintenance of windscreen on all perimeter fence line
  • Implemented, monitored and reported all meteorological, dust, methane, hydrogen sulfide and volatile organic compound (VOC) air monitoring results during demolition and excavation as required in the RAW
  • Maintained a field logbook pursuant to the RAW to document, among other things, observations, personnel onsite, equipment arrival and departure time, work hours, and other vital project information pursuant to the RAW.
  • Maintained chain of custody documentation for any samples sent offsite for analysis
  • Photographed all completed excavations and other milestones which served as verification of RAW implementation and inclusion in the Remedial Action Completion Report
  • Prepared a daily summary of activities for the Site that included; a description of the areas excavated (dimensions, volume of soil excavated, etc.), the quantity of soil shipped off-site for disposal, the number of trucks used to transport the soil for off-site disposal with the corresponding manifest number, the number and locations of confirmation samples collected, and the available analytical results
  • Prepared a figure (or figures) of the excavation areas, step-out excavations, confirmation sample locations and analytical results, which were updated on a weekly basis
  • Provided LAUSD-OEHS with weekly updates on the status of work
  • During excavation, ensured that mitigation measures such as water spray or vapor suppression was implemented by the Demolition Contractor to minimize the potential for fugitive dust and/or VOC vapor
  • Confirmed compliance with the components of the approved Transportation Plan provided in the RAW
  • Verified that the demolition contractor used smooth (continuous edge) excavation buckets for all excavation areas
  • Confirmed that the excavation equipment was decontaminated prior to mobilization to the site, in between excavations and prior to demobilization from the site
  • Confirmed that the demolition contractor segregated non-hazardous, California-hazardous and RCRA soils during excavation and/or stockpiling activities at the site
  • Monitored temporary onsite soil stockpiles to verify placement on an impermeable surface (pavement, double plastic sheeting, etc.) with berms and covering of all stockpiles during non-work hours with plastic sheeting weighted with sandbags to fugitive dust/vapor generation
  • In consultation with the remediation contractor, obtained approval from the school district prior to implementing change orders due to field variances
  • Collected confirmation and step-out samples as detailed in the RAW
  • Verified that the demolition contractor obtained all required waste manifest documentation from both the school district and the receiving facility (TSDF, landfill, etc.), prior to offsite shipment of soils
  • Signed manifests on behalf of the school district and maintained a copy of the manifest/shipping document for each truck load of soil transported out of the job site
  • Conducted, tracked, and reported the import/export and waste profiling sampling and analysis at the site during the implementation of the subject RAW
  • Verified that the demolition contractor (1) met all profiling requirements for the specified receiving facility (TSDF, landfill, etc.); (2) obtained the approval of the school district’s Environmental Compliance Manager prior to export; and (3) the demolition contractor transported all wastes pursuant to the RAW Transportation Plan
  • Ensured that all excavations greater than four feet in depth were safety sloped as soon as practical after DTSC provided unofficial clearance of said excavation
  • Obtained all permits and permission necessary to properly abandon three (3) groundwater monitoring wells and five (5) nested soil vapor monitoring probes
  • Prepared a Removal Action Completion Report in accordance with the RAW that required evaluation of over 3,000 pages of laboratory data
  • Conducted several months of air monitoring for dust, and VOC emissions during school construction

We have been more than pleased with the service provided by Clark Seif Clark Environmental. This is our second contract with them and their professionalism is top notch. I can only hope they are the successful bidder on our next contract as well.

Jim B.
Chief of Plant Operations II

Just want to say Thank You.
Your lunch presentation was nothing less than awesome. Your professionalism, enthusiasm, and knowledge energized the class. We look forward to a continued relationship with you and your organization. Thanks again,


I just wanted to take a moment to say Thank You for on excellent presentation on Saturday.
My technicians and I were all very impressed by what we learned, and I received some very positive feedback from the other offices in attendance. Being in the water damage business, we are frequently faced questions about mold growth from water damage customers, insurance personnel and property managers. Your presentation, visual aids and handouts were well planned and targeted to our particular interests. I think we can now address the topic with a greater sense of confidence (and a little less guesswork!). I am sending copies of your presentation packet to everyone who attended along with request for feedback. Thank you again for a well done presentation. I look forward to working with you on future projects.


Wanted to take a few minutes to express our "thanks" for the wonderful presentation that Derrick Denis gave at our office meeting last month.
We had over twenty agents in attendance and they were all very impressed with no only the knowledge, but the informative way Derrick presented the material. The Mold Disclosure Issue is one of the most confusing that we as real estate practitioners have had to deal with in a number of years. Derrick made the confusion somewhat less on our part and gave us all a better understanding if just how we should present this problem to our clients. Again, thank you for having such a wonderful person representing your company. We would not hesitate to use or recommend your firm to our clients.


Thank you again for being part of the Los Angeles County East Chapter (LACE) luncheon program last week.
We greatly appreciated your understanding of our audience and what they needed to know. Both your presentation and responses to the participants questions were right on target.


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