City of San Diego ADDENDUM âBâ
City of San Diego ADDENDUM “B” FOR MBC ACCESS ROAD DRAINAGE IMPROVEMENTS BID NO.: SAP NO. (WBS/IO/CC).: CLIENT DEPARTMENT: COUNCIL DISTRICT: PROJECT TYPE:
L-12-3794-DBB-B B-00316 2011 7 CA
For which proposals will be received at the Public Works Contracting Group, 1200 Third Avenue, Suite 200, San Diego, California, until 1:30 PM on November 1, 2011. A.
CHANGES TO CONTRACT DOCUMENTS The following changes to the Contract Documents are hereby made effective as though originally issued with the bid package.
B.
ADDENDUM “A” 1. To Question and Answer 5, DELETE in its entirety and SUBSTITUTE with the following: Q5.
What is permanent hydroseed mix specification? Do you want tackifier? Is this an irrigated or non-irrigated mix? Is there maintenance expected of contractor after hydroseeding is done?
A5.
Project re-vegetation requirements and hydroseed mix shall be per the attached approved Minimum Seeding Requirements Plan, page 2 of 2 of this Addendum. Contractor shall be responsible to establish vegetation to 70% coverage level. Following this, City or Caltrans will take over maintenance for re-vegetated areas.
Tony Heinrichs, Director Public Works Department Dated: October 24, 2011 San Diego, California TH/nb/cg/ez/ls
October 24, 2011 MBC Access Road Drainage Improvements
ADDENDUM "B"
Page 1 of 2
Minimum Seeding Requirements for the MBC Access Road Drainage Improvements Project The existing concrete swale is in various stages of disrepair due to subsidence and erosion damage. Per the work shown in the plans, is recommended to repair the swale, install the French Drain system and provide the minimum recommended seed mix table as described below: 1. Clear and Grub any existing vegetation in the footprint of work and grade to drain per plan. 2. Add fertilizer and hydroseed the graded area using the minimum lbs/acre of the components recommended in the seed table below. 3. Water and maintain periodically until 70% vegetated cover is achieved.
Species Atemisia californica Eriogonum fasciculatum Lotus scorparius Nassella pulchra Salvia apiana Sisyrinchium bellum Vulpia microstachys
Table 1 - Hydroseed Mix Components Common Name Bulk #’s/acre California Sagebrush 2.0 California Buckwheat 12.0 Deerweed 4.0 Purple Needle Grass 8.0 White Sage 3.0 Blue-eyed Grass 3.0 Small Fescue 6.0
Min % PLS* 10% 10% 85% 75% 25% 80% 85%
* Min % PLS (Pure Live Seed) = Seed Purity X Germination Rate
The proposed seed mix can be altered or changed at the request of the City Botanist, Landscape Architect, horticulture/landscape specialist or other personnel versed in the plant palate for the City of San Diego. Please note that the City of San Diego has reviewed and approved the above seed mix (on January 20, 2011) as provided in Table 1- Hydroseed Mix Components, above. Should you have any questions regarding these minimum requirements, please contact me at your earliest convenience. Thank you for your time and attention. Very truly yours, BROWN AND CALDWELL
Christian Herencia, P.E. Project Manager
October 24, 2011 MBC Access Road Drainage Improvements
ADDENDUM "B"
Page 2 of 2
L-12-3794-DBB-B B-00316 2011 7 CA
For which proposals will be received at the Public Works Contracting Group, 1200 Third Avenue, Suite 200, San Diego, California, until 1:30 PM on November 1, 2011. A.
CHANGES TO CONTRACT DOCUMENTS The following changes to the Contract Documents are hereby made effective as though originally issued with the bid package.
B.
ADDENDUM “A” 1. To Question and Answer 5, DELETE in its entirety and SUBSTITUTE with the following: Q5.
What is permanent hydroseed mix specification? Do you want tackifier? Is this an irrigated or non-irrigated mix? Is there maintenance expected of contractor after hydroseeding is done?
A5.
Project re-vegetation requirements and hydroseed mix shall be per the attached approved Minimum Seeding Requirements Plan, page 2 of 2 of this Addendum. Contractor shall be responsible to establish vegetation to 70% coverage level. Following this, City or Caltrans will take over maintenance for re-vegetated areas.
Tony Heinrichs, Director Public Works Department Dated: October 24, 2011 San Diego, California TH/nb/cg/ez/ls
October 24, 2011 MBC Access Road Drainage Improvements
ADDENDUM "B"
Page 1 of 2
Minimum Seeding Requirements for the MBC Access Road Drainage Improvements Project The existing concrete swale is in various stages of disrepair due to subsidence and erosion damage. Per the work shown in the plans, is recommended to repair the swale, install the French Drain system and provide the minimum recommended seed mix table as described below: 1. Clear and Grub any existing vegetation in the footprint of work and grade to drain per plan. 2. Add fertilizer and hydroseed the graded area using the minimum lbs/acre of the components recommended in the seed table below. 3. Water and maintain periodically until 70% vegetated cover is achieved.
Species Atemisia californica Eriogonum fasciculatum Lotus scorparius Nassella pulchra Salvia apiana Sisyrinchium bellum Vulpia microstachys
Table 1 - Hydroseed Mix Components Common Name Bulk #’s/acre California Sagebrush 2.0 California Buckwheat 12.0 Deerweed 4.0 Purple Needle Grass 8.0 White Sage 3.0 Blue-eyed Grass 3.0 Small Fescue 6.0
Min % PLS* 10% 10% 85% 75% 25% 80% 85%
* Min % PLS (Pure Live Seed) = Seed Purity X Germination Rate
The proposed seed mix can be altered or changed at the request of the City Botanist, Landscape Architect, horticulture/landscape specialist or other personnel versed in the plant palate for the City of San Diego. Please note that the City of San Diego has reviewed and approved the above seed mix (on January 20, 2011) as provided in Table 1- Hydroseed Mix Components, above. Should you have any questions regarding these minimum requirements, please contact me at your earliest convenience. Thank you for your time and attention. Very truly yours, BROWN AND CALDWELL
Christian Herencia, P.E. Project Manager
October 24, 2011 MBC Access Road Drainage Improvements
ADDENDUM "B"
Page 2 of 2
