B08_140G0221R0025_Attch_1_Work_Statement.docx

Solicitation 140G0221R0025 Attachment 1

Performance Based Work Statement Removal of USGS Concrete Block Obelisk “Stilling Well” in Ottumwa, IA Background: A concrete stilling well was established on the Des Moines River at Ottumwa, IA. in 1963 by the United States Geological Survey (USGS). This structure was used for the purpose of measuring and recording stage. The structure was built using concrete blocks and would have been constructed to meet requirements conveyed in USGS publication TWRI 3-A7. This structure was abandoned by the USGS in 2012. The USGS abandoned the gage due to the unsafe conditions the structure posed to staff and the public. Severe deterioration of the concrete, holes in the block walls, and failing walkway due to severe rust lead to a very unsafe structure. In 2011 the city of Ottumwa turned the abandoned railroad bridge that the gage was attached to into a trail. With this construction of the new trail the city added an 8 ft. high fence to the bridge that closed off access to the abandoned USGS gage. The fence has made access to the structure much more difficult although we continue to see new graffiti on the abandoned structure. The structure is a public safety concern and a liability. Due to these factors the USGS Central Midwest Water Science Center (CMWSC) would like to have this structure removed. USGS wishes to have this structure safely removed and the waste materials properly disposed of. USGS has obtained NEPA categorical exclusion for the structure and may provide this to the contractor upon request.

Property Owner: The land is owned by the City of Ottumwa Iowa. The bridge itself is owned by Wapello County, IA.

City and County points of contact will be provided by the USGS to the awarded contractor upon request.

Description of Structure: The structure is a concrete block structure. There are access doors near the top and typically at the base at ground level when constructed. The lower access door is seized shut due to rust. The structure is generally 5.5ft wide. The height is approximately 30ft tall. Wall thickness is usually about 6”. There is a steel catwalk that extends from the trail to the vertical structure. Which should be removed as part of the demolition. The structure is defined as: the concrete obelisk stilling well and any footer, the steel catwalk bridge extending from the walking path to the obelisk structure, and the vertical steel supports and ladder and concrete footer that support the catwalk .

Figure 1: General construction specifications. Not to Scale. For reference only.

Location: USGS streamgage 05489500 Des Moines River at Ottumwa, IA. The stilling well and structure are located on the right bank, 15 feet downstream from the Colorado and Eastern Railroad bridge, and 815 feet downstream of the South Jefferson Street bridge in Ottumwa (Latitude 41.01077778, Longitude -92.41148889, North American Datum of 1983).

Figure 2: Location of USGS streamgage 05489500 Des Moines River at Ottumwa, IA.

Access: Possible option #1

Figure 3: Access, North side of bridge

Alternate Access: Possible option #2

Figure 4: Access, South side of bridge

Scope of Work:

1. Contractor shall obtain all necessary permits or permissions for access, removal, and disposal of the structure. Contractor shall provide copies of permits to USGS Technical Liaison (TL) and the Contracting Officer (CO)prior to notice to proceed for on-site demolition.

a. Obtain permits

b. Contractor shall be responsible for securing the site upon notice to proceed.

i. Initial access to site shall be provided through communication with the TL upon determination of start date.

ii. Contractor shall use their own locks or security devices to secure the site following initial access.

iii. Contractor shall notify TL upon completion of work so that TL may replace lock on fence gate.

2. Contractor shall perform demolition of the structure (as defined in Description of Structure), including the attached catwalk and catwalk support structure.

a. Structure and Catwalk must be demolished to at the base at least 1ft below the ground surface.

i. Contractor may cut the footer 1ft below grade and fill remaining void with gravel or other approved fill material per terms of the contractor obtained permit.

ii. Contractor may remove all concrete or other related material.

b. Contractor shall employ OSHA jobsite safety standards and requirements confined entry, heights, and near water work.

3. Contractor shall test site materials for potentially hazardous waste prior to commencing demolition.

a. Testing shall be performed by Industrial Hygienist contracted by the contractor.

b. Results of tests shall be provided to TL prior to commencing work.

c. TL will file results with USGS

d. Contractor shall file results with appropriate entities in accordance with locals, state, and Federal requirements.

e. Contactor shall remediate and properly dispose of any hazardous materials related to the demolition if present.

i. Contractor shall provide TL with documentation of amounts of hazardous materials disposed of as well as the location of disposal.

ii. TL will archive disposal documentation in the Local (CMWSC) Electronic Site File dedicated to the site.

4. Contractor shall provide removal of waste materials resultant of demolition of and related to the structure and catwalk

5. Contractor shall be responsible for disposal of the demolished material related to the structure

a. Contractor shall disposed of waste materials in accordance with any local, state, or Federal laws regarding construction material disposal and/or hazardous waste disposal if applicable.

6. Contractor shall be bonded and insured in accordance with the contract clauses.

7. Contractor shall communicate planned dates and related work for aspects of the demolition to the TL at least 3 days prior to the work being started. Contractor shall communicate plans with City of Ottumwa and Wapello County officials.

QUALITY ASSURANCE SURVEILLANCE PLAN (QASP)

The contractor is responsible for quality control for this project. As such, the contractor shall conduct its quality control procedures before contacting the USGS TL to begin the Government quality assurance inspection of the contractor’s performance. The Government is responsible for Quality Assurance (QA) and will inspect and verify that requirements as described above are being met. The TL will (1.) inspect the results of the material tests conducted by the Industrial Hygienist. The TL will (2.) verify the accuracy of the material disposal documentation with the disposal location owner for any potentially hazardous waste. The TL will (3.) inspect the final results of the completed project and assure that all related structure has been removed from the site and the site surroundings are left in a condition that is similar to before the work was performed.

Quality Standard of Acceptance, TL will:

1. Inspect Materials Test Results

a. Verify Materials tests were performed by a Certified Industrial Hygienist (CIH)

2. Verify the accuracy of material disposal documentation

a. Verify that if hazardous material was present as indicated by testing that the hazardous material was disposed of at a location that is lawfully designated as able to accept, handle and dispose of hazardous material. This will be verified by comparing contractor provided documentation of the disposal to information from collected from the disposal location for substantiation.

b. Documents will be verified for material type, weight, and proper disposal between contractor provided documentation and independent communication with the accepting location.

3. Inspect the final results of the work

a. Verify that all structures subject to the contracted work have been removed as conveyed in the statement of work.

b. Verify that there has been no significant damage to surrounding site conditions or damage to public or private property.

i. If damage is present, shall verify that the contractor has suitably remedied damage with those affected.

c. Verify that no unpermitted waste material or equipment is left on site at the conclusion of the work.

The TL will notify the contractor of substandard performance if/when the quality standards and or time standards are not met. The contractor will re-perform the task or remediate issues to meet or exceed the quality and time standards within 7 Days from the date notified at no additional cost to the Government.

Additional Pictures:

Steel walkway that connects concrete structure to railroad bridge.

Concrete structure adjacent to railroad bridge.

Steel ladder and concrete support attached to steel walkway.

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